<!--
// Copyright 2014 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
-->
<import src="sky-button.sky" as="SkyButton" />

<sky-element
    name="sky-radio"
    attributes="selected:boolean, group:string"
    on-click="handleClick">
<template>
  <style>
    :host {
      display: inline-block;
      -webkit-user-select: none;
      width: 14px;
      height: 14px;
      border-radius: 7px;
      border: 1px solid blue;
      margin: 0 5px;
    }
    :host([highlight=true]) box {
      background-color: orange;
    }
    dot {
      -webkit-user-select: none;
      width: 10px;
      height: 10px;
      border-radius: 5px;
      background-color: black;
      margin: 2px;
    }
  </style>
  <template if="{{ selected }}">
    <dot />
  </template>
</template>
<script>
const kControllerMap = new WeakMap();

class RadioGroupController {
  static forRadio(radio) {
    var scope = radio.ownerScope;
    var controller = kControllerMap.get(scope);
    if (!controller)
      kControllerMap.set(scope, new RadioGroupController());
    return kControllerMap.get(scope);
  }
  constructor() {
    this.radios = new Set();
  }
  addRadio(radio) {
    this.radios.add(radio);
    // If this new radio is default-selected, take selection from the group.
    if (radio.selected)
      this.takeSelectionFromGroup(radio);
  }
  removeRadio(radio) {
    this.radios.remove(radio);
  }
  takeSelectionFromGroup(selectedRadio) {
    // Emtpy/null/undefined group means an isolated radio.
    if (!selectedRadio.group)
      return;
    this.radios.forEach(function(radio) {
      if (selectedRadio === radio)
        return;
      if (radio.group != selectedRadio.group)
        return;
      radio.selected = false;
    });
  }
};

module.exports = class extends SkyButton {
  created() {
    super.created();

    this.controller = null;
  }
  attached() {
    super.attached();
    this.controller = RadioGroupController.forRadio(this);
    this.controller.addRadio(this);
  }
  detached() {
    super.detached();
    this.controller.removeRadio(this);
    this.controller = null;
  }
  selectedChanged(oldValue, newValue) {
    if (newValue && this.controller)
      this.controller.takeSelectionFromGroup(this);
  }
  groupChanged(oldValue, newValue) {
    if (this.selected && this.controller)
      this.controller.takeSelectionFromGroup(this);
  }
  handleClick() {
    this.selected = true;
  }
}.register();
</script>
</sky-element>