<?php

/**
 * Helper functions for the conversation messages
 */

use Symfony\Component\Mime\Email;
use Symfony\Component\Mime\Address;
use Symfony\Component\Mailer\Mailer;
use Symfony\Component\Mailer\Transport\Transport;
use Symfony\Component\Mailer\Exception\TransportExceptionInterface;
use PhpImap\Mailbox;
use phpseclib3\Net\SSH2;
use phpseclib3\Crypt\PublicKeyLoader;


if (!defined('ABSPATH')) {
    exit;
}

class RL_MailWarmer_Message_Handler {

    /**
     * Process pending messages.
     */
    public static function process_pending_messages() {
        // log_to_file("process_pending_messages - Running");
        global $wpdb;
        $results = [
            'success' => 0,
            'failure' => 0,
        ];

        // Fetch the next 100 pending messages with scheduled timestamps in the past
        $table_name = $wpdb->prefix . 'rl_mailwarmer_messages';
        $messages = $wpdb->get_results(
            $wpdb->prepare(
                "SELECT * FROM $table_name WHERE status = %s AND scheduled_for_timestamp < %s ORDER BY scheduled_for_timestamp ASC LIMIT 10",
                'scheduled',
                current_time('mysql')
            ),
            ARRAY_A
        );

        // if (empty($messages)) {
        //     // log_to_file("process_pending_messages - messages empty");
        //     return;
        // }

        $messages_count = count($messages);
        if ($messages_count > 0) {
            action_log("process_pending_messages - Processing {$messages_count} messages" );

            foreach ($messages as $message) {
                log_to_file("==========================================================");
                try {
                    // if (!empty($message['first_message']) && $message['first_message']) {
                    //     log_to_file("process_pending_messages - trying send_message");
                    //     $result = self::send_message($message);
                    // } else {
                    //     log_to_file("process_pending_messages - trying reply_message");
                    //     $result = self::reply_message($message);
                    // }
                    log_to_file("process_pending_messages - trying send_message for {$message['id']} from {$message['from_email']} to ", $message['to_email']);
                    $result = self::send_message($message);

                    // Update message status to 'sent' on success
                    if ($result) {
                        self::update_message_status($message['id'], 'sent');
                        $results['success']++;
                        log_to_file("process_pending_messages - Success sending message: {$message['id']}");
                        action_log("process_pending_messages - Sent email {$message['id']} from {$message['from_email']} to ", $message['to_email']);
                    } else {
                        self::update_message_status($message['id'], 'failed');
                        log_to_file("process_pending_messages - Error sending message: {$message['id']}");
                        $results['failure']++;
                    }
                } catch (Exception $e) {
                    // Handle errors gracefully and log them
                    log_to_file('process_pending_messages - Error processing message ID ' . $message['id'] . ': ' . $e->getMessage());
                    self::update_message_status($message['id'], 'failed');
                    $results['failure']++;
                }
                // sleep(3);
            }
            log_to_file("process_pending_messages - Results: ", $results);
            action_log("process_pending_messages - Finished processing {$messages_count} messages with {$results['success']} sent and {$results['failure']} failures");
        }

        return $results;
    }

    /**
     * Send the first message in a conversation.
     *
     * @param array $message The message details.
     * @return bool True if the message is sent successfully, false otherwise.
     * @throws Exception If required fields are missing or an error occurs during sending.
     */
    public static function send_message($message) {
      // log_to_file("send_message - Running");
        // log_to_file("send_message - Message: ", $message);

        // Prepare email data and connection info
        $email_data = self::prepare_email_data($message);

      // log_to_file("send_message - Email Data: ", $email_data);

        // Extract connection info
        $connection_info = $email_data['connection_info'];
        if (!empty($connection_info['smtp_password'])) {
            $password = $connection_info['smtp_password'];
        } else {
            $password = $connection_info['mail_password'];
        }

        // Check required fields
        if (empty($email_data['to']) || empty($email_data['from']) || empty($email_data['subject']) || empty($email_data['text_body'])) {
            
          // log_to_file("send_message - Missing required fields for sending the email");
            throw new Exception(__('Missing required fields for sending the email.', 'rl-mailwarmer'));
        }

