Smile.co.uk statements fixer - add balance per row and pending transactions amount.

smileStatementFixer.js

(function() {
	function strToAmount(str) {
		var parts = str.trim().match(/^£(\d+\.\d{2})(-)?/);
		if (!parts) return 0;
		return +(+parts[1] * (parts[2]?-1:1)).toFixed(2);
	}

	function amountToStr(amount) {
		amount = amount.toFixed(2);
		if (amount < 0) {
			amount = Math.abs(amount)+'-';
		};
		return '£'+amount;
	}

	function el(type,attrs,text) {
		var _el = document.createElement(type);
		if (attrs) for (var a in attrs) {
			_el.setAttribute(a,attrs[a]);
		};
		if (text) _el.appendChild(document.createTextNode(text));
		return _el;
	};

	function getBalance() {
		var balanceText = document.querySelector('.recentTransactionsAccountData table tr:nth-child(2) td:nth-child(2)').innerText;
		return strToAmount(balanceText);
	};

	function getAvailable() {
		var availableText = document.querySelector('.recentTransactionsAccountData table tr:nth-child(3) td:nth-child(2)').innerText;
		return strToAmount(availableText);
	};

	function getOverdraft() {
		var overdraftText = document.querySelector('.recentTransactionsAccountData table tr:nth-child(4) td:nth-child(2)').innerText;
		return strToAmount(overdraftText);
	};

	function insertBalanceHeader() {
		document.querySelector('.summaryTable thead tr th:nth-child(2)').width = '40%';
		document.querySelector('.summaryTable thead tr').appendChild(el('th',{'class':'summaryHeaderBoldRight',width:'15%'},'balance'));
	};

	function insertPendingTransactions() {
		var pending = +(getBalance()-(getAvailable()-getOverdraft())).toFixed(2);
		elRow = el('tr');
		elRow.appendChild(el('td',{},'Pending transactions'));
		elRow.appendChild(el('td',{'class':'pinkText leftPadded'},'£'+pending.toFixed(2)));
		elRow.appendChild(el('td'));
		document.querySelector('.recentTransactionsAccountData table tbody').appendChild(elRow);
	};

	function insertBalanceRows() {
		var balance = getBalance();
		var rows = document.querySelectorAll('.summaryTable tbody tr:not(:last-child)');
		rows = Array.prototype.slice.call(rows,rows);
		rows.forEach(function(row) {
			var credit = strToAmount(row.children[2].innerText);
			var debit = strToAmount(row.children[3].innerText);
			row.appendChild(el('td',{class:'summaryDetailR'},amountToStr(balance)));
			balance = balance - credit + debit;
		});
	};

	if (document.location.host == "banking.smile.co.uk" && (document.location.pathname=="/SmileWeb2/balances.do" || document.location.pathname=="/SmileWeb2/prepareDomesticRecentItems.do")) {
		insertBalanceHeader();
		insertBalanceRows();
		insertPendingTransactions();
	};
})();