All: Started moving sync glue logic to SyncTarget classes

ReactNativeClient/lib/BaseSyncTarget.js

@@ -0,0 +1,82 @@
+const { reg } = require('lib/registry.js');
+
+class BaseSyncTarget {
+
+	constructor(db) {
+		this.db_ = db;
+		this.synchronizer_ = null;
+		this.initState_ = null;
+		this.logger_ = null;
+	}
+
+	logger() {
+		return this.logger_;
+	}
+
+	setLogger(v) {
+		this.logger_ = v;
+	}
+
+	db() {
+		return this.db_;
+	}
+
+	isAuthenticated() {
+		return false;
+	}
+
+	name() {
+		throw new Error('Not implemented');
+	}
+
+	label() {
+		throw new Error('Not implemented');
+	}
+
+	async initSynchronizer() {
+		throw new Error('Not implemented');
+	}
+
+	async synchronizer() {
+		if (this.synchronizer_) return this.synchronizer_;
+
+		if (this.initState_ == 'started') {
+			// Synchronizer is already being initialized, so wait here till it's done.
+			return new Promise((resolve, reject) => {
+				const iid = setInterval(() => {
+					if (this.initState_ == 'ready') {
+						clearInterval(iid);
+						resolve(this.synchronizer_);
+					}
+					if (this.initState_ == 'error') {
+						clearInterval(iid);
+						reject(new Error('Could not initialise synchroniser'));
+					}
+				}, 1000);
+			});
+		} else {
+			this.initState_ = 'started';
+
+			try {
+				this.synchronizer_ = await this.initSynchronizer();
+				this.synchronizer_.setLogger(this.logger());
+				this.synchronizer_.dispatch = BaseSyncTarget.dispatch;
+				this.initState_ = 'ready';
+				return this.synchronizer_;
+			} catch (error) {
+				this.initState_ = 'error';
+				throw error;
+			}
+		}
+	}
+
+	async syncStarted() {
+		if (!this.synchronizer_) return false;
+		if (!this.isAuthenticated()) return false;
+		const sync = await this.synchronizer();
+		return sync.state() != 'idle';
+	}
+
+}
+
+module.exports = BaseSyncTarget;