/*
  gui functions take screen space coordinates
*/

gui.scissor_win = function() { gui.scissor(0,0,window.width,window.height); }

gui.input_lmouse_pressed = function() {
  if (gui.selected)
    gui.selected.action();
};

gui.input_s_pressed = function() {
  if (gui.selected?.down) {
    gui.selected.selected = false;
    gui.selected = gui.selected.down;
    gui.selected.selected = true;
  }
};

gui.input_w_pressed = function() {
  if (gui.selected?.up) {
    gui.selected.selected = false;
    gui.selected = gui.selected.up;
    gui.selected.selected = true;
  }
};

gui.input_enter_pressed = function() {
  if (gui.selected) {
    gui.selected.action();
  }
}

gui.controls = {};
gui.controls.toString = function() { return "gui controls"; };
gui.controls.update = function() { };

gui.controls.set_mum = function(mum)
{
  mum.selected = true;
  
  if (this.selected && this.selected !== mum)
    this.selected.selected = false;

  this.selected = mum;
}
gui.controls.check_bb = function(mum)
{
  if (bbox.pointin(mum.bb, input.mouse.screenpos()))
    gui.controls.set_mum(mum);
}
gui.controls.inputs = {};
gui.controls.inputs.fallthru = false;
gui.controls.inputs.mouse = {};
gui.controls.inputs.mouse.move = function(pos,dpos)
{
}
gui.controls.inputs.mouse.scroll = function(scroll)
{
}

gui.controls.check_submit = function() {
  if (this.selected && this.selected.action)
    this.selected.action(this.selected);
}

var Mum = {
    padding:[0,0], /* Each element inset with this padding on all sides */
    offset:[0,0],
    font: "fonts/c64.ttf",
    selectable: false,
    selected: false,
    font_size: 1,
    text_align: "left", /* left, center, right */
    scale: 1,
    angle: 0,
    anchor: [0,1],
    hovered: {},
    text_shadow: {
      pos: [0,0],
      color: Color.white,
    },
    text_outline: 1, /* outline in pixels */
    color: Color.white,
    margin: [0,0], /* Distance between elements for things like columns */
    width: 0,
    height: 0,
    max_width: Infinity,
    max_height: Infinity,
    image_repeat: false,
    image_repeat_offset: [0,0],
    debug: false, /* set to true to draw debug boxes */
    
  make(def) {
    var n = Object.create(this);
    Object.assign(n, def);
    return n;
  },

  prestart() {
    this.hovered.__proto__ = this;
  },

  start() {},

  extend(def) {
    var n = Object.create(this);
    Object.assign(n, def);
    var fn = function(def) {
      var p = n.make(def);
      p.prestart();
      p.start();
      return p;
    };
    fn._int = n;
    return fn;
  },
}

Mum.text = Mum.extend({
  draw(cursor = [0,0], cnt = Mum) {
    if (this.hide) return;
    if (this.selectable) gui.controls.check_bb(this);
    this.caret ??= -1;

/*    if (!this.bb)
      this.calc_bb(cursor);
    else
      this.update_bb(cursor);
*/
    var params = this.selected ? this.hovered : this;

    this.width = Math.min(params.max_width, cnt.max_width);

    this.calc_bb(cursor);
    this.height = this.wh.y;
    var aa = [0,1].sub(params.anchor);
    var pos = cursor.add(params.wh.scale(aa)).add(params.offset);
//    gui.font_set(params.font);
    render.text(params.str, pos, params.font_size, params.color, this.width, undefined, params.caret);
  },
  
  update_bb(cursor) {
    this.bb = bbox.move(this.bb, cursor.sub(this.wh.scale(this.anchor)));
  },
  
  calc_bb(cursor) {
    var bb = render.text_size(this.str, this.font_size, this.width);
    this.wh = bbox.towh(bb);
    var pos = cursor.add(this.wh.scale([0,1].sub(this.anchor))).add(this.offset);    
    this.bb = bbox.move(bb,pos.add([this.wh.x/2,0]));
  },
  start() {
    this.calc_bb([0,0]);
  },
});

Mum.button = Mum.text._int.extend({
 selectable: true,
 color: Color.blue,
 hovered:{
   color: Color.red
 },
 action() { console.warn("Button has no action."); },
});

Mum.window = Mum.extend({
  start() {
    this.wh = [this.width, this.height];
    this.bb = bbox.fromcwh([0,0], this.wh);
  },
  draw(cursor = [0,0], cnt = Mum) {
    var p = cursor.sub(this.wh.scale(this.anchor)).add(this.padding);    
    render.window(p,this.wh, this.color);
    this.bb = bbox.blwh(p, this.wh);
    gui.flush();
    gui.scissor(p.x,p.y,this.wh.x,this.wh.y);
    this.max_width = this.width;
    if (this.selectable) gui.controls.check_bb(this);
    var pos = [this.bb.l, this.bb.t].add(this.padding);
    this.items.forEach(function(item) {
      if (item.hide) return;
      item.draw(pos.slice(),this);
    }, this);
    gui.flush();
    gui.scissor_win();
  },
});

Mum.image = Mum.extend({
  start() {
    if (!this.path) {
      console.warn("Mum image needs a path.");
      this.draw = function(){};
      return;
    }

    var tex_wh = texture.dimensions(this.path);
    this.wh = tex_wh.slice();
    if (this.width !== 0) this.wh.x = this.width;
    if (this.height !== 0) this.wh.y = this.height;

    this.wh = wh.scale(this.scale);
    this.sendscale = [wh.x/tex_wh.x, wh.y/tex_wh.y];
  },
  
  draw(pos) {
    this.calc_bb(pos);
    gui_img(this.path, pos.sub(this.anchor.scale([this.width, this.height])), this.sendscale, this.angle, this.image_repeat, this.image_repeat_offset, this.color);
  },

  calc_bb(pos) {
    this.bb = bbox.fromcwh(this.wh.scale([0.5,0.5]), wh);
    this.bb = bbox.move(this.bb, pos.sub(this.wh.scale(this.anchor)));
  }
});

Mum.column = Mum.extend({
  draw(cursor = [0,0], cnt = Mum) {
    if (this.hide) return;
    cursor = cursor.add(this.offset);
    this.max_width = cnt.width;
    
    this.items.forEach(function(item) {
      if (item.hide) return;
      item.draw(cursor, this);
      cursor.y -= item.height;
      cursor.y -= this.padding.y;
    }, this);
  },
});

Mum.debug_colors = {
  bounds: Color.red.slice(),
  margin: Color.blue.slice(),
  padding: Color.green.slice()
};

Object.values(Mum.debug_colors).forEach(function(v) { v.a = 100; });

return { Mum };