var TransactionDatabase = function () {
	this.txs = [];
	this.txIndex = {};
};

EventEmitter.augment(TransactionDatabase.prototype);

TransactionDatabase.prototype.addTransaction = function (tx) {
	this.addTransactionNoUpdate(tx);
	$(this).trigger('update');
};

TransactionDatabase.prototype.addTransactionNoUpdate = function (tx) {
	// Return if transaction is already known
	if (this.txIndex[tx.hash]) {
		return;
	}

	this.txs.push(new Bitcoin.Transaction(tx));
	this.txIndex[tx.hash] = tx;
};

TransactionDatabase.prototype.removeTransaction = function (hash) {
	this.removeTransactionNoUpdate(hash);
	$(this).trigger('update');
};

TransactionDatabase.prototype.removeTransactionNoUpdate = function (hash) {
	var tx = this.txIndex[hash];

	if (!tx) {
		// If the tx is not in the index, we don't actually waste our
		// time looping through the array.
		return;
	}

	for (var i = 0, l = this.txs.length; i < l; i++) {
		if (this.txs[i].hash == hash) {
			this.txs.splice(i, 1);
			break;
		}
	}

	delete this.txIndex[hash];
};

TransactionDatabase.prototype.loadTransactions = function (txs) {
	for (var i = 0; i < txs.length; i++) {
		this.addTransactionNoUpdate(txs[i]);
	}
	$(this).trigger('update');
};

TransactionDatabase.prototype.getTransactions = function () {
	return this.txs;
};