/**
 * PANDA 3D SOFTWARE
 * Copyright (c) Carnegie Mellon University.  All rights reserved.
 *
 * All use of this software is subject to the terms of the revised BSD
 * license.  You should have received a copy of this license along
 * with this source code in a file named "LICENSE."
 *
 * @file p3dInstance.cxx
 * @author drose
 * @date 2009-05-29
 */

#include "p3dInstance.h"
#include "p3dInstanceManager.h"
#include "p3dDownload.h"
#include "p3dSession.h"
#include "p3dPackage.h"
#include "p3dSplashWindow.h"
#include "p3dWinSplashWindow.h"
#include "p3dOsxSplashWindow.h"
#include "p3dX11SplashWindow.h"
#include "p3dObject.h"
#include "p3dMainObject.h"
#include "p3dUndefinedObject.h"
#include "p3dMultifileReader.h"
#include "p3dTemporaryFile.h"
#include "parse_color.h"

#include <sstream>
#include <algorithm>

#ifdef __APPLE__
#include <sys/mman.h>
#include <ApplicationServices/ApplicationServices.h>

// Lifted from NSEvent.h (which is Objective-C).
enum {
   NSAlphaShiftKeyMask = 1 << 16,
   NSShiftKeyMask      = 1 << 17,
   NSControlKeyMask    = 1 << 18,
   NSAlternateKeyMask  = 1 << 19,
   NSCommandKeyMask    = 1 << 20,
   NSNumericPadKeyMask = 1 << 21,
   NSHelpKeyMask       = 1 << 22,
   NSFunctionKeyMask   = 1 << 23,
   NSDeviceIndependentModifierFlagsMask = 0xffff0000U
};

#endif  // __APPLE__

#ifdef _WIN32
typedef P3DWinSplashWindow SplashWindowType;
#elif defined(__APPLE__) && !__LP64__
typedef P3DOsxSplashWindow SplashWindowType;
#elif defined(HAVE_X11)
typedef P3DX11SplashWindow SplashWindowType;
#else
typedef P3DSplashWindow SplashWindowType;
#endif

// The amount of time (in seconds) over which we average the total download
// time, for smoothing out the time estimate.
static const double time_average = 10.0;

// These are the various image files we might download for use in the splash
// window.  This list must match the ImageType enum.
const char *P3DInstance::_image_type_names[P3DInstance::IT_num_image_types] = {
  "download",
  "unauth",
  "ready",
  "failed",
  "launch",
  "active",
  "auth_ready",
  "auth_rollover",
  "auth_click",
  "play_ready",
  "play_rollover",
  "play_click",
  "none",  // Not really used.
};

static void
write_str(ostream &out, const wchar_t *str) {
  const wchar_t *p = str;
  while (*p != 0) {
    out << (int)*p << ' ';
    ++p;
  }
}

/**
 *
 */
P3DInstance::
P3DInstance(P3D_request_ready_func *func,
            const P3D_token tokens[], size_t num_tokens,
            int argc, const char *argv[], void *user_data) :
  _func(func)
{
  _dom_object = NULL;
  _main_object = new P3DMainObject;
  _main_object->set_instance(this);
  _user_data = user_data;
  _request_pending = false;
  _total_time_reports = 0;
  _temp_p3d_filename = NULL;
  _image_package = NULL;
  _current_background_image = IT_none;
  _current_button_image = IT_none;
  _got_fparams = false;
  _got_wparams = false;
  _p3d_trusted = false;
  _xpackage = NULL;
  _certlist_package = NULL;
  _p3dcert_package = NULL;

  _fparams.set_tokens(tokens, num_tokens);
  _fparams.set_args(argc, argv);

  nout << "Creating P3DInstance " << this << ": ";
  for (int i = 0; i < _fparams.get_num_tokens(); ++i) {
    nout << " " << _fparams.get_token_keyword(i)
         << "=\"" << _fparams.get_token_value(i) << "\"";
  }
  nout << "\n";

  P3DInstanceManager *inst_mgr = P3DInstanceManager::get_global_ptr();
  _instance_id = inst_mgr->get_unique_id();
  _hidden = (_fparams.lookup_token_int("hidden") != 0);
  _matches_run_origin = true;
  _matches_script_origin = false;
  _allow_python_dev = false;
  _keep_user_env = (_fparams.lookup_token_int("keep_user_env") != 0);
  _auto_start = (_fparams.lookup_token_int("auto_start") != 0);
  _stop_on_ready = (_fparams.lookup_token_int("stop_on_ready") != 0);
  _auto_install = true;
  if (_fparams.has_token("auto_install")) {
    _auto_install = (_fparams.lookup_token_int("auto_install") != 0);
  }
  _auth_button_clicked = false;
  _failed = false;
  _session = NULL;
  _auth_session = NULL;
  _panda3d_package = NULL;
  _splash_window = NULL;
  _instance_window_opened = false;
  _instance_window_attached = false;
  _stuff_to_download = false;
  _download_package_index = 0;
  _prev_downloaded = 0;
  _total_download_size = 0;
  _total_downloaded = 0;
  _packages_specified = false;
  _download_started = false;
  _download_complete = false;
  _instance_started = false;

  INIT_LOCK(_request_lock);
  _requested_stop = false;

#ifdef __APPLE__
  _shared_fd = -1;
  _shared_mmap_size = 0;
  _swbuffer = NULL;
  _reversed_buffer = NULL;
  _buffer_data = NULL;
  _data_provider = NULL;
  _buffer_color_space = NULL;
  _buffer_image = NULL;

  // We have to start with _mouse_active true; firefox doesn't send activate
  // events.
  _mouse_active = true;
  _modifiers = 0;
  _frame_timer = NULL;
#endif  // __APPLE__

  // Set some initial properties.
  _main_object->set_float_property("instanceDownloadProgress", 0.0);
  _main_object->set_float_property("downloadProgress", 0.0);
  _main_object->set_undefined_property("downloadElapsedSeconds");
  _main_object->set_undefined_property("downloadElapsedFormatted");
  _main_object->set_undefined_property("downloadRemainingSeconds");
  _main_object->set_undefined_property("downloadRemainingFormatted");
  _main_object->set_string_property("downloadPackageName", "");
  _main_object->set_string_property("downloadPackageDisplayName", "");
  _main_object->set_bool_property("downloadComplete", false);
  _main_object->set_string_property("status", "initial");

  ostringstream stream;
  stream << inst_mgr->get_plugin_major_version() << "."
         << inst_mgr->get_plugin_minor_version() << "."
         << inst_mgr->get_plugin_sequence_version();
  if (!inst_mgr->get_plugin_official_version()) {
    stream << "c";
  }

  // The plugin version as a single number, with three digits reserved for
  // each component.
  int numeric_version =
    inst_mgr->get_plugin_major_version() * 1000000 +
    inst_mgr->get_plugin_minor_version() * 1000 +
    inst_mgr->get_plugin_sequence_version();
  if (!inst_mgr->get_plugin_official_version()) {
    // Subtract 1 if we are not an official version.
    --numeric_version;
  }

  _main_object->set_string_property("pluginVersionString", stream.str());
  _main_object->set_int_property("pluginMajorVersion", inst_mgr->get_plugin_major_version());
  _main_object->set_int_property("pluginMinorVersion", inst_mgr->get_plugin_minor_version());
  _main_object->set_int_property("pluginSequenceVersion", inst_mgr->get_plugin_sequence_version());
  _main_object->set_bool_property("pluginOfficialVersion", inst_mgr->get_plugin_official_version());
  _main_object->set_int_property("pluginNumericVersion", numeric_version);
  _main_object->set_string_property("pluginDistributor", inst_mgr->get_plugin_distributor());
  _main_object->set_string_property("coreapiHostUrl", inst_mgr->get_coreapi_host_url());
  time_t timestamp = inst_mgr->get_coreapi_timestamp();
  _main_object->set_int_property("coreapiTimestamp", (int)timestamp);
  const char *timestamp_string = ctime(&timestamp);
  if (timestamp_string == NULL) {
    timestamp_string = "";
  }
  _main_object->set_string_property("coreapiTimestampString", timestamp_string);
  _main_object->set_string_property("coreapiVersionString", inst_mgr->get_coreapi_set_ver());

  _main_object->set_bool_property("trustedEnvironment", (int)inst_mgr->get_trusted_environment());
  _main_object->set_bool_property("consoleEnvironment", (int)inst_mgr->get_console_environment());

  // We'll start off with the "download" image displayed in the splash window
  // (when it opens), until we get stuff downloaded.
  set_background_image(IT_download);

  // We'd better ask for the image package up front, even if it turns out we
  // don't need it for this particular app.  We'll probably use it eventually,
  // and it's good to have it loaded early, so we can put up a splash image
  // (for instance, the above IT_download image) while we download the real
  // contents.
  P3DHost *host = inst_mgr->get_host(inst_mgr->get_host_url());
  _image_package = host->get_package("images", "", "", "");
  if (_image_package != NULL) {
    _image_package->add_instance(this);
  }

  // Check if the window size has been explicitly set to 0.  This means we
  // have an explicitly hidden plugin, and we should be prepared not to get a
  // wparams from the browser.
  if (_fparams.has_token("width") && _fparams.has_token("height") &&
      (_fparams.lookup_token_int("width") == 0 ||
       _fparams.lookup_token_int("height") == 0)) {
    P3D_window_handle dummy_handle;
    memset(&dummy_handle, 0, sizeof(dummy_handle));
    P3DWindowParams wparams(P3D_WT_hidden, 0, 0, 0, 0, dummy_handle);
    set_wparams(wparams);
  }
}

/**
 *
 */
P3DInstance::
~P3DInstance() {
  assert(_session == NULL);
  cleanup();

  if (_dom_object != NULL) {
    P3D_OBJECT_DECREF(_dom_object);
    _dom_object = NULL;
  }

  if (_main_object != NULL) {
    nout << "panda_script_object ref = "
         << _main_object->_ref_count << "\n";
    _main_object->set_instance(NULL);
    P3D_OBJECT_DECREF(_main_object);
    _main_object = NULL;
  }

  Downloads::iterator di;
  for (di = _downloads.begin(); di != _downloads.end(); ++di) {
    P3DDownload *download = (*di).second;
    if (download->get_instance() == this) {
      download->set_instance(NULL);
    }
    p3d_unref_delete(download);
  }
  _downloads.clear();

  DESTROY_LOCK(_request_lock);

  // TODO: Is it possible for someone to delete an instance while a download
  // is still running?  Who will crash when this happens?
}

/**
 * Invalidates the instance and removes any structures prior to deleting.
 */
void P3DInstance::
cleanup() {
  _failed = true;

  if (_auth_session != NULL) {
    _auth_session->shutdown(false);
    p3d_unref_delete(_auth_session);
    _auth_session = NULL;
  }

  for (int i = 0; i < (int)IT_num_image_types; ++i) {
    _image_files[i].cleanup();
  }

  // Tell all of the packages that we're no longer in business for them.
  Packages::iterator pi;
  for (pi = _packages.begin(); pi != _packages.end(); ++pi) {
    (*pi)->remove_instance(this);
  }
  _packages.clear();
  if (_image_package != NULL) {
    _image_package->remove_instance(this);
    _image_package = NULL;
  }

  if (_certlist_package != NULL) {
    _certlist_package->remove_instance(this);
    _certlist_package = NULL;
  }

  if (_p3dcert_package != NULL) {
    _p3dcert_package->remove_instance(this);
    _p3dcert_package = NULL;
  }

  if (_splash_window != NULL) {
    delete _splash_window;
    _splash_window = NULL;
  }

  if (_temp_p3d_filename != NULL) {
    delete _temp_p3d_filename;
    _temp_p3d_filename = NULL;
  }

  if (_xpackage != NULL) {
    delete _xpackage;
    _xpackage = NULL;
  }

#ifdef __APPLE__
  if (_frame_timer != NULL) {
    CFRunLoopTimerInvalidate(_frame_timer);
    CFRelease(_frame_timer);
    _frame_timer = NULL;
  }

  free_swbuffer();
#endif

  TiXmlDocument *doc = NULL;
  ACQUIRE_LOCK(_request_lock);
  RawRequests::iterator ri;
  for (ri = _raw_requests.begin(); ri != _raw_requests.end(); ++ri) {
    doc = (*ri);
    delete doc;
  }
  _raw_requests.clear();
  RELEASE_LOCK(_request_lock);

  BakedRequests::iterator bi;
  for (bi = _baked_requests.begin(); bi != _baked_requests.end(); ++bi) {
    P3D_request *request = (*bi);
    finish_request(request, false);
  }
  _baked_requests.clear();

  Downloads::iterator di;
  for (di = _downloads.begin(); di != _downloads.end(); ++di) {
    P3DDownload *download = (*di).second;
    download->cancel();
  }
}


/**
 * Specifies a URL that should be contacted to download the instance data.
 * Normally this, or set_p3d_filename() or make_p3d_stream(), is only called
 * once.
 *
 * The instance data at the other end of this URL is key.  We can't start the
 * instance until we have downloaded the instance file and examined the
 * p3d_info.xml, and we know what Python version we need and so forth.
 */
void P3DInstance::
set_p3d_url(const string &p3d_url) {
  if (p3d_url.empty()) {
    nout << "No p3d URL specified.  Cannot run.\n";
    set_failed();
    return;
  }
  _fparams.set_p3d_url(p3d_url);

  // Save the last part of the URL as the p3d_basename, for reporting purposes
  // or whatever.
  determine_p3d_basename(p3d_url);

  // Make a temporary file to receive the instance data.
  assert(_temp_p3d_filename == NULL);
  _temp_p3d_filename = new P3DTemporaryFile(".p3d");
  _stuff_to_download = true;

  // Maybe it's time to open a splash window now.
  make_splash_window();

  // Mark the time we started downloading, so we'll know when to reveal the
  // progress bar, and we can predict the total download time.
#ifdef _WIN32
  _start_dl_tick = GetTickCount();
#else
  gettimeofday(&_start_dl_timeval, NULL);
#endif
  _show_dl_instance_progress = false;

  // Start downloading the data.
  InstanceDownload *download = new InstanceDownload(this);
  download->set_url(p3d_url);
  download->set_filename(_temp_p3d_filename->get_filename());
  if (_fparams.has_token("p3d_size")) {
    download->set_total_expected_data(_fparams.lookup_token_int("p3d_size"));
  }

  _main_object->set_string_property("status", "downloading_instance");
  start_download(download);
}

/**
 * Indicates an intention to transmit the p3d data as a stream.  Should return
 * a new unique stream ID to receive it.
 */
int P3DInstance::
make_p3d_stream(const string &p3d_url) {
  _fparams.set_p3d_url(p3d_url);

  // Save the last part of the URL as the p3d_basename, for reporting purposes
  // or whatever.
  determine_p3d_basename(p3d_url);

  // Make a temporary file to receive the instance data.
  assert(_temp_p3d_filename == NULL);
  _temp_p3d_filename = new P3DTemporaryFile(".p3d");
  _stuff_to_download = true;

  // Maybe it's time to open a splash window now.
  make_splash_window();

  // Mark the time we started downloading, so we'll know when to reveal the
  // progress bar.
#ifdef _WIN32
  _start_dl_tick = GetTickCount();
#else
  gettimeofday(&_start_dl_timeval, NULL);
#endif
  _show_dl_instance_progress = false;

