summaryrefslogtreecommitdiffstats
path: root/browser/base/content/newtab/updater.js
blob: 2bab74d708574fc383afc4dfb99cf9f9ed571e09 (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
#ifdef 0
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this file,
 * You can obtain one at http://mozilla.org/MPL/2.0/. */
#endif

/**
 * This singleton provides functionality to update the current grid to a new
 * set of pinned and blocked sites. It adds, moves and removes sites.
 */
var gUpdater = {
  /**
   * Updates the current grid according to its pinned and blocked sites.
   * This removes old, moves existing and creates new sites to fill gaps.
   * @param aCallback The callback to call when finished.
   */
  updateGrid: function Updater_updateGrid(aCallback) {
    let links = gLinks.getLinks().slice(0, gGrid.cells.length);

    // Find all sites that remain in the grid.
    let sites = this._findRemainingSites(links);

    // Remove sites that are no longer in the grid.
    this._removeLegacySites(sites, () => {
      // Freeze all site positions so that we can move their DOM nodes around
      // without any visual impact.
      this._freezeSitePositions(sites);

      // Move the sites' DOM nodes to their new position in the DOM. This will
      // have no visual effect as all the sites have been frozen and will
      // remain in their current position.
      this._moveSiteNodes(sites);

      // Now it's time to animate the sites actually moving to their new
      // positions.
      this._rearrangeSites(sites, () => {
        // Try to fill empty cells and finish.
        this._fillEmptyCells(links, aCallback);

        // Update other pages that might be open to keep them synced.
        gAllPages.update(gPage);
      });
    });
  },

  /**
   * Takes an array of links and tries to correlate them to sites contained in
   * the current grid. If no corresponding site can be found (i.e. the link is
   * new and a site will be created) then just set it to null.
   * @param aLinks The array of links to find sites for.
   * @return Array of sites mapped to the given links (can contain null values).
   */
  _findRemainingSites: function Updater_findRemainingSites(aLinks) {
    let map = {};

    // Create a map to easily retrieve the site for a given URL.
    gGrid.sites.forEach(function (aSite) {
      if (aSite)
        map[aSite.url] = aSite;
    });

    // Map each link to its corresponding site, if any.
    return aLinks.map(function (aLink) {
      return aLink && (aLink.url in map) && map[aLink.url];
    });
  },

  /**
   * Freezes the given sites' positions.
   * @param aSites The array of sites to freeze.
   */
  _freezeSitePositions: function Updater_freezeSitePositions(aSites) {
    aSites.forEach(function (aSite) {
      if (aSite)
        gTransformation.freezeSitePosition(aSite);
    });
  },

  /**
   * Moves the given sites' DOM nodes to their new positions.
   * @param aSites The array of sites to move.
   */
  _moveSiteNodes: function Updater_moveSiteNodes(aSites) {
    let cells = gGrid.cells;

    // Truncate the given array of sites to not have more sites than cells.
    // This can happen when the user drags a bookmark (or any other new kind
    // of link) onto the grid.
    let sites = aSites.slice(0, cells.length);

    sites.forEach(function (aSite, aIndex) {
      let cell = cells[aIndex];
      let cellSite = cell.site;

      // The site's position didn't change.
      if (!aSite || cellSite != aSite) {
        let cellNode = cell.node;

        // Empty the cell if necessary.
        if (cellSite)
          cellNode.removeChild(cellSite.node);

        // Put the new site in place, if any.
        if (aSite)
          cellNode.appendChild(aSite.node);
      }
    }, this);
  },

  /**
   * Rearranges the given sites and slides them to their new positions.
   * @param aSites The array of sites to re-arrange.
   * @param aCallback The callback to call when finished.
   */
  _rearrangeSites: function Updater_rearrangeSites(aSites, aCallback) {
    let options = {callback: aCallback, unfreeze: true};
    gTransformation.rearrangeSites(aSites, options);
  },

  /**
   * Removes all sites from the grid that are not in the given links array or
   * exceed the grid.
   * @param aSites The array of sites remaining in the grid.
   * @param aCallback The callback to call when finished.
   */
  _removeLegacySites: function Updater_removeLegacySites(aSites, aCallback) {
    let batch = [];

    // Delete sites that were removed from the grid.
    gGrid.sites.forEach(function (aSite) {
      // The site must be valid and not in the current grid.
      if (!aSite || aSites.indexOf(aSite) != -1)
        return;

      batch.push(new Promise(resolve => {
        // Fade out the to-be-removed site.
        gTransformation.hideSite(aSite, function () {
          let node = aSite.node;

          // Remove the site from the DOM.
          node.parentNode.removeChild(node);
          resolve();
        });
      }));
    });

    Promise.all(batch).then(aCallback);
  },

  /**
   * Tries to fill empty cells with new links if available.
   * @param aLinks The array of links.
   * @param aCallback The callback to call when finished.
   */
  _fillEmptyCells: function Updater_fillEmptyCells(aLinks, aCallback) {
    let {cells, sites} = gGrid;

    // Find empty cells and fill them.
    Promise.all(sites.map((aSite, aIndex) => {
      if (aSite || !aLinks[aIndex])
        return null;

      return new Promise(resolve => {
        // Create the new site and fade it in.
        let site = gGrid.createSite(aLinks[aIndex], cells[aIndex]);

        // Set the site's initial opacity to zero.
        site.node.style.opacity = 0;

        // Flush all style changes for the dynamically inserted site to make
        // the fade-in transition work.
        window.getComputedStyle(site.node).opacity;
        gTransformation.showSite(site, resolve);
      });
    })).then(aCallback).catch(console.exception);
  }
};