var data;
var arr = []; // array for unique values
var nrows;
var nvals;
var h = 650, w = 650; // dimensions
var margin = 50;
var initPosArr = []; // an array of objects containing source and initial positions
var dispArr = []; // array of objects containing two vertices and displacement
var edispArr = [];
var finDispArr = []; // final displacement array
var posArr = []; // final position array

function preload() {
	data = loadTable('698.edges');
}

function initPos(src, x, y) {
	this.src = src;
	this.x = x; // random initial x val
	this.y = y; // random initial y val
}

function Vertex(v1, dispx, dispy) { // displacement between any two vertices where v1!=v2
	this.v1 = v1; 
	this.dispx = dispx; // displacement initially set to 0
	this.dispy = dispy;
}

function Edge(v1, edispx, edispy) { // displacement between any two edges where v1!=v2
	this.v1 = v1; 
	this.edispx = edispx; // displacement initially set to 0
	this.edispy = edispy;
}

function Disp(v, dx, dy) {
	this.v = v;
	this.dx = dx;
	this.dy = dy;
}

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

function getA(x, k) {
	return (sq(x)/k);
}

function getR(x, k) {
	return (sq(k)/x);
}

function setup() {

	nrows = data.getRowCount();
	for (var i=0; i<nrows; i++) { // create array of unique values --> 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]);
		}
	}

	nvals = arr.length; // number unique values
	arr.sort(sortNumber); // sort values in arr
	// print(arr);

	var A = h*w; // area
	var k = sqrt((A)/nvals); // k

	// Assign random positions
	for (var i=0; i<nvals; i++) {
		var src = arr[i]; // each vertex has a single initial point
		var x = random(h); // adjusted for drawing space
		var y = random(w); 
		var pos = new initPos(src, x, y);
		initPosArr[i] = pos;
	}

	// RUN ALGO
	for (var i=0; i<15; i++) { 
		
		// calculate repulsive forces
		for (var v=0; v<nvals; v++) { // for each vertex v
			var vdispx = 0;
			var vdispy = 0;
			for (var u=0; u<nvals; u++) { // for each vertex u not equal to v
				if (u!=v) { // if u != v
					var objV = initPosArr[v]; // return object initial positions
					var objU = initPosArr[u];
					var deltax = objV.x-objU.x;
					var deltay = objV.y-objU.y;
					vdispx = vdispx + (deltax/abs(deltax))*(getR(abs(deltax), k));
					// print(getR(abs(deltax), k));
					vdispy = vdispy + (deltay/abs(deltay))*(getR(abs(deltay), k));
					if ((u==nvals-1) || (v==nvals-1 && u==nvals-2)) {
						var dispObj = new Vertex(objV.src, vdispx, vdispy);
						append(dispArr, dispObj);
					}
				}
			}
		}

		// populate edisp arr
		for (var m=0; m<nvals; m++) { 
			var edispObj = new Edge(arr[m], 0, 0);
			append(edispArr, edispObj);
		}

		// calculate attractive forces
		for (var e=0; e<nrows; e++) {
			var s = split(data.getString(e,0), " ");
			objV = initPosArr[arr.indexOf(s[0])]; // return object initial positions
			objU = initPosArr[arr.indexOf(s[1])];
			deltax = objV.x-objU.x;
			deltay = objV.y-objU.y;
			// print("distance:", deltax, deltay)

			objV = edispArr[arr.indexOf(s[0])]; // write objects as edisp positions
			objU = edispArr[arr.indexOf(s[1])];

			// calculate displacements of x and y for V and U
			// modify edispArr values
			var evdispx = objV.edispx-(deltax/abs(deltax))*(getA(abs(deltax),k)); 
			var evdispy = objV.edispy-(deltay/abs(deltay))*(getA(abs(deltay),k));
			edispArr[arr.indexOf(s[0])].edispx = evdispx;
			edispArr[arr.indexOf(s[0])].edispy = evdispy;

			var eudispx = objU.edispx+(deltax/abs(deltax))*(getA(abs(deltax),k));
			var eudispy = objU.edispy+(deltay/abs(deltay))*(getA(abs(deltay),k));
			edispArr[arr.indexOf(s[1])].edispx = eudispx;
			edispArr[arr.indexOf(s[1])].edispy = eudispy;
		}

		// Get final displacements
		for (var v=0; v<nvals; v++) {
			var dx = dispArr[v].dispx + edispArr[v].edispx;
			var dy = dispArr[v].dispy + edispArr[v].edispy;
			var finObj = new Disp(arr[v], dx, dy);
			append(finDispArr, finObj);
		}

		// limit displacement 
		for (var v=0; v<nvals; v++) {
			var t = (h+margin)/2;
			var obj = finDispArr[v];

			var posx = initPosArr[v].x + obj.dx;
			var posy = initPosArr[v].y + obj.dy;
			// print(posx, posy);

			var finPos = new initPos(arr[v], posx, posy);
			initPosArr[v] = finPos;
		}

		// print(initPosArr);

		// scale everything
		var maxVal = 0;
		for (var temp=0; temp<nvals; temp++) {
			var obj = initPosArr[temp];
			if (max(abs(obj.x), abs(obj.y)) > maxVal) {
				maxVal = max(abs(obj.x), abs(obj.y));
			}
		}

		for (var temp=0; temp<nvals; temp++) {
			var obj = initPosArr[temp];
			if ((obj.x < 0.8*maxVal) && (obj.x > (-maxVal)*0.8)) {
				var tempx = map(obj.x, -maxVal*0.8, maxVal*0.8, margin, w);
			}
			else {
				var tempx = map(obj.x, -maxVal, maxVal, margin, w)*0.8;
			}
			if ((obj.y < 0.8*maxVal) && (obj.y > (-maxVal)*0.8)) {
				var tempy = map(obj.y, -maxVal*0.8, maxVal*0.8, margin, h);
			}
			else {
				var tempy = map(obj.y, -maxVal, maxVal, margin, h)*0.8;
			}
			initPosArr[temp].x = tempx;
			initPosArr[temp].y = tempy;
		}
	}

	// print(initPosArr);


}

function draw() {

	clear();
	createCanvas(800,800); // drawing canvas

	for (var i=0; i<nrows; i++) { 
		var s = split(data.getString(i,0), " ");
		var p1 = s[0];
		var p2 = s[1];
		var obj1 = initPosArr[arr.indexOf(p1)];
		var obj2 = initPosArr[arr.indexOf(p2)];
		stroke(102,118,134);
		strokeWeight(0.3);
		line(obj1.x, obj1.y, obj2.x, obj2.y);

		if (dist(mouseX, mouseY, obj1.x, obj1.y) < 8) {
			stroke(80);
			strokeWeight(2);
			line(obj1.x, obj1.y, obj2.x, obj2.y);
			fill(250,160,114);
			ellipse(obj2.x, obj2.y, 10, 10);
		}
	}

	for (var i=0; i<initPosArr.length; i++) {
		var obj = initPosArr[i];
		fill(0,191,255);
		stroke(50);
		strokeWeight(0.5);
		ellipse(obj.x, obj.y, 8, 8);

		if (dist(mouseX, mouseY, obj.x, obj.y) < 8) {
			fill(250,160,114);
			strokeWeight(1);
			ellipse(obj.x, obj.y, 10, 10);
			textSize(13);
			fill(50);
			text(obj.src, obj.x+12, obj.y-12)
		}
	}


}