  // Start downloading the data.
  InstanceDownload *download = new InstanceDownload(this);
  download->set_url(p3d_url);
  download->set_filename(_temp_p3d_filename->get_filename());
  if (_fparams.has_token("p3d_size")) {
    download->set_total_expected_data(_fparams.lookup_token_int("p3d_size"));
  }

  _main_object->set_string_property("status", "downloading_instance");
  return start_download(download, false);
}

/**
 * Specifies the file that contains the instance data.  Normally this is only
 * called once.
 */
void P3DInstance::
set_p3d_filename(const string &p3d_filename, const int &p3d_offset) {
  determine_p3d_basename(p3d_filename);
  priv_set_p3d_filename(p3d_filename, p3d_offset);
}

/**
 * Changes the window parameters, e.g.  to resize or reposition the window; or
 * sets the parameters for the first time, creating the initial window.
 */
void P3DInstance::
set_wparams(const P3DWindowParams &wparams) {
  bool prev_got_wparams = _got_wparams;
  _got_wparams = true;
  _wparams = wparams;

  nout << "set_wparams: " << wparams.get_window_type()
       << " " << wparams.get_win_width() << " " << wparams.get_win_height()
       << "\n";

  if (_hidden || _wparams.get_win_width() == 0 || _wparams.get_win_height() == 0) {
    // If we're a hidden app, or if the window has no size, then it is really
    // a hidden window, regardless of what type it claims to be.
    _wparams.set_window_type(P3D_WT_hidden);
  }

  if (_wparams.get_window_type() != P3D_WT_hidden) {
    // Update or create the splash window.
    if (_splash_window != NULL) {
      _splash_window->set_wparams(_wparams);
    } else {
      make_splash_window();
    }
  }

  // It doesn't make much sense to go further than this point if the instance
  // is already in the failed state.
  if (is_failed()) {
    return;
  }

  if (_wparams.get_window_type() != P3D_WT_hidden) {
#ifdef __APPLE__
    // On Mac, we have to communicate the results of the rendering back via
    // shared memory, instead of directly parenting windows to the browser.
    // Set up this mechanism.
    int x_size = _wparams.get_win_width();
    int y_size = _wparams.get_win_height();
    if (x_size != 0 && y_size != 0) {
      if (_swbuffer == NULL || _swbuffer->get_x_size() != x_size ||
          _swbuffer->get_y_size() != y_size) {
        // We need to open a new shared buffer.
        alloc_swbuffer();
      }

      if (_swbuffer == NULL) {
        nout << "Could not open swbuffer\n";
      }
    }
#endif   // __APPLE__
  }

  // Update the instance in the sub-process.
  if (_session != NULL) {
    TiXmlDocument *doc = new TiXmlDocument;
    TiXmlElement *xcommand = new TiXmlElement("command");
    xcommand->SetAttribute("cmd", "setup_window");
    xcommand->SetAttribute("instance_id", get_instance_id());
    TiXmlElement *xwparams = _wparams.make_xml(this);

    doc->LinkEndChild(xcommand);
    xcommand->LinkEndChild(xwparams);

    _session->send_command(doc);
  }

  if (!prev_got_wparams) {
    // If this was the first set_wparams call, try to start the app.
    if (_p3d_trusted && get_packages_ready()) {
      ready_to_start();
    }
  }
}

/**
 * Returns a pointer to the top-level scriptable object of the instance, to be
 * used by JavaScript code in the browser to control this program.
 */
P3D_object *P3DInstance::
get_panda_script_object() const {
  nout << "get_panda_script_object\n";
  return _main_object;
}

/**
 * Stores a pointer to the top-level window object of the browser, to be used
 * by Panda code to control JavaScript.  The new object's reference count is
 * incremented, and the previous object's is decremented.
 */
void P3DInstance::
set_browser_script_object(P3D_object *browser_script_object) {
  nout << "set_browser_script_object\n";
  if (browser_script_object != _dom_object) {
    P3D_OBJECT_XDECREF(_dom_object);
    _dom_object = browser_script_object;
    if (_dom_object != NULL) {
      P3D_OBJECT_INCREF(_dom_object);
    }

    if (_session != NULL) {
      send_browser_script_object();
    }
  }

  // Query the origin: protocol, hostname, and port.  We'll use this to limit
  // access to the scripting interfaces for a particular p3d file.
  _origin_protocol.clear();
  _origin_hostname.clear();
  _origin_port.clear();
  if (_dom_object != NULL) {
    P3D_object *location = P3D_OBJECT_GET_PROPERTY(_dom_object, "location");
    if (location != NULL) {
      P3D_object *protocol = P3D_OBJECT_GET_PROPERTY(location, "protocol");
      if (protocol != NULL) {
        int size = P3D_OBJECT_GET_STRING(protocol, NULL, 0);
        char *buffer = new char[size];
        P3D_OBJECT_GET_STRING(protocol, buffer, size);
        _origin_protocol = string(buffer, size);
        delete [] buffer;
        P3D_OBJECT_DECREF(protocol);
      }

      P3D_object *hostname = P3D_OBJECT_GET_PROPERTY(location, "hostname");
      if (hostname != NULL) {
        int size = P3D_OBJECT_GET_STRING(hostname, NULL, 0);
        char *buffer = new char[size];
        P3D_OBJECT_GET_STRING(hostname, buffer, size);
        _origin_hostname = string(buffer, size);
        delete [] buffer;
        P3D_OBJECT_DECREF(hostname);
      }

      P3D_object *port = P3D_OBJECT_GET_PROPERTY(location, "port");
      if (port != NULL) {
        int size = P3D_OBJECT_GET_STRING(port, NULL, 0);
        char *buffer = new char[size];
        P3D_OBJECT_GET_STRING(port, buffer, size);
        _origin_port = string(buffer, size);
        delete [] buffer;
        P3D_OBJECT_DECREF(port);
      }

      if (_origin_hostname.empty() && _origin_protocol == "file:") {
        _origin_hostname = "localhost";
      }

      if (_origin_port.empty()) {
        // Maybe the actual URL doesn't include the port, in which case it is
        // implicit.
        if (_origin_protocol == "http:") {
          _origin_port = "80";
        } else if (_origin_protocol == "https:") {
          _origin_port = "443";
        }
      }

      P3D_OBJECT_DECREF(location);
    }
  }

  nout << "origin is " << _origin_protocol << "//" << _origin_hostname;
  if (!_origin_port.empty()) {
    nout << ":" << _origin_port;
  }
  nout << "\n";
}


/**
 * Returns true if the instance has any pending requests at the time of this
 * call, false otherwise.
 */
bool P3DInstance::
has_request() {
  return _request_pending;
}

/**
 * Returns a newly-allocated P3D_request corresponding to the pending request
 * for the host, or NULL if there is no pending request.  If the return value
 * is non-NULL, it should eventually be passed back to finish_request() for
 * cleanup.
 */
P3D_request *P3DInstance::
get_request() {
  bake_requests();
  if (_baked_requests.empty()) {
    // No requests ready.
    _request_pending = false;
    return NULL;
  }

  P3D_request *request = _baked_requests.front();
  _baked_requests.pop_front();
  _request_pending = !_baked_requests.empty();

  if (request != NULL) {
    switch (request->_request_type) {
    case P3D_RT_notify:
      {
        // Also eval the associated HTML token, if any.
        string message = request->_request._notify._message;
        string expression = _fparams.lookup_token(message);
        nout << "notify: " << message << " " << expression << "\n";
        if (!expression.empty() && _dom_object != NULL) {
          P3D_object *result = P3D_OBJECT_EVAL(_dom_object, expression.c_str());
          P3D_OBJECT_XDECREF(result);
        }
      }
      break;

    case P3D_RT_stop:
      {
        // We also send an implicit message when Python requests itself to
        // shutdown.
        _main_object->set_pyobj(NULL);
        _main_object->set_string_property("status", "stopped");

        string message = "onpythonstop";
        string expression = _fparams.lookup_token(message);
        nout << "notify: " << message << " " << expression << "\n";
        if (!expression.empty() && _dom_object != NULL) {
          P3D_object *result = P3D_OBJECT_EVAL(_dom_object, expression.c_str());
          P3D_OBJECT_XDECREF(result);
        }
      }
      break;

    case P3D_RT_callback:
      {
        // And when the callback request is extracted, we make the callback.
        P3D_callback_func *func = request->_request._callback._func;
        void *data = request->_request._callback._data;
        (*func)(data);
      }
      break;

    case P3D_RT_forget_package:
      {
        // We're being asked to forget a particular package.
        const char *host_url = request->_request._forget_package._host_url;
        const char *package_name = request->_request._forget_package._package_name;
        const char *package_version = request->_request._forget_package._package_version;
        if (package_version == NULL) {
          package_version = "";
        }

        P3DInstanceManager *inst_mgr = P3DInstanceManager::get_global_ptr();
        P3DHost *host = inst_mgr->get_host(host_url);
        if (package_name != NULL) {
          P3DPackage *package = host->get_package(package_name, package_version, _session_platform, "");
          host->forget_package(package);
        } else {
          // If a NULL package name is given, forget the whole host.
          inst_mgr->forget_host(host);
        }
      }
      break;

    default:
      break;
    }
  }

  return request;
}

/**
 * Copies requests from the _raw_requests queue, which is built up in one or
 * more sub-threads, into the _baked_requests queue, which is publicly
 * presented to the browser.  Along the way, some requests (like script
 * requests) are handled immediately.
 *
 * At the end of this call, _baked_requests will contain the current set of
 * requests pending for the browser.
 *
 * This method should only be called in the main thread.
 */
void P3DInstance::
bake_requests() {
  while (true) {
    // Get the latest request from the read thread.
    TiXmlDocument *doc = NULL;
    ACQUIRE_LOCK(_request_lock);
    if (!_raw_requests.empty()) {
      doc = _raw_requests.front();
      _raw_requests.pop_front();
    }
    RELEASE_LOCK(_request_lock);

    if (doc == NULL) {
      // No more requests to process right now.
      return;
    }

    // Now we've got a request in XML form; convert it to P3D_request form.
    TiXmlElement *xrequest = doc->FirstChildElement("request");
    assert(xrequest != (TiXmlElement *)NULL);
    P3D_request *request = make_p3d_request(xrequest);
    delete doc;

    if (request != NULL) {
      _baked_requests.push_back(request);
    }
  }
}

/**
 * May be called in any thread to add a new XML request to the pending_request
 * queue for this instance.  The XML document will be deleted when the request
 * is eventually handled.
 */
void P3DInstance::
add_raw_request(TiXmlDocument *doc) {
  ACQUIRE_LOCK(_request_lock);
  _raw_requests.push_back(doc);
  _request_pending = true;
  RELEASE_LOCK(_request_lock);

  // We don't decode the XML yet, since we might be running in any thread
  // here.  We'll decode it in the main thread, where it's safe.

  // Tell the world we've got a new request.
  P3DInstanceManager *inst_mgr = P3DInstanceManager::get_global_ptr();
  inst_mgr->signal_request_ready(this);
  if (_session != NULL) {
    _session->signal_request_ready(this);
  }
}

/**
 * May be called in the main thread only to add a new request to the
 * baked_request queue.  This request queue is directly passed on the browser
 * without further processing at this level.
 */
void P3DInstance::
add_baked_request(P3D_request *request) {
  assert(request->_instance == NULL);
  request->_instance = this;
  ref();

  _baked_requests.push_back(request);
  _request_pending = true;

  // Tell the world we've got a new request.
  P3DInstanceManager *inst_mgr = P3DInstanceManager::get_global_ptr();
  inst_mgr->signal_request_ready(this);
}

/**
 * Deallocates a previously-returned request from get_request().  If handled
 * is true, the request has been handled by the host; otherwise, it has been
 * ignored.
 */
void P3DInstance::
finish_request(P3D_request *request, bool handled) {
  assert(request != NULL);
  if (request->_instance == NULL) {
    nout << "Ignoring empty request " << request << "\n";
    return;
  }

  P3DInstanceManager *inst_mgr = P3DInstanceManager::get_global_ptr();
  if (inst_mgr->validate_instance(request->_instance) == NULL) {
    // nout << "Ignoring unknown request " << request << "\n";
    return;
  }

  switch (request->_request_type) {
  case P3D_RT_stop:
    break;

  case P3D_RT_get_url:
    if (request->_request._get_url._url != NULL) {
      free((char *)request->_request._get_url._url);
      request->_request._get_url._url = NULL;
    }
    break;

  case P3D_RT_notify:
    if (request->_request._notify._message != NULL) {
      free((char *)request->_request._notify._message);
      request->_request._notify._message = NULL;
    }
    break;

  case P3D_RT_forget_package:
    if (request->_request._forget_package._host_url != NULL) {
      free((char *)request->_request._forget_package._host_url);
      request->_request._forget_package._host_url = NULL;
    }
    if (request->_request._forget_package._package_name != NULL) {
      free((char *)request->_request._forget_package._package_name);
      request->_request._forget_package._package_name = NULL;
    }
    if (request->_request._forget_package._package_version != NULL) {
      free((char *)request->_request._forget_package._package_version);
      request->_request._forget_package._package_version = NULL;
    }
    break;

  default:
    break;
  }

  p3d_unref_delete(((P3DInstance *)request->_instance));
  request->_instance = NULL;

  delete request;
}

/**
 * Called by the host in response to a get_url request, this sends the data
 * retrieved from the requested URL, a piece at a time.
 */
bool P3DInstance::
feed_url_stream(int unique_id,
                P3D_result_code result_code,
                int http_status_code,
                size_t total_expected_data,
                const unsigned char *this_data,
                size_t this_data_size) {
  Downloads::iterator di = _downloads.find(unique_id);
  if (di == _downloads.end()) {
    nout << "Unexpected feed_url_stream for " << unique_id << "\n";
    // Don't know this request.
    return false;
  }

  P3DDownload *download = (*di).second;
  assert(download->get_instance() == this);
  bool download_ok = download->feed_url_stream
    (result_code, http_status_code, total_expected_data,
     this_data, this_data_size);

  if (!download_ok || download->get_download_finished()) {
    // All done.
    if (download->get_instance() == this) {
      download->set_instance(NULL);
    }
    _downloads.erase(di);
    p3d_unref_delete(download);
  }

  return download_ok;
}

/**
 * Responds to the os-generated window event.  Returns true if the event is
 * handled, false if ignored.
 */
bool P3DInstance::
handle_event(const P3D_event_data &event) {
  bool retval = false;
  if (_splash_window != NULL) {
    if (_splash_window->handle_event(event)) {
      retval = true;
    }
  }

#if defined(__APPLE__)
  if (event._event_type == P3D_ET_osx_event_record) {
    retval = handle_event_osx_event_record(event);
  } else if (event._event_type == P3D_ET_osx_cocoa) {
    retval = handle_event_osx_cocoa(event);
  } else {
    assert(false);
  }
#endif  // __APPLE__

  return retval;
}

/**
 * Returns the log filename for this particular session, if the session was
 * started and if it has a log file.  Returns empty string if the session
 * never started or if it lacks a log file.
 *
 * This is the same value returned by P3DSession::get_log_pathname(), except
 * that it remains valid even after the session has closed.
 */
const string &P3DInstance::
get_log_pathname() const {
  if (_session != NULL) {
    return _session->_log_pathname;
  }
  return _log_pathname;
}

/**
 * Adds the package to the list of packages used by this instance.  The
 * instance will share responsibility for downloading the package with any of
 * the other instances that use the same package.
 *
 * The seq value should be the expected minimum package_seq value for the
 * indicated package.  If the given seq value is higher than the package_seq
 * value in the contents.xml file cached for the host, it is a sign that the
 * contents.xml file is out of date and needs to be redownloaded.
 */
void P3DInstance::
add_package(const string &name, const string &version, const string &seq,
            P3DHost *host) {
  string alt_host = _fparams.lookup_token("alt_host");

