michael@0: /* -*- Mode: js2; js2-basic-offset: 2; indent-tabs-mode: nil; -*- */
michael@0: /* vim: set ft=javascript ts=2 et sw=2 tw=80: */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: 'use strict'
michael@0: 
michael@0: this.EXPORTED_SYMBOLS = ["DataStore"];
michael@0: 
michael@0: function debug(s) {
michael@0:   //dump('DEBUG DataStore: ' + s + '\n');
michael@0: }
michael@0: 
michael@0: const {classes: Cc, interfaces: Ci, utils: Cu, results: Cr} = Components;
michael@0: 
michael@0: const REVISION_ADDED = "added";
michael@0: const REVISION_UPDATED = "updated";
michael@0: const REVISION_REMOVED = "removed";
michael@0: const REVISION_VOID = "void";
michael@0: 
michael@0: // This value has to be tuned a bit. Currently it's just a guess
michael@0: // and yet we don't know if it's too low or too high.
michael@0: const MAX_REQUESTS = 25;
michael@0: 
michael@0: Cu.import("resource://gre/modules/DataStoreCursorImpl.jsm");
michael@0: Cu.import("resource://gre/modules/DataStoreDB.jsm");
michael@0: Cu.import('resource://gre/modules/Services.jsm');
michael@0: Cu.import('resource://gre/modules/XPCOMUtils.jsm');
michael@0: Cu.importGlobalProperties(["indexedDB"]);
michael@0: 
michael@0: XPCOMUtils.defineLazyServiceGetter(this, "cpmm",
michael@0:                                    "@mozilla.org/childprocessmessagemanager;1",
michael@0:                                    "nsIMessageSender");
michael@0: 
michael@0: /* Helper functions */
michael@0: function createDOMError(aWindow, aEvent) {
michael@0:   return new aWindow.DOMError(aEvent);
michael@0: }
michael@0: 
michael@0: function throwInvalidArg(aWindow) {
michael@0:   return aWindow.Promise.reject(
michael@0:     new aWindow.DOMError("SyntaxError", "Non-numeric or invalid id"));
michael@0: }
michael@0: 
michael@0: function throwReadOnly(aWindow) {
michael@0:   return aWindow.Promise.reject(
michael@0:     new aWindow.DOMError("ReadOnlyError", "DataStore in readonly mode"));
michael@0: }
michael@0: 
michael@0: function validateId(aId) {
michael@0:   // If string, it cannot be empty.
michael@0:   if (typeof(aId) == 'string') {
michael@0:     return aId.length;
michael@0:   }
michael@0: 
michael@0:   aId = parseInt(aId);
michael@0:   return (!isNaN(aId) && aId > 0);
michael@0: }
michael@0: 
michael@0: /* DataStore object */
michael@0: this.DataStore = function(aWindow, aName, aOwner, aReadOnly) {
michael@0:   debug("DataStore created");
michael@0:   this.init(aWindow, aName, aOwner, aReadOnly);
michael@0: }
michael@0: 
michael@0: this.DataStore.prototype = {
michael@0:   classDescription: "DataStore XPCOM Component",
michael@0:   classID: Components.ID("{db5c9602-030f-4bff-a3de-881a8de370f2}"),
michael@0:   contractID: "@mozilla.org/dom/datastore-impl;1",
michael@0:   QueryInterface: XPCOMUtils.generateQI([Components.interfaces.nsISupports,
michael@0:                                          Components.interfaces.nsIObserver]),
michael@0: 
michael@0:   callbacks: [],
michael@0: 
michael@0:   _window: null,
michael@0:   _name: null,
michael@0:   _owner: null,
michael@0:   _readOnly: null,
michael@0:   _revisionId: null,
michael@0:   _exposedObject: null,
michael@0:   _cursor: null,
michael@0:   _shuttingdown: false,
michael@0:   _eventTarget: null,
michael@0: 
michael@0:   init: function(aWindow, aName, aOwner, aReadOnly) {
michael@0:     debug("DataStore init");
michael@0: 
michael@0:     this._window = aWindow;
michael@0:     this._name = aName;
michael@0:     this._owner = aOwner;
michael@0:     this._readOnly = aReadOnly;
michael@0: 
michael@0:     this._db = new DataStoreDB();
michael@0:     this._db.init(aOwner, aName);
michael@0: 
michael@0:     Services.obs.addObserver(this, "inner-window-destroyed", false);
