var canvas, ctx
var selectedItem
var mouseisdown
var chip = new Component("main");
var pinImages = [];
var wireVisuals = [];
var wireBeingDrawn = [];
images = {};
var x;
document.addEventListener("DOMContentLoaded", function(event){
  canvas = document.getElementById('logicsim');
  canvas.addEventListener("mousedown",selectItem);
  canvas.addEventListener("mouseup", function(){mouseisdown=false});
  canvas.addEventListener("mousemove",mousemove);
  document.addEventListener("keydown",checkKey);
  ctx = canvas.getContext('2d');
  preloadAssets();
  requestAnimationFrame(drawCanvas);
  x=setInterval(function(){chip.process()},1);
});
function getMousePos(c,e){
  var rect = c.getBoundingClientRect();
  return {
    x: e.clientX - rect.left,
    y: e.clientY - rect.top
  }
}
function checkKey(e){
  e=e||window.event;
  if(e.keyCode==27){
    selectedPin={component:-1,pin:-1};
    wireBeingDrawn=[];
  }
}
function isInside(c,point){
  return ( point.x > c.position.x && point.x < c.position.x + images[c.type].width) &&
     ( point.y > c.position.y && point.y < c.position.y + images[c.type].height);
}
function isInsidePin(p,point){
  return Math.sqrt(Math.pow((p.position.x-point.x),2)+Math.pow((p.position.y-point.y),2)) < p.radius;
}
var clickpos;
var nWireAttempts=0;
var selectedPin = {component:-1,pin:-1};
var hoveredPin = {component:-1,pin:-1,type:-1};
function selectItem(e){
  pos = getMousePos(canvas, e)
  if(hoveredPin.component>=0){
    if(hoveredPin.type==1){
      chip.pins[hoveredPin.pin]=1-chip.pins[hoveredPin.pin];
    } else {
      if(wireBeingDrawn.length>0){
        if(chip.connect(selectedPin, hoveredPin, nWireAttempts)){
          wireBeingDrawn[wireBeingDrawn.length-1]={component:hoveredPin.component,pin:hoveredPin.pin};
          wireVisuals.push({wireId:nWireAttempts,path:wireBeingDrawn.slice()});
          wireBeingDrawn=[];
          selectedPin={component:-1,pin:-1};
          nWireAttempts+=1;
        } else {
          console.log("noooo");
        }
      } else {
        wireBeingDrawn.push({component:hoveredPin.component,pin:hoveredPin.pin});
        wireBeingDrawn.push({x:pos.x,y:pos.y});
        selectedPin = {component:hoveredPin.component,pin:hoveredPin.pin};
      }
    }
  } else {
    if(wireBeingDrawn.length>0){
      wireBeingDrawn[wireBeingDrawn.length-1]={x:pos.x,y:pos.y};
      wireBeingDrawn.push({x:pos.x,y:pos.y})//slice());
    }
  }
  chip.zIndex.forEach(function(c,i){
    if (isInside(c, pos) && ctx.getImageData(pos.x,pos.y,1,1).data[3]) {
      mouseisdown = true;
      clickpos = pos;
			chip.sendToFront(chip.getProperIndex(c));
      // DELETE THIS LATER //
      return;
    }

