<?php
namespace DayTidy\Modules\Notifications;

use DayTidy\Entities\Booking as BookingEntity;
use DayTidy\Entities\Notification as NotificationEntity;

class EmailSender
{
    private RecipientResolver $recipients;
    private Renderer $renderer;
    private Ics $ics;
    private DeliveryLogRepository $logs;

    public function __construct()
    {
        $this->recipients = new RecipientResolver();
        $this->renderer = new Renderer();
        $this->ics = new Ics();
        $this->logs = new DeliveryLogRepository();
    }

    /**
     * @param mixed[] $args
     * @return mixed[]
     */
    public function send(NotificationEntity $notification, BookingEntity $booking, string $context, array $args = []): array
    {
        $template = isset($args['template']) && is_array($args['template'])
            ? $args['template']
            : $notification->template($context);
        $source = $this->source($args);
        $parent_log_id = absint($args['retry_of_log_id'] ?? 0);
        $attempt = $this->attempt($parent_log_id);

        $force = !empty($args['force']);
        if (!$force && empty($template['active']))
        {
            $log_id = $this->log($notification, $booking, $context, [], $template, DeliveryLog::STATUS_SKIPPED, $source, $attempt, $parent_log_id, esc_html__('Notification recipient is inactive.', 'daytidy'));

            return [
                'sent' => 0,
                'failed' => 0,
                'skipped' => 1,
                'messages' => [esc_html__('Notification recipient is inactive.', 'daytidy')],
                'log_ids' => [$log_id],
            ];
        }

        $recipients = isset($args['recipient']) && is_array($args['recipient'])
            ? [$args['recipient']]
            : (isset($args['test_to'])
            ? $this->testRecipients($args['test_to'], $context)
            : $this->recipients->resolve($booking, $context, $template));

        if (!count($recipients))
        {
            $log_id = $this->log($notification, $booking, $context, [], $template, DeliveryLog::STATUS_SKIPPED, $source, $attempt, $parent_log_id, esc_html__('No recipients were found.', 'daytidy'));

            return [
                'sent' => 0,
                'failed' => 0,
                'skipped' => 1,
                'messages' => [esc_html__('No recipients were found.', 'daytidy')],
                'log_ids' => [$log_id],
            ];
        }

        $suppress_extra = !empty($args['suppress_extra_recipients']);
        $placeholders = isset($args['placeholders']) && is_array($args['placeholders'])
            ? $args['placeholders']
            : [];
        $headers = $this->headers($template, $suppress_extra);
        $temp_files = [];
        $attachments = $this->attachments($template, $booking, $temp_files);

        $headers = (array) apply_filters(
            'DayTidy/F__DayTidy/Notifications__headers/headers',
            $headers,
            $notification,
            $booking,
            $context,
            $template
        );
        $attachments = (array) apply_filters(
            'DayTidy/F__DayTidy/Notifications__attachments/attachments',
            $attachments,
            $notification,
            $booking,
            $context,
            $template
        );

        $results = [
            'sent' => 0,
            'failed' => 0,
            'skipped' => 0,
            'messages' => [],
            'log_ids' => [],
        ];

        foreach ($recipients as $recipient)
        {
            $subject = wp_strip_all_tags($this->renderer->render($template, $booking, $recipient, 'subject', $placeholders));
            $message = $this->renderer->render($template, $booking, $recipient, 'content', $placeholders);

            if (apply_filters('DayTidy/F__DayTidy/Notifications__run_shortcodes/enabled', true, $template, $notification, $booking, $context))
            {
                $message = do_shortcode($message);
            }

            $message = wpautop($message);

            $subject = (string) apply_filters(
                'DayTidy/F__DayTidy/Notifications__subject/subject',
                $subject,
                $notification,
                $booking,
                $context,
                $recipient,
                $template
            );
            $message = (string) apply_filters(
                'DayTidy/F__DayTidy/Notifications__message/message',
                $message,
                $notification,
                $booking,
                $context,
                $recipient,
                $template
            );

            do_action(
                'DayTidy/A__DayTidy/Notifications__before_send',
                $notification,
                $booking,
                $context,
                $recipient,
                $subject,
                $message,
                $headers,
                $attachments
            );

            $sent = false;
            $mail_errors = [];
            $mail_failed = function ($error) use (&$mail_errors): void
            {
                if ($error instanceof \WP_Error) $mail_errors[] = $error->get_error_message();
            };

            add_action('wp_mail_failed', $mail_failed);

            try
            {
                $sent = wp_mail(
                    // Keep display names with commas intact; wp_mail() only comma-splits string recipients.
                    [$this->mailbox($recipient)],
                    $subject,
                    $message,
                    $headers,
                    $attachments
                );
            }
            catch (\Throwable $e)
            {
                $results['messages'][] = $e->getMessage();
                $mail_errors[] = $e->getMessage();
            }
            finally
            {
                remove_action('wp_mail_failed', $mail_failed);
            }

            if ($sent)
            {
                $results['sent']++;
                $log_id = $this->log($notification, $booking, $context, $recipient, $template, DeliveryLog::STATUS_SENT, $source, $attempt, $parent_log_id, '', $subject, $message);
                $results['log_ids'][] = $log_id;
            }
            else
            {
                $error = $this->mailError($mail_errors);
                if ($error !== '') $results['messages'][] = $error;

