gecko/toolkit/mozapps/extensions/LightweightThemeImageOptimizer.jsm
Kyle Huey 1482122303 Bug 798491: Add an option to stick all chrome JSMs/JS components in the same compartment. r=mrbkap,philikon
--HG--
extra : rebase_source : 98337b6a8c07d05e8c961a452dd05a7d75c3c60b
2012-10-31 09:13:28 -07:00

187 lines
5.3 KiB
JavaScript

/* 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/. */
"use strict";
this.EXPORTED_SYMBOLS = ["LightweightThemeImageOptimizer"];
const Cu = Components.utils;
const Ci = Components.interfaces;
Cu.import("resource://gre/modules/XPCOMUtils.jsm");
XPCOMUtils.defineLazyModuleGetter(this, "Services",
"resource://gre/modules/Services.jsm");
XPCOMUtils.defineLazyModuleGetter(this, "FileUtils",
"resource://gre/modules/FileUtils.jsm");
const ORIGIN_TOP_RIGHT = 1;
const ORIGIN_BOTTOM_LEFT = 2;
this.LightweightThemeImageOptimizer = {
optimize: function LWTIO_optimize(aThemeData, aScreen) {
let data = Utils.createCopy(aThemeData);
if (!data.headerURL) {
return data;
}
data.headerURL = ImageCropper.getCroppedImageURL(
data.headerURL, aScreen, ORIGIN_TOP_RIGHT);
if (data.footerURL) {
data.footerURL = ImageCropper.getCroppedImageURL(
data.footerURL, aScreen, ORIGIN_BOTTOM_LEFT);
}
return data;
},
purge: function LWTIO_purge() {
let dir = FileUtils.getDir("ProfD", ["lwtheme"]);
dir.followLinks = false;
try {
dir.remove(true);
} catch (e) {}
}
};
Object.freeze(LightweightThemeImageOptimizer);
let ImageCropper = {
_inProgress: {},
getCroppedImageURL:
function ImageCropper_getCroppedImageURL(aImageURL, aScreen, aOrigin) {
// We can crop local files, only.
if (!aImageURL.startsWith("file://")) {
return aImageURL;
}
// Generate the cropped image's file name using its
// base name and the current screen size.
let uri = Services.io.newURI(aImageURL, null, null);
let file = uri.QueryInterface(Ci.nsIFileURL).file;
// Make sure the source file exists.
if (!file.exists()) {
return aImageURL;
}
let fileName = file.leafName + "-" + aScreen.width + "x" + aScreen.height;
let croppedFile = FileUtils.getFile("ProfD", ["lwtheme", fileName]);
// If we have a local file that is not in progress, return it.
if (croppedFile.exists() && !(croppedFile.path in this._inProgress)) {
let fileURI = Services.io.newFileURI(croppedFile);
// Copy the query part to avoid wrong caching.
fileURI.QueryInterface(Ci.nsIURL).query = uri.query;
return fileURI.spec;
}
// Crop the given image in the background.
this._crop(uri, croppedFile, aScreen, aOrigin);
// Return the original image while we're waiting for the cropped version
// to be written to disk.
return aImageURL;
},
_crop: function ImageCropper_crop(aURI, aTargetFile, aScreen, aOrigin) {
let inProgress = this._inProgress;
inProgress[aTargetFile.path] = true;
function resetInProgress() {
delete inProgress[aTargetFile.path];
}
ImageFile.read(aURI, function crop_readImageFile(aInputStream, aContentType) {
if (aInputStream && aContentType) {
let image = ImageTools.decode(aInputStream, aContentType);
if (image && image.width && image.height) {
let stream = ImageTools.encode(image, aScreen, aOrigin, aContentType);
if (stream) {
ImageFile.write(aTargetFile, stream, resetInProgress);
return;
}
}
}
resetInProgress();
});
}
};
let ImageFile = {
read: function ImageFile_read(aURI, aCallback) {
this._netUtil.asyncFetch(aURI, function read_asyncFetch(aInputStream, aStatus, aRequest) {
if (Components.isSuccessCode(aStatus) && aRequest instanceof Ci.nsIChannel) {
let channel = aRequest.QueryInterface(Ci.nsIChannel);
aCallback(aInputStream, channel.contentType);
} else {
aCallback();
}
});
},
write: function ImageFile_write(aFile, aInputStream, aCallback) {
let fos = FileUtils.openSafeFileOutputStream(aFile);
this._netUtil.asyncCopy(aInputStream, fos, function write_asyncCopy(aResult) {
FileUtils.closeSafeFileOutputStream(fos);
// Remove the file if writing was not successful.
if (!Components.isSuccessCode(aResult)) {
try {
aFile.remove(false);
} catch (e) {}
}
aCallback();
});
}
};
XPCOMUtils.defineLazyModuleGetter(ImageFile, "_netUtil",
"resource://gre/modules/NetUtil.jsm", "NetUtil");
let ImageTools = {
decode: function ImageTools_decode(aInputStream, aContentType) {
let outParam = {value: null};
try {
this._imgTools.decodeImageData(aInputStream, aContentType, outParam);
} catch (e) {}
return outParam.value;
},
encode: function ImageTools_encode(aImage, aScreen, aOrigin, aContentType) {
let stream;
let width = Math.min(aImage.width, aScreen.width);
let height = Math.min(aImage.height, aScreen.height);
let x = aOrigin == ORIGIN_TOP_RIGHT ? aImage.width - width : 0;
try {
stream = this._imgTools.encodeCroppedImage(aImage, aContentType, x, 0,
width, height);
} catch (e) {}
return stream;
}
};
XPCOMUtils.defineLazyServiceGetter(ImageTools, "_imgTools",
"@mozilla.org/image/tools;1", "imgITools");
let Utils = {
createCopy: function Utils_createCopy(aData) {
let copy = {};
for (let [k, v] in Iterator(aData)) {
copy[k] = v;
}
return copy;
}
};