var canvas_matrix;
var canvas;
var table_edges;
var rangeW,rangeH;
var k;
var temperature;
var circle;
var graph;
var Graph = function() {
      this.nodes = {};
      this.pos_old ={};
      this.pos = {};
      this.disp = {};
};

function preload(){
    table_edges = loadTable('414.edges', 'tsv');
    
}

function setup() {
    graph = new Graph();
    for(var i=0;i<table_edges.getRowCount();i++){
        var arr = table_edges.getString(i,0).split(' ');
        if(!graph.contains(arr[0])){
            graph.addNode(arr[0]);
        }
        else if(!graph.contains(arr[1])){
            graph.addNode(arr[1]);
        }
    }
     canvas_matrix = {
        width: 800,
        height: 800,
        position: 25
    };
    canvas  = {
        width:canvas_matrix.width*2,
        height: canvas_matrix.height*2
    };
    circle = {
        r: canvas_matrix.width/canvas_matrix.width*10
    };
    
    createCanvas(canvas.width, canvas.height);
    k = Math.sqrt((canvas_matrix.width)*(canvas_matrix.height)/graph.getNodesLength());
    temperature = canvas_matrix.width/100; //698:100 //3890:1070 
    cooldown = temperature/20; //698:10 //3890:70
    assignPositions();
}

////////function Graph////////////////////////////////////
Graph.prototype.addNode = function(node) {
      this.nodes[node] = node;
};
Graph.prototype.addPos = function(node,x, y) {
     this.pos[node] = [x, y];
};
Graph.prototype.addPosOld = function(node,x, y) {
     this.pos_old[node] = [x, y];
};
Graph.prototype.addDisp = function(node,x,y) {
     this.disp[node] = [x,y];
};
Graph.prototype.contains = function(node) {
      return this.nodes[node] ? true : false;
};
Graph.prototype.getNodesLength = function() {
      var count = 0;
      for (var node in this.nodes) {
            count++;
      }
        return count;
};
function getRandomInt(min, max) {
  return Math.floor(Math.random() * (max - min)) + min;
}
function fa(x){
    return (x*x)/k;
}

function fr(x){
    return (k*k/x); 
}

function magnitude(node1,node2){
    var dx = graph.pos[node2][0] - graph.pos[node1][0];
    var dy = graph.pos[node2][1] - graph.pos[node1][1];
    var distance = Math.sqrt(dx*dx + dy*dy);
    return distance;
}

function assignPositions(){
    for(var v in graph.nodes){
         graph.addPos(v,getRandomInt(canvas_matrix.position,canvas_matrix.width),getRandomInt(canvas_matrix.position,canvas_matrix.height));
         graph.addPosOld(v,getRandomInt(canvas_matrix.position,canvas_matrix.width),getRandomInt(canvas_matrix.position,canvas_matrix.height));
    }
}

function findMin(val1,val2){
    if(val1 < val2){
        return val1;
    }
    return val2;
}
function findMax(val1,val2){
    if(val1 > val2){
        return val1;
    }
    return val2;
}

function draw(){
    background(255);
    push();
     textStyle(BOLD);
     textSize(24);
     text("The Force-Directed Layout",canvas_matrix.position,canvas_matrix.position);
     pop()
    
     for (var v in graph.nodes){
            graph.addDisp(v,0,0);
        for(var u in graph.nodes){
            if(u!=v){
                var delta = magnitude(v,u);
                if(delta <= 0){
                    delta = 0.00001;
                }
                var dx = graph.pos[v][0] - graph.pos[u][0];
                var dy = graph.pos[v][1] - graph.pos[u][1];
                graph.disp[v][0] += (dx/delta) * (fr(delta));
                graph.disp[v][1] += (dy/delta) * (fr(delta));
           }     
        }
    }
    
    for(var i=0;i< table_edges.getRowCount();i++){
        var arr = table_edges.getString(i,0).split(' ');
        var v= arr[0];
        var u = arr[1];
        var delta = magnitude(v,u);
        if(delta<=0){
            delta = 0.00001;
        }
        var dx = graph.pos[v][0] - graph.pos[u][0];
        var dy = graph.pos[v][1] - graph.pos[u][1];
        graph.disp[v][0] -= (dx/delta)*(fa(delta));
        graph.disp[v][1] -= (dy/delta)*(fa(delta));
        graph.disp[u][0] += (dx/delta)*(fa(delta));
        graph.disp[u][1] += (dy/delta)*(fa(delta));
        push();
        strokeWeight(0.3);
        line(graph.pos[v][0]+canvas_matrix.position,graph.pos[v][1]+canvas_matrix.position,graph.pos[u][0]+canvas_matrix.position,graph.pos[u][1]+canvas_matrix.position);
        pop();
        push();
        noStroke();
        fill('rgb(191, 63, 138)');
        ellipse(graph.pos[v][0]+canvas_matrix.position,graph.pos[v][1]+canvas_matrix.position, circle.r,circle.r);
        pop();
        var d = dist(mouseX,mouseY,graph.pos[v][0]+canvas_matrix.position,graph.pos[v][1]+canvas_matrix.position);
        if(d <= circle.r){
            push();
            textSize(16);
            stroke(255);
            textStyle(BOLD);
            text(arr[0],graph.pos[v][0]+canvas_matrix.position+10,graph.pos[v][1]+canvas_matrix.position+10);
            text(arr[1],graph.pos[u][0]+canvas_matrix.position+10,graph.pos[u][1]+canvas_matrix.position+10);
            pop();
            push();
            strokeWeight(1);
            stroke(0)
            line(graph.pos[v][0]+canvas_matrix.position,graph.pos[v][1]+canvas_matrix.position,graph.pos[u][0]+canvas_matrix.position,graph.pos[u][1]+canvas_matrix.position);
            pop(); 
        } 
    }
    for(var v in graph.nodes){
             var dx = graph.pos[v][0];
             var dy = graph.pos[v][1];
             var magnitude_disp = Math.sqrt(dx*dx + dy*dy)*10;
            if(magnitude_disp <= 0){
                magnitude_disp = 0.00001;
            }
            graph.pos[v][0] += (graph.disp[v][0]/magnitude_disp) * findMin(magnitude_disp,temperature);
            graph.pos[v][1] += (graph.disp[v][1]/magnitude_disp) * findMin(magnitude_disp,temperature);
        
            graph.pos[v][0] = findMin(graph.pos_old[v][0], findMax(50, graph.pos[v][0]));
            graph.pos[v][1] = findMin(graph.pos_old[v][1], findMax(50, graph.pos[v][1]));
    } 
        temperature -= cooldown;
        if (temperature < cooldown){
            temperature = 0;
        }
        print(cooldown);
        print(temperature);
}