<?php
if ($_SERVER['REQUEST_METHOD'] != 'POST') {
    echo 'This script is not supposed to be viewed in a browser!';
    exit;
}

$con = new mysqli('localhost', 'username', '', 'my_db');

$insert_sms_success = FALSE;

if (mysqli_connect_errno() == 0) {

    $sent_dt       = $_POST['time'];
    $txt           = $_POST['content'];
    $txt           = mysqli_real_escape_string($con, $txt);
    $sender_number = mysqli_real_escape_string($con, $sender_number);

    $sql = "INSERT INTO SMS_IN(sms_text,sent_dt) VALUES ('$txt','$sent_dt')";

    $insert_sms_success = mysqli_query($con, $sql);
    mysqli_close($con);
}

if ($insert_sms_success) {
} else {
    http_response_code(500);
}
?>

function get_message()
{
$error = NULL;
// Set success to false as the default success status
$success = false;
/**
 *  Get the phone number that sent the SMS.
 */
if (isset($_POST['from']))
{
    $from = $_POST['from'];
}
else
{
    $error = 'The from variable was not set';
}
/**
 * Get the SMS aka the message sent.
 */
if (isset($_POST['message']))
{
    $message = $_POST['message'];
}
else
{
    $error = 'The message variable was not set';
}
/**
 * Get the secret key set on SMSsync side
 * for matching on the server side.
 */
if (isset($_POST['secret']))
{
    $secret = $_POST['secret'];
}
/**
 * Get the timestamp of the SMS
 */
if(isset($_POST['sent_timestamp']))
{
    $sent_timestamp = $_POST['sent_timestamp'];
}
/**
 * Get the phone number of the device SMSsync is
 * installed on.
 */
if (isset($_POST['sent_to']))
{
    $sent_to = $_POST['sent_to'];
}
/**
 * Get the unique message id
 */
if (isset($_POST['message_id']))
{
    $message_id = $_POST['message_id'];
}
/**
 * Get device ID
 */
if (isset($_POST['device_id']))
{
    $device_id = $_POST['device_id'];
}
/**
 * Now we have retrieved the data sent over by SMSsync
 * via HTTP. Next thing to do is to do something with
 * the data. Either echo it or write it to a file or even
 * store it in a database. This is entirely up to you.
 * After, return a JSON string back to SMSsync to know
 * if the web service received the message successfully or not.
 *
 * In this demo, we are just going to save the data
 * received into a text file.
 *
 */
if ((strlen($from) > 0) AND (strlen($message) > 0) AND
    (strlen($sent_timestamp) > 0 )
    AND (strlen($message_id) > 0))
{
    /* The screte key set here is 123456. Make sure you enter
     * that on SMSsync.
     */
    if ( ( $secret == '123456'))
    {
        $success = true;
    } else
    {
        $error = "The secret value sent from the device does not match the one on the server";
    }
    // now let's write the info sent by SMSsync
    //to a file called test.txt
    $string = "From: ".$from."n";
    $string .= "Message: ".$message."n";
    $string .= "Timestamp: ".$sent_timestamp."n";
    $string .= "Messages Id:" .$message_id."n";
    $string .= "Sent to: ".$sent_to."n";
    $string .= "Device ID: ".$device_id."nnn";
    write_message_to_file($string);
}
/**
 * Comment the code below out if you want to send an instant
 * reply as SMS to the user.
 *
 * This feature requires the "Get reply from server" checked on SMSsync.
 */
 send_instant_message($from);
/**
  * Now send a JSON formatted string to SMSsync to
  * acknowledge that the web service received the message
  */
 $response = json_encode([
    "payload"=> [
        "success"=>$success,
            "error" => $error
        ]
    ]);
 //send_response($response);
}


function write_message_to_file($message)
{
$myFile = "test.txt";
$fh = fopen($myFile, 'a') or die("can't open file");
@fwrite($fh, $message);
@fclose($fh);
}

/**
 * Implements the task feature. Sends messages to SMSsync to be sent as
 * SMS to users.
 */
function send_task()
{
/**
 * Comment the code below out if you want to send an instant
 * reply as SMS to the user.
 *
 * This feature requires the "Get reply from server" checked on SMSsync.
 */
if (isset($_GET['task']) AND $_GET['task'] === 'send')
{
    $m = "Sample Task Message";
    $f = "+000-000-0000";
    $s = "true";
    $reply[0] = [
        "to" => $f,
        "message" => $m,
        "uuid" => "1ba368bd-c467-4374-bf28"
    ];
    // Send JSON response back to SMSsync
    $response = json_encode(
        ["payload"=>[
            "success"=>$s,
            "task"=>"send",
            "secret" => "123456",
            "messages"=>array_values($reply)]
        ]);
    send_response($response);
    }
}


