summaryrefslogtreecommitdiffstats
path: root/client/lib/popup.js
blob: 46c137e8ed0bf8c76e26ee1a0428c4d8fc7b546a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
// A simple tracker dependency that we invalidate every time the window is
// resized. This is used to reactively re-calculate the popup position in case
// of a window resize.
var windowResizeDep = new Tracker.Dependency();
$(window).on('resize', function() { windowResizeDep.changed(); });

Popup = {
  /// This function returns a callback that can be used in an event map:
  ///
  ///   Template.tplName.events({
  ///     'click .elementClass': Popup.open("popupName")
  ///   });
  ///
  /// The popup inherit the data context of its parent.
  open: function(name) {
    var self = this;
    var popupName = name + 'Popup';

    return function(evt) {
      // If a popup is already openened, clicking again on the opener element
      // should close it -- and interupt the current `open` function.
      if (self.isOpen() &&
          self._getTopStack().openerElement === evt.currentTarget) {
        return self.close();
      }

      // We determine the `openerElement` (the DOM element that is being clicked
      // and the one we take in reference to position the popup) from the event
      // if the popup has no parent, or from the parent `openerElement` if it
      // has one. This allows us to position a sub-popup exactly at the same
      // position than its parent.
      var openerElement;
      if (self._hasPopupParent()) {
        openerElement = self._getTopStack().openerElement;
      } else {
        self._stack = [];
        openerElement = evt.currentTarget;
      }

      // We modify the event to prevent the popup being closed when the event
      // bubble up to the document element.
      evt.originalEvent.clickInPopup = true;
      evt.preventDefault();

      // We push our popup data to the stack. The top of the stack is always
      // used as the data source for our current popup.
      self._stack.push({
        __isPopup: true,
        popupName: popupName,
        hasPopupParent: self._hasPopupParent(),
        title: self._getTitle(popupName),
        openerElement: openerElement,
        offset: self._getOffset(openerElement),
        dataContext: this.currentData && this.currentData() || this
      });

      // If there are no popup currently opened we use the Blaze API to render
      // one into the DOM. We use a reactive function as the data parameter that
      // return the the complete along with its top element and depends on our
      // internal dependency that is being invalidated every time the top
      // element of the stack has changed and we want to update the popup.
      //
      // Otherwise if there is already a popup open we just need to invalidate
      // our internal dependency, and since we just changed the top element of
      // our internal stack, the popup will be updated with the new data.
      if (! self.isOpen()) {
        self.current = Blaze.renderWithData(self.template, function() {
          self._dep.depend();
          return _.extend(self._stack[self._stack.length - 1], {
            stack: self._stack,
            containerTranslation: (self._stack.length - 1) * -300
          });
        }, document.body);

      } else {
        self._dep.changed();
      }
    };
  },

  /// This function returns a callback that can be used in an event map:
  ///
  ///   Template.tplName.events({
  ///     'click .elementClass': Popup.afterConfirm("popupName", function() {
  ///       // What to do after the user has confirmed the action
  ///     })
  ///   });
  afterConfirm: function(name, action) {
    var self = this;

    return function(evt, tpl) {
      var context = this;
      context.__afterConfirmAction = action;
      self.open(name).call(context, evt, tpl);
    };
  },

  /// The public reactive state of the popup.
  isOpen: function() {
    this._dep.changed();
    return !! this.current;
  },

  /// In case the popup was opened from a parent popup we can get back to it
  /// with this `Popup.back()` function. You can go back several steps at once
  /// by providing a number to this function, e.g. `Popup.back(2)`. In this case
  /// intermediate popup won't even be rendered on the DOM. If the number of
  /// steps back is greater than the popup stack size, the popup will be closed.
  back: function(n) {
    n = n || 1;
    var self = this;
    if (self._stack.length > n) {
      _.times(n, function() { self._stack.pop(); });
      self._dep.changed();
    } else {
      self.close();
    }
  },

  /// Close the current opened popup.
  close: function() {
    if (this.isOpen()) {
      Blaze.remove(this.current);
      this.current = null;
      this._stack = [];
    }
  },

  // The template we use for every popup
  template: Template.popup,

  // We only want to display one popup at a time and we keep the view object in
  // this `Popup._current` variable. If there is no popup currently opened the
  // value is `null`.
  _current: null,

  // It's possible to open a sub-popup B from a popup A. In that case we keep
  // the data of popup A so we can return back to it. Every time we open a new
  // popup the stack grows, every time we go back the stack decrease, and if we
  // close the popup the stack is reseted to the empty stack [].
  _stack: [],

  // We invalidate this internal dependency every time the top of the stack has
  // changed and we want to render a popup with the new top-stack data.
  _dep: new Tracker.Dependency(),

  // An utility fonction that returns the top element of the internal stack
  _getTopStack: function() {
    return this._stack[this._stack.length - 1];
  },

  // We use the blaze API to determine if the current popup has been opened from
  // a parent popup. The number we give to the `Template.parentData` has been
  // determined experimentally and is susceptible to change if you modify the
  // `Popup.template`
  _hasPopupParent: function() {
    var tryParentData = Template.parentData(3);
    return !! (tryParentData && tryParentData.__isPopup);
  },

  // We automatically calculate the popup offset from the reference element
  // position and dimensions. We also reactively use the window dimensions to
  // ensure that the popup is always visible on the screen.
  _getOffset: function(element) {
    var $element = $(element);
    return function() {
      windowResizeDep.depend();
      var offset = $element.offset();
      var popupWidth = 300 + 15;
      return {
        left: Math.min(offset.left, $(window).width() - popupWidth),
        top: offset.top + $element.outerHeight()
      };
    };
  },

  // We get the title from the translation files. Instead of returning the
  // result, we return a function that compute the result and since `TAPi18n.__`
  // is a reactive data source, the title will be changed reactively.
  _getTitle: function(popupName) {
    return function() {
      var translationKey = popupName + '-title';

      // XXX There is no public API to check if there is an available
      // translation for a given key. So we try to translate the key and if the
      // translation output equals the key input we deduce that no translation
      // was available and returns `false`. There is a (small) risk a false
      // positives.
      var title = TAPi18n.__(translationKey);
      return title !== translationKey ? title : false;
    };
  }
};

// We automatically close a potential opened popup on any left click on the
// document. To avoid closing it unexpectedly we modify the bubbled event in
// case the click event happen in the popup or in  a button that open a popup.
$(document).on('click', function(evt) {
  if (evt.which === 1 && ! (evt.originalEvent &&
      evt.originalEvent.clickInPopup)) {
    Popup.close();
  }
});

// Press escape to close the popup.
var bindPopup = function(f) { return _.bind(f, Popup); };
EscapeActions.register('popup',
  bindPopup(Popup.close),
  bindPopup(Popup.isOpen)
);