  });
}
var pos;
function mousemove(e){
  pos = getMousePos(canvas,e);
  if(wireBeingDrawn.length>0){
    wireBeingDrawn[wireBeingDrawn.length-1]={x:pos.x,y:pos.y};
  }
  if(mouseisdown){
		last = chip.zIndex.length-1;
    chip.zIndex[last].position.x -= (clickpos.x - pos.x);
   	chip.zIndex[last].position.y -= (clickpos.y - pos.y);
    clickpos = pos;
  }
  if(!pinImages.some(pi=>{
    if(isInsidePin(pi,pos)){
      hoveredPin = {component:pi.component,pin:pi.pin,type:pi.type}
      return true;
    }
  })){
    hoveredPin={component:-1,pin:-1};
  }
}
function preloadAssets(){
	Object.entries(chips).forEach(function(c){
		if (!(c[1].image in images)){
    	images[c[0]] = new Image();
    	images[c[0]].src = c[1].image;
		}
  });
}
function makeArr(startValue, stopValue, cardinality) {
  var arr = [];
  var step = (stopValue - startValue) / (cardinality - 1);
  for (var i = 0; i < cardinality; i++) {
    arr.push(startValue + (step * i));
  }
  return arr;
}
function drawCircle(x,y,radius,colour){
  ctx.beginPath();
  ctx.arc(Math.floor(x),Math.floor(y),radius,0,2*Math.PI,false);
  ctx.fillStyle=colour;
  ctx.fill();
}
function drawLine(origin,destination,width,colour){
  ctx.beginPath();
  ctx.moveTo(origin.x,origin.y);
  ctx.lineTo(destination.x,destination.y);
  ctx.strokeStyle=colour;
  ctx.lineWidth=width;
  ctx.stroke();
}
function drawCanvas() {
  pI = [];
  ctx.clearRect(0, 0, canvas.width, canvas.height);
  ctx.canvas.width  = 600;
  ctx.canvas.height = 600;
  ctx.fillStyle="lightgray";
  ctx.fillRect(0,0,20,canvas.height);
  //components.slice().reverse().forEach(function(c){
  for(var i=0;i<wireBeingDrawn.length-1;i++){
    if(i==0)
      p1=pinImages.find(p=>p.component==wireBeingDrawn[0].component && p.pin==wireBeingDrawn[0].pin && p.type==0).position;
    else
      p1=wireBeingDrawn[i];
    //if(i==wireBeingDrawn.length-2)
    //  p2=pinImages.find(p=>p.component==wireBeingDrawn[i+1].component&&p.pin==wireBeingDrawn[i+1].pin&&p.type==0).position;
    //else
      p2=wireBeingDrawn[i+1]
    drawLine(p1,p2,3,["black","red"][chip.subComponents[wireBeingDrawn[0].component].pins[wireBeingDrawn[0].pin]]);
  }
  wireVisuals=wireVisuals.filter(wv=> {return chip.wires.findIndex(w=>w.wireId==wv.wireId)>=0});
  wireVisuals.forEach(wv=>{
    for(var i=0;i<wv.path.length-1;i++){
      if(i==0)
        p1=pinImages.find(p=>p.component==wv.path[0].component && p.pin==wv.path[0].pin && p.type==0).position;
      else
        p1=wv.path[i];
      if(i==wv.path.length-2)
        p2=pinImages.find(p=>p.component==wv.path[i+1].component&&p.pin==wv.path[i+1].pin&&p.type==0).position;
      else
        p2=wv.path[i+1];
      drawLine(p1,p2,3,["black","red"][chip.subComponents[wv.path[0].component].pins[wv.path[0].pin]]);
    }
  });
  chip.pins.forEach((p,i)=>{
    if(i<chip.inputs){
      centerX=10;
      otherpins = chip.inputs;
      pindex=i;
    } else {
      centerX = canvas.width - 10;
      otherpins = chip.pins.length - chip.inputs;
      pindex = i - chip.inputs;
    }
    ys = makeArr(0-(20/otherpins),0+canvas.height+(20/otherpins),otherpins+2);
    ys.shift();
    ys.pop();
    centerY = ys[pindex];
    pI.push({component:0,pin:i,position:{x:centerX,y:centerY},radius:10,type:1});
    secondaryX=(i<chip.inputs?centerX+20:centerX-20);
    pI.push({component:0,pin:i,position:{x:secondaryX,y:centerY},radius:5,type:0});
    //ctx.beginPath();
    //ctx.arc(Math.floor(centerX), Math.floor(centerY), 10, 0, 2*Math.PI, false);
    (hoveredPin.component==0&&hoveredPin.pin==i&&hoveredPin.type==0) ? offset=2 : offset=0;
    
    fillStyle1=["black","red","grey","pink"][chip.pins[i]+offset];
    fillStyle2=(i<chip.inputs?["black","red","grey","pink"]:["black","red","black","red"])[chip.pins[i]+((hoveredPin.component==0&&hoveredPin.pin==i&&hoveredPin.type==1)?2:0)];
    //ctx.fill();
    drawLine({x:centerX,y:centerY},{x:secondaryX,y:centerY},1,["black","red"][chip.pins[i]]);
    drawCircle(centerX,centerY,10,fillStyle2);
    drawCircle(secondaryX,centerY,5,fillStyle1);
  })
	chip.zIndex.forEach(c=>{
    img = images[c.type];
    ctx.drawImage(img,c.position.x,c.position.y);
    c.pins.forEach((p,i)=>{
      //trueCenterY = (c.position.y+(c.position.y + c.height))/2
      centerX = c.position.x+img.width+5;
      otherpins = c.pins.length - c.inputs;
      pindex = i - c.inputs;
      if(i<c.inputs){
        centerX = c.position.x-5;
        if(["xor","nor","or"].includes(c.type)){
          centerX += 9;
        }
        otherpins = c.inputs;
        pindex=i;
      }
      ys = makeArr(c.position.y-(20/otherpins),c.position.y+img.height+(20/otherpins),otherpins+2);
      ys.shift();
      ys.pop();
      centerY = ys[pindex];
      pI.push({component:chip.subComponents.indexOf(c),pin:i,position:{x:centerX,y:centerY},radius:10,type:0});
      ctx.beginPath();
      ctx.arc(Math.floor(centerX), Math.floor(centerY), 5, 0, 2*Math.PI, false);
      (hoveredPin.component==chip.subComponents.indexOf(c)&&hoveredPin.pin==i) ? offset=2 : offset=0;
    ctx.fillStyle=["black","red","grey","pink"][c.pins[i]+offset];
      ctx.fill();
      

    });
  });
  pinImages=pI;  
  requestAnimationFrame(drawCanvas);
}