function send_instant_message($to)
{
$m = "Your message has been received";
$f = "+000-000-0000";
$s = true;
$reply[0] = [
    "to" => $to,
    "message" => $m,
    "uuid" => "1ba368bd-c467-4374-bf28"
];
// Send JSON response back to SMSsync
$response = json_encode(
    ["payload"=>[
        "success"=>$s,
        "task"=>"send",
        "secret" => "123456",
        "messages"=>array_values($reply)]
    ]);
send_response($response);
}

function send_response($response)
{
// Avoid caching
header("Cache-Control: no-cache, must-revalidate"); // HTTP/1.1
header("Expires: Sat, 26 Jul 1997 05:00:00 GMT"); // Date in the past
header("Content-type: application/json; charset=utf-8");
echo $response;
}

function get_sent_message_uuids()
{
$data = file_get_contents('php://input');
$queued_messages = file_get_contents('php://input');
// Writing this to a file for demo purposes.
// In production, you will have to process the JSON string
// and remove the messages from the database or where ever the
// messages are stored so the next Task run, the server won't add
// these messages.
write_message_to_file($queued_messages."nn");
send_message_uuids_waiting_for_a_delivery_report($queued_messages);

}

function send_message_uuids_waiting_for_a_delivery_report($queued_messages)
{
// Send back the received messages UUIDs back to SMSsync
$json_obj = json_decode($queued_messages);
$response = json_encode(
[
    "message_uuids"=>$json_obj->queued_messages
]);
send_response($response);
}

function send_messages_uuids_for_sms_delivery_report()
{
if(isset($_GET['task']) AND $_GET['task'] == 'result'){
    $response = json_encode(
    [
        "message_uuids" => ['1ba368bd-c467-4374-bf28']
    ]);
    send_response($response);
    }

}

function get_sms_delivery_report()
{
if($_GET['task'] === 'result' AND $_GET['secret']=== '123456')
{
    $message_results = file_get_contents('php://input');
    write_message_to_file("message ".$message_results."nn");
    }
}


if($_SERVER['REQUEST_METHOD'] === 'POST')
{
if(isset($_GET['task']) AND $_GET['task'] === 'result'){
    get_sms_delivery_report();
}
else if( isset($_GET['task']) && $_GET['task'] === 'sent')
{
    get_sent_message_uuids();
}
else
{
    get_message();
    }
}
else
{
send_task();
send_messages_uuids_for_sms_delivery_report();
}

<?php


/**
 * Gets the messages(SMSs) sent by SMSsync as a POST request.
 *
 */
function get_message()
{
    $error = NULL;
    // Set success to false as the default success status
    $success = false;
    /**
     *  Get the phone number that sent the SMS.
     */
    if (isset($_POST['from']))
    {
        $from = $_POST['from'];
    }
    else
    {
        $error = 'The from variable was not set';
    }
    /**
     * Get the SMS aka the message sent.
     */
    if (isset($_POST['message']))
    {
        $message = $_POST['message'];
    }
    else
    {
        $error = 'The message variable was not set';
    }
    /**
     * Get the secret key set on SMSsync side
     * for matching on the server side.
     */
    if (isset($_POST['secret']))
    {
        $secret = $_POST['secret'];
    }
    /**
     * Get the timestamp of the SMS
     */
    if(isset($_POST['sent_timestamp']))
    {
        $sent_timestamp = $_POST['sent_timestamp'];
    }
    /**
     * Get the phone number of the device SMSsync is
     * installed on.
     */
    if (isset($_POST['sent_to']))
    {
        $sent_to = $_POST['sent_to'];
    }
    /**
     * Get the unique message id
     */
    if (isset($_POST['message_id']))
    {
        $message_id = $_POST['message_id'];
    }
    /**
     * Get device ID
     */
    if (isset($_POST['device_id']))
    {
        $device_id = $_POST['device_id'];
    }
    /**
     * Now we have retrieved the data sent over by SMSsync
     * via HTTP. Next thing to do is to do something with
     * the data. Either echo it or write it to a file or even
     * store it in a database. This is entirely up to you.
     * After, return a JSON string back to SMSsync to know
     * if the web service received the message successfully or not.
     *
     * In this demo, we are just going to save the data
     * received into a text file.
     *
     */
    if ((strlen($from) > 0) AND (strlen($message) > 0) AND
        (strlen($sent_timestamp) > 0 )
        AND (strlen($message_id) > 0))
    {
        /* The screte key set here is 123456. Make sure you enter
         * that on SMSsync.
         */
        if ( ( $secret == '123456'))
        {
            $success = true;
        } else
        {
            $error = "The secret value sent from the device does not match the one on the server";
        }
        // now let's write the info sent by SMSsync
        //to a file called test.txt
        $string = "From: ".$from."n";
        $string .= "Message: ".$message."n";
        $string .= "Timestamp: ".$sent_timestamp."n";
        $string .= "Messages Id:" .$message_id."n";
        $string .= "Sent to: ".$sent_to."n";
        $string .= "Device ID: ".$device_id."nnn";
        write_message_to_file($string);
    }
    /**
     * Comment the code below out if you want to send an instant
     * reply as SMS to the user.
     *
     * This feature requires the "Get reply from server" checked on SMSsync.
     */
     send_instant_message($from);
    /**
      * Now send a JSON formatted string to SMSsync to
      * acknowledge that the web service received the message
      */
     $response = json_encode([
        "payload"=> [
            "success"=>$success,
                "error" => $error
            ]
        ]);
     //send_response($response);
}