  // Look up in the p3d_info.xml file to see if this p3d file has a specific
  // alt_host indication for this host_url.
  string alt_host_url = find_alt_host_url(host->get_host_url(), alt_host);
  if (!alt_host_url.empty()) {
    // If it does, we go ahead and switch to that host now, instead of
    // bothering to contact the original host.
    P3DInstanceManager *inst_mgr = P3DInstanceManager::get_global_ptr();
    host = inst_mgr->get_host(alt_host_url);
    alt_host.clear();
  }

  if (!host->has_contents_file()) {
    // Since we haven't downloaded this host's contents.xml file yet, get its
    // additional host information.
    get_host_info(host);
  }

  P3DPackage *package = host->get_package(name, version, _session_platform,
                                          seq, alt_host);
  add_package(package);
}

/**
 * Adds the package to the list of packages used by this instance.  The
 * instance will share responsibility for downloading the package with any of
 * the other instances that use the same package.
 */
void P3DInstance::
add_package(P3DPackage *package) {
  if (find(_packages.begin(), _packages.end(), package) != _packages.end()) {
    // Already have this package.
    return;
  }

  if (package->get_package_name() == "panda3d") {
    _panda3d_package = package;
  }

  _packages.push_back(package);

  // This call must be at the end of this method, because it might ultimately
  // start the application before it returns (if this was the last required
  // package).
  package->add_instance(this);
}

/**
 * Indicates that the given package is destructing and this instance should no
 * longer retain a pointer to it.  This is normally called only by the
 * P3DPackage destructor, and it invalidates the instance.
 */
void P3DInstance::
remove_package(P3DPackage *package) {
  Packages::iterator pi = find(_packages.begin(), _packages.end(), package);
  if (pi != _packages.end()) {
    _packages.erase(pi);
  }
  pi = find(_downloading_packages.begin(), _downloading_packages.end(), package);
  if (pi != _downloading_packages.end()) {
    _downloading_packages.erase(pi);
  }
  if (package == _image_package) {
    _image_package = NULL;
  }
  if (package == _certlist_package) {
    _certlist_package = NULL;
  }
  if (package == _p3dcert_package) {
    _p3dcert_package = NULL;
  }
  if (package == _panda3d_package) {
    _panda3d_package = NULL;
  }

  set_failed();
}

/**
 * Returns true if all of the packages required by the instance have their
 * information available and are ready to be downloaded, false if one or more
 * of them is still waiting for information (or has failed).
 */
bool P3DInstance::
get_packages_info_ready() const {
  if (!_packages_specified) {
    // We haven't even specified the full set of required packages yet.
    return false;
  }

  Packages::const_iterator pi;
  for (pi = _packages.begin(); pi != _packages.end(); ++pi) {
    if (!(*pi)->get_info_ready()) {
      return false;
    }
  }

  return true;
}

/**
 * Returns true if all of the packages required by the instance (as specified
 * in previous calls to add_package()) have been fully downloaded and are
 * ready to run, or false if one or more of them still requires downloading.
 */
bool P3DInstance::
get_packages_ready() const {
  if (!_packages_specified) {
    // We haven't even specified the full set of required packages yet.
    return false;
  }

  Packages::const_iterator pi;
  for (pi = _packages.begin(); pi != _packages.end(); ++pi) {
    if (!(*pi)->get_ready()) {
      return false;
    }
  }

  return true;
}

/**
 * Returns true if any of the packages required by the instance have failed to
 * download (and thus we will never be ready).
 */
bool P3DInstance::
get_packages_failed() const {
  Packages::const_iterator pi;
  for (pi = _packages.begin(); pi != _packages.end(); ++pi) {
    if ((*pi)->get_failed()) {
      return true;
    }
  }

  return false;
}

/**
 * Adds a newly-allocated P3DDownload object to the download queue, and issues
 * the request to start it downloading.  As the download data comes in, it
 * will be fed to the download object.
 *
 * This increments the P3DDownload object's reference count, and will
 * decrement it (and possibly delete the object) after download_finished() has
 * been called.
 *
 * add_request should be true to actually request the URL from the plugin, or
 * false not to.  Normally, this should always be set true, except in the one
 * special case of make_p3d_stream(), in which case the plugin is already
 * prepared to send the stream and doesn't need to have it requested.
 *
 * Returns the unique ID of this stream.
 */
int P3DInstance::
start_download(P3DDownload *download, bool add_request) {
  assert(download->get_download_id() == 0);
  assert(!download->get_url().empty());

  if (is_failed()) {
    // Can't download anything more after failure.
    download->cancel();
    return 0;
  }

  P3DInstanceManager *inst_mgr = P3DInstanceManager::get_global_ptr();

  int download_id = inst_mgr->get_unique_id();
  download->set_download_id(download_id);
  download->set_instance(this);

  download->ref();
  bool inserted = _downloads.insert(Downloads::value_type(download_id, download)).second;
  assert(inserted);

  // add_request will be false only for the initial p3d stream, which the
  // plugin already knows about.  For all other download streams, add_request
  // is true in order to ask the plugin for the stream.
  if (add_request) {
    P3D_request *request = new P3D_request;
    request->_instance = NULL;
    request->_request_type = P3D_RT_get_url;
    request->_request._get_url._url = strdup(download->get_url().c_str());
    request->_request._get_url._unique_id = download_id;

    add_baked_request(request);
  }

  return download_id;
}

/**
 * Asks the host to shut down this particular instance, presumably because the
 * user has indicated it should exit.  This call may be made in any thread.
 */
void P3DInstance::
request_stop_sub_thread() {
  // Atomically check _requested_stop.
  bool add_request = false;
  ACQUIRE_LOCK(_request_lock);
  if (!_requested_stop) {
    _requested_stop = true;
    add_request = true;
  }
  RELEASE_LOCK(_request_lock);

  // If we haven't requested a stop already, do it now.
  if (add_request) {
    TiXmlDocument *doc = new TiXmlDocument;
    TiXmlElement *xrequest = new TiXmlElement("request");
    xrequest->SetAttribute("rtype", "stop");
    doc->LinkEndChild(xrequest);

    add_raw_request(doc);
  }
}

/**
 * Asks the host to shut down this particular instance, presumably because the
 * user has indicated it should exit.  This call may only be made in the main
 * thread.
 */
void P3DInstance::
request_stop_main_thread() {
  // Atomically check _requested_stop.
  bool add_request = false;
  ACQUIRE_LOCK(_request_lock);
  if (!_requested_stop) {
    _requested_stop = true;
    add_request = true;
  }
  RELEASE_LOCK(_request_lock);

  // If we haven't requested a stop already, do it now.
  if (add_request) {
    _requested_stop = true;
    P3D_request *request = new P3D_request;
    request->_instance = NULL;
    request->_request_type = P3D_RT_stop;
    add_baked_request(request);
  }
}

/**
 * Asks the host to refresh the plugin window.  This is only relevant for
 * windowless plugins, for instance, the way OSX plugins always run.
 */
void P3DInstance::
request_refresh() {
  P3D_request *request = new P3D_request;
  request->_instance = NULL;
  request->_request_type = P3D_RT_refresh;
  add_baked_request(request);
}

/**
 * Asks the host to make a callback later.
 */
void P3DInstance::
request_callback(P3D_callback_func *func, void *data) {
  P3D_request *request = new P3D_request;
  request->_instance = NULL;
  request->_request_type = P3D_RT_callback;
  request->_request._callback._func = func;
  request->_request._callback._data = data;
  add_baked_request(request);
}

/**
 * Returns a newly-allocated XML structure that corresponds to the data within
 * this instance.
 */
TiXmlElement *P3DInstance::
make_xml() {
  assert(_got_fparams);

  TiXmlElement *xinstance = new TiXmlElement("instance");
  xinstance->SetAttribute("instance_id", _instance_id);

  P3DInstanceManager *inst_mgr = P3DInstanceManager::get_global_ptr();
  xinstance->SetAttribute("root_dir", inst_mgr->get_root_dir());
  xinstance->SetAttribute("log_directory", inst_mgr->get_log_directory());
  xinstance->SetAttribute("verify_contents", (int)inst_mgr->get_verify_contents());

  // Tell the Panda process that it was started by a plugin that knows about
  // the new per_platform flag.
  xinstance->SetAttribute("respect_per_platform", 1);

  if (!inst_mgr->get_super_mirror().empty()) {
    xinstance->SetAttribute("super_mirror", inst_mgr->get_super_mirror());
  }


  TiXmlElement *xfparams = _fparams.make_xml();
  xinstance->LinkEndChild(xfparams);

  if (_got_wparams) {
    TiXmlElement *xwparams = _wparams.make_xml(this);
    xinstance->LinkEndChild(xwparams);
  }

  Packages::const_iterator pi;
  for (pi = _packages.begin(); pi != _packages.end(); ++pi) {
    TiXmlElement *xpackage = (*pi)->make_xml();
    xinstance->LinkEndChild(xpackage);
  }

  TiXmlElement *xmain = _session->p3dobj_to_xml(_main_object);
  xmain->SetValue("main");
  xinstance->LinkEndChild(xmain);

  return xinstance;
}

/**
 * Called by the P3DSplashWindow code (maybe in a sub-thread) when the user
 * clicks the button visible on the splash window.  This will forward the
 * event to the main thread via the request callback mechanism.
 */
void P3DInstance::
splash_button_clicked_sub_thread() {
  TiXmlDocument *doc = new TiXmlDocument;
  TiXmlElement *xrequest = new TiXmlElement("request");
  xrequest->SetAttribute("rtype", "notify");
  xrequest->SetAttribute("message", "buttonclick");
  doc->LinkEndChild(xrequest);

  add_raw_request(doc);
}

/**
 * Called only in the main thread, indirectly from
 * splash_button_clicked_sub_thread(), as the result of the user clicking on
 * the button visible in the splash window.
 */
void P3DInstance::
splash_button_clicked_main_thread() {
  if (is_failed()) {
    // Can't click the button after we've failed.
    nout << "Ignoring click for failed instance\n";
    return;
  }

  if (!_p3d_trusted) {
    auth_button_clicked();
  } else if (_session == NULL) {
    play_button_clicked();
  } else {
    nout << "Ignoring click for already-started instance\n";
  }
}

/**
 * Called to authorize the p3d file by the user clicking the red "auth"
 * button.
 */
void P3DInstance::
auth_button_clicked() {
  // Delete the previous session and create a new one.
  if (_auth_session != NULL) {
    _auth_session->shutdown(false);
    p3d_unref_delete(_auth_session);
    _auth_session = NULL;
  }

  P3DInstanceManager *inst_mgr = P3DInstanceManager::get_global_ptr();
  _auth_session = inst_mgr->authorize_instance(this);
  _auth_session->ref();
}

/**
 * Called to start the game by the user clicking the green "play" button, or
 * by JavaScript calling play().
 */
void P3DInstance::
play_button_clicked() {
  if (_session == NULL && _p3d_trusted) {
    set_button_image(IT_none);
    if (!_download_started) {
      // Now we initiate the download.
      _auto_install = true;
      _auto_start = true;
      if (get_packages_info_ready()) {
        ready_to_install();
      }

    } else {
      set_background_image(IT_launch);
      P3DInstanceManager *inst_mgr = P3DInstanceManager::get_global_ptr();
      inst_mgr->start_instance(this);
    }
  }
}

/**
 * Called by the P3DAuthSession code in a sub-thread when the auth dialog
 * exits (for instance, because the user approved the certificate, or
 * cancelled).
 */
void P3DInstance::
auth_finished_sub_thread() {
  TiXmlDocument *doc = new TiXmlDocument;
  TiXmlElement *xrequest = new TiXmlElement("request");
  xrequest->SetAttribute("rtype", "notify");
  xrequest->SetAttribute("message", "authfinished");
  doc->LinkEndChild(xrequest);

  add_raw_request(doc);
}

/**
 * Called only in the main thread, indirectly from auth_finished_sub_thread(),
 * as the result of the user closing the auth dialog.
 */
void P3DInstance::
auth_finished_main_thread() {
  // Set this flag to indicate that the user has clicked on the red "auth"
  // button.  This eliminates the need to click on the green "start" button.
  _auth_button_clicked = true;

  // After the authorization program has returned, check the signature again.
  check_p3d_signature();
}

/**
 * Stops the instance (if it is running) and deletes any packages referenced
 * by the instance.  This is normally called by JavaScript, via
 * P3DMainObject::call_uninstall().
 */
bool P3DInstance::
uninstall_packages() {
  if (_packages.empty()) {
    // If we have no packages (for instance, because we're untrusted), we
    // can't uninstall anything.
    nout << "Uninstall failed: no packages.\n";
    return false;
  }

  nout << "Uninstalling " << _packages.size() << " packages\n";

  Packages::const_iterator pi;
  for (pi = _packages.begin(); pi != _packages.end(); ++pi) {
    P3DPackage *package = (*pi);
    if (package != _image_package && package != _certlist_package &&
        package != _p3dcert_package) {
      package->uninstall();
    }
  }

  // Also clean up the start directory, if we have a custom start dir.  We
  // won't do this if verify_contents is 'none'.
  P3DInstanceManager *inst_mgr = P3DInstanceManager::get_global_ptr();
  if (inst_mgr->get_verify_contents() != P3D_VC_never) {
    string start_dir_suffix = get_start_dir_suffix();
    if (!start_dir_suffix.empty()) {
      string start_dir = inst_mgr->get_start_dir() + start_dir_suffix;
      nout << "Cleaning up start directory " << start_dir << "\n";
      inst_mgr->delete_directory_recursively(start_dir);
    }
  }

  return true;
}

/**
 * Stops the instance (if it is running) and deletes all packages downloaded
 * from any of the host(s) referenced by the instance.  This is a more
 * aggressive uninstall than uninstall_packages().  This is normally called by
 * JavaScript, via P3DMainObject::call_uninstall().
 */
bool P3DInstance::
uninstall_host() {
  if (_packages.empty()) {
    // If we have no packages (for instance, because we're untrusted), we
    // can't uninstall anything.
    nout << "Uninstall failed: no packages.\n";
    return false;
  }

  uninstall_packages();

  // Collect the set of hosts referenced by this instance.
  set<P3DHost *> hosts;
  Packages::const_iterator pi;
  for (pi = _packages.begin(); pi != _packages.end(); ++pi) {
    P3DPackage *package = (*pi);
    if (package != _image_package && package != _certlist_package &&
        package != _p3dcert_package) {
      hosts.insert(package->get_host());
    }
  }
  nout << "Uninstalling " << hosts.size() << " hosts\n";

  // Uninstall all of them.
  set<P3DHost *>::iterator hi;
  for (hi = hosts.begin(); hi != hosts.end(); ++hi) {
    P3DHost *host = (*hi);
    host->uninstall();
  }

  return true;
}

/**
 * The private implementation of set_p3d_filename(), this does all the work
 * except for updating p3d_basename.  It is intended to be called internally,
 * and might be passed a temporary filename.
 */
void P3DInstance::
priv_set_p3d_filename(const string &p3d_filename, const int &p3d_offset) {
  if (!_fparams.get_p3d_filename().empty()) {
    nout << "p3d_filename already set to: " << _fparams.get_p3d_filename()
         << ", trying to set to " << p3d_filename << "\n";
    return;
  }