        // Create the SMTP transport
        try {
          // log_to_file("send_message - Creating Transport");
            // Create the SMTP transport
            $transport = new Symfony\Component\Mailer\Transport\Smtp\EsmtpTransport(
                $connection_info['smtp_server'],
                $connection_info['smtp_port']
            );

            // Set authentication details
            $transport->setUsername($email_data['from']);
            $transport->setPassword($password);

            $to_addresses = $email_data['to'];
            if (!is_array($to_addresses)) {
                $to_addresses = json_decode($to_addresses, true);
            }
            $to_addresses_type = gettype($to_addresses);
          // log_to_file("send_message - To ({$to_addresses_type}): ", $to_addresses);

            // Create the mailer
            $mailer = new Symfony\Component\Mailer\Mailer($transport);

            // Send an email
           
            $email_message = (new Symfony\Component\Mime\Email())
                ->from(new Address($email_data['from'], $email_data['name']))
                ->to(...$to_addresses)
                ->subject($email_data['subject'])
                ->text($email_data['text_body'])
                ->html($email_data['html_body']);

            // Add headers
            $campaign_tracking_id = $email_data['campaign_tracking_id'];
            // $previous_message_id = $message['previous_message_id'];
            // if ($previous_message_id) {
            //     $campaign_tracking_id .= '-' . $previous_message_id;
            // }
            $email_message->getHeaders()->addTextHeader('X-MFTID', $campaign_tracking_id);
          // log_to_file("send_message - Creating email with MFTID: {$campaign_tracking_id}");

          // log_to_file("send_message - Trying to send email.");
            $smtp_result = $mailer->send($email_message);

          // log_to_file("send_message - Message sent!", $smtp_result);
            return true;
        } catch (TransportExceptionInterface $e) {
            log_to_file("send_message - Error sending email {$message['id']}: " . $e->getMessage());
            return false;
        }
    }

    public static function search_email_by_x_mftid($imap_stream, $imap_server, $campaign_tracking_id) {
        $folders = imap_list($imap_stream, $imap_server, '*');
        $result = ['folder' => null, 'email' => null];

        $search_term = '/X\-MFTID: ' . preg_quote($campaign_tracking_id, '/') . '.+/i';
        log_to_file("search_email_by_x_mftid - search term: {$search_term}");

        foreach ($folders as $folder) {
            $decoded_folder = imap_utf7_decode($folder);
            // log_to_file("search_email_by_x_mftid - decoded_folder: ", $decoded_folder);

            $status = imap_status($imap_stream, $decoded_folder, SA_MESSAGES);
            if ($status->messages > 0) {
                log_to_file("search_email_by_x_mftid - Searching {$decoded_folder}");
                $emails = imap_search($imap_stream, 'TEXT "' . $campaign_tracking_id . '"', SE_UID);
                if ($emails) {
                    $result['folder'] = $decoded_folder;
                    $result['email'] = $emails;
                    break;
                }
            }
        }
        return $result;
    }

    /**
     * Prepare email data and fetch connection info.
     *
     * @param array $message The message data.
     * @return array Prepared email data and connection info.
     * @throws Exception If required data is missing.
     */
    private static function prepare_email_data($message) {
        // log_to_file("prepare_email_data - Running");
        // log_to_file("prepare_email_data - Message: ", $message);

        // Ensure 'from' is valid and fetch connection info
        if (empty($message['from_email'])) {
            throw new Exception(__('Missing "from" address in the message.', 'rl-mailwarmer'));
        }

        // Find the email-account post matching the 'from' address
        $from_post_id = self::find_email_account_by_address($message['from_email']);
        if (!$from_post_id) {
            throw new Exception(__('No matching email account found for "from" address.', 'rl-mailwarmer'));
        }

        // Fetch connection details
        // log_to_file("prepare_email_data - Getting connection info");
        $full_name = get_post_meta($from_post_id, 'full_name', true);
        $mail_password = get_post_meta($from_post_id, 'mail_password', true);
        $email_provider_id = get_post_meta($from_post_id, 'email_provider', true);
        $connection_info = RL_MailWarmer_Email_Helper::get_provider_defaults($email_provider_id);
        $connection_info['username'] = $message['from_email'];
        $connection_info['mail_password'] = $mail_password;
        // log_to_file("prepare_email_data - Connection Info: ", $connection_info);

