Stackedit/js/synchronizer.js
2013-04-13 01:05:59 +01:00

355 lines
11 KiB
JavaScript

define(["jquery", "google-helper", "dropbox-helper"], function($, googleHelper, dropboxHelper) {
var synchronizer = {};
// Dependencies
var core = undefined;
var fileManager = undefined;
// Used to know the providers we are connected to
synchronizer.useGoogleDrive = false;
synchronizer.useDropbox = false;
// Used to know if user can force synchronization
var uploadPending = false;
// Allows external modules to update uploadPending flag
synchronizer.notifyChange = function(fileIndex) {
// Check that file has synchronized locations
if(localStorage[fileIndex + ".sync"].length !== 1) {
uploadPending = true;
synchronizer.updateSyncButton();
}
};
// Used to enable/disable the synchronization button
synchronizer.updateSyncButton = function() {
if(syncRunning === true || uploadPending === false || core.isOffline) {
$(".action-force-sync").addClass("disabled");
}
else {
$(".action-force-sync").removeClass("disabled");
}
};
// Force the synchronization
synchronizer.forceSync = function() {
lastSync = 0;
synchronizer.sync();
};
// Recursive function to upload a single file on multiple locations
var uploadFileSyncIndexList = [];
var uploadContent = undefined;
var uploadContentCRC = undefined;
var uploadTitle = undefined;
var uploadTitleCRC = undefined;
function locationUp(callback) {
// No more synchronized location for this document
if (uploadFileSyncIndexList.length === 0) {
fileUp(callback);
return;
}
// Dequeue a synchronized location
var fileSyncIndex = uploadFileSyncIndexList.pop();
if(!fileSyncIndex) {
locationUp(callback);
return;
}
// Skip if CRC has not changed
var syncContentCRC = localStorage[fileSyncIndex + ".contentCRC"];
var syncTitleCRC = localStorage[fileSyncIndex + ".titleCRC"];
if(uploadContentCRC == syncContentCRC && (syncTitleCRC === undefined || uploadTitleCRC == syncTitleCRC)) {
locationUp(callback);
return;
}
// If upload is going to run, go for an other upload cycle at the end
uploadCycle = true;
// When page is refreshed, this flag is false but should be true here
uploadPending = true;
// Try to find the provider
if (fileSyncIndex.indexOf(SYNC_PROVIDER_GDRIVE) === 0) {
var id = fileSyncIndex.substring(SYNC_PROVIDER_GDRIVE.length);
googleHelper.upload(id, undefined, uploadTitle, uploadContent, function(result) {
if (result !== undefined) {
localStorage[fileSyncIndex + ".contentCRC"] = uploadContentCRC;
localStorage[fileSyncIndex + ".titleCRC"] = uploadTitleCRC;
locationUp(callback);
return;
}
// If error we abort the synchronization (retry later)
callback("abort");
return;
});
} else if (fileSyncIndex.indexOf(SYNC_PROVIDER_DROPBOX) === 0) {
var path = fileSyncIndex.substring(SYNC_PROVIDER_DROPBOX.length);
path = decodeURIComponent(path);
dropboxHelper.upload(path, uploadContent, function(result) {
if (result !== undefined) {
localStorage[fileSyncIndex + ".contentCRC"] = uploadContentCRC;
locationUp(callback);
return;
}
// If error we abort the synchronization (retry later)
callback("abort");
return;
});
} else {
// This should never happen
console.error("Invalid fileSyncIndex: " + fileSyncIndex);
callback("error");
}
}
// Recursive function to upload multiple files
var uploadFileIndexList = [];
function fileUp(callback) {
// No more fileIndex to synchronize
if (uploadFileIndexList.length === 0) {
syncUp(callback);
return;
}
// Dequeue a fileIndex
var fileIndex = uploadFileIndexList.pop();
var fileSyncIndexes = localStorage[fileIndex + ".sync"];
if(!fileIndex || fileSyncIndexes.length === 1) {
fileUp(callback);
return;
}
// Get document title/content
uploadContent = localStorage[fileIndex + ".content"];
uploadContentCRC = core.crc32(uploadContent);
uploadTitle = localStorage[fileIndex + ".title"];
uploadTitleCRC = core.crc32(uploadTitle);
// Parse the list of synchronized locations associated to the document
uploadFileSyncIndexList = fileSyncIndexes.split(";");
locationUp(callback);
}
// Used to upload document changes from local storage
var uploadCycle = false;
function syncUp(callback) {
if(uploadCycle === true) {
// New upload cycle
uploadCycle = false;
uploadFileIndexList = localStorage["file.list"].split(";");
fileUp(callback);
}
else {
callback();
}
}
// Used to download file changes from Google Drive
function syncDownGdrive(callback) {
if (synchronizer.useGoogleDrive === false) {
callback();
return;
}
var lastChangeId = parseInt(localStorage[SYNC_PROVIDER_GDRIVE
+ "lastChangeId"]);
googleHelper.checkUpdates(lastChangeId, function(changes, newChangeId) {
if (changes === undefined) {
callback("error");
return;
}
googleHelper.downloadContent(changes, function(changes) {
if (changes === undefined) {
callback("error");
return;
}
var updateFileTitles = false;
for ( var i = 0; i < changes.length; i++) {
var change = changes[i];
var fileSyncIndex = SYNC_PROVIDER_GDRIVE + change.fileId;
var fileIndex = fileManager.getFileIndexFromSync(fileSyncIndex);
// No file corresponding (file may have been deleted locally)
if(fileIndex === undefined) {
fileManager.removeSync(fileSyncIndex);
continue;
}
var localTitle = localStorage[fileIndex + ".title"];