michael@0: 
michael@0:     let util = aWindow.QueryInterface(Ci.nsIInterfaceRequestor)
michael@0:                       .getInterface(Ci.nsIDOMWindowUtils);
michael@0:     this._innerWindowID = util.currentInnerWindowID;
michael@0: 
michael@0:     cpmm.addMessageListener("DataStore:Changed:Return:OK", this);
michael@0:     cpmm.sendAsyncMessage("DataStore:RegisterForMessages",
michael@0:                           { store: this._name, owner: this._owner });
michael@0:   },
michael@0: 
michael@0:   observe: function(aSubject, aTopic, aData) {
michael@0:     let wId = aSubject.QueryInterface(Ci.nsISupportsPRUint64).data;
michael@0:     if (wId == this._innerWindowID) {
michael@0:       Services.obs.removeObserver(this, "inner-window-destroyed");
michael@0: 
michael@0:       cpmm.removeMessageListener("DataStore:Changed:Return:OK", this);
michael@0:       cpmm.sendAsyncMessage("DataStore:UnregisterForMessages");
michael@0:       this._shuttingdown = true;
michael@0:       this._db.close();
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   setEventTarget: function(aEventTarget) {
michael@0:     this._eventTarget = aEventTarget;
michael@0:   },
michael@0: 
michael@0:   newDBPromise: function(aTxnType, aFunction) {
michael@0:     let self = this;
michael@0:     return new this._window.Promise(function(aResolve, aReject) {
michael@0:       debug("DBPromise started");
michael@0:       self._db.txn(
michael@0:         aTxnType,
michael@0:         function(aTxn, aStore, aRevisionStore) {
michael@0:           debug("DBPromise success");
michael@0:           aFunction(aResolve, aReject, aTxn, aStore, aRevisionStore);
michael@0:         },
michael@0:         function(aEvent) {
michael@0:           debug("DBPromise error");
michael@0:           aReject(createDOMError(self._window, aEvent));
michael@0:         }
michael@0:       );
michael@0:     });
michael@0:   },
michael@0: 
michael@0:   checkRevision: function(aReject, aRevisionStore, aRevisionId, aCallback) {
michael@0:     if (!aRevisionId) {
michael@0:       aCallback();
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     let self = this;
michael@0: 
michael@0:     let request = aRevisionStore.openCursor(null, 'prev');
michael@0:     request.onsuccess = function(aEvent) {
michael@0:       let cursor = aEvent.target.result;
michael@0:       if (!cursor) {
michael@0:         dump("This cannot really happen.");
michael@0:         return;
michael@0:       }
michael@0: 
michael@0:       if (cursor.value.revisionId != aRevisionId) {
michael@0:         aReject(new self._window.DOMError("ConstraintError",
michael@0:                                           "RevisionId is not up-to-date"));
michael@0:         return;
michael@0:       }
michael@0: 
michael@0:       aCallback();
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   getInternal: function(aStore, aIds, aCallback) {
michael@0:     debug("GetInternal: " + aIds.toSource());
michael@0: 
michael@0:     // Creation of the results array.
michael@0:     let results = new Array(aIds.length);
michael@0: 
michael@0:     // We're going to create this amount of requests.
michael@0:     let pendingIds = aIds.length;
michael@0:     let indexPos = 0;
michael@0: 
michael@0:     let self = this;
michael@0: 
michael@0:     function getInternalSuccess(aEvent, aPos) {
michael@0:       debug("GetInternal success. Record: " + aEvent.target.result);
michael@0:       results[aPos] = Cu.cloneInto(aEvent.target.result, self._window);
michael@0:       if (!--pendingIds) {
michael@0:         aCallback(results);
michael@0:         return;
michael@0:       }
michael@0: 
michael@0:       if (indexPos < aIds.length) {
michael@0:         // Just MAX_REQUESTS requests at the same time.
