<?php

/*
	This file is part of Blockchain.info WHMCS Payment Gateway.
	
	Created by Alexander "Doctor McKay" Corn (http://www.doctormckay.com/)
	
	Contributions by	Ricky Burgin (http://ricky.burg.in/)
	
	
	Code repository: https://bitbucket.org/Doctor_McKay/blockchain.info-whmcs-payment-gateway
	
    Blockchain.info WHMCS Payment Gateway is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.
	
    Blockchain.info WHMCS Payment Gateway is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.
	
    You should have received a copy of the GNU General Public License
    along with Blockchain.info WHMCS Payment Gateway.  If not, see <http://www.gnu.org/licenses/>.
	
	WHMCS and Blockchain are not affiliated with this project in any manner.
*/

function blockchain_config() {
	return array(
		"FriendlyName" => array("Type" => "System", "Value" => "Blockchain.info"),
		"receiving_address" => array("FriendlyName" => "Bitcoin Address", "Type" => "text", "Size" => "64", "Description" => "Bitcoin address where received payments will be sent"),
		"shared_wallet" => array("FriendlyName" => "Shared Wallet", "Type" => "yesno", "Description" => "Tick to send payments through a shared wallet, anonymising them. Transactions will take slightly longer to confirm. 0.5% fee."),
		"confirmations_required" => array("FriendlyName" => "Confirmations Required", "Type" => "text", "Size" => "4", "Description" => "Number of confirmations required before an invoice is marked 'Paid'. Has no effect if 'Shared Wallet' is ticked above."),
	);
}

function blockchain_link($params) {
	mysql_query("CREATE TABLE IF NOT EXISTS `blockchain_payments` (`invoice_id` int(11) NOT NULL, `amount` float(11,8) NOT NULL, `address` varchar(64) NOT NULL, `secret` varchar(64) NOT NULL, `confirmations` int(11) NOT NULL, `status` enum('unpaid','confirming','paid') NOT NULL, PRIMARY KEY (`invoice_id`))");
	
	$q = mysql_fetch_array(mysql_query("SELECT * FROM `blockchain_payments` WHERE invoice_id = '{$params['invoiceid']}'"));
	if($q['address']) {
		$amount = $q['amount'];
		$address = $q['address'];
		$confirmations = $q['confirmations'];
	}
	
	$ch = curl_init();
	curl_setopt($ch, CURLOPT_URL, "http://blockchain.info/tobtc?currency={$params['currency']}&value={$params['amount']}");
	curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
	$amount = curl_exec($ch);
	$status = curl_getinfo($ch, CURLINFO_HTTP_CODE);
	curl_close($ch);
	
	if($status >= 300 || $amount < 0.0005) { // Blockchain.info will only relay a transaction if it's 0.0005 BTC or larger
		return "Transaction amount too low. Please try another payment method or open a ticket with Billing.";
	}
	
	$shared = 'false';
	if($params['shared_wallet'] == 'on') {
		$shared = 'true';
	}
	
	$secret = '';
	$characters = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890';
	for($i = 0; $i < 64; $i++) {
		$secret .= substr($characters, rand(0, strlen($characters) - 1), 1);
	}
	
	$callback_url = urlencode($params['systemurl'] . "/modules/gateways/callback/blockchain.php?secret=$secret");
	
	$ch = curl_init();
	curl_setopt($ch, CURLOPT_URL, "https://blockchain.info/api/receive?method=create&address={$params['receiving_address']}&callback=$callback_url");
	curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
	curl_setopt($ch, CURLOPT_CAINFO, "./modules/gateways/blockchain/comodo-essentialssl-ca-bundle.crt"); // Use Comodo's certificate bundle as Blockchain changed their CA recently which broke curl HTTPS usage. May want to code in an attempt to try the default system CA bundle first, then fall back to this certificate if it fails - just in case Blockchain switch their CA again.
	$response = curl_exec($ch);
	$status = curl_getinfo($ch, CURLINFO_HTTP_CODE);
	curl_close($ch);
	
	if($status >= 300) {
		return "An error has occurred, please contact Billing or choose a different payment method. (Error ID: 1)";
	}
	
