sample php ussd app

ussdAppSample.php

<?php
$ussdRequest = json_decode(@file_get_contents('php://input'));

$ussdResponse = new stdclass;

if ($ussdRequest != NULL)
switch ($ussdRequest->Type) {
	
	case 'Initiation':
		$ussdResponse->Message =
			"Welcome to Transbit\n \n" .
			"1. Pay Bills\n2. Enter Merchant Number\n3. List of Merchants";
		$ussdResponse->Type = 'Response';
	break;
	
	case 'Response':
		switch ($ussdRequest->Sequence) {

			case 2:
				$items = array('1' => 'Fixtures', '2' => 'Bet');
				if ($ussdRequest->Message == 1) {
    				 $ussdResponse->Message = 
    				 "Pay your Bills\n \n" .
    				 "1. DSTV\n2. GO TV\n3. ECG";
 					 $ussdResponse->Type = 'Response';					 
				} 
				else if ($ussdRequest->Message == 2) {
					$ussdResponse->Message =
						"Pay a Merchant\n \n" .
						"Enter Merchant Number:";
					$ussdResponse->Type = 'Response';
				}
				else if ($ussdRequest->Message == 3) {
					$ussdResponse->Message =
						"Select a Merchant\n \n" .
						"1. Shoprite\n2. Palace shopping mall \n3. Silverbird";
					$ussdResponse->Type = 'Response';
				}
			break;
			
			case 3:
				$ussdResponse->Message = "Enter Amount (GHc) ";
				$ussdResponse->Type = 'Response';
			break;

			case 4:	
				$ussdResponse->Message = 'Thank you for using Transbit.';
				$ussdResponse->Type = 'Release';
			break;			
			// Unexpected request. If the code here should ever
			// execute, it means the request is probably forged.
			default:
				$ussdResponse->Message = 'Unexpected request.';
				$ussdResponse->Type = 'Release';
				break;
		}
		break;
		
	// Session cleanup.
	// Not much to do here.
	default:
		$ussdResponse->Message = 'Duh.';
		$ussdResponse->Type = 'Release';
		break;
}
// An error has occured.
// Probably the request JSON could not be parsed.
else {
	$ussdResponse->Message = 'Invalid USSD request.';
	$ussdResponse->Type = 'Release';
}
// Let's set the HTTP content-type of our response, encode our
// USSD response object into JSON, and flush the output.
header('Content-type: application/json; charset=utf-8');
echo json_encode($ussdResponse);
?>