michael@0:         let count = 0;
michael@0:         while (indexPos < aIds.length && ++count < MAX_REQUESTS) {
michael@0:           getInternalRequest();
michael@0:         }
michael@0:       }
michael@0:     }
michael@0: 
michael@0:     function getInternalRequest() {
michael@0:       let currentPos = indexPos++;
michael@0:       let request = aStore.get(aIds[currentPos]);
michael@0:       request.onsuccess = function(aEvent) {
michael@0:         getInternalSuccess(aEvent, currentPos);
michael@0:       }
michael@0:     }
michael@0: 
michael@0:     getInternalRequest();
michael@0:   },
michael@0: 
michael@0:   putInternal: function(aResolve, aStore, aRevisionStore, aObj, aId) {
michael@0:     debug("putInternal " + aId);
michael@0: 
michael@0:     let self = this;
michael@0:     let request = aStore.put(aObj, aId);
michael@0:     request.onsuccess = function(aEvent) {
michael@0:       debug("putInternal success");
michael@0: 
michael@0:       self.addRevision(aRevisionStore, aId, REVISION_UPDATED,
michael@0:         function() {
michael@0:           debug("putInternal - revisionId increased");
michael@0:           // No wrap here because the result is always a int.
michael@0:           aResolve(aEvent.target.result);
michael@0:         }
michael@0:       );
michael@0:     };
michael@0:   },
michael@0: 
michael@0:   addInternal: function(aResolve, aStore, aRevisionStore, aObj, aId) {
michael@0:     debug("AddInternal");
michael@0: 
michael@0:     let self = this;
michael@0:     let request = aStore.add(aObj, aId);
michael@0:     request.onsuccess = function(aEvent) {
michael@0:       debug("Request successful. Id: " + aEvent.target.result);
michael@0:       self.addRevision(aRevisionStore, aEvent.target.result, REVISION_ADDED,
michael@0:         function() {
michael@0:           debug("AddInternal - revisionId increased");
michael@0:           // No wrap here because the result is always a int.
michael@0:           aResolve(aEvent.target.result);
michael@0:         }
michael@0:       );
michael@0:     };
michael@0:   },
michael@0: 
michael@0:   removeInternal: function(aResolve, aStore, aRevisionStore, aId) {
michael@0:     debug("RemoveInternal");
michael@0: 
michael@0:     let self = this;
michael@0:     let request = aStore.get(aId);
michael@0:     request.onsuccess = function(aEvent) {
michael@0:       debug("RemoveInternal success. Record: " + aEvent.target.result);
michael@0:       if (aEvent.target.result === undefined) {
michael@0:         aResolve(false);
michael@0:         return;
michael@0:       }
michael@0: 
michael@0:       let deleteRequest = aStore.delete(aId);
michael@0:       deleteRequest.onsuccess = function() {
michael@0:         debug("RemoveInternal success");
michael@0:         self.addRevision(aRevisionStore, aId, REVISION_REMOVED,
michael@0:           function() {
michael@0:             aResolve(true);
michael@0:           }
michael@0:         );
michael@0:       };
michael@0:     };
michael@0:   },
michael@0: 
michael@0:   clearInternal: function(aResolve, aStore, aRevisionStore) {
michael@0:     debug("ClearInternal");
michael@0: 
michael@0:     let self = this;
michael@0:     let request = aStore.clear();
michael@0:     request.onsuccess = function() {
michael@0:       debug("ClearInternal success");
michael@0:       self._db.clearRevisions(aRevisionStore,
michael@0:         function() {
michael@0:           debug("Revisions cleared");
michael@0: 
michael@0:           self.addRevision(aRevisionStore, 0, REVISION_VOID,
michael@0:             function() {
michael@0:               debug("ClearInternal - revisionId increased");
michael@0:               aResolve();
michael@0:             }
michael@0:           );
michael@0:         }
michael@0:       );
michael@0:     };
michael@0:   },
michael@0: 
michael@0:   getLengthInternal: function(aResolve, aStore) {
michael@0:     debug("GetLengthInternal");
michael@0: 
michael@0:     let request = aStore.count();
michael@0:     request.onsuccess = function(aEvent) {
michael@0:       debug("GetLengthInternal success: " + aEvent.target.result);
michael@0:       // No wrap here because the result is always a int.