/**
 * Writes the received responses to a file. This acts as a database.
 */
function write_message_to_file($message)
{
    $myFile = "test.txt";
    $fh = fopen($myFile, 'a') or die("can't open file");
    @fwrite($fh, $message);
    @fclose($fh);
}




$servername = "localhost";
$username = "username";
$password = "";
$dbname = "my_db";

try {
    $conn = new PDO("mysql:host=$servername;dbname=$dbname", $username, $password);
    // set the PDO error mode to exception
    $conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
    $sql = "INSERT INTO my_db (sms_text, sent_dt)
    VALUES ('$message', '$sent_timestamp')";
    // use exec() because no results are returned
    $conn->exec($sql);
    echo "New record created successfully";
    }
catch(PDOException $e)
    {
    echo $sql . "<br>" . $e->getMessage();
    }

$conn = null;






/**
 * Implements the task feature. Sends messages to SMSsync to be sent as
 * SMS to users.
 */
function send_task()
{
    /**
     * Comment the code below out if you want to send an instant
     * reply as SMS to the user.
     *
     * This feature requires the "Get reply from server" checked on SMSsync.
     */
    if (isset($_GET['task']) AND $_GET['task'] === 'send')
    {
        $m = "Sample Task Message";
        $f = "+000-000-0000";
        $s = "true";
        $reply[0] = [
            "to" => $f,
            "message" => $m,
            "uuid" => "1ba368bd-c467-4374-bf28"
        ];
        // Send JSON response back to SMSsync
        $response = json_encode(
            ["payload"=>[
                "success"=>$s,
                "task"=>"send",
                "secret" => "123456",
                "messages"=>array_values($reply)]
            ]);
        send_response($response);
    }
}

/**
 * This sends an instant response when the server receive messages(SMSs) from
 * SMSsync. This requires the settings "Get Reply from Server" enabled on
 * SMSsync.
 */
function send_instant_message($to)
{
    $m = "Your message has been received";
    $f = "+000-000-0000";
    $s = true;
    $reply[0] = [
        "to" => $to,
        "message" => $m,
        "uuid" => "1ba368bd-c467-4374-bf28"
    ];
    // Send JSON response back to SMSsync
    $response = json_encode(
        ["payload"=>[
            "success"=>$s,
            "task"=>"send",
            "secret" => "123456",
            "messages"=>array_values($reply)]
        ]);
    send_response($response);
}

function send_response($response)
{
    // Avoid caching
    header("Cache-Control: no-cache, must-revalidate"); // HTTP/1.1
    header("Expires: Sat, 26 Jul 1997 05:00:00 GMT"); // Date in the past
    header("Content-type: application/json; charset=utf-8");
    echo $response;
}

function get_sent_message_uuids()
{
    $data = file_get_contents('php://input');
    $queued_messages = file_get_contents('php://input');
    // Writing this to a file for demo purposes.
    // In production, you will have to process the JSON string
    // and remove the messages from the database or where ever the
    // messages are stored so the next Task run, the server won't add
    // these messages.
    write_message_to_file($queued_messages."nn");
    send_message_uuids_waiting_for_a_delivery_report($queued_messages);

}

/**
 * Sends message UUIDS to SMSsync for their sms delivery status report.
 * When SMSsync send messages from the server as SMS to phone numbers, SMSsync
 * can send back status delivery report for these messages.
 */
function send_message_uuids_waiting_for_a_delivery_report($queued_messages)
{
    // Send back the received messages UUIDs back to SMSsync
    $json_obj = json_decode($queued_messages);
    $response = json_encode(
    [
        "message_uuids"=>$json_obj->queued_messages
    ]);
    send_response($response);
}

function send_messages_uuids_for_sms_delivery_report()
{
    if(isset($_GET['task']) AND $_GET['task'] == 'result'){
        $response = json_encode(
        [
            "message_uuids" => ['1ba368bd-c467-4374-bf28']
        ]);
        send_response($response);
    }

}

/**
 * Get status delivery report on sent messages
 *
 */
function get_sms_delivery_report()
{
    if($_GET['task'] === 'result' AND $_GET['secret']=== '123456')
    {
        $message_results = file_get_contents('php://input');
        write_message_to_file("message ".$message_results."nn");
    }
}

// Execute functions above
if($_SERVER['REQUEST_METHOD'] === 'POST')
{
    if(isset($_GET['task']) AND $_GET['task'] === 'result'){
        get_sms_delivery_report();
    }
    else if( isset($_GET['task']) && $_GET['task'] === 'sent')
    {
        get_sent_message_uuids();
    }
    else
    {
        get_message();
    }
}
else
{
    send_task();
    send_messages_uuids_for_sms_delivery_report();
}


?>