// File deleted
if (change.deleted === true) {
fileManager.removeSync(fileSyncIndex);
updateFileTitles = true;
core.showMessage('"' + localTitle + '" has been removed from Google Drive.');
continue;
}
var localTitleChanged = localStorage[fileSyncIndex + ".titleCRC"] != core.crc32(localTitle);
var localContent = localStorage[fileIndex + ".content"];
var localContentChanged = localStorage[fileSyncIndex + ".contentCRC"] != core.crc32(localContent);
var file = change.file;
var fileTitleChanged = localTitle != file.title;
var fileContentChanged = localContent != file.content;
// Conflict detection
if ((fileTitleChanged === true && localTitleChanged === true)
|| (fileContentChanged === true && localContentChanged === true)) {
fileManager.createFile(localTitle + " (backup)", localContent);
updateFileTitles = true;
core.showMessage('Conflict detected on "' + localTitle + '". A backup has been created locally.');
}
// If file title changed
if(fileTitleChanged) {
localStorage[fileIndex + ".title"] = file.title;
updateFileTitles = true;
core.showMessage('"' + localTitle + '" has been renamed to "' + file.title + '" on Google Drive.');
}
// If file content changed
if(fileContentChanged) {
localStorage[fileIndex + ".content"] = file.content;
core.showMessage('"' + file.title + '" has been updated from Google Drive.');
if(fileIndex == localStorage["file.current"]) {
updateFileTitles = false; // Done by next function
fileManager.selectFile(); // Refresh editor
}
}
// Update file etag and CRCs
localStorage[fileSyncIndex + ".etag"] = file.etag;
localStorage[fileSyncIndex + ".contentCRC"] = core.crc32(file.content);
localStorage[fileSyncIndex + ".titleCRC"] = core.crc32(file.title);
}
if(updateFileTitles) {
fileManager.updateFileTitles();
}
localStorage[SYNC_PROVIDER_GDRIVE
+ "lastChangeId"] = newChangeId;
callback();
});
});
}
// Used to download file changes from Dropbox
function syncDownDropbox(callback) {
if (synchronizer.useDropbox === false) {
callback();
return;
}
var lastChangeId = localStorage[SYNC_PROVIDER_DROPBOX + "lastChangeId"];
dropboxHelper.checkUpdates(lastChangeId, function(changes, newChangeId) {
if (changes === undefined) {
callback("error");
return;
}
dropboxHelper.downloadContent(changes, function(changes) {
if (changes === undefined) {
callback("error");
return;
}
var updateFileTitles = false;
for ( var i = 0; i < changes.length; i++) {
var change = changes[i];
var fileSyncIndex = SYNC_PROVIDER_DROPBOX + encodeURIComponent(change.path.toLowerCase());
var fileIndex = fileManager.getFileIndexFromSync(fileSyncIndex);
// No file corresponding (file may have been deleted locally)
if(fileIndex === undefined) {
fileManager.removeSync(fileSyncIndex);
continue;
}
var localTitle = localStorage[fileIndex + ".title"];
// File deleted
if (change.wasRemoved === true) {
fileManager.removeSync(fileSyncIndex);
updateFileTitles = true;
core.showMessage('"' + localTitle + '" has been removed from Dropbox.');
continue;
}
var localContent = localStorage[fileIndex + ".content"];
var localContentChanged = localStorage[fileSyncIndex + ".contentCRC"] != core.crc32(localContent);
var file = change.stat;
var fileContentChanged = localContent != file.content;
// Conflict detection
if (fileContentChanged === true && localContentChanged === true) {
fileManager.createFile(localTitle + " (backup)", localContent);
updateFileTitles = true;
core.showMessage('Conflict detected on "' + localTitle + '". A backup has been created locally.');
}
// If file content changed
if(fileContentChanged) {
localStorage[fileIndex + ".content"] = file.content;
core.showMessage('"' + localTitle + '" has been updated from Dropbox.');
if(fileIndex == localStorage["file.current"]) {
updateFileTitles = false; // Done by next function
fileManager.selectFile(); // Refresh editor
}
}
// Update file version and CRC
localStorage[fileSyncIndex + ".version"] = file.versionTag;
localStorage[fileSyncIndex + ".contentCRC"] = core.crc32(file.content);
}
if(updateFileTitles) {
fileManager.updateFileTitles();
}
localStorage[SYNC_PROVIDER_DROPBOX
+ "lastChangeId"] = newChangeId;
callback();
});
});
}
function syncDown(callback) {
syncDownGdrive(function() {
syncDownDropbox(callback);
});
};
var syncRunning = false;
var lastSync = 0;
synchronizer.sync = function() {
// If sync is already running or timeout is not reached or offline
if (syncRunning || lastSync + SYNC_PERIOD > core.currentTime || core.isOffline) {
return;
}
syncRunning = true;
uploadCycle = true;
lastSync = core.currentTime;
synchronizer.updateSyncButton();
function isError(error) {
if(error !== undefined) {
syncRunning = false;
synchronizer.updateSyncButton();
return true;
}
return false;
}
syncDown(function(error) {
if(isError(error)) {
return;
}
syncUp(function(error) {
if(isError(error)) {
return;
}
syncRunning = false;
uploadPending = false;
});
});
};
synchronizer.init = function(coreModule, fileManagerModule) {
core = coreModule;
fileManager = fileManagerModule;
synchronizer.updateSyncButton();
$(".action-force-sync").click(function() {
if(!$(this).hasClass("disabled")) {
synchronizer.forceSync();
}
});
};
return synchronizer;
});