/*
Copyright © 2021 Zoraiz Hassan <hzoraiz8@gmail.com>

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

package image_conversions

// Reference taken from http://paulbourke.net/dataformats/asciiart/
var asciiTableSimple = map[int]string{
	0: " ",
	1: ".",
	2: ":",
	3: "-",
	4: "=",
	5: "+",
	6: "*",
	7: "#",
	8: "%",
	9: "@",
}

// Reference taken from http://paulbourke.net/dataformats/asciiart/
var asciiTableDetailed = map[int]string{
	0:  " ",
	1:  ".",
	2:  "'",
	3:  "`",
	4:  "^",
	5:  "\"",
	6:  ",",
	7:  ":",
	8:  ";",
	9:  "I",
	10: "l",
	11: "!",
	12: "i",
	13: ">",
	14: "<",
	15: "~",
	16: "+",
	17: "_",
	18: "-",
	19: "?",
	20: "]",
	21: "[",
	22: "}",
	23: "{",
	24: "1",
	25: ")",
	26: "(",
	27: "|",
	28: "/",
	29: "t",
	30: "f",
	31: "j",
	32: "r",
	33: "x",
	34: "n",
	35: "u",
	36: "v",
	37: "c",
	38: "z",
	39: "X",
	40: "Y",
	41: "U",
	42: "J",
	43: "C",
	44: "L",
	45: "Q",
	46: "0",
	47: "O",
	48: "Z",
	49: "m",
	50: "w",
	51: "q",
	52: "p",
	53: "d",
	54: "b",
	55: "k",
	56: "h",
	57: "a",
	58: "o",
	59: "*",
	60: "#",
	61: "M",
	62: "W",
	63: "&",
	64: "8",
	65: "%",
	66: "B",
	67: "@",
	68: "$",
}

// For each individual element of imgSet in ConvertToASCIISlice()
const MAX_VAL float32 = 65535

// Converts the 2D uint32 slice of image data (each element being each pixel of shrinked image)
// to a 2D string slice with each pixel value being compared to a map of hardcoded ascii characters.
//
// This function contains 69 characters
func ConvertToAsciiDetailed(imgSet [][]uint32) [][]string {

	height := len(imgSet)
	width := len(imgSet[0])

	result := make([][]string, height)
	for i := range result {
		result[i] = make([]string, width)
	}

	for i := 0; i < height; i++ {
		var tempSlice []string
		for j := 0; j < width; j++ {

			value := float32(imgSet[i][j])

			tempFloat := (value / MAX_VAL) * float32(len(asciiTableDetailed))
			if value == MAX_VAL {
				tempFloat = float32(len(asciiTableDetailed) - 1)
			}
			tempInt := int(tempFloat)

			tempSlice = append(tempSlice, asciiTableDetailed[tempInt])
		}
		result[i] = tempSlice
	}

	return result
}

// Converts the 2D uint32 slice of image data (each element being each pixel of shrinked image)
// to a 2D string slice with each pixel value being compared to a map of hardcoded ascii characters.
//
// This function contains 10 characters
func ConvertToAsciiSimple(imgSet [][]uint32) [][]string {

	height := len(imgSet)
	width := len(imgSet[0])

	result := make([][]string, height)
	for i := range result {
		result[i] = make([]string, width)
	}

	for i := 0; i < height; i++ {
		var tempSlice []string
		for j := 0; j < width; j++ {

			value := float32(imgSet[i][j])
			tempFloat := (value / MAX_VAL) * float32(len(asciiTableSimple))
			if value == MAX_VAL {
				tempFloat = float32(len(asciiTableSimple) - 1)
			}
			tempInt := int(tempFloat)

			tempSlice = append(tempSlice, asciiTableSimple[tempInt])
		}
		result[i] = tempSlice
	}

	return result
}