<?php

declare(strict_types=1);

namespace Bizdex\Uplisting\Emails;

use Bizdex\Uplisting\Models\BookingDetails;

defined('ABSPATH') || exit;

/**
 * Base class for a single transactional email type.
 *
 * Handles template loading (with theme overrides), HTML rendering, and wp_mail delivery.
 * Filters run as `bizdex_uplisting_email_{name}` then `bizdex_uplisting_email_{name}_{id}`.
 *
 * @package Bizdex\Uplisting\Emails
 * @since   1.0.0
 */
abstract class AbstractEmail
{
    protected string $id = '';

    protected string $title = '';

    protected string $description = '';

    protected string $heading = '';

    protected string $subject = '';

    protected string $template = '';

    protected string $recipient = '';

    /**
     * Email type identifier slug.
     *
     * @return string
     */
    public function get_id(): string
    {
        return $this->id;
    }

    /**
     * Admin-facing email title.
     *
     * @return string
     */
    public function get_title(): string
    {
        return $this->title;
    }

    /**
     * Admin-facing email description.
     *
     * @return string
     */
    public function get_description(): string
    {
        return $this->description;
    }

    /**
     * Template path relative to the emails directory.
     *
     * @return string
     */
    public function get_template(): string
    {
        $template = $this->apply_email_filters('template', $this->template);

        return is_string($template) ? $template : $this->template;
    }

    /**
     * Whether this email type is enabled.
     *
     * Connector: emails are always on (no admin status toggle).
     *
     * @return bool
     */
    public function is_enabled(): bool
    {
        return (bool) apply_filters('bizdex_uplisting_email_enabled', true, $this);
    }

    /**
     * Resolved subject line with placeholders replaced.
     *
     * @param array<string, mixed> $data Template data for placeholders.
     * @return string
     */
    public function get_subject(array $data = []): string
    {
        $subject = $this->replace_placeholders($this->get_setting('subject', $this->subject), $data);
        $subject = $this->apply_email_filters('subject', $subject, $data);

        return is_string($subject) ? $subject : '';
    }

    /**
     * Resolved heading with placeholders replaced.
     *
     * @param array<string, mixed> $data Template data for placeholders.
     * @return string
     */
    public function get_heading(array $data = []): string
    {
        $heading = $this->replace_placeholders($this->get_setting('heading', $this->heading), $data);
        $heading = $this->apply_email_filters('heading', $heading, $data);

        return is_string($heading) ? $heading : '';
    }

    /**
     * Resolved additional body content with placeholders replaced.
     *
     * @param array<string, mixed> $data Template data for placeholders.
     * @return string
     */
    public function get_additional_content(array $data = []): string
    {
        $content = $this->replace_placeholders($this->get_setting('additional_content', ''), $data);
        $content = $this->apply_email_filters('additional_content', $content, $data);

        return is_string($content) ? $content : '';
    }

    /**
     * Default subject before admin overrides.
     *
     * @return string
     */
    public function get_default_subject(): string
    {
        return $this->subject;
    }

    /**
     * Default heading before admin overrides.
     *
     * @return string
     */
    public function get_default_heading(): string
    {
        return $this->heading;
    }

    /**
     * Resolve the primary recipient address for a booking.
     *
     * @param BookingDetails $booking Booking model.
     * @return string
     */
    abstract public function get_recipient(BookingDetails $booking): string;

    /**
     * Recipient address after email-specific filters.
     *
     * @param BookingDetails $booking Booking model.
     * @return string
     */
    public function get_recipient_filtered(BookingDetails $booking): string
    {
        $recipient = $this->apply_email_filters('recipient', $this->get_recipient($booking), $booking);

        return is_string($recipient) ? $recipient : '';
    }

    /**
     * Template variables passed to email partials.
     *
     * @param BookingDetails $booking Booking model.
     * @return array<string, mixed>
     */
    public function get_template_args(BookingDetails $booking): array
    {
        $data = function_exists('bizdex_uplisting_get_booking_data')
            ? bizdex_uplisting_get_booking_data($booking->get_id())
            : [];

        if (!is_array($data)) {
            $data = [];
        }

        $data['email_heading']      = $this->get_heading($data);
        $data['additional_content'] = $this->get_additional_content($data);
        $data['email_id']           = $this->id;