  _fparams.set_p3d_filename(p3d_filename);
  // The default for p3d_offset is -1, which means not to change it.
  if (p3d_offset >= 0) {
    _fparams.set_p3d_offset(p3d_offset);
  }
  _got_fparams = true;

  _main_object->set_float_property("instanceDownloadProgress", 1.0);

  // Generate a special notification: onpluginload, indicating the plugin has
  // read its parameters and is ready to be queried (even if Python has not
  // yet started).
  send_notify("onpluginload");

  if (!_mf_reader.open_read(_fparams.get_p3d_filename(), _fparams.get_p3d_offset())) {
    if (_fparams.get_p3d_offset() == 0) {
      nout << "Couldn't read " << _fparams.get_p3d_filename() << "\n";
    } else {
      nout << "Couldn't read " << _fparams.get_p3d_filename()
           << " at offset " << _fparams.get_p3d_offset() << "\n";
    }
    set_failed();
    return;
  }

  check_p3d_signature();
}

/**
 * Determines _p3d_basename from the indicated URL.
 */
void P3DInstance::
determine_p3d_basename(const string &p3d_url) {
  string file_part = p3d_url;
  size_t question = file_part.find('?');
  if (question != string::npos) {
    file_part = file_part.substr(0, question);
  }
  size_t slash = file_part.rfind('/');
  if (slash != string::npos) {
    file_part = file_part.substr(slash + 1);
  }
  _p3d_basename = file_part;

  nout << "p3d_basename = " << _p3d_basename << "\n";
}

/**
 * Returns true if the indicated origin_match string, one of either run_origin
 * or script_origin from the p3d_info.xml file, matches the origin of the page
 * that embedded the p3d file.
 */
bool P3DInstance::
check_matches_origin(const string &origin_match) {
  // First, separate the string up at the semicolons.
  size_t p = 0;
  size_t semicolon = origin_match.find(';');
  while (semicolon != string::npos) {
    if (check_matches_origin_one(origin_match.substr(p, semicolon - p))) {
      return true;
    }
    p = semicolon + 1;
    semicolon = origin_match.find(';', p);
  }
  if (check_matches_origin_one(origin_match.substr(p))) {
    return true;
  }

  // It doesn't match any of the semicolon-delimited strings within
  // origin_match.
  return false;
}

/**
 * Called for each semicolon-delimited string within origin_match passed to
 * check_matches_origin().
 */
bool P3DInstance::
check_matches_origin_one(const string &origin_match) {
  // Do we have a protocol?
  size_t p = 0;
  size_t colon = origin_match.find(':');
  if (colon + 1 < origin_match.length() && origin_match[colon + 1] == '/') {
    // Yes.  It should therefore match the protocol we have in the origin.
    string protocol = origin_match.substr(0, colon + 1);
    if (!check_matches_component(_origin_protocol, protocol)) {
      return false;
    }
    p = colon + 2;
    // We'll support both http:hostname and http:hostname, in case the user is
    // sloppy.
    if (p < origin_match.length() && origin_match[p] == '/') {
      ++p;
    }
    colon = origin_match.find(':', p);
  }

  // Do we have a port?
  if (colon < origin_match.length() && isdigit(origin_match[colon + 1])) {
    // Yes.  It should therefore match the port we have in the origin.
    string port = origin_match.substr(colon + 1);
    if (!check_matches_component(_origin_port, port)) {
      return false;
    }
  }

  // The hostname should also match what we have in the origin.
  string hostname = origin_match.substr(p, colon - p);
  if (!check_matches_hostname(_origin_hostname, hostname)) {
    return false;
  }

  // Everything matches.
  return true;
}

/**
 * Matches the hostname of check_matches_origin: the individual components of
 * the hostname are matched independently, with '**.' allowed at the beginning
 * to indicate zero or more prefixes.  Returns true on match, false on
 * failure.
 */
bool P3DInstance::
check_matches_hostname(const string &orig, const string &match) {
  // First, separate both strings up at the dots.
  vector<string> orig_components;
  separate_components(orig_components, orig);

  vector<string> match_components;
  separate_components(match_components, match);

  // If the first component of match is "**", it means we accept any number,
  // zero or more, of components at the beginning of the hostname.
  if (!match_components.empty() && match_components[0] == "**") {
    // Remove the leading "**"
    match_components.erase(match_components.begin());
    // Then remove any extra components from the beginning of orig_components;
    // we won't need to check them.
    if (orig_components.size() > match_components.size()) {
      size_t num_to_remove = orig_components.size() - match_components.size();
      orig_components.erase(orig_components.begin(), orig_components.begin() + num_to_remove);
    }
  }

  // Now match the remaining components one-to-one.
  if (match_components.size() != orig_components.size()) {
    return false;
  }

  vector<string>::const_iterator p = orig_components.begin();
  vector<string>::const_iterator p2 = match_components.begin();

  while (p != orig_components.end()) {
    assert(p2 != match_components.end());
    if (!check_matches_component(*p, *p2)) {
      return false;
    }
    ++p;
    ++p2;
  }

  assert(p2 == match_components.end());
  return true;
}

/**
 * Separates the indicated hostname into its components at the dots.
 */
void P3DInstance::
separate_components(vector<string> &components, const string &str) {
  size_t p = 0;
  size_t dot = str.find('.');
  while (dot != string::npos) {
    components.push_back(str.substr(p, dot - p));
    p = dot + 1;
    dot = str.find('.', p);
  }
  components.push_back(str.substr(p));
}

/**
 * Matches a single component of check_matches_origin: either protocol or
 * port, or a single component of the hostname.  Case-insensitive, and
 * supports the '*' wildcard operator to match the entire component.  Returns
 * true on match, false on failure.
 */
bool P3DInstance::
check_matches_component(const string &orig, const string &match) {
  if (match == "*") {
    return true;
  }

  // Case-insensitive compare.
  if (orig.length() != match.length()) {
    return false;
  }

  string::const_iterator p = orig.begin();
  string::const_iterator p2 = match.begin();

  while (p != orig.end()) {
    assert(p2 != match.end());
    if (tolower(*p) != tolower(*p2)) {
      return false;
    }
    ++p;
    ++p2;
  }

  assert(p2 == match.end());
  return true;
}

/**
 * Checks the signature(s) encoded in the p3d file, and looks to see if any of
 * them are recognized.
 *
 * If the signature is recognized, calls mark_p3d_trusted(); otherwise, calls
 * mark_p3d_untrusted().
 */
void P3DInstance::
check_p3d_signature() {
  P3DInstanceManager *inst_mgr = P3DInstanceManager::get_global_ptr();
  if (inst_mgr->get_trusted_environment()) {
    // If we're in a trusted environment (e.g.  the panda3d command line,
    // where we've already downloaded the p3d file separately), then
    // everything is approved.
    mark_p3d_trusted();
    return;
  }

  // See if we've previously approved the certificate--any certificate--that's
  // signing this p3d file.
  int num_signatures = _mf_reader.get_num_signatures();
  for (int i = 0; i < num_signatures; ++i) {
    const P3DMultifileReader::CertChain &chain = _mf_reader.get_signature(i);

    // Here's a certificate that has signed this multifile.
    X509 *cert = chain[0]._cert;

    // Look up the certificate to see if we've stored a copy in our certs dir.
    if (inst_mgr->find_cert(cert)) {
      mark_p3d_trusted();
      return;
    }
  }

  // Check the list of pre-approved certificates.
  if (_certlist_package == NULL) {
    // We have to go download this package.
    P3DInstanceManager *inst_mgr = P3DInstanceManager::get_global_ptr();
    P3DHost *host = inst_mgr->get_host(inst_mgr->get_host_url());
    _certlist_package = host->get_package("certlist", "", "", "");
    if (_certlist_package != NULL) {
      _certlist_package->add_instance(this);
    }

    // When the package finishes downloading, we will come back here.
    return;
  }

  if (!_certlist_package->get_ready() && !_certlist_package->get_failed()) {
    // Wait for it to finish downloading.
    return;
  }

  // Couldn't find any approved certificates.
  mark_p3d_untrusted();
  return;
}

/**
 * This is called internally when it has been determined that the p3d file
 * can't (yet) be trusted, for instance because it lacks a signature, or
 * because it is signed by an unrecognized certificate.  This puts up the red
 * "auth" button and waits for the user to approve the app before continuing.
 */
void P3DInstance::
mark_p3d_untrusted() {
  // Failed test.
  nout << "p3d untrusted\n";
  if (is_failed()) {
    return;
  }

  if (_p3dcert_package == NULL) {
    // We have to go download this package.
    P3DInstanceManager *inst_mgr = P3DInstanceManager::get_global_ptr();
    P3DHost *host = inst_mgr->get_host(inst_mgr->get_host_url());
    _p3dcert_package = host->get_package("p3dcert", "", "", "");
    if (_p3dcert_package != NULL) {
      _p3dcert_package->add_instance(this);
    }

    // When the package finishes downloading, we will come back here.
    return;
  }

  if (_p3dcert_package->get_failed()) {
    // Oh, too bad for us.  We're dependent on this package which we weren't
    // able to download for some reason.
    set_failed();
  }

  if (!_p3dcert_package->get_ready()) {
    // Wait for it to finish downloading.
    return;
  }

  // OK, we've got the authorization program; we can put up the red button
  // now.

  // Notify JS that we've got no trust of the p3d file.
  _main_object->set_bool_property("trusted", false);
  send_notify("onunauth");
  set_background_image(IT_unauth);
  set_button_image(IT_auth_ready);
  make_splash_window();
}

/**
 * This is called internally when it has been determined that the p3d file can
 * be trusted and started.  When this is called, the p3d file will be examined
 * and made ready to start; it will not be started until this is called.
 */
void P3DInstance::
mark_p3d_trusted() {
  nout << "p3d trusted\n";
  // Only call this once.
  if (_p3d_trusted) {
    nout << "mark_p3d_trusted() called twice on " << _fparams.get_p3d_filename()
         << "\n";
    return;
  }

  // Extract the application desc file from the p3d file.
  stringstream sstream;
  if (!_mf_reader.extract_one(sstream, "p3d_info.xml")) {
    nout << "No p3d_info.xml file found in " << _fparams.get_p3d_filename() << "\n";
    set_failed();

  } else {
    sstream.seekg(0);
    TiXmlDocument doc;
    sstream >> doc;

    scan_app_desc_file(&doc);
  }

  // Now we've got no further need to keep the _mf_reader open.
  _mf_reader.close();

  // For the moment, all sessions will be unique.  TODO: support multiple
  // instances per session.
  P3DInstanceManager *inst_mgr = P3DInstanceManager::get_global_ptr();
  ostringstream strm;
  strm << inst_mgr->get_unique_id();
  _session_key = strm.str();

  // Notify JS that we've accepted the trust of the p3d file.
  _main_object->set_bool_property("trusted", true);
  send_notify("onauth");

  // Now that we're all set up, grab the panda3d package.  We need to examine
  // this before we can start to download the remaining packages.
  add_panda3d_package();
}

/**
 * Reads the p3d_info.xml file at instance startup, to determine the set of
 * required packages and so forth.
 */
void P3DInstance::
scan_app_desc_file(TiXmlDocument *doc) {
  P3DInstanceManager *inst_mgr = P3DInstanceManager::get_global_ptr();

  TiXmlElement *xpackage = doc->FirstChildElement("package");
  if (xpackage == NULL) {
    return;
  }
  assert(_xpackage == NULL);
  _xpackage = (TiXmlElement *)xpackage->Clone();

  TiXmlElement *xconfig = _xpackage->FirstChildElement("config");
  if (xconfig != NULL) {
    int hidden = 0;
    if (xconfig->QueryIntAttribute("hidden", &hidden) == TIXML_SUCCESS) {
      if (hidden != 0) {
        _hidden = true;
      }
    }

    const char *log_basename = xconfig->Attribute("log_basename");
    if (log_basename != NULL) {
      _log_basename = log_basename;
    }

    const char *prc_name = xconfig->Attribute("prc_name");
    if (prc_name != NULL) {
      _prc_name = prc_name;
    }

    const char *start_dir = xconfig->Attribute("start_dir");
    if (start_dir != NULL) {
      _start_dir = start_dir;
    }

    const char *run_origin = xconfig->Attribute("run_origin");
    if (run_origin != NULL) {
      _matches_run_origin = check_matches_origin(run_origin);
    }

    const char *script_origin = xconfig->Attribute("script_origin");
    if (script_origin != NULL) {
      _matches_script_origin = check_matches_origin(script_origin);
    }

    int allow_python_dev = 0;
    if (xconfig->QueryIntAttribute("allow_python_dev", &allow_python_dev) == TIXML_SUCCESS) {
      _allow_python_dev = (allow_python_dev != 0);
    }

    int keep_user_env = 0;
    if (xconfig->QueryIntAttribute("keep_user_env", &keep_user_env) == TIXML_SUCCESS) {
      _keep_user_env = (keep_user_env != 0);
    }

    int auto_start = 0;
    if (xconfig->QueryIntAttribute("auto_start", &auto_start) == TIXML_SUCCESS) {
      _auto_start = (auto_start != 0);
    }

    int auto_install = 0;
    if (xconfig->QueryIntAttribute("auto_install", &auto_install) == TIXML_SUCCESS) {
      _auto_install = (auto_install != 0);
    }
  }

  nout << "_matches_run_origin = " << _matches_run_origin << "\n";
  nout << "_matches_script_origin = " << _matches_script_origin << "\n";

  if (inst_mgr->get_trusted_environment()) {
    // If we're in a trusted environment, it is as if the origin always
    // matches.
    _matches_run_origin = true;
    _matches_script_origin = true;
  }

  if (_auth_button_clicked) {
    // But finally, if the user has already clicked through the red "auth"
    // button, no need to present himher with another green "play" button as
    // well.
    _auto_install = true;
    _auto_start = true;
  }

  nout << "_auto_install = " << _auto_install
       << ", _auto_start = " << _auto_start
       << ", _stop_on_ready = " << _stop_on_ready
       << "\n";

  if (_hidden && _got_wparams) {
    _wparams.set_window_type(P3D_WT_hidden);
  }

  if (!_matches_run_origin) {
    nout << "Cannot run " << _p3d_basename << " from origin "
         << _origin_protocol << "//" << _origin_hostname
         << ":" << _origin_port << "\n";
    set_failed();
  }
}

/**
 * Adds the "panda3d" package only.  This package must be downloaded first,
 * and its desc file examined, before we can begin downloading the other
 * packages.
 */
void P3DInstance::
add_panda3d_package() {
  assert(!_packages_specified);
  assert(_panda3d_package == NULL);
  if (_xpackage == NULL) {
    return;
  }

  P3DInstanceManager *inst_mgr = P3DInstanceManager::get_global_ptr();

  TiXmlElement *xrequires = _xpackage->FirstChildElement("requires");
  while (xrequires != NULL) {
    const char *name = xrequires->Attribute("name");
    const char *host_url = xrequires->Attribute("host");
    if (name != NULL && host_url != NULL && strcmp(name, "panda3d") == 0) {
      const char *version = xrequires->Attribute("version");
      if (version == NULL) {
        version = "";
      }
      const char *seq = xrequires->Attribute("seq");
      if (seq == NULL) {
        seq = "";
      }
      P3DHost *host = inst_mgr->get_host(host_url);
      add_package(name, version, seq, host);
      return;
    }

    xrequires = xrequires->NextSiblingElement("requires");
  }

  nout << "No panda3d package found in " << _fparams.get_p3d_filename() << "\n";
  set_failed();
}