	$response = json_decode($response);
	if(!$response->input_address) {
		return "An error has occurred, please contact Billing or choose a different payment method. (Error ID: 2)";
	}
	
	mysql_query("INSERT INTO `blockchain_payments` SET invoice_id = '{$params['invoiceid']}', amount = '" . mysql_real_escape_string($amount) . "', address = '" . mysql_real_escape_string($response->input_address) . "', secret = '$secret', confirmations = '0', status = 'unpaid'");
	
	return "<iframe src='{$params['systemurl']}/modules/gateways/blockchain.php?invoice={$params['invoiceid']}' style='border:none; height:400px'>Your browser does not support frames.</iframe>";
}

if($_GET['invoice']) {
require('./../../dbconnect.php');
include("./../../includes/gatewayfunctions.php");
$gateway = getGatewayVariables('blockchain');
?>
<!doctype html>
<html>
	<head>
		<title>Blockchain.info Invoice Payment</title>
		<script src="//ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js"></script>
		<script src="blockchain/jquery.qrcode.min.js"></script>
                <script src="blockchain/qrcode.js"></script>
		<script type="text/javascript">
		function checkStatus() {
			$.get("blockchain.php?checkinvoice=<?php echo $_GET['invoice']; ?>", function(data) {
				if(data == 'paid') {
					parent.location.href = '<?php echo $gateway['systemurl']; ?>/viewinvoice.php?id=<?php echo $_GET['invoice']; ?>';
				} else if(data == 'unpaid') {
					setTimeout(checkStatus, 5000);
				} else {
					$("#content").html("Transaction confirming... " + data + "/<?php echo $gateway['confirmations_required']; ?> confirmations");
					setTimeout(checkStatus, 10000);
				}
			});
		}
		</script>
		<style>
		body {
			font-family:Tahoma;
			font-size:12px;
			text-align:center;
		}
		a:link, a:visited {
			color:#08c;
			text-decoration:none;
		}
		a:hover {
			color:#005580;
			text-decoration:underline
		}
		</style>
	</head>
	<body onload="checkStatus()">
		<p id="content"><center><div id="qrcodeCanvas"></div></center><br><br><?php echo blockchain_get_frame(); ?></p>
	</body>
</html>
<?php
}

function blockchain_get_frame() {
	global $gateway;
	
	$q = mysql_fetch_array(mysql_query("SELECT * FROM `blockchain_payments` WHERE invoice_id = '" . mysql_real_escape_string($_GET['invoice']) . "'"));
	if(!$q['address']) {
		return "An error has occurred, please contact Billing or choose a different payment method. (Error ID: 3)";
	}

	// QR code string for BTC wallet apps
	$qr_string = "bitcoin:{$q['address']}?amount={$q['amount']}&label=" . urlencode($gateway['companyname'] . ' Invoice #' . $q['invoice_id']);	
	
	return "<script>jQuery('#qrcodeCanvas').qrcode({ text : '{$qr_string}'});</script>Please send <b><a href='bitcoin:{$q['address']}?amount={$q['amount']}&label=" . urlencode($gateway['companyname'] . ' Invoice #' . $q['invoice_id']) . "'>{$q['amount']} BTC</a></b> to address:<br /><br /><b><a href='https://blockchain.info/address/{$q['address']}' target='_blank'>{$q['address']}</a></b><br /><br /><img src='" . $gateway['systemurl'] . "/images/loading.gif' />";
}

if($_GET['checkinvoice']) {
	header('Content-type: text/plain');
	require('./../../dbconnect.php');
	$q = mysql_fetch_array(mysql_query("SELECT * FROM `blockchain_payments` WHERE invoice_id = '" . mysql_real_escape_string($_GET['checkinvoice']) . "'"));
	
	if($q['status'] == 'paid') {
		echo 'paid';
	} elseif($q['status'] == 'confirming') {
		echo $q['confirmations'];
	} else {
		echo 'unpaid';
	}
}

?>