<?php
/**
 * Messenger Bot Class.
 * @author Pablo Montenegro
 * @about Based on the Telegram API wrapper by Gabriele Grillo <gabry.grillo@alice.it>
 * TODO:
 * https://developers.facebook.com/docs/messenger-platform/send-api-reference/buy-button
 * https://developers.facebook.com/docs/messenger-platform/send-api-reference/url-button
 * https://developers.facebook.com/docs/messenger-platform/send-api-reference/image-attachment
 * https://developers.facebook.com/docs/messenger-platform/send-api-reference/sender-actions
 * https://developers.facebook.com/docs/messenger-platform/send-api-reference/errors
 */
class bm_Messenger {
    private $bot_id = "";
    private $api_version = "v2.9";
    private $data = array();
    /// Class constructor
    public function __construct($bot_id) {
        $this->bot_id = $bot_id;
        $this->data = $this->getData();
    }
    /// Verify webhook
    public function verifyWebhook($hub_token) {
        if ($this->data['hub_verify_token'] == $hub_token) {
            return $this->data['hub_challenge'];
        }
        return false;
    }
    /// Do requests to Messenger Bot API
    public function endpoint($api, array $content, $post = true) {
        $url = 'https://graph.facebook.com/' . $this->api_version . '/' . $api . '?access_token=' . $this->bot_id;
        if ($post)
            $reply = $this->sendAPIRequest($url, $content);
        else
            $reply = $this->sendAPIRequest($url, array(), false);
        return json_decode($reply, true);
    }
    public function respondSuccess() {
        http_response_code(200);
        return json_encode(array("status" => "success"));
    }
    // send chat action
    // sender_action:
    // mark_seen
    // typing_on
    // typing_off
    public function sendChatAction($chat_id, $action) {
        return $this->endpoint("me/messages", array(
            'recipient' => array(
                'id' => $chat_id
            ),
            'sender_action' => $action
        )
                              );
    }
    // send message
    //        https://developers.facebook.com/docs/messenger-platform/send-api-reference#request


    public function sendMessage($chat_id, $type, $text, $args = null) {
        $seen = $this->sendChatAction($chat_id, 'mark_seen');

        //sleep(1);

        $typing_on = $this->sendChatAction($chat_id, 'typing_on');

        //sleep(2);

        if($type == 'text'){
            $result = $this->sendText($chat_id, $text);
        }

        if($type == 'buttons'){
            $result = $this->sendButtonTemplate($chat_id, $text, $args);
        }

        $typing_off = $this->sendChatAction($chat_id, 'typing_off');