/**
 * Adds the set of packages required by this p3d file to the _packages member.
 * If _auto_install is true, this will also start downloading them.
 */
void P3DInstance::
add_packages() {
  assert(!_packages_specified);
  if (_xpackage == NULL) {
    return;
  }

  P3DInstanceManager *inst_mgr = P3DInstanceManager::get_global_ptr();

  TiXmlElement *xrequires = _xpackage->FirstChildElement("requires");
  while (xrequires != NULL) {
    const char *name = xrequires->Attribute("name");
    const char *host_url = xrequires->Attribute("host");
    if (name != NULL && host_url != NULL) {
      const char *version = xrequires->Attribute("version");
      if (version == NULL) {
        version = "";
      }
      const char *seq = xrequires->Attribute("seq");
      if (seq == NULL) {
        seq = "";
      }
      P3DHost *host = inst_mgr->get_host(host_url);
      add_package(name, version, seq, host);
    }

    xrequires = xrequires->NextSiblingElement("requires");
  }

  _packages_specified = true;

  consider_start_download();

  // Now that we've scanned the p3d file, and prepared the list of packages,
  // it's safe to set the trusted flag.
  _p3d_trusted = true;

  // If the packages are already downloaded, start the instance rolling.
  if (get_packages_ready()) {
    mark_download_complete();
  }
}


/**
 * Looks in the p3d_info.xml file for the alt_host associated with the
 * indicated host_url, if any.  Returns empty string if there is no match.
 */
string P3DInstance::
find_alt_host_url(const string &host_url, const string &alt_host) {
  TiXmlElement *xhost = _xpackage->FirstChildElement("host");
  while (xhost != NULL) {
    const char *url = xhost->Attribute("url");
    if (url != NULL && host_url == url) {
      // This matches the host.  Now do we have a matching alt_host keyword
      // for this host?
      TiXmlElement *xalt_host = xhost->FirstChildElement("alt_host");
      while (xalt_host != NULL) {
        const char *keyword = xalt_host->Attribute("keyword");
        if (keyword != NULL && alt_host == keyword) {
          const char *alt_host_url = xalt_host->Attribute("url");
          if (alt_host_url != NULL) {
            return alt_host_url;
          }
        }
        xalt_host = xalt_host->NextSiblingElement("alt_host");
      }
    }
    xhost = xhost->NextSiblingElement("host");
  }

  return string();
}

/**
 * Looks in the p3d_info.xml file for the auxiliary host information for the
 * selected host.  Some of this information is helpful to have before the host
 * has read its own contents.xml file (particularly the host_dir
 * specification).
 */
void P3DInstance::
get_host_info(P3DHost *host) {
  // We should only call this function if we haven't already read the host's
  // more-authoritative contents.xml file.
  assert(!host->has_contents_file());

  TiXmlElement *xhost = _xpackage->FirstChildElement("host");
  while (xhost != NULL) {
    const char *url = xhost->Attribute("url");
    if (url != NULL && host->get_host_url() == url) {
      // Found the entry for this particular host.
      host->read_xhost(xhost);
      return;
    }
    xhost = xhost->NextSiblingElement("host");
  }

  // Didn't find an entry for this host; oh well.
}

/**
 * Determines the local path to the appropriate start directory for this
 * instance, within the generic "start" directory.  Returns empty string if
 * this instance doesn't specify a custom start directory.
 *
 * If this is nonempty, it will begin with a slash--the intention is to append
 * this to the end of the generic start_dir path.
 */
string P3DInstance::
get_start_dir_suffix() const {
  string start_dir_suffix;

  string start_dir = get_fparams().lookup_token("start_dir");
  if (start_dir.empty()) {
    start_dir = _start_dir;

    if (!start_dir.empty()) {
      // If the start_dir is taken from the p3d file (and not from the HTML
      // tokens), then we also append the alt_host name to the start_dir, so
      // that each alt_host variant will run in a different directory.
      string alt_host = get_fparams().lookup_token("alt_host");
      if (!alt_host.empty()) {
        start_dir += "_";
        start_dir += alt_host;
      }
    }
  }
  if (!start_dir.empty()) {
    P3DInstanceManager *inst_mgr = P3DInstanceManager::get_global_ptr();
    inst_mgr->append_safe_dir(start_dir_suffix, start_dir);
  }

  return start_dir_suffix;
}

/**
 * Sends the XML sequence to inform the session of our browser's toplevel
 * window object.
 */
void P3DInstance::
send_browser_script_object() {
  TiXmlDocument *doc = new TiXmlDocument;
  TiXmlElement *xcommand = new TiXmlElement("command");
  xcommand->SetAttribute("cmd", "pyobj");
  xcommand->SetAttribute("op", "set_browser_script_object");
  if (_dom_object != NULL) {
    xcommand->LinkEndChild(_session->p3dobj_to_xml(_dom_object));
  }

  doc->LinkEndChild(xcommand);

  _session->send_command(doc);
}

/**
 * Creates a new P3D_request structure from the XML. Returns NULL if no
 * request is needed.
 */
P3D_request *P3DInstance::
make_p3d_request(TiXmlElement *xrequest) {
  P3DInstanceManager *inst_mgr = P3DInstanceManager::get_global_ptr();
  P3D_request *request = NULL;

  const char *rtype = xrequest->Attribute("rtype");
  if (rtype != NULL) {
    if (strcmp(rtype, "notify") == 0) {
      const char *message = xrequest->Attribute("message");
      if (message != NULL) {
        // A notify message from Python code.
        request = new P3D_request;
        request->_instance = NULL;
        request->_request_type = P3D_RT_notify;
        request->_request._notify._message = strdup(message);
        handle_notify_request(message);
      }

    } else if (strcmp(rtype, "script") == 0) {
      // We don't actually build a P3D_request for a script request; we always
      // just handle it immediately.
      const char *operation = xrequest->Attribute("operation");
      TiXmlElement *xobject = xrequest->FirstChildElement("object");
      const char *property_name = xrequest->Attribute("property_name");
      int needs_response = 0;
      xrequest->Attribute("needs_response", &needs_response);
      int unique_id = 0;
      xrequest->Attribute("unique_id", &unique_id);

      P3D_object *value = NULL;
      TiXmlElement *xvalue = xrequest->FirstChildElement("value");
      if (xvalue != NULL) {
        value = _session->xml_to_p3dobj(xvalue);
      }
      if (value == NULL) {
        value = inst_mgr->new_none_object();
      }

      if (operation != NULL && xobject != NULL) {
        P3D_object *object = _session->xml_to_p3dobj(xobject);

        if (property_name == NULL) {
          property_name = "";
        }

        handle_script_request(operation, object, property_name, value,
                              (needs_response != 0), unique_id);
      }

      P3D_OBJECT_DECREF(value);

    } else if (strcmp(rtype, "drop_p3dobj") == 0) {
      int object_id;
      if (xrequest->QueryIntAttribute("object_id", &object_id) == TIXML_SUCCESS) {
        // We no longer need to keep this reference.
        _session->drop_p3dobj(object_id);
      }

    } else if (strcmp(rtype, "stop") == 0) {
      // A stop request from Python code.  This is kind of weird, but OK.
      request = new P3D_request;
      request->_instance = NULL;
      request->_request_type = P3D_RT_stop;

    } else if (strcmp(rtype, "forget_package") == 0) {
      const char *host_url = xrequest->Attribute("host_url");
      if (host_url != NULL) {
        // A Python-level request to remove a package from the cache.
        request = new P3D_request;
        request->_instance = NULL;
        request->_request_type = P3D_RT_forget_package;
        request->_request._forget_package._host_url = strdup(host_url);
        request->_request._forget_package._package_name = NULL;
        request->_request._forget_package._package_version = NULL;

        const char *package_name = xrequest->Attribute("package_name");
        const char *package_version = xrequest->Attribute("package_version");
        if (package_name != NULL) {
          request->_request._forget_package._package_name = strdup(package_name);
          if (package_version != NULL) {
            request->_request._forget_package._package_version = strdup(package_version);
          }
        }
      }

    } else {
      nout << "Ignoring request of type " << rtype << "\n";
    }
  }

  if (request != NULL) {
    assert(request->_instance == NULL);
    request->_instance = this;
    ref();
  }
  return request;
}

/**
 * Called (in the main thread) when a notify request is received from the
 * subprocess.
 */
void P3DInstance::
handle_notify_request(const string &message) {
  // We look for certain notify events that have particular meaning to this
  // instance.
  if (message == "onpythonload") {
    // Once Python is up and running, we can get the actual main object from
    // the Python side, and merge it with our own.

    TiXmlDocument *doc = new TiXmlDocument;
    TiXmlElement *xcommand = new TiXmlElement("command");
    xcommand->SetAttribute("cmd", "pyobj");
    xcommand->SetAttribute("op", "get_panda_script_object");
    doc->LinkEndChild(xcommand);
    TiXmlDocument *response = _session->command_and_response(doc);

    P3D_object *result = NULL;
    if (response != NULL) {
      TiXmlElement *xresponse = response->FirstChildElement("response");
      if (xresponse != NULL) {
        TiXmlElement *xvalue = xresponse->FirstChildElement("value");
        if (xvalue != NULL) {
          result = _session->xml_to_p3dobj(xvalue);
        }
      }
      delete response;
    }

    if (result != NULL) {
      if (_matches_script_origin) {
        // We only actually merge the objects if this web page is allowed to
        // call our scripting functions.
        _main_object->set_pyobj(result);
      } else {
        // Otherwise, we just do a one-time application of the toplevel
        // properties down to Python.
        _main_object->apply_properties(result);
      }
      P3D_OBJECT_DECREF(result);
    }

    _main_object->set_string_property("status", "starting");

  } else if (message == "onwindowopen") {
    // The process told us that it just successfully opened its window, for
    // the first time.  Hide the splash window.
    _instance_window_opened = true;
    if (_splash_window != NULL) {
      _splash_window->set_visible(false);
    }

    // Guess we won't be using (most of) these images any more.
    for (int i = 0; i < (int)IT_num_image_types; ++i) {
      if (i != IT_active) {
        _image_files[i].cleanup();
      }
    }

    _main_object->set_string_property("status", "open");

  } else if (message == "onwindowattach") {
    // The graphics window has been attached to the browser frame (maybe
    // initially, maybe later).  Hide the splash window.

    // We don't actually hide the splash window immediately on OSX, because on
    // that platform, we can hide it as soon as we render the first frame,
    // avoiding an empty frame in that little period of time between the
    // window opening and the first frame being drawn.
    _instance_window_attached = true;
#ifndef __APPLE__
    if (_splash_window != NULL) {
      _splash_window->set_visible(false);
    }
#endif  // __APPLE__

#ifdef __APPLE__
    // Start a timer to update the frame repeatedly.  This seems to be
    // steadier than waiting for nullEvent.
    if (_frame_timer == NULL) {
      CFRunLoopTimerContext timer_context;
      memset(&timer_context, 0, sizeof(timer_context));
      timer_context.info = this;
      _frame_timer = CFRunLoopTimerCreate
        (NULL, 0, 1.0 / 60.0, 0, 0, timer_callback, &timer_context);
      CFRunLoopRef run_loop = CFRunLoopGetCurrent();
      CFRunLoopAddTimer(run_loop, _frame_timer, kCFRunLoopCommonModes);
    }
#endif  // __APPLE__

  } else if (message == "onwindowdetach") {
    // The graphics window has been removed from the browser frame.  Restore
    // the splash window.
    _instance_window_opened = true;
    _instance_window_attached = false;
    set_background_image(IT_active);
    if (_splash_window != NULL) {
      _splash_window->set_visible(true);
    }

#ifdef __APPLE__
    // Stop the frame timer; we don't need it any more.
    if (_frame_timer != NULL) {
      CFRunLoopTimerInvalidate(_frame_timer);
      CFRelease(_frame_timer);
      _frame_timer = NULL;
    }
#endif  // __APPLE__

  } else if (message == "buttonclick") {
    // We just got a special "button click" message from the sub-thread.  This
    // case is a little unusual, as it came from the splash window and not
    // from Python (we presumably haven't even started Python yet).  We use
    // this as a sneaky way to forward the event from the sub-thread to the
    // main thread.
    splash_button_clicked_main_thread();

  } else if (message == "authfinished") {
    // Similarly for the "auth finished" message.
    auth_finished_main_thread();

  } else if (message == "keyboardfocus") {
    if (_splash_window != NULL) {
      _splash_window->request_keyboard_focus();
    }
  }
}

/**
 * Called (in the main thread) when a script request is received from the
 * subprocess.
 */
void P3DInstance::
handle_script_request(const string &operation, P3D_object *object,
                      const string &property_name, P3D_object *value,
                      bool needs_response, int unique_id) {

  TiXmlDocument *doc = new TiXmlDocument;
  TiXmlElement *xcommand = new TiXmlElement("command");
  xcommand->SetAttribute("cmd", "script_response");
  xcommand->SetAttribute("unique_id", unique_id);

  doc->LinkEndChild(xcommand);

  if (operation == "get_property") {
    P3D_object *result = P3D_OBJECT_GET_PROPERTY(object, property_name.c_str());

    // We've got the property value; feed it back down to the subprocess.

    if (result != NULL) {
      xcommand->LinkEndChild(_session->p3dobj_to_xml(result));
      P3D_OBJECT_DECREF(result);
    }

  } else if (operation == "set_property") {
    bool result =
      P3D_OBJECT_SET_PROPERTY(object, property_name.c_str(), true, value);

    TiXmlElement *xvalue = new TiXmlElement("value");
    xvalue->SetAttribute("type", "bool");
    xvalue->SetAttribute("value", (int)result);
    xcommand->LinkEndChild(xvalue);

  } else if (operation == "del_property") {
    bool result = P3D_OBJECT_SET_PROPERTY(object, property_name.c_str(), true, NULL);

    TiXmlElement *xvalue = new TiXmlElement("value");
    xvalue->SetAttribute("type", "bool");
    xvalue->SetAttribute("value", (int)result);
    xcommand->LinkEndChild(xvalue);

  } else if (operation == "has_method") {
    bool result = P3D_OBJECT_HAS_METHOD(object, property_name.c_str());

    TiXmlElement *xvalue = new TiXmlElement("value");
    xvalue->SetAttribute("type", "bool");
    xvalue->SetAttribute("value", (int)result);
    xcommand->LinkEndChild(xvalue);

  } else if (operation == "call") {
    // Convert the single value parameter into an array of parameters.
    P3D_object **values = &value;
    int num_values = 1;
    if (value->_class == &P3DObject::_object_class) {
      P3DObject *p3dobj = (P3DObject *)value;
      if (p3dobj->get_object_array_size() != -1) {
        values = p3dobj->get_object_array();
        num_values = p3dobj->get_object_array_size();
      }
    }

    P3D_object *result =
      P3D_OBJECT_CALL(object, property_name.c_str(), needs_response,
                      values, num_values);

    if (result != NULL) {
      xcommand->LinkEndChild(_session->p3dobj_to_xml(result));
      P3D_OBJECT_DECREF(result);
    }

  } else if (operation == "eval") {
    P3D_object *result;
    int size = P3D_OBJECT_GET_STRING(value, NULL, 0);
    char *buffer = new char[size + 1];
    P3D_OBJECT_GET_STRING(value, buffer, size + 1);
    result = P3D_OBJECT_EVAL(object, buffer);
    delete[] buffer;

    if (result != NULL) {
      xcommand->LinkEndChild(_session->p3dobj_to_xml(result));
      P3D_OBJECT_DECREF(result);
    }
  }

  if (needs_response) {
    _session->send_command(doc);
  } else {
    delete doc;
  }
}