michael@0:       aResolve(aEvent.target.result);
michael@0:     };
michael@0:   },
michael@0: 
michael@0:   addRevision: function(aRevisionStore, aId, aType, aSuccessCb) {
michael@0:     let self = this;
michael@0:     this._db.addRevision(aRevisionStore, aId, aType,
michael@0:       function(aRevisionId) {
michael@0:         self._revisionId = aRevisionId;
michael@0:         self.sendNotification(aId, aType, aRevisionId);
michael@0:         aSuccessCb();
michael@0:       }
michael@0:     );
michael@0:   },
michael@0: 
michael@0:   retrieveRevisionId: function(aSuccessCb) {
michael@0:     let self = this;
michael@0:     this._db.revisionTxn(
michael@0:       'readonly',
michael@0:       function(aTxn, aRevisionStore) {
michael@0:         debug("RetrieveRevisionId transaction success");
michael@0: 
michael@0:         let request = aRevisionStore.openCursor(null, 'prev');
michael@0:         request.onsuccess = function(aEvent) {
michael@0:           let cursor = aEvent.target.result;
michael@0:           if (cursor) {
michael@0:             self._revisionId = cursor.value.revisionId;
michael@0:           }
michael@0: 
michael@0:           aSuccessCb(self._revisionId);
michael@0:         };
michael@0:       }
michael@0:     );
michael@0:   },
michael@0: 
michael@0:   sendNotification: function(aId, aOperation, aRevisionId) {
michael@0:     debug("SendNotification");
michael@0:     if (aOperation == REVISION_VOID) {
michael@0:       aOperation = "cleared";
michael@0:     }
michael@0: 
michael@0:     cpmm.sendAsyncMessage("DataStore:Changed",
michael@0:                           { store: this.name, owner: this._owner,
michael@0:                             message: { revisionId: aRevisionId, id: aId,
michael@0:                                        operation: aOperation, owner: this._owner } } );
michael@0:   },
michael@0: 
michael@0:   receiveMessage: function(aMessage) {
michael@0:     debug("receiveMessage");
michael@0: 
michael@0:     if (aMessage.name != "DataStore:Changed:Return:OK") {
michael@0:       debug("Wrong message: " + aMessage.name);
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     // If this message is not for this DataStore, let's ignore it.
michael@0:     if (aMessage.data.owner != this._owner ||
michael@0:         aMessage.data.store != this._name) {
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     let self = this;
michael@0: 
michael@0:     this.retrieveRevisionId(
michael@0:       function() {
michael@0:         // If the window has been destroyed we don't emit the events.
michael@0:         if (self._shuttingdown) {
michael@0:           return;
michael@0:         }
michael@0: 
michael@0:         // If we have an active cursor we don't emit events.
michael@0:         if (self._cursor) {
michael@0:           return;
michael@0:         }
michael@0: 
michael@0:         let event = new self._window.DataStoreChangeEvent('change',
michael@0:                                                           aMessage.data.message);
michael@0:         self._eventTarget.dispatchEvent(event);
michael@0:       }
michael@0:     );
michael@0:   },
michael@0: 
michael@0:   get exposedObject() {
michael@0:     debug("get exposedObject");
michael@0:     return this._exposedObject;
michael@0:   },
michael@0: 
michael@0:   set exposedObject(aObject) {
michael@0:     debug("set exposedObject");
michael@0:     this._exposedObject = aObject;
michael@0:   },
michael@0: 
michael@0:   syncTerminated: function(aCursor) {
michael@0:     // This checks is to avoid that an invalid cursor stops a sync.