        // Override provider defaults with account-specific settings
        foreach (['smtp_server', 'smtp_port', 'smtp_password', 'imap_server', 'imap_port', 'imap_password'] as $key) {
            $meta_value = get_post_meta($from_post_id, $key, true);
            if (!empty($meta_value)) {
                $connection_info[$key] = $meta_value;
            }
        }

        // Handle recipients
        // log_to_file("prepare_email_data - Handling recipients");
        // $to_emails = json_decode();
        $to_emails = is_array($message['to_email']) ? $message['to_email'] : json_decode($message['to_email']);
        $cc_emails = is_array($message['cc']) ? $message['cc'] : json_decode($message['cc']);

        $campaign_tracking_id = $message['campaign_tracking_id'] . '-' . $message['id'];
        $previous_message_id = $message['previous_message_id'];
        $text_body = $message['body'] . "\n\n" . $campaign_tracking_id;
        $html_body = $message['body'] . "<br /><br /><span style='font-size:0.5rem;'>{$campaign_tracking_id}</span>";

        return [
            'id'              => $message['id'],
            'connection_info' => $connection_info,
            'to'              => array_filter(array_map('trim', array_map('stripslashes', $to_emails))),
            'cc'              => array_filter(array_map('trim', array_map('stripslashes', $cc_emails))),
            'subject'         => $message['subject'],
            'text_body'            => $text_body,
            'html_body'            => $html_body,
            'from'            => $message['from_email'],
            'name'            => $full_name,
            'campaign_tracking_id'  => $campaign_tracking_id,
            'previous_message_id'  => $previous_message_id,
        ];
    }

    /**
     * Find the email-account post ID by email address.
     *
     * @param string $email_address The email address to search for.
     * @return int|null The post ID if found, or null.
     */
    private static function find_email_account_by_address($email_address) {
        // log_to_file("find_email_account_by_address - Searching for: $email_address");
        $query = new WP_Query([
            'post_type'   => 'email-account',
            'post_status' => 'publish',
            'title'       => $email_address,
            'fields'      => 'ids',
        ]);

        if (!empty($query->posts)) {
            return $query->posts[0];
        } else {
            return new WP_Error('find_email_account_by_address - Unable to find a matching email address');
        }
    }

    /**
     * Update the status of a message.
     *
     * @param int    $message_id The ID of the message to update.
     * @param string $status     The new status ('completed', 'failed', etc.).
     * @return void
     */
    private static function update_message_status($message_id, $status) {
        global $wpdb;

        $table_name = $wpdb->prefix . 'rl_mailwarmer_messages';

        $wpdb->update(
            $table_name,
            ['status' => $status],
            ['id' => $message_id],
            ['%s'],
            ['%d']
        );
    }

    // /**
    //  * Reply to an email message.
    //  *
    //  * @param array $message The message details.
    //  * @return bool True if the message is replied to successfully, false otherwise.
    //  * @throws Exception If required fields are missing or an error occurs.
    //  */
    // public static function reply_message($message) {
    //     // Prepare email data and connection info
    //     $email_data = self::prepare_email_data($message);
    //     log_to_file("reply_message - Email Data: ", $email_data);

    //     // Validate required fields
    //     if (empty($email_data['to']) || empty($email_data['from']) || empty($email_data['subject']) || empty($email_data['text_body'])) {
    //         throw new Exception(__('Missing required fields for replying to the email.', 'rl-mailwarmer'));
    //     }

    //     // Extract connection info
    //     $connection_info = $email_data['connection_info'];
    //     $emails = '';


    //     try {
    //         // log_to_file("reply_message - Trying to reply via IMAP {$connection_info['imap_server']}:{$connection_info['imap_port']}");
    //         // $imap = new \PhpImap\Mailbox(
    //         //     sprintf('{%s:%s/imap/ssl}', $connection_info['imap_server'], $connection_info['imap_port']),
    //         //     $connection_info['username'],
    //         //     $connection_info['mail_password'],
    //         //     null,
    //         //     'UTF-8'
    //         // );