/**
 * Sets the "failed" indication to display sadness to the user--we're unable
 * to launch the instance for some reason.
 */
void P3DInstance::
set_failed() {
  set_button_image(IT_none);
  set_background_image(IT_failed);
  _main_object->set_string_property("status", "failed");

  if (!_failed) {
    _failed = true;
    make_splash_window();
    send_notify("onfail");
  }
}

/**
 * Creates the splash window to be displayed at startup, if it's time.
 */
void P3DInstance::
make_splash_window() {
  // Should we make the splash window visible?
  bool make_visible = true;
  if (_instance_window_opened) {
    // Not once we've opened the main window.
    make_visible = false;
  }

  if (_wparams.get_window_type() != P3D_WT_embedded &&
      !_stuff_to_download && _auto_install &&
      (_auto_start || _stop_on_ready) && _p3d_trusted) {
    // If it's a toplevel or fullscreen window, then we don't want a splash
    // window unless we have stuff to download, or a button to display.
    make_visible = false;
  }

  if (is_failed()) {
    // But, if we've failed to launch somehow, we need to let the user know.
    make_visible = true;
  }

  if (_splash_window != NULL) {
    // Already got one.
    _splash_window->set_visible(make_visible);
    return;
  }
  if (!_got_wparams) {
    // Don't know where to put it yet.
    return;
  }
  if (_wparams.get_window_type() == P3D_WT_hidden && !is_failed()) {
    // We're hidden, and so is the splash window.  (But if we've got a failure
    // case to report, we don't care and create the splash window anyway.)
    return;
  }

  _splash_window = new SplashWindowType(this, make_visible);

  // Get the splash window colors.  We must set these *before* we call
  // set_wparams.
  if (_fparams.has_token("fgcolor")) {
    int r, g, b;
    if (parse_color(r, g, b, _fparams.lookup_token("fgcolor"))) {
      _splash_window->set_fgcolor(r, g, b);
    } else {
      nout << "parse failure on fgcolor " << _fparams.lookup_token("fgcolor") << "\n";
    }
  }
  if (_fparams.has_token("bgcolor")) {
    int r, g, b;
    if (parse_color(r, g, b, _fparams.lookup_token("bgcolor"))) {
      _splash_window->set_bgcolor(r, g, b);
      _splash_window->set_bar_bgcolor(r, g, b);
    } else {
      nout << "parse failure on bgcolor " << _fparams.lookup_token("bgcolor") << "\n";
    }
  }
  if (_fparams.has_token("barcolor")) {
    int r, g, b;
    if (parse_color(r, g, b, _fparams.lookup_token("barcolor"))) {
      _splash_window->set_barcolor(r, g, b);
    } else {
      nout << "parse failure on barcolor " << _fparams.lookup_token("barcolor") << "\n";
    }
  }
  if (_fparams.has_token("bar_bgcolor")) {
    int r, g, b;
    if (parse_color(r, g, b, _fparams.lookup_token("bar_bgcolor"))) {
      _splash_window->set_bar_bgcolor(r, g, b);
    } else {
      nout << "parse failure on bar_bgcolor " << _fparams.lookup_token("bar_bgcolor") << "\n";
    }
  }
  if (_fparams.has_token("bar_border")) {
    int border = _fparams.lookup_token_int("bar_border");
    _splash_window->set_bar_border(border);
  }
  if (_fparams.has_token("bar_bottom")) {
    int bottom = _fparams.lookup_token_int("bar_bottom");
    _splash_window->set_bar_bottom(bottom);
  }
  if (_fparams.has_token("bar_width")) {
    string bar_width = _fparams.lookup_token("bar_width");
    char *endptr;
    long width = strtol(bar_width.c_str(), &endptr, 10);
    bool percent = false;

    if (*endptr == '%') {
      percent = true;
      ++endptr;
    }
    if (*endptr == '\0' && width >= 0 && width < 65536) {
      _splash_window->set_bar_width((int)width, percent);
    } else {
      nout << "parse failure on bar_width " << bar_width << "\n";
    }
  }
  if (_fparams.has_token("bar_height")) {
    string bar_height = _fparams.lookup_token("bar_height");
    char *endptr;
    long height = strtol(bar_height.c_str(), &endptr, 10);
    bool percent = false;

    if (*endptr == '%') {
      percent = true;
      ++endptr;
    }
    if (*endptr == '\0' && height >= 0 && height < 65536) {
      _splash_window->set_bar_height((int)height, percent);
    } else {
      nout << "parse failure on bar_height " << bar_height << "\n";
    }
  }
  if (_fparams.has_token("font_family")) {
    string family = _fparams.lookup_token("font_family");
    _splash_window->set_font_family(family);
  }
  if (_fparams.has_token("font_size")) {
    int size = _fparams.lookup_token_int("font_size");
    _splash_window->set_font_size(size);
  }
  if (_fparams.has_token("font_style")) {
    string style = _fparams.lookup_token("font_style");

    if (style == "normal") {
      _splash_window->set_font_style(P3DSplashWindow::FS_normal);
    } else if (style == "oblique") {
      _splash_window->set_font_style(P3DSplashWindow::FS_oblique);
    } else if (style == "italic") {
      _splash_window->set_font_style(P3DSplashWindow::FS_italic);
    } else {
      nout << "parse_failure on font_style " << style << "\n";
    }
  }
  if (_fparams.has_token("font_weight")) {
    string weight = _fparams.lookup_token("font_weight");

    if (weight == "normal") {
      _splash_window->set_font_weight(400);
    } else if (weight == "bold") {
      _splash_window->set_font_weight(700);
    } else if (weight == "bolder") {
      _splash_window->set_font_weight(700);
    } else if (weight == "lighter") {
      _splash_window->set_font_weight(100);
    } else if (weight.size() == 3 &&
               weight[0] >= '1' && weight[0] <= '9' &&
               weight[1] == '0' && weight[2] == '0') {
      _splash_window->set_font_weight(((int)weight[0] - 48) * 100);
    } else {
      nout << "parse_failure on font_weight " << weight << "\n";
    }
  }

  _splash_window->set_wparams(_wparams);
  _splash_window->set_install_label(_install_label);

  P3DInstanceManager *inst_mgr = P3DInstanceManager::get_global_ptr();

  // Go get the required images.
  for (int i = 0; i < (int)IT_none; ++i) {
    string token_keyword = string(_image_type_names[i]) + "_img";
    if (!_fparams.has_token(token_keyword) && i < (int)IT_auth_ready) {
      token_keyword = "splash_img";
    }

    string image_url = _fparams.lookup_token(token_keyword);
    if (image_url.empty()) {
      // No specific image for this type is specified; get the default image.
      // We do this via the P3DPackage interface, so we can use the cached
      // version on disk if it's good.
      _image_files[i]._use_standard_image = true;

    } else {
      // We have an explicit image specified for this slot, so just download
      // it directly.  This one won't be cached locally (though the browser
      // might be free to cache it).
      _image_files[i]._use_standard_image = false;
      _image_files[i]._filename.clear();

      // Make a temporary file to receive the splash image.
      assert(_image_files[i]._temp_filename == NULL);
      _image_files[i]._temp_filename = new P3DTemporaryFile(".jpg");

      // Start downloading the requested image.
      ImageDownload *download = new ImageDownload(this, i);
      download->set_url(image_url);
      download->set_filename(_image_files[i]._temp_filename->get_filename());

      start_download(download);
    }
  }

  if (_current_background_image != IT_none) {
    _splash_window->set_image_filename(_image_files[_current_background_image]._filename, P3DSplashWindow::IP_background);
  }

  if (_current_button_image != IT_none) {
    _splash_window->set_image_filename(_image_files[_current_button_image]._filename, P3DSplashWindow::IP_button_ready);
    _splash_window->set_image_filename(_image_files[_current_button_image + 1]._filename, P3DSplashWindow::IP_button_rollover);
    _splash_window->set_image_filename(_image_files[_current_button_image + 2]._filename, P3DSplashWindow::IP_button_click);
    _splash_window->set_button_active(true);
  }
}

/**
 * Specifies the particular image that should be displayed as the background
 * image in the splash window.  Specify IT_none to take the background image
 * away.
 */
void P3DInstance::
set_background_image(ImageType image_type) {
  if (is_failed()) {
    // Can't change the background again after we've failed.
    return;
  }

  if (image_type != _current_background_image) {
    nout << "setting background to " << _image_type_names[image_type]
         << ", splash_window = " << _splash_window << "\n";
    // Remove the previous image.
    _image_files[_current_background_image]._image_placement = P3DSplashWindow::IP_none;

    // Install the new image.
    _current_background_image = image_type;
    if (_current_background_image != IT_none) {
      _image_files[_current_background_image]._image_placement = P3DSplashWindow::IP_background;
    }

    // Update the splash window.
    if (_splash_window != NULL) {
      _splash_window->set_image_filename(_image_files[_current_background_image]._filename, P3DSplashWindow::IP_background);
    }
  }
}

/**
 * Specifies the particular image that should be displayed as the button image
 * in the splash window.  Specify IT_none to take the button image away.
 *
 * This actually defines a trilogy of button images: ready, rollover, click.
 */
void P3DInstance::
set_button_image(ImageType image_type) {
  if (is_failed()) {
    // Can't set the button again after we've failed.
    return;
  }

  if (image_type != _current_button_image) {
    nout << "setting button to " << _image_type_names[image_type] << "\n";
    // Remove the previous image.
    _image_files[_current_button_image]._image_placement = P3DSplashWindow::IP_none;
    if (_current_button_image != IT_none) {
      _image_files[_current_button_image + 1]._image_placement = P3DSplashWindow::IP_none;
      _image_files[_current_button_image + 2]._image_placement = P3DSplashWindow::IP_none;
    }

    // Install the new image.
    _current_button_image = image_type;
    if (_current_button_image != IT_none) {
      _image_files[_current_button_image]._image_placement = P3DSplashWindow::IP_button_ready;
      _image_files[_current_button_image + 1]._image_placement = P3DSplashWindow::IP_button_rollover;
      _image_files[_current_button_image + 2]._image_placement = P3DSplashWindow::IP_button_click;
    }

    // Update the splash window.
    if (_splash_window != NULL) {
      if (_current_button_image != IT_none) {
        _splash_window->set_image_filename(_image_files[_current_button_image]._filename, P3DSplashWindow::IP_button_ready);
        _splash_window->set_image_filename(_image_files[_current_button_image + 1]._filename, P3DSplashWindow::IP_button_rollover);
        _splash_window->set_image_filename(_image_files[_current_button_image + 2]._filename, P3DSplashWindow::IP_button_click);
        _splash_window->set_button_active(true);
      } else {
        _splash_window->set_button_active(false);
      }
    }

  } else {
    // We're not changing the button graphic, but we might be re-activating
    // it.
    if (_splash_window != NULL) {
      if (_current_button_image != IT_none) {
        _splash_window->set_button_active(true);
      } else {
        _splash_window->set_button_active(false);
      }
    }
  }
}

/**
 * Notified when a package information has been successfully downloaded and
 * the package is idle, waiting for activate_download() to be called.
 */
void P3DInstance::
report_package_info_ready(P3DPackage *package) {
  nout << "report_package_info_ready: " << package->get_package_name() << "\n";
  if (package == _image_package || package == _certlist_package ||
      package == _p3dcert_package) {
    // A special case: these packages get immediately downloaded, without
    // waiting for anything else.
    if (package == _certlist_package || package == _p3dcert_package) {
      // If we're downloading one of the two cert packages, though, put up a
      // progress bar.
      make_splash_window();
      if (_splash_window != NULL) {
        _splash_window->set_install_progress(0.0, true, 0);
      }
      if (package == _certlist_package) {
        set_install_label("Getting Certificates");
      } else {
        set_install_label("Getting Authorization Dialog");
      }
    }

    package->activate_download();
    return;
  }

  if (package == _panda3d_package && !_packages_specified) {
    // Another special case.  Once the special panda3d package is ready to
    // download (and we know what platform it belongs to), we can begin to
    // download the remaining required packages.
    string package_platform = package->get_package_platform();
    if (!package_platform.empty() && _session_platform.empty()) {
      // From now on, all platform-specific files downloaded by this session
      // will be for this platform.
      _session_platform = package_platform;
    }
    if (_session_platform != package_platform) {
      nout << "Error: session is " << _session_platform
           << ", but we somehow got panda3d for " << package_platform << "\n";
      set_failed();
      return;
    }

    add_packages();
  }

  // Now that the package's info is ready, we know its set of required
  // packages, and we can add these to the list.
  P3DPackage::Requires::const_iterator ri;
  for (ri = package->_requires.begin(); ri != package->_requires.end(); ++ri) {
    const P3DPackage::RequiredPackage &rp = (*ri);
    add_package(rp._package_name, rp._package_version, rp._package_seq,
                rp._host);
  }

  consider_start_download();
}

/**
 * When all package info files have been obtained, begins downloading stuff.
 */
void P3DInstance::
consider_start_download() {
  if (get_packages_info_ready()) {
    // All packages are ready to go.  Let's start some download action.
    _downloading_packages.clear();
    _prev_downloaded = 0;
    _total_download_size = 0;
    Packages::const_iterator pi;
    for (pi = _packages.begin(); pi != _packages.end(); ++pi) {
      P3DPackage *package = (*pi);
      if (package->get_info_ready()) {
        if (!package->get_ready()) {
          _downloading_packages.push_back(package);
          _total_download_size += package->get_download_size();
        } else {
          _prev_downloaded += package->get_download_size();
        }
      }
    }
    ready_to_install();
  }
}

/**
 * Called when it's time to start the package download process.
 */
void P3DInstance::
ready_to_install() {
  if (_downloading_packages.empty() && _download_complete) {
    // We have already been here.  Ignore it.

