#include <opencv2/core/core.hpp> 
#include <opencv2/highgui/highgui.hpp>
#include <opencv2/imgproc/imgproc.hpp>
#include <opencv2/opencv.hpp>
#include <iostream>

using namespace cv;

// input files
char* inputBoardBMP = "chessboard.bmp";

char* inputBoardJPG = "chessboard.jpg";

char* inputBoardPNG = "chessboard.png";

char* inputBoardTIF = "chessboard.tif";

// Mats
Mat originalImg, greyImg, threshImg;
Mat blackSquares, whiteSquares;
Mat finishedImg;

// Thresholds

/**
 * range: 0-255
 */
int thresholdValue = 0;

/**
 * 0: binary
 * 1: binary-inverted
 * 2: truncate
 * 3: to-zero
 * 4: to-zero-inverted
 */ 
int thresholdType = 0;

int const MAX_TYPE = 4;
int const MAX_BINARY = 255;


// Window Names
char* colorWindow = "Color Image";
char* greyWindow = "Grey Image";
char* threshWindow = "Threshold Image";
char* whiteSquareWindow = "White Squares";
char* blackSquareWindow = "Black Squares";

// Function Prototypes
void Threshold_Demo(int, void*);
void Colorize_Demo(int, void*);

int main() {
	/**
	 * Type: 
	 * CV_LOAD_IMAGE_UNCHANGED: include transparency (alpha) channel
	 * CV_LOAD_IMAGE_GRAYSCALE: load as single-channel
	 * CV_LOAD_IMAGE_COLOR: load as BGR
	 */
	originalImg = imread(inputBoardJPG, IMREAD_COLOR);
	
	// ensure image was valid
	if(!originalImg.data) {
		std::cout << "Missing data." << std::endl;
		return -1;
	}
	
	// display the image
	namedWindow(colorWindow, WINDOW_AUTOSIZE);
	imshow(colorWindow, originalImg);
	
	// wait for user to press any key
	waitKey(0);
	
	// greyscale the image
	cvtColor(originalImg, greyImg, COLOR_BGR2GRAY);
	
	// display the grey image
	namedWindow(greyWindow, WINDOW_AUTOSIZE);
	imshow(greyWindow, greyImg);
	
	// wait for user to press any key
	waitKey(0);
	
	// close the windows
	//cvDestroyWindow(colorWindow);
	destroyWindow(greyWindow);
	
	namedWindow(threshWindow, WINDOW_NORMAL);
	
	// create type trackbar
	createTrackbar("Type ", threshWindow, &thresholdType, 
					MAX_TYPE, Threshold_Demo);
					
	// create value trackbar
	createTrackbar("Value ", threshWindow, &thresholdValue,
					MAX_BINARY, Threshold_Demo);
					
	Threshold_Demo(0, 0);
	
	waitKey(0);
	
	destroyWindow(threshWindow);

	if(thresholdType == 1) {
		blackSquares = threshImg.clone();
		bitwise_not(blackSquares, whiteSquares);
	}
	else if(thresholdType == 0) {
		whiteSquares = threshImg.clone();
		bitwise_not(whiteSquares, blackSquares);
	}
	else {
		destroyWindow(colorWindow);
		return 0;
	}
	
	
	namedWindow(whiteSquareWindow, WINDOW_AUTOSIZE);
	imshow(whiteSquareWindow, blackSquares);
	waitKey(0);
	
	destroyWindow(whiteSquareWindow);
	
	namedWindow(blackSquareWindow, WINDOW_AUTOSIZE);
	imshow(blackSquareWindow, whiteSquares);
	waitKey(0);
	
	destroyWindow(blackSquareWindow);
	destroyWindow(colorWindow);
	return 1;
}

void Threshold_Demo(int, void*) {

  // (src, dst, threshold value, max, type of threshold)
  threshold(greyImg, threshImg, thresholdValue, 
            MAX_BINARY, thresholdType);

  imshow(threshWindow, threshImg);
}