    //         // $imap->checkMailbox();

    //         // // Search for the email with the matching subject
    //         // log_to_file("reply_message - Searching for message with X-MFTID");
    //         // $emails = $imap->searchMailbox('HEADER X-MFTID "' . addslashes($email_data['campaign_tracking_id']) . '"');


    //         $password = $connection_info['mail_password'];
    //         $email = $connection_info['username'];
            
    //         log_to_file("reply_message - Trying to reply via IMAP for {$email} using: ", $connection_info);

    //         $imap_server = '{' . $connection_info['imap_server'] . ':' . $connection_info['imap_port'] . '/imap/ssl}';

    //         log_to_file("reply_message - Trying to open stream for {$email} : {$password} @ {$imap_server}");
    //         // Try connecting to the IMAP server
    //         $imap_stream = @imap_open(
    //             $imap_server,
    //             $email,
    //             $password
    //         );

    //         if ($imap_stream) {
    //             log_to_file("reply_message - IMAP stream opened.");
    //             $imap_search_result = self::search_email_by_x_mftid($imap_stream, $imap_server, $email_data['campaign_tracking_id']);
    //             if ($imap_search_result['folder']) {
    //                 log_to_file("reply_message - Email with X-MFTID found in folder: {$imap_search_result['folder']}");
    //                 log_to_file("reply_message - Email: ", $imap_search_result['email']);
    //                 // $emails = $imap_search_result['email'];
    //                 // Continue with reply logic
    //             } else {
    //                 log_to_file("No email found with X-MFTID: " . $email_data['campaign_tracking_id']);
    //             }
    //             imap_close($imap_stream);
    //         }


    //         if (!empty($emails)) {


    //             // Fetch the email data
    //             $original_email = $imap->getMail($emails[0]);
    //             log_to_file("reply_message - Message found!");
    //             // log_to_file("reply_message - IMAP Message: ", $original_email);

    //             // Step 2: Send the reply via SMTP
    //             $transport = new Symfony\Component\Mailer\Transport\Smtp\EsmtpTransport(
    //                 $connection_info['smtp_server'],
    //                 $connection_info['smtp_port']
    //             );

    //             // Set authentication details
    //             $transport->setUsername($connection_info['username']);
    //             $transport->setPassword($connection_info['mail_password']);
    //             $to_addresses = $email_data['to'];
    //             if (!is_array($to_addresses)) {
    //                 $to_addresses = json_decode($to_addresses, true);
    //             }

    //             $mailer = new Mailer($transport);

    //             $reply_email = (new Email())
    //                 ->from(new Address($email_data['from'], $email_data['name']))
    //                 ->to(...$to_addresses)
    //                 ->subject('Re: ' . $original_email->subject)
    //                 ->text($email_data['text_body'])
    //                 ->html($email_data['html_body']);

    //             // Add headers
    //             $campaign_tracking_id = $email_data['campaign_tracking_id'];
    //             $reply_email->getHeaders()->addTextHeader('X-MFTID', $campaign_tracking_id);

    //             // Add headers for threading
    //             $headers = $reply_email->getHeaders();
    //             $headers->addTextHeader('In-Reply-To', $original_email->messageId);
    //             $headers->addTextHeader('References', trim($original_email->headers->references . ' ' . $original_email->messageId));

    //                 // ->addHeader('In-Reply-To', $original_email->messageId)
    //                 // ->addHeader('References', trim($original_email->headers->references . ' ' . $original_email->messageId));

    //             // if (!empty($email_data['cc'])) {
    //             //     $reply_email->cc(...$email_data['cc']);
    //             // }

    //             $mailer->send($reply_email);

    //             log_to_file("reply_message - Successfully sent IMAP/SMTP reply from ", $email_data['from']);

    //             // Step 3: Upload the reply to the Sent folder
    //             $imap_stream = imap_open(
    //                 sprintf('{%s:%d/imap/ssl}', $connection_info['imap_server'], $connection_info['imap_port']),
    //                 $connection_info['username'],
    //                 $connection_info['mail_password']
    //             );