  } else if (!_auto_install && !_download_started) {
    // Not authorized to download yet.  We're waiting for the user to
    // acknowledge the download.
    set_background_image(IT_ready);
    set_button_image(IT_play_ready);

  } else {
    _download_started = true;
    _download_complete = false;
    _download_package_index = 0;
    _total_downloaded = 0;

    // Record the time we started the package download, so we can report
    // downloadElapsedTime and predict downloadRemainingTime.
#ifdef _WIN32
    _start_dl_tick = GetTickCount();
#else
    gettimeofday(&_start_dl_timeval, NULL);
#endif

    nout << "Beginning install of " << _downloading_packages.size()
         << " packages, total " << _total_download_size
         << " bytes required (" << _prev_downloaded
         << " previously downloaded).\n";

    if (_downloading_packages.size() > 0) {
      _stuff_to_download = true;

      // Maybe it's time to open a splash window now.
      make_splash_window();
    }

    _main_object->set_string_property("status", "downloading");
    _main_object->set_int_property("numDownloadingPackages", _downloading_packages.size());
    _main_object->set_int_property("totalDownloadSize", _total_download_size);
    _main_object->set_int_property("downloadElapsedSeconds", 0);
    _main_object->set_undefined_property("downloadRemainingSeconds");

    double progress = 0.0;
    if (_prev_downloaded != 0) {
      // We might start off with more than 0 progress, if we've already
      // downloaded some of it previously.
      progress = (_prev_downloaded) / (_total_download_size + _prev_downloaded);
      progress = min(progress, 1.0);

      _main_object->set_float_property("downloadProgress", progress);
    }
    if (_splash_window != NULL) {
      _splash_window->set_install_progress(progress, true, 0);
    }

    send_notify("ondownloadbegin");

    start_next_download();
  }
}

/**
 * Checks whether all packages are ready and waiting to be downloaded; if so,
 * starts the next package in sequence downloading.
 */
void P3DInstance::
start_next_download() {
  while (_download_package_index < (int)_downloading_packages.size()) {
    P3DPackage *package = _downloading_packages[_download_package_index];
    if (package->get_failed()) {
      send_notify("ondownloadfail");
      set_failed();
      return;
    }

    if (!package->get_ready()) {
      // This package is ready to download.  Begin.
      string name = package->get_formatted_name();
      _main_object->set_string_property("downloadPackageName", package->get_package_name());
      _main_object->set_string_property("downloadPackageDisplayName", name);
      _main_object->set_int_property("downloadPackageNumber", _download_package_index + 1);
      _main_object->set_int_property("downloadPackageSize", package->get_download_size());
      set_install_label("Installing " + name);

      nout << "Installing " << package->get_package_name()
           << ", package " << _download_package_index + 1
           << " of " << _downloading_packages.size()
           << ", " << package->get_download_size()
           << " bytes.\n";

      package->activate_download();
      send_notify("ondownloadnext");
      return;
    }

    // This package has been downloaded.  Move to the next.
    _total_downloaded += package->get_download_size();
    ++_download_package_index;
  }

  // Looks like we're all done downloading.  Launch!
  _downloading_packages.clear();

  if (get_packages_ready()) {
    mark_download_complete();
  }
}

/**
 * Called internally when all files needed to launch have been downloaded.
 */
void P3DInstance::
mark_download_complete() {
  if (_failed) {
    return;
  }

  if (!_download_complete) {
    _download_complete = true;
    _main_object->set_bool_property("downloadComplete", true);
    _main_object->set_string_property("status", "downloadcomplete");
    send_notify("ondownloadcomplete");
  }

  // Take down the download progress bar.
  if (_splash_window != NULL) {
    _splash_window->set_install_progress(0.0, true, 0);
  }
  set_install_label("");

  if (_got_wparams && _p3d_trusted) {
    ready_to_start();
  }
}


/**
 * Called internally when we have got the wparams and fparams and we have
 * downloaded all required packages.
 */
void P3DInstance::
ready_to_start() {
  if (_instance_started || is_failed()) {
    // Already started--or never mind.
    return;
  }

  _main_object->set_string_property("status", "ready");
  send_notify("onready");

  P3DInstanceManager *inst_mgr = P3DInstanceManager::get_global_ptr();
  if (_stop_on_ready) {
    // If we've got the "stop_on_ready" token, then exit abruptly now, instead
    // of displaying the splash window.
    request_stop_main_thread();
    return;
  }

  if (_auto_start) {
    set_background_image(IT_launch);
    inst_mgr->start_instance(this);

  } else {
    // We're fully downloaded, and waiting for the user to click play.
    set_background_image(IT_ready);
    set_button_image(IT_play_ready);
  }
}

/**
 * Notified as the instance file is downloaded.
 */
void P3DInstance::
report_instance_progress(double progress, bool is_progress_known,
                         size_t received_data) {
  if (!_show_dl_instance_progress) {
    // If we haven't yet set the download label, set it after a full second
    // has elapsed.  We don't want to set it too soon, because we're not
    // really sure how long it will take to download (the instance file might
    // be already in the browser cache).
#ifdef _WIN32
    int now = GetTickCount();
    double elapsed = (double)(now - _start_dl_tick) * 0.001;
#else
    struct timeval now;
    gettimeofday(&now, NULL);
    double elapsed = (double)(now.tv_sec - _start_dl_timeval.tv_sec) +
      (double)(now.tv_usec - _start_dl_timeval.tv_usec) / 1000000.0;
#endif

    // Put up the progress bar after 2 seconds have elapsed, if we've still
    // got some distance to go; or after 5 seconds have elapsed regardless.
    if ((elapsed > 2.0 && progress < 0.7) ||
        (elapsed > 5.0)) {
      _show_dl_instance_progress = true;
      if (_fparams.has_token("p3d_install_label")) {
        set_install_label(_fparams.lookup_token("p3d_install_label"));
      } else {
        set_install_label("Getting " + _p3d_basename);
      }
    }
  }

  if (_splash_window != NULL && _show_dl_instance_progress) {
    _splash_window->set_install_progress(progress, is_progress_known, received_data);
  }
  _main_object->set_float_property("instanceDownloadProgress", progress);
}

/**
 * Notified as the packages required by the instance file are downloaded.
 */
void P3DInstance::
report_package_progress(P3DPackage *package, double progress) {
  if (package == _image_package) {
    // Ignore this.
    return;
  }
  if (package == _certlist_package || package == _p3dcert_package) {
    // This gets its own progress bar.
    if (_splash_window != NULL) {
      _splash_window->set_install_progress(progress, true, 0);
    }
    return;
  }

  if (_download_package_index >= (int)_downloading_packages.size() ||
      package != _downloading_packages[_download_package_index]) {
    // Quietly ignore a download progress report from an unexpected package.
    return;
  }

  // Scale the progress into the range appropriate to this package.
  progress = (progress * package->get_download_size() + _total_downloaded + _prev_downloaded) / (_total_download_size + _prev_downloaded);
  progress = min(progress, 1.0);

  if (_splash_window != NULL) {
    _splash_window->set_install_progress(progress, true, 0);
  }
  _main_object->set_float_property("downloadProgress", progress);

  static const size_t buffer_size = 256;
  char buffer[buffer_size];

  // Get the floating-point elapsed time.
#ifdef _WIN32
  int now = GetTickCount();
  double elapsed = (double)(now - _start_dl_tick) * 0.001;
#else
  struct timeval now;
  gettimeofday(&now, NULL);
  double elapsed = (double)(now.tv_sec - _start_dl_timeval.tv_sec) +
    (double)(now.tv_usec - _start_dl_timeval.tv_usec) / 1000000.0;
#endif

  int ielapsed = (int)elapsed;
  _main_object->set_int_property("downloadElapsedSeconds", ielapsed);

  sprintf(buffer, "%d:%02d", ielapsed / 60, ielapsed % 60);
  _main_object->set_string_property("downloadElapsedFormatted", buffer);

  if (progress > 0 && (elapsed > 5.0 || progress > 0.2)) {
    double this_total = elapsed / progress;
    double this_remaining = max(this_total - elapsed, 0.0);

    // Age out any old time reports.
    double old = elapsed - min(time_average, this_remaining);
    while (!_time_reports.empty() && _time_reports.front()._report_time < old) {
      TimeReport &tr0 = _time_reports.front();
      _total_time_reports -= tr0._total;
      _time_reports.pop_front();
    }
    if (_time_reports.empty()) {
      _total_time_reports = 0.0;
    }

    // Add a new time report.
    TimeReport tr;
    tr._total = this_total;
    tr._report_time = elapsed;
    _time_reports.push_back(tr);
    _total_time_reports += tr._total;

    // Now get the average report.
    if (!_time_reports.empty()) {
      double total = _total_time_reports / (double)_time_reports.size();
      double remaining = max(total - elapsed, 0.0);
      int iremaining = (int)(remaining + 0.5);
      _main_object->set_int_property("downloadRemainingSeconds", iremaining);
      sprintf(buffer, "%d:%02d", iremaining / 60, iremaining % 60);
      _main_object->set_string_property("downloadRemainingFormatted", buffer);
    }
  }
}

/**
 * Notified when a required package is fully downloaded, or failed.
 */
void P3DInstance::
report_package_done(P3DPackage *package, bool success) {
  nout << "Done installing " << package->get_package_name()
       << ": success = " << success << "\n";

  if (package == _image_package) {
    // A special case: we just downloaded the image package, so get the image
    // files out of it and point them to the splash window.
    string package_dir = package->get_package_dir();
    const TiXmlElement *xconfig = package->get_xconfig();
    if (xconfig == NULL) {
      nout << "No <config> entry in image package\n";
      return;
    }
    package->mark_used();

    for (int i = 0; i < (int)IT_none; ++i) {
      if (_image_files[i]._use_standard_image) {
        // This image indexes into the package.  Go get the standard image
        // filename.
        string token = string(_image_type_names[i]) + "_img";
        const string *basename = xconfig->Attribute(token);
        if (basename == NULL) {
          nout << "No entry in image package for " << token << "\n";
        } else {
          string image_filename = package_dir + "/" + *basename;
          _image_files[i]._filename = image_filename;

          // If the image should be on the window now, and the window still
          // exists, put it up.
          if (_splash_window != NULL &&
              _image_files[i]._image_placement != P3DSplashWindow::IP_none) {
            P3DSplashWindow::ImagePlacement image_placement = _image_files[i]._image_placement;
            _splash_window->set_image_filename(image_filename, image_placement);
          }
        }
      }
    }
    return;
  }

  if (package == _certlist_package) {
    // Another special case: successfully downloading certlist (or failing to
    // download it) means we can finish checking the authenticity of the p3d
    // file.

    package->mark_used();

    // Take down the download progress.
    if (_splash_window != NULL) {
      _splash_window->set_install_progress(0.0, true, 0);
    }
    set_install_label("");

    P3DInstanceManager *inst_mgr = P3DInstanceManager::get_global_ptr();
    inst_mgr->read_certlist(package);
    check_p3d_signature();
    return;
  }

  if (package == _p3dcert_package) {
    // Another special case: successfully downloading p3dcert means we can
    // enable the auth button.

    package->mark_used();

    // Take down the download progress.
    if (_splash_window != NULL) {
      _splash_window->set_install_progress(0.0, true, 0);
    }
    set_install_label("");
    mark_p3d_untrusted();
    return;
  }

  if (success) {
    report_package_progress(package, 1.0);
    start_next_download();
  } else {
    send_notify("ondownloadfail");
    set_failed();
  }
}

/**
 * Sets the install label that will be displayed on the splash window, if it
 * is present.
 */
void P3DInstance::
set_install_label(const string &install_label) {
  _install_label = install_label;
  if (_splash_window != NULL) {
    _splash_window->set_install_label(_install_label);
  }
}

/**
 * Actually paints the rendered image to the browser window.  This is only
 * needed for OSX, where the child process isn't allowed to do it directly.
 */
void P3DInstance::
paint_window() {
#ifdef __APPLE__
  const P3D_window_handle &handle = _wparams.get_parent_window();
  if (handle._window_handle_type == P3D_WHT_osx_port) {
#if !__LP64__
    paint_window_osx_port();
#endif

  } else if (handle._window_handle_type == P3D_WHT_osx_cgcontext) {
    const P3D_window_handle &handle = _wparams.get_parent_window();
    assert(handle._window_handle_type == P3D_WHT_osx_cgcontext);
    CGContextRef context = handle._handle._osx_cgcontext._context;

    paint_window_osx_cgcontext(context);
  }
#endif  // __APPLE__
}

#if defined(__APPLE__) && !__LP64__
/**
 * Fills _reversed_buffer with the pixels from the current frame, suitable for
 * rendering via the old QuickDraw interface.  Returns true on success, or
 * false if there is no Panda3D window visible.  Only needed on OSX.
 */
bool P3DInstance::
get_framebuffer_osx_port() {
  if (_swbuffer == NULL || !_instance_window_attached) {
    // We don't have a Panda3D window yet.
    return false;
  }

  // blit rendered framebuffer into window backing store
  int x_size = min(_wparams.get_win_width(), _swbuffer->get_x_size());
  int y_size = min(_wparams.get_win_height(), _swbuffer->get_y_size());
  size_t rowsize = _swbuffer->get_row_size();

  if (_swbuffer->ready_for_read()) {
    // Copy the new framebuffer image from the child process.
    const void *framebuffer = _swbuffer->open_read_framebuffer();

    // We have to reverse the image vertically first (different conventions
    // between Panda and Mac).
    for (int yi = 0; yi < y_size; ++yi) {
#ifndef __BIG_ENDIAN__
      // On a little-endian machine, we only have to reverse the order of the
      // rows.
      memcpy(_reversed_buffer + (y_size - 1 - yi) * rowsize,
             (char *)framebuffer + yi * rowsize,
             rowsize);

#else  // __BIG_ENDIAN__
      // On a big-endian machine, we need to do more work.

      // It appears that kBGRAPixelFormat, below, is ignored on big-endian
      // machines, and it is treated as KARGBPixelFormat regardless of what we
      // specify.  Vexing.  To compensate for this, we have to reverse the
      // color channels ourselves on big-endian machines.

      const char *source = (const char *)framebuffer + yi * rowsize;
      const char *stop = source + x_size * 4;
      char *dest = (_reversed_buffer + (y_size - 1 - yi) * rowsize);
      while (source < stop) {
        char b = source[0];
        char g = source[1];
        char r = source[2];
        char a = source[3];
        dest[0] = a;
        dest[1] = r;
        dest[2] = g;
        dest[3] = b;
        dest += 4;
        source += 4;
      }
#endif
    }

    _swbuffer->close_read_framebuffer();

    if (_splash_window != NULL && _splash_window->get_visible()) {
      // If the splash window is up, time to hide it.  We've just rendered a
      // real frame.
      _splash_window->set_visible(false);
    }

  } else {
    // No frame ready.  Just re-paint the frame we had saved last time.
  }

  return true;
}
#endif  // __APPLE__

#ifdef __APPLE__
/**
 * Fills _reversed_buffer with the pixels from the current frame, suitable for
 * rendering via the new CoreGraphics interface.  Returns true on success, or
 * false if there is no Panda3D window visible.  Only needed on OSX.
 */
bool P3DInstance::
get_framebuffer_osx_cgcontext() {
  if (_swbuffer == NULL || !_instance_window_attached) {
    // We don't have a Panda3D window yet.
    return false;
  }

  // blit rendered framebuffer into window backing store
  int x_size = min(_wparams.get_win_width(), _swbuffer->get_x_size());
  int y_size = min(_wparams.get_win_height(), _swbuffer->get_y_size());
  size_t rowsize = _swbuffer->get_row_size();

  if (_swbuffer->ready_for_read()) {
    // Copy the new framebuffer image from the child process.
    const void *framebuffer = _swbuffer->open_read_framebuffer();
    memcpy(_reversed_buffer, framebuffer, y_size * rowsize);
    _swbuffer->close_read_framebuffer();

    if (_splash_window != NULL && _splash_window->get_visible()) {
      // If the splash window is up, time to hide it.  We've just rendered a
      // real frame.
      _splash_window->set_visible(false);
    }

  } else {
    // No frame ready.  Just re-paint the frame we had saved last time.
  }

  return true;
}
#endif  // __APPLE__

#if defined(__APPLE__) && !__LP64__
/**
 * Actually paints the rendered image to the browser window, using the OSX
 * deprecated QuickDraw interfaces.
 */
void P3DInstance::
paint_window_osx_port() {
  if (!get_framebuffer_osx_port()) {
    // No Panda3D window is showing.
    return;
  }

  int x_size = min(_wparams.get_win_width(), _swbuffer->get_x_size());
  int y_size = min(_wparams.get_win_height(), _swbuffer->get_y_size());
  size_t rowsize = _swbuffer->get_row_size();

  Rect src_rect = {0, 0, (short)y_size, (short)x_size};
  Rect ddrc_rect = {0, 0, (short)y_size, (short)x_size};

  QDErr err;