                $results['failed']++;
                $log_id = $this->log($notification, $booking, $context, $recipient, $template, DeliveryLog::STATUS_FAILED, $source, $attempt, $parent_log_id, $error, $subject, $message);
                $results['log_ids'][] = $log_id;
                do_action(
                    'DayTidy/A__DayTidy/Notifications__send_failed',
                    $notification,
                    $booking,
                    $context,
                    $recipient,
                    $subject,
                    $message,
                    $headers,
                    $attachments,
                    $error
                );
            }

            do_action(
                'DayTidy/A__DayTidy/Notifications__after_send',
                $notification,
                $booking,
                $context,
                $recipient,
                $sent,
                $subject,
                $message,
                $headers,
                $attachments,
                $log_id
            );
        }

        $this->cleanup($temp_files);

        return $results;
    }

    /**
     * @param mixed $to
     * @return mixed[]
     */
    private function testRecipients($to, string $context): array
    {
        $emails = is_array($to) ? $to : [$to];
        $recipients = [];

        foreach ($emails as $email)
        {
            $email = sanitize_email((string) $email);
            if (!is_email($email)) continue;

            $recipients[] = [
                'email' => $email,
                'name' => '',
                'context' => $context,
                'data' => [],
            ];
        }

        return $recipients;
    }

    /**
     * @param mixed[] $template
     * @return string[]
     */
    private function headers(array $template, bool $suppress_extra): array
    {
        $headers = ['Content-Type: text/html; charset=UTF-8'];
        if ($suppress_extra) return $headers;

        foreach (['cc' => 'Cc', 'bcc' => 'Bcc'] as $field => $header)
        {
            $enabled_field = $field . '_enabled';
            if (array_key_exists($enabled_field, $template) && empty($template[$enabled_field])) continue;

            foreach ($this->recipients->picker((array) ($template[$field] ?? [])) as $recipient)
            {
                $headers[] = $header . ': ' . $recipient['email'];
            }
        }

        return $headers;
    }

    /**
     * @param mixed[] $template
     * @param string[] $temp_files
     * @return string[]
     */
    private function attachments(array $template, BookingEntity $booking, array &$temp_files): array
    {
        $attachments = [];

        foreach ((array) ($template['attachments'] ?? []) as $attachment_id)
        {
            $path = get_attached_file((int) $attachment_id);
            if ($path && file_exists($path)) $attachments[] = $path;
        }

        if (!empty($template['attach_ical']))
        {
            $path = $this->ics->create($booking);
            if ($path)
            {
                $attachments[] = $path;
                $temp_files[] = $path;
            }
        }

        return $attachments;
    }

    /**
     * @param mixed[] $recipient
     */
    private function mailbox(array $recipient): string
    {
        $email = (string) ($recipient['email'] ?? '');
        $name = trim((string) ($recipient['name'] ?? ''));

        return $name ? $name . ' <' . $email . '>' : $email;
    }

    /**
     * @param string[] $paths
     */
    private function cleanup(array $paths): void
    {
        foreach ($paths as $path)
        {
            if (is_string($path) && file_exists($path)) wp_delete_file($path);
        }
    }

    /**
     * @param mixed[] $args
     */
    private function source(array $args): string
    {
        $source = sanitize_key((string) ($args['source'] ?? DeliveryLog::SOURCE_EVENT));

        return in_array($source, DeliveryLog::sources(), true) ? $source : DeliveryLog::SOURCE_EVENT;
    }

    private function attempt(int $parent_log_id): int
    {
        if (!$parent_log_id) return 1;

        $parent = $this->logs->find($parent_log_id);

        return $parent ? max(1, (int) ($parent->attempt ?? 1)) + 1 : 1;
    }

    /**
     * @param mixed[] $recipient
     * @param mixed[] $template
     */
    private function log(
        NotificationEntity $notification,
        BookingEntity $booking,
        string $context,
        array $recipient,
        array $template,
        string $status,
        string $source,
        int $attempt,
        int $parent_log_id,
        string $error,
        string $subject = '',
        string $body = ''
    ): int
    {
        if (!apply_filters('DayTidy/F__DayTidy/Notifications/EmailSender__logging/enabled', false, $notification, $booking, $context, $status, $source))
        {
            return 0;
        }

        [$logged_subject, $logged_body] = $this->loggedContent($notification, $template, $subject, $body);

        return $this->logs->insert([
            'notification_id' => $notification->id(),
            'booking_id' => $booking->id(),
            'trigger_key' => $notification->trigger(),
            'recipient_context' => $context,
            'recipient_email' => (string) ($recipient['email'] ?? ''),
            'recipient_name' => (string) ($recipient['name'] ?? ''),
            'recipient_snapshot' => $recipient,
            'subject' => $logged_subject,
            'body' => $logged_body,
            'status' => $status,
            'source' => $source,
            'attempt' => $attempt,
            'parent_log_id' => $parent_log_id,
            'error_message' => $error,
        ]);
    }

    /**
     * @param mixed[] $template
     * @return array{0: string, 1: string}
     */
    private function loggedContent(NotificationEntity $notification, array $template, string $subject, string $body): array
    {
        if ($notification->trigger() === Registry::TRIGGER_CUSTOMER_PORTAL_VERIFICATION_CODE)
        {
            return [
                (string) ($template['subject'] ?? ''),
                (string) ($template['content'] ?? ''),
            ];
        }

        return [
            $subject !== '' ? $subject : (string) ($template['subject'] ?? ''),
            $body,
        ];
    }

    /**
     * @param string[] $errors
     */
    private function mailError(array $errors): string
    {
        $errors = array_values(array_filter(array_map('strval', $errors)));
        if (count($errors)) return implode("\n", array_unique($errors));

        return esc_html__('wp_mail() returned false.', 'daytidy');
    }
}