PHP如何使用聊天机器人处理入门按钮Messenger回发

<?php
$access_token = '<Your_Facebook_Page_Access_Token>';

// 验证Webhook请求
$verify_token = '<Your_Webhook_Verify_Token>';
$hub_verify_token = null;

if (isset($_REQUEST['hub_challenge'])) {
    $challenge = $_REQUEST['hub_challenge'];
    $hub_verify_token = $_REQUEST['hub_verify_token'];
}

if ($hub_verify_token === $verify_token) {
    echo $challenge;
    exit;
}

// 获取Messenger的回调数据
$input = json_decode(file_get_contents('php://input'), true);

if (isset($input['entry'][0]['messaging'][0]['postback'])) {
    $postback_payload = $input['entry'][0]['messaging'][0]['postback']['payload'];

    // 根据回调payload执行相应的操作
    if ($postback_payload === 'GET_STARTED_PAYLOAD') {
        // 处理入门按钮回发
        // 这里可以编写你的逻辑代码，根据回发payload执行不同的操作
        // 例如发送欢迎消息、获取用户信息等

        // 发送消息给用户
        $sender_id = $input['entry'][0]['messaging'][0]['sender']['id'];
        $response_message = '欢迎使用聊天机器人！';
        send_message($sender_id, $response_message);
    }
}

function send_message($recipient_id, $message_text) {
    global $access_token;

    $message_data = [
        'recipient' => ['id' => $recipient_id],
        'message' => ['text' => $message_text]
    ];

    $api_url = "https://graph.facebook.com/v12.0/me/messages?access_token=$access_token";
    $curl = curl_init($api_url);
    curl_setopt($curl, CURLOPT_POST, true);
    curl_setopt($curl, CURLOPT_POSTFIELDS, json_encode($message_data));
    curl_setopt($curl, CURLOPT_HTTPHEADER, ['Content-Type: application/json']);
    curl_exec($curl);
    curl_close($curl);
}
?>