  GWorldPtr pGWorld;
  err = NewGWorldFromPtr(&pGWorld, k32BGRAPixelFormat, &src_rect, 0, 0, 0,
                         _reversed_buffer, rowsize);
  if (err != noErr) {
    nout << " error in NewGWorldFromPtr, called from paint_window()\n";
    return;
  }

  const P3D_window_handle &handle = _wparams.get_parent_window();
  assert(handle._window_handle_type == P3D_WHT_osx_port);
  GrafPtr out_port = handle._handle._osx_port._port;
  GrafPtr port_save = NULL;
  Boolean port_changed = QDSwapPort(out_port, &port_save);

  // Make sure the clipping rectangle isn't in the way.  Is there a better way
  // to eliminate the cliprect from consideration?
  Rect r = { 0, 0, 0x7fff, 0x7fff };
  ClipRect(&r);

  CopyBits(GetPortBitMapForCopyBits(pGWorld),
           GetPortBitMapForCopyBits(out_port),
           &src_rect, &ddrc_rect, srcCopy, 0);

  if (port_changed) {
    QDSwapPort(port_save, NULL);
  }

  DisposeGWorld(pGWorld);
}
#endif  // __APPLE__

#ifdef __APPLE__
/**
 * Actually paints the rendered image to the browser window.  This is the
 * newer CoreGraphics implementation on OSX.
 */
void P3DInstance::
paint_window_osx_cgcontext(CGContextRef context) {
  if (!get_framebuffer_osx_cgcontext()) {
    // No Panda3D window is showing.
    return;
  }

  int x_size = min(_wparams.get_win_width(), _swbuffer->get_x_size());
  int y_size = min(_wparams.get_win_height(), _swbuffer->get_y_size());

  if (_buffer_image != NULL) {
    CGRect region = { { 0, 0 }, { (CGFloat)x_size, (CGFloat)y_size } };
    CGContextDrawImage(context, region, _buffer_image);
  }
}
#endif  // __APPLE__

/**
 * Responds to the deprecated Carbon event types in Mac OSX.
 */
bool P3DInstance::
handle_event_osx_event_record(const P3D_event_data &event) {
  bool retval = false;

#if defined(__APPLE__) && !__LP64__
  assert(event._event_type == P3D_ET_osx_event_record);
  EventRecord *er = event._event._osx_event_record._event;

  Point pt = er->where;

  // Need to ensure we have the correct port set, in order to convert the
  // mouse coordinates successfully via GlobalToLocal().
  const P3D_window_handle &handle = _wparams.get_parent_window();
  if (handle._window_handle_type == P3D_WHT_osx_port) {
    GrafPtr out_port = handle._handle._osx_port._port;
    GrafPtr port_save = NULL;
    Boolean port_changed = QDSwapPort(out_port, &port_save);

    GlobalToLocal(&pt);

    if (port_changed) {
      QDSwapPort(port_save, NULL);
    }
  } else {
    // First, convert the coordinates from screen coordinates to browser
    // window coordinates.
    WindowRef window = handle._handle._osx_cgcontext._window;
    CGPoint cgpt = { (CGFloat)pt.h, (CGFloat)pt.v };
    HIPointConvert(&cgpt, kHICoordSpaceScreenPixel, NULL,
                   kHICoordSpaceWindow, window);

    // Then convert to plugin coordinates.
    pt.h = (short)(cgpt.x - _wparams.get_win_x());
    pt.v = (short)(cgpt.y - _wparams.get_win_y());
  }

  SubprocessWindowBuffer::Event swb_event;
  swb_event._source = SubprocessWindowBuffer::ES_none;
  swb_event._type = SubprocessWindowBuffer::ET_none;
  swb_event._code = 0;
  swb_event._flags = 0;
  add_carbon_modifier_flags(swb_event._flags, er->modifiers);

  bool trust_mouse_data = true;

  switch (er->what) {
  case mouseDown:
    swb_event._source = SubprocessWindowBuffer::ES_mouse;
    swb_event._type = SubprocessWindowBuffer::ET_button_down;
    retval = true;
    break;

  case mouseUp:
    swb_event._source = SubprocessWindowBuffer::ES_mouse;
    swb_event._type = SubprocessWindowBuffer::ET_button_up;
    retval = true;
    break;

  case keyDown:
  case keyUp:
  case autoKey:
    if (_swbuffer != NULL) {
      swb_event._source = SubprocessWindowBuffer::ES_keyboard;
      swb_event._code = er->message;
      if (er->what == keyUp) {
        swb_event._type = SubprocessWindowBuffer::ET_button_up;
      } else if (er->what == keyDown) {
        swb_event._type = SubprocessWindowBuffer::ET_button_down;
      } else {
        swb_event._type = SubprocessWindowBuffer::ET_button_again;
      }
      retval = true;
    }
    break;

  case updateEvt:
    paint_window();
    retval = true;
    break;

  case activateEvt:
    _mouse_active = ((er->modifiers & 1) != 0);
    break;

  case osEvt:
    // The mouse data sent with an "os event" seems to be in an indeterminate
    // space.
    trust_mouse_data = false;
    break;

  default:
    break;
  }

  if (_mouse_active) {
    swb_event._flags |= SubprocessWindowBuffer::EF_has_mouse;
    if (trust_mouse_data) {
      swb_event._x = pt.h;
      swb_event._y = pt.v;
      swb_event._flags |= SubprocessWindowBuffer::EF_mouse_position;
    }
  }

  if (_swbuffer != NULL) {
    _swbuffer->add_event(swb_event);
  }
#endif  // __APPLE__

  return retval;
}

/**
 * Responds to the new Cocoa event types in Mac OSX.
 */
bool P3DInstance::
handle_event_osx_cocoa(const P3D_event_data &event) {
  bool retval = false;

#ifdef __APPLE__
  assert(event._event_type == P3D_ET_osx_cocoa);
  const P3DCocoaEvent &ce = event._event._osx_cocoa._event;

  SubprocessWindowBuffer::Event swb_event;
  swb_event._source = SubprocessWindowBuffer::ES_none;
  swb_event._type = SubprocessWindowBuffer::ET_none;
  swb_event._code = 0;
  swb_event._flags = 0;

  switch (ce.type) {
  case P3DCocoaEventDrawRect:
    {
      CGContextRef context = ce.data.draw.context;
      paint_window_osx_cgcontext(context);
      retval = true;
    }
    break;

  case P3DCocoaEventMouseDown:
    swb_event._source = SubprocessWindowBuffer::ES_mouse;
    swb_event._type = SubprocessWindowBuffer::ET_button_down;
    retval = true;
    break;

  case P3DCocoaEventMouseUp:
    swb_event._source = SubprocessWindowBuffer::ES_mouse;
    swb_event._type = SubprocessWindowBuffer::ET_button_up;
    retval = true;
    break;

  case P3DCocoaEventKeyDown:
    swb_event._source = SubprocessWindowBuffer::ES_keyboard;
    swb_event._code = ce.data.key.keyCode << 8;
    if (ce.data.key.isARepeat) {
      swb_event._type = SubprocessWindowBuffer::ET_button_again;
    } else {
      swb_event._type = SubprocessWindowBuffer::ET_button_down;
      if (ce.data.key.characters[0] > 0 & ce.data.key.characters[0] < 0x100) {
        swb_event._code |= ce.data.key.characters[0];
      }
    }
    _modifiers = ce.data.key.modifierFlags;
    retval = true;
    break;

  case P3DCocoaEventKeyUp:
    swb_event._source = SubprocessWindowBuffer::ES_keyboard;
    swb_event._type = SubprocessWindowBuffer::ET_button_up;
    swb_event._code = ce.data.key.keyCode << 8;
    _modifiers = ce.data.key.modifierFlags;
    retval = true;
    break;

  case P3DCocoaEventFlagsChanged:
    _modifiers = ce.data.key.modifierFlags;
    retval = true;
    break;

  case P3DCocoaEventFocusChanged:
    _mouse_active = (ce.data.focus.hasFocus != 0);
    retval = true;
    break;
  }

  add_cocoa_modifier_flags(swb_event._flags, _modifiers);

  switch (ce.type) {
  case P3DCocoaEventMouseDown:
  case P3DCocoaEventMouseMoved:
  case P3DCocoaEventMouseDragged:
    swb_event._x = (int)ce.data.mouse.pluginX;
    swb_event._y = (int)ce.data.mouse.pluginY;
    swb_event._flags |= SubprocessWindowBuffer::EF_mouse_position;
  }

  if (_mouse_active) {
    swb_event._flags |= SubprocessWindowBuffer::EF_has_mouse;
  }

  if (_swbuffer != NULL) {
    _swbuffer->add_event(swb_event);
  }
#endif  // __APPLE__

  return retval;
}

/**
 * OSX only: adds the appropriate bits to the Event flag bitmask to correspond
 * to the modifier buttons held in the MacOS-style EventRecord::modifiers
 * mask.
 */
void P3DInstance::
add_carbon_modifier_flags(unsigned int &swb_flags, int modifiers) {
#if defined(__APPLE__) && !__LP64__
  if (modifiers & cmdKey) {
    swb_flags |= SubprocessWindowBuffer::EF_meta_held;
  }
  if (modifiers & shiftKey) {
    swb_flags |= SubprocessWindowBuffer::EF_shift_held;
  }
  if (modifiers & optionKey) {
    swb_flags |= SubprocessWindowBuffer::EF_alt_held;
  }
  if (modifiers & controlKey) {
    swb_flags |= SubprocessWindowBuffer::EF_control_held;
  }
#endif  // __APPLE__
}

/**
 * OSX only: adds the appropriate bits to the Event flag bitmask to correspond
 * to the modifier buttons held in the P3DCocoaEvent modifierFlags mask.
 */
void P3DInstance::
add_cocoa_modifier_flags(unsigned int &swb_flags, int modifiers) {
#ifdef __APPLE__
  if (modifiers & NSCommandKeyMask) {
    swb_flags |= SubprocessWindowBuffer::EF_meta_held;
  }
  if (modifiers & NSShiftKeyMask) {
    swb_flags |= SubprocessWindowBuffer::EF_shift_held;
  }
  if (modifiers & NSAlternateKeyMask) {
    swb_flags |= SubprocessWindowBuffer::EF_alt_held;
  }
  if (modifiers & NSControlKeyMask) {
    swb_flags |= SubprocessWindowBuffer::EF_control_held;
  }
#endif  // __APPLE__
}

/**
 * Generates a synthetic notify message here at the C++ level.
 *
 * Most notify messages are generated from within the Python code, and don't
 * use this method; but a few have to be sent before Python has started, and
 * those come through this method.
 */
void P3DInstance::
send_notify(const string &message) {
  nout << "send_notify(" << message << ")\n";
  P3D_request *request = new P3D_request;
  request->_instance = NULL;
  request->_request_type = P3D_RT_notify;
  request->_request._notify._message = strdup(message.c_str());
  add_baked_request(request);
}

#ifdef __APPLE__
/**
 * OSX only: allocates the _swbuffer and associated support objects.  If it
 * was already allocated, deallocates the previous one first.
 */
void P3DInstance::
alloc_swbuffer() {
  free_swbuffer();

  int x_size = _wparams.get_win_width();
  int y_size = _wparams.get_win_height();

  _swbuffer = SubprocessWindowBuffer::new_buffer
    (_shared_fd, _shared_mmap_size, _shared_filename, x_size, y_size);
  if (_swbuffer != NULL) {
    _reversed_buffer = new char[_swbuffer->get_framebuffer_size()];
    memset(_reversed_buffer, 0, _swbuffer->get_row_size());
    size_t rowsize = _swbuffer->get_row_size();

    _buffer_data = CFDataCreateWithBytesNoCopy(NULL, (const UInt8 *)_reversed_buffer,
                                               y_size * rowsize, kCFAllocatorNull);

    _data_provider = CGDataProviderCreateWithCFData(_buffer_data);
    _buffer_color_space = CGColorSpaceCreateDeviceRGB();

    _buffer_image = CGImageCreate(x_size, y_size, 8, 32, rowsize, _buffer_color_space,
                                  kCGImageAlphaNoneSkipFirst | kCGBitmapByteOrder32Little,
                                  _data_provider, NULL, false, kCGRenderingIntentDefault);

  }
}
#endif  // __APPLE__

#ifdef __APPLE__
/**
 * OSX only: releases the _swbuffer and associated support objects previously
 * allocated by alloc_swbuffer().
 */
void P3DInstance::
free_swbuffer() {
  if (_swbuffer != NULL) {
    SubprocessWindowBuffer::destroy_buffer(_shared_fd, _shared_mmap_size,
                                           _shared_filename, _swbuffer);
    _swbuffer = NULL;
  }
  if (_reversed_buffer != NULL) {
    delete[] _reversed_buffer;
    _reversed_buffer = NULL;
  }

  if (_buffer_image != NULL) {
    CGImageRelease(_buffer_image);
    CGColorSpaceRelease(_buffer_color_space);
    CGDataProviderRelease(_data_provider);
    CFRelease(_buffer_data);

    _buffer_data = NULL;
    _data_provider = NULL;
    _buffer_color_space = NULL;
    _buffer_image = NULL;
  }
}
#endif  // __APPLE__


#ifdef __APPLE__
/**
 * OSX only: this callback is associated with a CFRunLoopTimer, to be called
 * periodically for updating the frame.
 */
void P3DInstance::
timer_callback(CFRunLoopTimerRef timer, void *info) {
  P3DInstance *self = (P3DInstance *)info;
  self->request_refresh();
}
#endif  // __APPLE__

/**
 *
 */
P3DInstance::ImageDownload::
ImageDownload(P3DInstance *inst, int index) :
  _inst(inst),
  _index(index)
{
}

/**
 * Intended to be overloaded to generate a callback when the download
 * finishes, either successfully or otherwise.  The bool parameter is true if
 * the download was successful.
 */
void P3DInstance::ImageDownload::
download_finished(bool success) {
  P3DFileDownload::download_finished(success);
  if (success) {
    // We've successfully downloaded the image (directly, not via the package
    // interface).
    _inst->_image_files[_index]._filename = get_filename();

    // Put it onscreen if it's supposed to be onscreen now, and our splash
    // window still exists.
    if (_inst->_splash_window != NULL &&
        _inst->_image_files[_index]._image_placement != P3DSplashWindow::IP_none) {
      P3DSplashWindow::ImagePlacement image_placement = _inst->_image_files[_index]._image_placement;
      _inst->_splash_window->set_image_filename(get_filename(), image_placement);
    }
  }
}

/**
 *
 */
P3DInstance::InstanceDownload::
InstanceDownload(P3DInstance *inst) :
  _inst(inst)
{
}

/**
 * Intended to be overloaded to generate an occasional callback as new data
 * comes in.
 */
void P3DInstance::InstanceDownload::
download_progress() {
  P3DFileDownload::download_progress();
  _inst->report_instance_progress(get_download_progress(), is_download_progress_known(), get_total_data());
}

/**
 * Intended to be overloaded to generate a callback when the download
 * finishes, either successfully or otherwise.  The bool parameter is true if
 * the download was successful.
 */
void P3DInstance::InstanceDownload::
download_finished(bool success) {
  P3DFileDownload::download_finished(success);
  if (success) {
    // We've successfully downloaded the instance data.
    _inst->report_instance_progress(1.0, true, 0);
    _inst->priv_set_p3d_filename(get_filename());
  } else {
    // Oops, no joy on the instance data.
    _inst->send_notify("ondownloadfail");
    _inst->set_failed();
  }
}