        $data = $this->apply_email_filters('template_args', $data, $booking);

        return is_array($data) ? $data : [];
    }

    /**
     * Render full HTML email body (header, template, footer).
     *
     * @param array<string, mixed> $args Template variables.
     * @return string
     */
    public function get_content(array $args = []): string
    {
        $args['email_heading']      = $args['email_heading'] ?? $this->get_heading($args);
        $args['additional_content'] = $args['additional_content'] ?? $this->get_additional_content($args);

        do_action('bizdex_uplisting_before_email_content', $args, $this);

        $content = $this->get_template_html('layouts/header', $args)
            . $this->get_template_html($this->get_template(), $args)
            . $this->get_template_html('layouts/footer', $args);

        $content = $this->apply_email_filters('content', $content, $args);

        do_action('bizdex_uplisting_after_email_content', $content, $args, $this);

        return is_string($content) ? $content : '';
    }

    /**
     * Send the email for a booking when enabled and recipient is valid.
     *
     * @param BookingDetails $booking Booking model.
     * @return bool True when wp_mail accepts the message.
     */
    public function send(BookingDetails $booking): bool
    {
        if (!$this->is_enabled()) {
            return false;
        }

        if (!(bool) apply_filters('bizdex_uplisting_email_should_send', true, $booking, $this)) {
            return false;
        }

        $to = $this->get_recipient_filtered($booking);
        if ($to === '' || !is_email($to)) {
            do_action('bizdex_uplisting_email_invalid_recipient', $booking, $this);

            return false;
        }

        $args    = $this->get_template_args($booking);
        $subject = $this->get_subject($args);
        $message = $this->get_content($args);

        $headers = apply_filters('bizdex_uplisting_email_headers', [], $this->id, $booking->get_id(), $this);
        $headers = apply_filters('bizdex_uplisting_email_headers_' . $this->id, is_array($headers) ? $headers : [], $booking->get_id(), $this);
        if (!is_array($headers)) {
            $headers = [];
        }

        $attachments = $this->apply_email_filters('attachments', [], $booking);
        if (!is_array($attachments)) {
            $attachments = [];
        }

        do_action('bizdex_uplisting_before_email_send', $to, $subject, $message, $headers, $attachments, $booking, $this);

        $sent = $this->mail($to, $subject, $message, $headers, $attachments);

        do_action('bizdex_uplisting_after_email_send', $sent, $to, $subject, $message, $headers, $attachments, $booking, $this);

        if ($sent) {
            do_action('bizdex_uplisting_email_sent', $to, $booking, $this);
            do_action('bizdex_uplisting_email_sent_' . $this->id, $to, $booking, $this);
        } else {
            do_action('bizdex_uplisting_email_failed', $to, $booking, $this);
            do_action('bizdex_uplisting_email_failed_' . $this->id, $to, $booking, $this);
        }

        return $sent;
    }

    /**
     * Deliver HTML mail via wp_mail with default From headers.
     *
     * @param string               $to          Recipient address.
     * @param string               $subject     Email subject.
     * @param string               $message     HTML body.
     * @param array<int, string>   $headers     Extra headers.
     * @param array<int, string>   $attachments Attachment paths.
     * @return bool
     */
    public function mail(string $to, string $subject, string $message, array $headers = [], array $attachments = []): bool
    {
        if ($to === '' || !is_email($to)) {
            return false;
        }

        $from_name  = (string) get_option('bizdex_uplisting_booking_from_name', get_bloginfo('name'));
        $from_email = (string) get_option('bizdex_uplisting_booking_from_email', get_option('admin_email'));

        if ($from_name === '') {
            $from_name = (string) get_bloginfo('name');
        }
        if ($from_email === '' || !is_email($from_email)) {
            $from_email = (string) get_option('admin_email');
        }

        $from_name  = (string) apply_filters('bizdex_uplisting_email_from_name', $from_name, $this);
        $from_email = (string) apply_filters('bizdex_uplisting_email_from_address', $from_email, $this);

        $default_headers = [
            'Content-Type: text/html; charset=UTF-8',
            'From: ' . $from_name . ' <' . $from_email . '>',
        ];

