const canvas = document.getElementById("canvas");

var canvas_width = canvas.offsetWidth;
var canvas_height = canvas.offsetHeight;

function sort(array) {
  return array.sort(function(a, b) {
    return a - b;
  })
}

const grid_line = {
  stroke: '#ddd',
}

// first we need to create a stage
var stage = new Konva.Stage({
  container: canvas,
});

var agent;
var map_layer = new Konva.Layer();
var map_group = new Konva.Group();
var grid_group = new Konva.Group();
var tile_group = new Konva.Group();
var agent_group = new Konva.Group();

var padding;

map_layer.add(map_group);
stage.add(map_layer);

function init_stage() {
  stage.width(canvas_width);
  stage.height(canvas_height);
  map_group.width(stage.width() * 0.6);
  map_group.height(stage.height() * 0.9);
  map_group.setX(stage.width() * 0.2);
  map_group.setY(stage.height() / 2 - (stage.height() * 0.45));
}

function draw_agent(state) {
  // cleanup
  agent_group.remove();
  agent_group = new Konva.Group();

  agent = {
    "konva": new Konva.RegularPolygon({
      offset: {
        x: -padding / 2,
        y: -padding / 2
      },
      sides: 5,
      radius: padding / 3,
      fill: '#00D2FF',
      stroke: 'black',
      strokeWidth: padding / 50
    }),
    "target_x": undefined,
    "target_y": undefined,
    "todos": [],
    "_padding": padding,
    set padding(pad){
      this._padding = pad;
      this.konva.offset({x: -padding / 2, y: -padding / 2});
      this.konva.radius(padding / 3);
      this.konva.strokeWidth(padding / 50);
    },
    get x() {
      return Math.floor(this.konva.getX() / this._padding);
    },
    set x(pos) {
      // this.target_x = sort([0, pos, map[0].length - 1])[1] * this._padding;
      this.konva.setX(sort([0, pos, map[0].length - 1])[1] * this._padding);
      map_layer.draw();
    },
    get y() {
      return Math.floor(this.konva.getY() / this._padding);
    },
    set y(pos) {
      // this.target_y = sort([0, pos, map.length - 1])[1] * this._padding;
      this.konva.setY(sort([0, pos, map.length - 1])[1] * this._padding);
      map_layer.draw();
    },
    do_action(action, animate=false){
      var y = this.y;
      var x = this.x;
      var fun;
      switch (action) {
        case dir.UP:
          y--;
          fun = function () {return [this.x,this.y-1]}.bind(this);
          break;
        case dir.RIGHT:
          x++;
          fun = function () {return [this.x+1,this.y]}.bind(this);
          break;
        case dir.DOWN:
          y++;
          fun = function () {return [this.x,this.y+1]}.bind(this);
          break;
        case dir.LEFT:
          x--;
          fun = function () {return [this.x-1,this.y]}.bind(this);
          break;
      }
      if (animate){
        console.log(fun);
        this.todos.push(fun);
        console.log(this.todos);
      } else {
        this.todos = [];
        this.target_x = undefined;
        this.target_y = undefined;
        this.x = x;
        this.y = y;
      }
    },
    set_state(state, animate=false){
      let y = Math.floor(state/map[0].length);
      let x = state%map[0].length;
      if (animate){
        this.todos.push([x,y])
      } else {
        this.todos = [];
        this.target_x = undefined;
        this.target_y = undefined;
        this.x = x;
        this.y = y;
      }
    },
    "animation": function () {
      return new Konva.Animation(function(frame) {
        if (this.target_x === undefined || this.target_y === undefined) {
          if (this.todos.length == 0){
            return
          }
          var current = this.todos.shift();
          if (current.length == 2){
            [this.target_x,this.target_y] = current;
          } else {
            [this.target_x,this.target_y] = current();
          }
        }
        var x = sort([0, this.target_x, map[1].length - 1])[1] * this._padding;
        var y = sort([0, this.target_y, map.length - 1])[1] * this._padding;
        var vec = [x-this.konva.getX(),y-this.konva.getY()];
        const length = Math.sqrt(vec[0]**2+vec[1]**2);
        var step = frame.timeDiff*(padding/100);
        if (length < step){
          this.konva.setX(x);
          this.konva.setY(y);
          this.target_x = undefined;
          this.target_y = undefined;
        } else {
          vec[0] = vec[0]/length;
          vec[1] = vec[1]/length;
          this.konva.setX(this.konva.getX()+vec[0]*step);
          this.konva.setY(this.konva.getY()+vec[1]*step);
        }
      }.bind(this), map_layer);
    }
  }
  var anim = agent.animation();
  agent.set_state(state);
  anim.start();
  agent_group.add(agent.konva);
  map_group.add(agent_group);
}

function update_agent(state, animate=false) {
  agent.padding = padding;
  agent.set_state(state, animate);
}

function draw_map(map) {
  grid_group.remove();
  grid_group = new Konva.Group();
  tile_group.remove();
  tile_group = new Konva.Group();

  init_stage();

  padding = Math.min(map_group.height() / map.length, map_group.width() / map[0].length);
  var strokeW = padding/50;
  const offset = strokeW / 2;
  // x
  for (let i = 0; i < map[0].length + 1; i++) {
    grid_group.add(new Konva.Line({
      points: [Math.round(i * padding), -offset, Math.round(i * padding), padding * map.length + offset],
      strokeWidth: strokeW,
      ...grid_line
    }));
    grid_group.width(Math.round(i * padding));
  }
  // y
  for (let j = 0; j < map.length + 1; j++) {
    grid_group.add(new Konva.Line({
      points: [-offset, Math.round(j * padding), padding * map[0].length + offset, Math.round(j * padding)],
      strokeWidth: strokeW,
      ...grid_line
    }));
    grid_group.height(Math.round(j * padding));
  }

  for (var idy in map) {
    for (var idx in map[idy]) {
      const layout = {
        x: padding * idx + offset,
        y: padding * idy + offset,
        width: padding - 2 * offset,
        height: padding - 2 * offset,
        // stroke: '#CF6412',
        // strokeWidth: 4
      };
      if (map[idy][idx] == tile.dangerous) {
        tile_group.add(new Konva.Rect({
          ...layout,
          fill: '#FF7B17',
          opacity: 1,
        }))
      } else if (map[idy][idx] == tile.end) {
        tile_group.add(new Konva.Rect({
          ...layout,
          fill: '#0eb500',
          opacity: 0.5,
        }))
      } else if (map[idy][idx] == tile.start) {
        tile_group.add(new Konva.Rect({
          ...layout,
          fill: '#ff0008',
          opacity: 0.5,
        }))
      }
    }
  }

  map_group.offset({
    x: -(map_group.width() - grid_group.width()) / 2,
    y: -(map_group.height() - grid_group.height()) / 2,
  });

  map_group.add(grid_group);
  map_group.add(tile_group);

  map_layer.draw();
}

window.addEventListener('resize', function() {
  canvas_width = canvas.offsetWidth;
  canvas_height = canvas.offsetHeight;
  draw_map(map);
  draw_agent(machine.state);
});

draw_map(map)
draw_agent(machine.state)