1 files changed, 180 insertions, 0 deletions
diff --git a/toolkit/modules/LightweightThemeConsumer.jsm b/toolkit/modules/LightweightThemeConsumer.jsm
new file mode 100644
index 000000000..1dd4c976a
--- /dev/null
+++ b/toolkit/modules/LightweightThemeConsumer.jsm
@@ -0,0 +1,180 @@
+/* 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/. */
+
+this.EXPORTED_SYMBOLS = ["LightweightThemeConsumer"];
+
+const {utils: Cu} = Components;
+
+Cu.import("resource://gre/modules/XPCOMUtils.jsm");
+Cu.import("resource://gre/modules/Services.jsm");
+Cu.import("resource://gre/modules/AppConstants.jsm");
+
+XPCOMUtils.defineLazyModuleGetter(this, "LightweightThemeImageOptimizer",
+  "resource://gre/modules/addons/LightweightThemeImageOptimizer.jsm");
+
+XPCOMUtils.defineLazyModuleGetter(this, "PrivateBrowsingUtils",
+  "resource://gre/modules/PrivateBrowsingUtils.jsm");
+
+this.LightweightThemeConsumer =
+ function LightweightThemeConsumer(aDocument) {
+  this._doc = aDocument;
+  this._win = aDocument.defaultView;
+  this._footerId = aDocument.documentElement.getAttribute("lightweightthemesfooter");
+
+  if (PrivateBrowsingUtils.isWindowPrivate(this._win) &&
+      !PrivateBrowsingUtils.permanentPrivateBrowsing) {
+    return;
+  }
+
+  let screen = this._win.screen;
+  this._lastScreenWidth = screen.width;
+  this._lastScreenHeight = screen.height;
+
+  Services.obs.addObserver(this, "lightweight-theme-styling-update", false);
+
+  var temp = {};
+  Cu.import("resource://gre/modules/LightweightThemeManager.jsm", temp);
+  this._update(temp.LightweightThemeManager.currentThemeForDisplay);
+  this._win.addEventListener("resize", this);
+}
+
+LightweightThemeConsumer.prototype = {
+  _lastData: null,
+  _lastScreenWidth: null,
+  _lastScreenHeight: null,
+  // Whether the active lightweight theme should be shown on the window.
+  _enabled: true,
+  // Whether a lightweight theme is enabled.
+  _active: false,
+
+  enable: function() {
+    this._enabled = true;
+    this._update(this._lastData);
+  },
+
+  disable: function() {
+    // Dance to keep the data, but reset the applied styles:
+    let lastData = this._lastData
+    this._update(null);
+    this._enabled = false;
+    this._lastData = lastData;
+  },
+
+  getData: function() {
+    return this._enabled ? Cu.cloneInto(this._lastData, this._win) : null;
+  },
+
+  observe: function (aSubject, aTopic, aData) {
+    if (aTopic != "lightweight-theme-styling-update")
+      return;
+
+    this._update(JSON.parse(aData));
+  },
+
+  handleEvent: function (aEvent) {
+    let {width, height} = this._win.screen;
+
+    if (this._lastScreenWidth != width || this._lastScreenHeight != height) {
+      this._lastScreenWidth = width;
+      this._lastScreenHeight = height;
+      if (!this._active)
+        return;
+      this._update(this._lastData);
+      Services.obs.notifyObservers(this._win, "lightweight-theme-optimized",
+                                   JSON.stringify(this._lastData));
+    }
+  },
+
+  destroy: function () {
+    if (!PrivateBrowsingUtils.isWindowPrivate(this._win) ||
+        PrivateBrowsingUtils.permanentPrivateBrowsing) {
+      Services.obs.removeObserver(this, "lightweight-theme-styling-update");
+
+      this._win.removeEventListener("resize", this);
+    }
+
+    this._win = this._doc = null;
+  },
+
+  _update: function (aData) {
+    if (!aData) {
+      aData = { headerURL: "", footerURL: "", textcolor: "", accentcolor: "" };
+      this._lastData = aData;
+    } else {
+      this._lastData = aData;
+      aData = LightweightThemeImageOptimizer.optimize(aData, this._win.screen);
+    }
+    if (!this._enabled)
+      return;
+
+    let root = this._doc.documentElement;
+    let active = !!aData.headerURL;
+    let stateChanging = (active != this._active);
+
+    // We need to clear these either way: either because the theme is being removed,
+    // or because we are applying a new theme and the data might be bogus CSS,
+    // so if we don't reset first, it'll keep the old value.
+    root.style.removeProperty("color");
+    root.style.removeProperty("background-color");
+    if (active) {
+      root.style.color = aData.textcolor || "black";
+      root.style.backgroundColor = aData.accentcolor || "white";
+      let [r, g, b] = _parseRGB(this._doc.defaultView.getComputedStyle(root, "").color);
+      let luminance = 0.2125 * r + 0.7154 * g + 0.0721 * b;
+      root.setAttribute("lwthemetextcolor", luminance <= 110 ? "dark" : "bright");
+      root.setAttribute("lwtheme", "true");
+    } else {
+      root.removeAttribute("lwthemetextcolor");
+      root.removeAttribute("lwtheme");
+    }
+
+    this._active = active;
+
+    _setImage(root, active, aData.headerURL);
+    if (this._footerId) {
+      let footer = this._doc.getElementById(this._footerId);
+      footer.style.backgroundColor = active ? aData.accentcolor || "white" : "";
+      _setImage(footer, active, aData.footerURL);
+      if (active && aData.footerURL)
+        footer.setAttribute("lwthemefooter", "true");
+      else
+        footer.removeAttribute("lwthemefooter");
+    }
+
+    // On OS X, we extend the lightweight theme into the titlebar, which means setting
+    // the chromemargin attribute. Some XUL applications already draw in the titlebar,
+    // so we need to save the chromemargin value before we overwrite it with the value
+    // that lets us draw in the titlebar. We stash this value on the root attribute so
+    // that XUL applications have the ability to invalidate the saved value.
+    if (AppConstants.platform == "macosx" && stateChanging) {
+      if (!root.hasAttribute("chromemargin-nonlwtheme")) {
+        root.setAttribute("chromemargin-nonlwtheme", root.getAttribute("chromemargin"));
+      }
+
+      if (active) {
+        root.setAttribute("chromemargin", "0,-1,-1,-1");
+      } else {
+        let defaultChromemargin = root.getAttribute("chromemargin-nonlwtheme");
+        if (defaultChromemargin) {
+          root.setAttribute("chromemargin", defaultChromemargin);
+        } else {
+          root.removeAttribute("chromemargin");
+        }
+      }
+    }
+    Services.obs.notifyObservers(this._win, "lightweight-theme-window-updated",
+                                 JSON.stringify(aData));
+  }
+}
+
+function _setImage(aElement, aActive, aURL) {
+  aElement.style.backgroundImage =
+    (aActive && aURL) ? 'url("' + aURL.replace(/"/g, '\\"') + '")' : "";
+}
+
+function _parseRGB(aColorString) {
+  var rgb = aColorString.match(/^rgba?\((\d+), (\d+), (\d+)/);
+  rgb.shift();
+  return rgb.map(x => parseInt(x));
+}