michael@0:     if (this._cursor == aCursor) {
michael@0:       this._cursor = null;
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   // Public interface :
michael@0: 
michael@0:   get name() {
michael@0:     return this._name;
michael@0:   },
michael@0: 
michael@0:   get owner() {
michael@0:     return this._owner;
michael@0:   },
michael@0: 
michael@0:   get readOnly() {
michael@0:     return this._readOnly;
michael@0:   },
michael@0: 
michael@0:   get: function() {
michael@0:     let ids = Array.prototype.slice.call(arguments);
michael@0:     for (let i = 0; i < ids.length; ++i) {
michael@0:       if (!validateId(ids[i])) {
michael@0:         return throwInvalidArg(this._window);
michael@0:       }
michael@0:     }
michael@0: 
michael@0:     let self = this;
michael@0: 
michael@0:     // Promise<Object>
michael@0:     return this.newDBPromise("readonly",
michael@0:       function(aResolve, aReject, aTxn, aStore, aRevisionStore) {
michael@0:                self.getInternal(aStore, ids,
michael@0:                                 function(aResults) {
michael@0:           aResolve(ids.length > 1 ? aResults : aResults[0]);
michael@0:         });
michael@0:       }
michael@0:     );
michael@0:   },
michael@0: 
michael@0:   put: function(aObj, aId, aRevisionId) {
michael@0:     if (!validateId(aId)) {
michael@0:       return throwInvalidArg(this._window);
michael@0:     }
michael@0: 
michael@0:     if (this._readOnly) {
michael@0:       return throwReadOnly(this._window);
michael@0:     }
michael@0: 
michael@0:     let self = this;
michael@0: 
michael@0:     // Promise<void>
michael@0:     return this.newDBPromise("readwrite",
michael@0:       function(aResolve, aReject, aTxn, aStore, aRevisionStore) {
michael@0:         self.checkRevision(aReject, aRevisionStore, aRevisionId, function() {
michael@0:           self.putInternal(aResolve, aStore, aRevisionStore, aObj, aId);
michael@0:         });
michael@0:       }
michael@0:     );
michael@0:   },
michael@0: 
michael@0:   add: function(aObj, aId, aRevisionId) {
michael@0:     if (aId) {
michael@0:       if (!validateId(aId)) {
michael@0:         return throwInvalidArg(this._window);
michael@0:       }
michael@0:     }
michael@0: 
michael@0:     if (this._readOnly) {
michael@0:       return throwReadOnly(this._window);
michael@0:     }
michael@0: 
michael@0:     let self = this;
michael@0: 
michael@0:     // Promise<int>
michael@0:     return this.newDBPromise("readwrite",
michael@0:       function(aResolve, aReject, aTxn, aStore, aRevisionStore) {
michael@0:         self.checkRevision(aReject, aRevisionStore, aRevisionId, function() {
michael@0:           self.addInternal(aResolve, aStore, aRevisionStore, aObj, aId);
michael@0:         });
michael@0:       }
michael@0:     );
michael@0:   },
michael@0: 
michael@0:   remove: function(aId, aRevisionId) {
michael@0:     if (!validateId(aId)) {
michael@0:       return throwInvalidArg(this._window);
michael@0:     }
michael@0: 
michael@0:     if (this._readOnly) {
michael@0:       return throwReadOnly(this._window);
michael@0:     }
michael@0: 
michael@0:     let self = this;
michael@0: 
michael@0:     // Promise<void>
michael@0:     return this.newDBPromise("readwrite",
michael@0:       function(aResolve, aReject, aTxn, aStore, aRevisionStore) {
michael@0:         self.checkRevision(aReject, aRevisionStore, aRevisionId, function() {
michael@0:           self.removeInternal(aResolve, aStore, aRevisionStore, aId);
michael@0:         });
michael@0:       }
michael@0:     );
michael@0:   },
michael@0: 
michael@0:   clear: function(aRevisionId) {
michael@0:     if (this._readOnly) {
michael@0:       return throwReadOnly(this._window);
michael@0:     }
michael@0: 
michael@0:     let self = this;
michael@0: 
michael@0:     // Promise<void>
michael@0:     return this.newDBPromise("readwrite",
michael@0:       function(aResolve, aReject, aTxn, aStore, aRevisionStore) {
michael@0:         self.checkRevision(aReject, aRevisionStore, aRevisionId, function() {
michael@0:           self.clearInternal(aResolve, aStore, aRevisionStore);
michael@0:         });
michael@0:       }
michael@0:     );
michael@0:   },
michael@0: 
michael@0:   get revisionId() {
michael@0:     return this._revisionId;
michael@0:   },
michael@0: 
michael@0:   getLength: function() {
michael@0:     let self = this;
michael@0: 
michael@0:     // Promise<int>
michael@0:     return this.newDBPromise("readonly",
michael@0:       function(aResolve, aReject, aTxn, aStore, aRevisionStore) {
michael@0:         self.getLengthInternal(aResolve, aStore);
michael@0:       }
michael@0:     );
michael@0:   },
michael@0: 
michael@0:   sync: function(aRevisionId) {
michael@0:     debug("Sync");
michael@0:     this._cursor = new DataStoreCursor(this._window, this, aRevisionId);
michael@0: 
michael@0:     let cursorImpl = this._window.DataStoreCursorImpl.
michael@0:                                   _create(this._window, this._cursor);
michael@0: 
michael@0:     let exposedCursor = new this._window.DataStoreCursor();
michael@0:     exposedCursor.setDataStoreCursorImpl(cursorImpl);
michael@0:     return exposedCursor;
michael@0:   }
michael@0: };