        return $result;
    }


    public function sendText($chat_id, $text) {
        return $this->endpoint("me/messages", array(
            'recipient' => array(
                'id' => $chat_id
            ),
            'message' => array(
                'text' => $text
            )
        )
                              );
    }
    // send message
    //        $button = array(
    //            array(
    //                    'type' => 'web_url',
    //                    'url' => 'URL_HERE',
    //                    'title' => 'TITLE_HERE'
    //                ),
    //            array(
    //                'type' => 'web_url',
    //                'url' => 'URL_HERE',
    //                'title' => 'TITLE_HERE'
    //            ),
    //            ...
    //        );
    //        $elements = array(
    //            array(
    //            'title' => 'TITLE_TEXT_HERE',
    //            'item_url' => 'ITEM_URL_HERE',
    //            'image_url' => 'IMAGE_URL_HERE',
    //            'subtitle' => 'SUBTITLE_HERE',
    //            'buttons' => $buttons
    //            )
    //        );
    //        https://developers.facebook.com/docs/messenger-platform/send-api-reference#request
    public function sendGenericTemplate($chat_id, array $elements) {
        return $this->endpoint("me/messages", array(
            'recipient' => array(
                'id' => $chat_id
            ),
            'message' => array(
                'attachment' => array(
                    'type' => 'template',
                    'payload' => array(
                        'template_type' => 'generic',
                        'elements' => $elements
                    )
                )
            )
        )
                              );
    }
    // send quick reply
    //        $replies = array(
    //            array(
    //                    'content_type' => 'text',
    //                    'title' => 'TITLE_HERE',
    //                    'payload' => 'DEVELOPER_CUSTOM_PAYLOAD_HERE'
    //                ),
    //            array(
    //                'content_type' => 'text',
    //                'title' => 'TITLE_HERE',
    //                'payload' => 'DEVELOPER_CUSTOM_PAYLOAD_HERE'
    //            ),
    //            ...
    //        );
    //        https://developers.facebook.com/docs/messenger-platform/send-api-reference/quick-replies
    public function sendQuickReply($chat_id, $text, array $replies) {
        return $this->endpoint("me/messages", array(
            'recipient' => array(
                'id' => $chat_id
            ),
            'message' => array(
                'text' => $text,
                'quick_replies' => $replies
            )
        )
                              );
    }
    // send button
    //        $buttons = array(
    //            array(
    //                    'type' => 'web_url',
    //                    'url' => 'URL_HERE',
    //                    'title' => 'TITLE_HERE'
    //                ),
    //            array(
    //                'type' => 'web_url',
    //                'url' => 'URL_HERE',
    //                'title' => 'TITLE_HERE'
    //            ),
    //            ...
    //        );
    //        https://developers.facebook.com/docs/messenger-platform/send-api-reference/button-template
    //        https://developers.facebook.com/docs/messenger-platform/send-api-reference/share-button <- works only with sendGenericTemplate
    public function sendButtonTemplate($chat_id, $text, array $buttons) {
        return $this->endpoint("me/messages",
                               array(
                                   'recipient' => array(
                                       'id' => $chat_id
                                   ),
                                   'message' => array(
                                       'attachment' => array(
                                           'type' => 'template',
                                           'payload' => array(
                                               'template_type' => 'button',
                                               'text' => $text,
                                               'buttons' => $buttons
                                           )
                                       )
                                   )
                               )
                              );
    }
    // send elements
    //        $elements = array(
    //            array(
    //            'title' => 'TITLE_TEXT_HERE',
    //            'item_url' => 'ITEM_URL_HERE',
    //            'image_url' => 'IMAGE_URL_HERE',
    //            'subtitle' => 'SUBTITLE_HERE',
    //            'buttons' => $buttons
    //            )
    //        );
    //        https://developers.facebook.com/docs/messenger-platform/send-api-reference/receipt-template
    public function sendReceiptTemplate($chat_id, array $payload) {
        return $this->endpoint("me/messages",
                               array(
                                   'recipient' => array(
                                       'id' => $chat_id
                                   ),
                                   'message' => array(
                                       'attachment' => array(
                                           'type' => 'template',
                                           'payload' => $payload
                                       )
                                   )
                               )
                              );
    }
    /// Get the text of the current message
    public function Attachments() {
        $attachments = $this->data["entry"][0]["messaging"][0]["message"]["attachments"];
        $get_attachments = array();
		if( isset($attachments) && !empty($attachments) ){
        foreach($attachments as $attachment){
            $get_attachments[] = $attachment["payload"];
        }
		}
        return $get_attachments;
    }
    /// Get the text of the current message
    public function Text() {
        return $this->data["entry"][0]["messaging"][0]["message"]["text"];
    }
    /// Get the userdata who sent the message
    public function UserData($chat_id) {
        return $this->endpoint($chat_id, array(), false);
    }
    /// Get the chat_id of the current message
    public function ChatID() {
        return $this->data['entry'][0]['messaging'][0]['sender']['id'];
    }
    /// Get the recipient_id of the current message
    public function RecipientID() {
        return $this->data['entry'][0]['messaging'][0]['recipient']['id'];
    }
    /// Get raw data
    public function RawData() {
        return $this->data;
    }
    /// Get m.me ref type
    public function getReferralType() {
        return $this->data["entry"][0]["messaging"][0]["referral"]["type"];
    }
    /// Get m.me ref data
    public function getReferralRef() {
        return $this->data["entry"][0]["messaging"][0]["referral"]["ref"];
    }
    /// Get payload
    public function getPayload() {
        return $this->data["entry"][0]["messaging"][0]["postback"]["payload"];
    }
    /// Get quickreply payload
    public function getQuickReplyPayload() {
        return $this->data["entry"][0]["messaging"][0]["message"]["quick_reply"]["payload"];
    }
    /// Get message timestamp
    public function getMessageTimestamp() {
        return $this->data["entry"][0]["time"];
    }
    /// Get the message_id of the current message
    public function MessageID() {
        return $this->data["entry"][0]["messaging"][0]["message"]["mid"];
    }
    /// Get the is_echo of the current message
    public function getEcho() {
        return $this->data["entry"][0]["messaging"][0]["message"]["is_echo"];
    }
    /// Get the app_id of the current message
    public function getAppId() {
        return $this->data["entry"][0]["messaging"][0]["message"]["app_id"];
    }
    private function sendAPIRequest($url, array $content, $post = true, $response = true) {

        $response = wp_remote_post( $url, array(
            'method' => 'POST',
            'httpversion' => '1.0',
            'sslverify' => false,
            'headers' => array('Content-Type: application/json'),
            'body' => $content
        )
                                  );
        return $response['body'];	
        /*
        $ch = curl_init($url);
        if ($post) {
            curl_setopt($ch, CURLOPT_POST, 1);
            curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($content));
        }
        curl_setopt($ch, CURLOPT_HTTPHEADER, array('Content-Type: application/json'));
        if ($response)
            curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
        curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
        $result = curl_exec($ch);
        curl_close($ch);
        return $result;
		*/
    }
    /// Get the data of the current message
    public function getData() {
        if (!($this->data)) {
            $rawData = file_get_contents("php://input");
            return json_decode($rawData, true);
        } else {
            return $this->data;
        }
    }
}
// Helper for Uploading file using CURL
if (!function_exists('curl_file_create')) {
    function curl_file_create($filename, $mimetype = '', $postname = '') {
        return "@$filename;filename="
            . ($postname ? : basename($filename))
            . ($mimetype ? ";type=$mimetype" : '');
    }
}