    //             $raw_message = $reply_email->toString(); // Convert the Email object to raw MIME format
    //             imap_append($imap_stream, sprintf('{%s}/Sent', $connection_info['imap_server']), $raw_message);

    //             imap_close($imap_stream);

    //             // Create the reply headers
    //             // $reply_headers = [
    //             //     'In-Reply-To' => $original_email->messageId,
    //             //     'References'  => trim($original_email->headers->references . ' ' . $original_email->messageId),
    //             // ];

    //             // // Construct the reply body
    //             // $reply_body = $email_data['body'] . "\n\n" .
    //             //     'On ' . $original_email->date . ', ' . $original_email->fromName . ' <' . $original_email->fromAddress . '> wrote:' . "\n" .
    //             //     $original_email->textPlain;

    //             // // Send the reply via IMAP
    //             // log_to_file("reply_message - Sending message via IMAP");
    //             // $imap->addMessageToSentFolder(
    //             //     'To: ' . implode(', ', $email_data['to']) . "\r\n" .
    //             //     'Cc: ' . implode(', ', $email_data['cc']) . "\r\n" .
    //             //     'Subject: Re: ' . $original_email->subject . "\r\n" .
    //             //     'From: ' . $email_data['from'] . "\r\n" .
    //             //     'In-Reply-To: ' . $reply_headers['In-Reply-To'] . "\r\n" .
    //             //     'References: ' . $reply_headers['References'] . "\r\n" .
    //             //     "\r\n" .
    //             //     $reply_body
    //             // );
    //             // log_to_file("reply_message - Done message via IMAP");

    //             // $mailer = new Mailer($transport);
    //             // $mailer->send($reply);

    //             return true; // Reply sent successfully
    //         } else {
    //             log_to_file("reply_message - Unable to reply via IMAP. Falling back to SMTP");
    //         }
    //     } catch (Exception $e) {
    //         log_to_file('reply_message - IMAP Error: ' . $e->getMessage());
    //     }

    //     // Fallback to SMTP if IMAP fails
    //     try {
    //         log_to_file("reply_message - Falling back to SMTP");

    //         $result = self::send_message($message);
    //         return $result;
    //         // $to_addresses = $email_data['to'];
    //         // if (!is_array($to_addresses)) {
    //         //     $to_addresses = json_decode($to_addresses, true);
    //         // }
    //         // log_to_file("reply_message - Creating SMTP message");

    //         // $smtp_reply = (new Email())
    //         //     ->from(new Address($email_data['from'], $email_data['name']))
    //         //     ->to(...$to_addresses)
    //         //     ->subject($email_data['subject'])
    //         //     ->text($email_data['text_body'])
    //         //     ->html($email_data['html_body']);

    //         // // Add headers
    //         // $campaign_tracking_id = $email_data['campaign_tracking_id'];
    //         // $smtp_reply->getHeaders()->addTextHeader('X-MFTID', $campaign_tracking_id);

    //         // // Add CCs if present
    //         // // if (!empty($email_data['cc'])) {
    //         // //     $smtp_reply->cc(...$email_data['cc']);
    //         // // }

    //         // // Create the SMTP transport
    //         // log_to_file("reply_message - Creating SMTP transport");

    //         // $transport = new Symfony\Component\Mailer\Transport\Smtp\EsmtpTransport(
    //         //     $connection_info['smtp_server'],
    //         //     $connection_info['smtp_port']
    //         // );

    //         // // Set authentication details
    //         // $transport->setUsername($connection_info['username']);
    //         // $transport->setPassword($connection_info['mail_password']);

    //         // // Create the mailer
    //         // log_to_file("reply_message - Creating SMTP mailer");
    //         // $mailer = new Symfony\Component\Mailer\Mailer($transport);
    //         // $smtp_result = $mailer->send($smtp_reply);
    //         // log_to_file("reply_message - Sent reply via fallback SMTP from {$email_data['from']}:", $smtp_result);
    //         // // log_to_file('reply_message - SMTP Send Success (?)');

    //          // Fallback SMTP reply sent successfully
    //     } catch (Exception $e) {
    //         log_to_file('reply_message - SMTP Error: ' . $e->getMessage());
    //         return false; // Reply failed
    //     }
    // }


}