        $headers = array_values(array_filter(array_merge($default_headers, $headers)));
        $headers = apply_filters('bizdex_uplisting_email_mail_headers', $headers, $to, $subject, $this);
        if (!is_array($headers)) {
            $headers = $default_headers;
        }

        $message = (string) apply_filters('bizdex_uplisting_email_mail_message', $message, $to, $subject, $this);

        return (bool) wp_mail($to, $subject, $message, $headers, $attachments);
    }

    /**
     * Render a single email template partial to HTML.
     *
     * @param string               $template Partial path without extension.
     * @param array<string, mixed> $args     Variables for the partial.
     * @return string
     */
    protected function get_template_html(string $template, array $args = []): string
    {
        $args = apply_filters('bizdex_uplisting_email_partial_args', $args, $template, $this);
        if (!is_array($args)) {
            $args = [];
        }

        $path = $this->locate_template($template);
        if ($path === '') {
            return '';
        }

        $view_args = $args;

        ob_start();
        do_action('bizdex_uplisting_before_email_template', $template, $path, $args, $this);
        include $path;
        do_action('bizdex_uplisting_after_email_template', $template, $path, $args, $this);
        $html = (string) ob_get_clean();

        return (string) apply_filters('bizdex_uplisting_email_partial_html', $html, $template, $args, $this);
    }

    /**
     * Resolve template file path (theme override or plugin default).
     *
     * @param string $template Partial path without extension.
     * @return string Absolute path, or empty when not found.
     */
    protected function locate_template(string $template): string
    {
        $template = ltrim(str_replace(['..', '\\'], ['', '/'], $template), '/');
        $relative = 'emails/' . $template . '.php';

        $theme = (string) locate_template([
            'bizdex-uplisting/' . $relative,
            'wp-uplisting-connector/' . $relative,
        ]);

        if ($theme !== '' && is_readable($theme)) {
            $path = $theme;
        } else {
            $plugin = BIZDEX_UPLISTING_PLUGIN_DIR . 'templates/' . $relative;
            $path   = is_readable($plugin) ? $plugin : '';
        }

        $path = apply_filters('bizdex_uplisting_email_locate_template', $path, $template, $this);

        return is_string($path) ? $path : '';
    }

    /**
     * WordPress option key for an email setting field.
     *
     * @param string $field Setting field name (e.g. subject, enabled).
     * @return string
     */
    public function option_key(string $field): string
    {
        return 'bizdex_uplisting_email_' . $this->id . '_' . $field;
    }

    /**
     * Stored setting value, falling back to default when missing or blank.
     *
     * @param string $field   Setting field name.
     * @param string $default Fallback when unset or blank.
     * @return string
     */
    public function get_setting(string $field, string $default = ''): string
    {
        $value = get_option($this->option_key($field), null);

        if (!is_string($value) || trim($value) === '') {
            return $default;
        }

        return $value;
    }

    /**
     * Apply global then per-email-id filters: `bizdex_uplisting_email_{$name}` and `_{$name}_{$id}`.
     *
     * @param mixed $value
     * @param mixed ...$args Extra args between value and $this.
     * @return mixed
     */
    protected function apply_email_filters(string $name, $value, ...$args)
    {
        $value = apply_filters("bizdex_uplisting_email_{$name}", $value, ...[...$args, $this]);
        $value = apply_filters("bizdex_uplisting_email_{$name}_{$this->id}", $value, ...[...$args, $this]);

        return $value;
    }

    /**
     * Replace `{key}` placeholders in text with scalar values from data.
     *
     * @param string               $text Source text.
     * @param array<string, mixed> $data Replacement values.
     * @return string
     */
    protected function replace_placeholders(string $text, array $data): string
    {
        if ($text === '' || $data === []) {
            return $text;
        }

        $replacements = [];
        foreach ($data as $key => $value) {
            if (!is_scalar($value) && $value !== null) {
                continue;
            }
            $replacements['{' . $key . '}'] = (string) $value;
        }

        $replacements = apply_filters('bizdex_uplisting_email_placeholders', $replacements, $data, $this);
        if (!is_array($replacements)) {
            return $text;
        }

        return str_replace(array_keys($replacements), array_values($replacements), $text);
    }
}