var data;
var arr = [];
var nrows;
var max, min, nvals;
var h = 1200, w = 1200; // dimensions
var margin = 50; // margin
var interval;


function preload() {
	data = loadTable('0.edges');
}

function sortNumber(a,b) { // function to help numerical order sorting
    return a - b;
}

function setup() {

	nrows = data.getRowCount(); // num rows in data

	for (var i=0; i<nrows; i++) { // get unique values and append to arr
		var s = split(data.getString(i,0), " ");
		if (! arr.includes(s[0])) {
			append(arr, s[0]);
		}
		if (! arr.includes(s[1])) {
			append(arr, s[1]);
		}
	}

	max = max(arr); // max value
	min = min(arr); // min value
	nvals = arr.length; // num unique values
	arr.sort(sortNumber); // sort values in arr
	// print(arr);

	interval = (h-margin)/nvals;
	// print(interval);
}


function draw() {

	clear();
	createCanvas(1300, 1300);

	// draw grid
	for (var i=0; i<nvals; i++) {
		strokeWeight(0.3);
		stroke(200);
		line(margin, margin+(interval*i), w, margin+(interval*i));
		line(margin+(interval*i), margin, margin+(interval*i), h);
	}

	// populate matrix
	for (var i=0; i<nrows; i++) {
		var s = split(data.getString(i,0), " ");
		var src = s[0];
		var tar = s[1];
		var indexsrc = arr.indexOf(s[0]);
		var indextar = arr.indexOf(s[1]);

		// draw rect at coordinates
		fill(250,128,114);
		strokeWeight(0.2);
		rect(margin+(indextar*interval),margin+(indexsrc*interval), interval, interval);
	}

	// axis labels
	for (var i=0; i<nvals; i++) {
		if (interval < 10) { // measure if each axis too small
			if (i%5 == 0) {
				textSize(10);
				fill(50);
				textAlign(RIGHT);
				text(arr[i],margin-10,margin+(interval*0.7)+(i*interval));

				push(); // x axis labels
				rotate((3/4)*(2*PI)); // rotate anticlockwise 90 deg
				textAlign(LEFT);
				textSize(10);
				fill(50);
				text(arr[i],-margin+10,margin+(interval*0.7)+(i*interval));
				pop();
			}
		}
		else {
			textSize(10);
			fill(50);
			textAlign(RIGHT);
			text(arr[i],margin-10,margin+(interval*0.7)+(i*interval));

			push(); // x axis labels
			rotate((3/4)*(2*PI)); // rotate anticlockwise 90 deg
			textAlign(LEFT);
			textSize(10);
			fill(50);
			text(arr[i],-margin+10,margin+(interval*0.7)+(i*interval));
			pop();
		}
	}

	// mouseover function outside population function so that text is overlayed
	for (var i=0; i<nrows; i++) {
		var s = split(data.getString(i,0), " ");
		var src = s[0];
		var tar = s[1];
		var indexsrc = arr.indexOf(s[0]);
		var indextar = arr.indexOf(s[1]);

		if ((mouseX>(margin+(indextar*interval)-1)) && (mouseX<(margin+(indextar*interval)+interval+1)) && 
			(mouseY>(margin+(indexsrc*interval)-1)) && (mouseY<(margin+(indexsrc*interval)+interval+1))) {
			fill(254,223,0);
			stroke(1);
			strokeWeight(0.5);
			rect(margin+(indextar*interval)-2,margin+(indexsrc*interval)-2, interval+4, interval+4);
			textSize(15);
			fill(50);
			textAlign(CENTER);
			text("(" + src + ", " + tar+")", margin+(indextar*interval) + (interval/2), margin+(indexsrc*interval)+40);
		}
	}

	// draw boundary
	strokeWeight(1);
	stroke(1);
	line(margin, margin, margin, h);
	line(margin, margin, w, margin);
	line(margin, h, w, h);
	line(w, margin, w, h);

	// noLoop();

}