import Ember from 'ember';

export var PositionEnum = {
  HIDDEN: 'hidden',
  NORMAL: 'normal',
  MINIMIZED: 'minimized',
  FULLSCREEN: 'fullscreen'
};

export default Ember.Controller.extend(Ember.Evented, {
  content: null,
  position: PositionEnum.HIDDEN,

  visible: Ember.computed.or('normal', 'minimized', 'fullscreen'),
  normal: Ember.computed.equal('position', PositionEnum.NORMAL),
  minimized: Ember.computed.equal('position', PositionEnum.MINIMIZED),
  fullscreen: Ember.computed.equal('position', PositionEnum.FULLSCREEN),

  // Switch out the composer's content for a new component. The old
  // component will be given the opportunity to abort the switch. Note:
  // there appears to be a bug in Ember where the content binding won't
  // update in the view if we switch the value out immediately. As a
  // workaround, we set it to null, and then set it to its new value in the
  // next run loop iteration.
  switchContent: function(newContent) {
    var composer = this;
    this.confirmExit().then(function() {
      composer.set('content', null);
      Ember.run.next(function() {
        newContent.composer = composer;
        composer.set('content', newContent);
      });
    });
  },

  // Ask the content component if it's OK to close it, and give it the
  // opportunity to abort. The content component must respond to the
  // `willExit(abort)` action, and call `abort()` if we should not proceed.
  confirmExit: function() {
    var composer = this;
    var promise = new Ember.RSVP.Promise(function(resolve, reject) {
      var content = composer.get('content');
      if (content) {
        content.send('willExit', reject);
      }
      resolve();
    });
    return promise;
  },

  actions: {
    show: function() {
      var composer = this;

      // We do this in the next run loop because we need to wait for new
      // content to be switched in. See `switchContent` above.
      Ember.run.next(function() {
        composer.set('position', PositionEnum.NORMAL);
        composer.trigger('focus');
      });
    },

    hide: function() {
      this.set('position', PositionEnum.HIDDEN);
    },

    clearContent: function() {
      this.set('content', null);
    },

    close: function() {
      var composer = this;
      this.confirmExit().then(function() {
        composer.send('hide');
      });
    },

    minimize: function() {
      if (this.get('position') !== PositionEnum.HIDDEN) {
        this.set('position', PositionEnum.MINIMIZED);
      }
    },

    fullscreen: function() {
      if (this.get('position') !== PositionEnum.HIDDEN) {
        this.set('position', PositionEnum.FULLSCREEN);
        this.trigger('focus');
      }
    },

    exitFullscreen: function() {
      if (this.get('position') === PositionEnum.FULLSCREEN) {
        this.set('position', PositionEnum.NORMAL);
        this.trigger('focus');
      }
    }
  }

});