aiber-martin/plugins/cordova-plugin-file/www/browser/Preparing.js

/*
 *
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 *
*/

(function () {
    /* global require */

    // Only Chrome uses this file.
    if (!require('./isChrome')()) {
        return;
    }

    var channel = require('cordova/channel');
    var FileError = require('./FileError');
    var PERSISTENT_FS_QUOTA = 5 * 1024 * 1024;
    var filePluginIsReadyEvent = new Event('filePluginIsReady'); // eslint-disable-line no-undef

    var entryFunctionsCreated = false;
    var quotaWasRequested = false;
    var eventWasThrown = false;

    if (!window.requestFileSystem) {
        window.requestFileSystem = function (type, size, win, fail) {
            if (fail) {
                fail('Not supported');
            }
        };
    } else {
        window.requestFileSystem(window.TEMPORARY, 1, createFileEntryFunctions, function () {});
    }

    if (!window.resolveLocalFileSystemURL) {
        window.resolveLocalFileSystemURL = function (url, win, fail) {
            if (fail) {
                fail('Not supported');
            }
        };
    }

    // Resolves a filesystem entry by its path - which is passed either in standard (filesystem:file://) or
    // Cordova-specific (cdvfile://) universal way.
    // Aligns with specification: http://www.w3.org/TR/2011/WD-file-system-api-20110419/#widl-LocalFileSystem-resolveLocalFileSystemURL
    var nativeResolveLocalFileSystemURL = window.resolveLocalFileSystemURL || window.webkitResolveLocalFileSystemURL;
    window.resolveLocalFileSystemURL = function (url, win, fail) {
        /* If url starts with `cdvfile` then we need convert it to Chrome real url first:
          cdvfile://localhost/persistent/path/to/file -> filesystem:file://persistent/path/to/file */
        if (url.trim().substr(0, 7) === 'cdvfile') {
            /* Quirk:
            Plugin supports cdvfile://localhost (local resources) only.
            I.e. external resources are not supported via cdvfile. */
            if (url.indexOf('cdvfile://localhost') !== -1) {
                // Browser supports temporary and persistent only
                var indexPersistent = url.indexOf('persistent');
                var indexTemporary = url.indexOf('temporary');

                /* Chrome urls start with 'filesystem:' prefix. See quirk:
                   toURL function in Chrome returns filesystem:-prefixed path depending on application host.
                   For example, filesystem:file:///persistent/somefile.txt,
                   filesystem:http://localhost:8080/persistent/somefile.txt. */
                var prefix = 'filesystem:file:///';
                if (location.protocol !== 'file:') { // eslint-disable-line no-undef
                    prefix = 'filesystem:' + location.origin + '/'; // eslint-disable-line no-undef
                }

                var result;
                if (indexPersistent !== -1) {
                    // cdvfile://localhost/persistent/path/to/file -> filesystem:file://persistent/path/to/file
                    // or filesystem:http://localhost:8080/persistent/path/to/file
                    result = prefix + 'persistent' + url.substr(indexPersistent + 10);
                    nativeResolveLocalFileSystemURL(result, win, fail);
                    return;
                }

                if (indexTemporary !== -1) {
                    // cdvfile://localhost/temporary/path/to/file -> filesystem:file://temporary/path/to/file
                    // or filesystem:http://localhost:8080/temporary/path/to/file
                    result = prefix + 'temporary' + url.substr(indexTemporary + 9);
                    nativeResolveLocalFileSystemURL(result, win, fail);
                    return;
                }
            }

            // cdvfile other than local file resource is not supported
            if (fail) {
                fail(new FileError(FileError.ENCODING_ERR));
            }
        } else {
            nativeResolveLocalFileSystemURL(url, win, fail);
        }
    };

    function createFileEntryFunctions (fs) {
        fs.root.getFile('todelete_658674_833_4_cdv', {create: true}, function (fileEntry) {
            var fileEntryType = Object.getPrototypeOf(fileEntry);
            var entryType = Object.getPrototypeOf(fileEntryType);

            // Save the original method
            var origToURL = entryType.toURL;
            entryType.toURL = function () {
                var origURL = origToURL.call(this);
                if (this.isDirectory && origURL.substr(-1) !== '/') {
                    return origURL + '/';
                }
                return origURL;
            };

            entryType.toNativeURL = function () {
                console.warn("DEPRECATED: Update your code to use 'toURL'");
                return this.toURL();
            };

            entryType.toInternalURL = function () {
                if (this.toURL().indexOf('persistent') > -1) {
                    return 'cdvfile://localhost/persistent' + this.fullPath;
                }

                if (this.toURL().indexOf('temporary') > -1) {
                    return 'cdvfile://localhost/temporary' + this.fullPath;
                }
            };

            entryType.setMetadata = function (win, fail /*, metadata */) {
                if (fail) {
                    fail('Not supported');
                }
            };

            fileEntry.createWriter(function (writer) {
                var originalWrite = writer.write;
                var writerProto = Object.getPrototypeOf(writer);
                writerProto.write = function (blob) {
                    if (blob instanceof Blob) { // eslint-disable-line no-undef
                        originalWrite.apply(this, [blob]);
                    } else {
                        var realBlob = new Blob([blob]); // eslint-disable-line no-undef
                        originalWrite.apply(this, [realBlob]);
                    }
                };

                fileEntry.remove(function () { entryFunctionsCreated = true; }, function () { /* empty callback */ });
            });
        });
    }

    window.initPersistentFileSystem = function (size, win, fail) {
        if (navigator.webkitPersistentStorage) {
            navigator.webkitPersistentStorage.requestQuota(size, win, fail);
            return;
        }

        fail('This browser does not support this function');
    };

    window.isFilePluginReadyRaised = function () { return eventWasThrown; };

    window.initPersistentFileSystem(PERSISTENT_FS_QUOTA, function () {
        console.log('Persistent fs quota granted');
        quotaWasRequested = true;
    }, function (e) {
        console.log('Error occured while trying to request Persistent fs quota: ' + JSON.stringify(e));
    });

    channel.onCordovaReady.subscribe(function () {
        function dispatchEventIfReady () {
            if (entryFunctionsCreated && quotaWasRequested) {
                window.dispatchEvent(filePluginIsReadyEvent);
                eventWasThrown = true;
            } else {
                setTimeout(dispatchEventIfReady, 100);
            }
        }

        dispatchEventIfReady();
    }, false);
})();