<?php

declare(strict_types=1);

namespace Abovault\Email;

use Abovault\Model\Subscription;

defined('ABSPATH') || exit;

// Data-access on the plugin's own custom tables (internal identifiers only; values are
// prepared). Direct queries + no object cache are inherent to live subscription state.
// phpcs:disable WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching, WordPress.DB.PreparedSQL.NotPrepared, WordPress.DB.PreparedSQL.InterpolatedNotPrepared, WordPress.DB.DirectDatabaseQuery.SchemaChange, PluginCheck.Security.DirectDB.UnescapedDBParameter, WordPress.NamingConventions.PrefixAllGlobals.NonPrefixedVariableFound

/**
 * Renders + sends lifecycle/retention emails. Translatable (DE/EN via WP i18n),
 * wrapped in WooCommerce's email header/footer so they look native.
 *
 * The "reliable lifecycle emails" wedge — restrict-content promised these and didn't
 * deliver; here they are first-class, sequence-driven and localized.
 */
final class LifecycleMailer
{
    /**
     * @param array<string,string> $context extra placeholders (e.g. coupon_code)
     */
    public static function send(int $subscriptionId, string $template, array $context = []): void
    {
        $sub = self::subscription($subscriptionId);
        if (!$sub) {
            return;
        }
        [$email, $name] = self::recipient($sub);
        if ($email === '') {
            return;
        }

        $tpl = self::templates()[$template] ?? null;
        if ($tpl === null) {
            return;
        }

        $vars = array_merge([
            'customer_name' => $name,
            'amount'        => self::formatAmount((float) $sub['amount'], (string) ($sub['currency'] ?? 'EUR')),
            'manage_url'    => (string) apply_filters('abovault_manage_url', self::manageUrl(), $subscriptionId),
        ], $context);

        $subject  = self::render($tpl['subject'], $vars);
        $bodyHtml = self::render($tpl['body'], $vars);
        if (!empty($tpl['cta']) && $vars['manage_url'] !== '') {
            $bodyHtml .= self::button((string) $tpl['cta'], (string) $vars['manage_url']);
        }
        $body = self::wrap($bodyHtml, $subject);

        $headers = ['Content-Type: text/html; charset=UTF-8'];

        // Brand the sender: reuse WooCommerce's configured "from" identity so lifecycle
        // emails match the store's transactional mail (not the generic "WordPress" default).
        $fromName = get_option('woocommerce_email_from_name', '');
        if (!is_string($fromName) || $fromName === '') {
            $fromName = get_bloginfo('name');
        }
        $fromEmail = get_option('woocommerce_email_from_address', '');
        if (!is_string($fromEmail) || !is_email($fromEmail)) {
            $fromEmail = get_option('admin_email');
        }
        if (is_string($fromEmail) && is_email($fromEmail)) {
            $headers[] = sprintf('From: %s <%s>', $fromName, $fromEmail);
        }

        wp_mail($email, $subject, $body, $headers);

        do_action('abovault_email_sent', $subscriptionId, $template, $email);
    }

    /**
     * Format a money amount for the email's *current* locale — not the store's fixed
     * WooCommerce number format. The email is rendered in the recipient's language
     * (switch_to_locale before send), so the amount must match: German → "19,00 €",
     * English → "€19.00", French → "1 234,50 €".
     *
     * Uses the intl extension (locale-correct grouping + symbol placement) when present,
     * with a language-based fallback for hosts without ext-intl.
     */
    private static function formatAmount(float $amount, string $currency): string
    {
        $currency = $currency !== '' ? strtoupper($currency) : 'EUR';
        $locale   = function_exists('determine_locale') ? determine_locale() : get_locale();

        // Preferred: locale-aware currency formatting (correct separators + symbol side).
        if (class_exists('\NumberFormatter')) {
            $formatter = new \NumberFormatter($locale, \NumberFormatter::CURRENCY);
            $formatted = $formatter->formatCurrency($amount, $currency);
            if (is_string($formatted) && $formatted !== '') {
                return $formatted;
            }
        }

        // Fallback without ext-intl: pick separators + symbol placement by language.
        $symbol = function_exists('get_woocommerce_currency_symbol')
            ? html_entity_decode(get_woocommerce_currency_symbol($currency), ENT_QUOTES, 'UTF-8')
            : $currency;
        $lang = strtolower(substr($locale, 0, 2));
        // Comma-decimal / symbol-after languages (EU continental) vs. English default.
        $commaDecimal = in_array($lang, ['de', 'fr', 'es', 'it', 'nl', 'pt', 'da', 'fi', 'sv', 'pl', 'cs', 'sk', 'hu', 'ro', 'el', 'bg', 'hr', 'lt', 'lv', 'sl', 'et'], true);
        if ($commaDecimal) {
            return number_format($amount, 2, ',', '.') . ' ' . $symbol;
        }
        return $symbol . number_format($amount, 2, '.', ',');
    }

    /**
     * Localized templates. English source strings; German via de_DE translation.
     *
     * @return array<string, array{subject:string, body:string}>
     */
    private static function templates(): array
    {
        $templates = [
            'dunning_1' => [
                'subject' => __('Your payment didn’t go through', 'abovault'),
                'body'    => __('Hi {customer_name},<br><br>We couldn’t collect {amount} for your subscription. We’ll try again automatically — no action needed yet. If your bank details changed, you can update them below.', 'abovault'),
                'cta'     => __('Update payment details', 'abovault'),
            ],
            'dunning_2' => [
                'subject' => __('Still can’t collect your payment', 'abovault'),
                'body'    => __('Hi {customer_name},<br><br>Your payment of {amount} is still failing. Please update your SEPA details to keep your subscription active.', 'abovault'),
                'cta'     => __('Update SEPA details', 'abovault'),
            ],
            'dunning_final' => [
                'subject' => __('Last reminder before we pause your subscription', 'abovault'),
                'body'    => __('Hi {customer_name},<br><br>This is the final reminder. If we can’t collect {amount}, your subscription will be paused. Please update your payment method now.', 'abovault'),
                'cta'     => __('Update payment method', 'abovault'),
            ],
            'renewal_reminder' => [
                'subject' => __('Your subscription renews soon', 'abovault'),
                'body'    => __('Hi {customer_name},<br><br>Your subscription ({amount}) renews in a few days via SEPA Direct Debit. Nothing to do — we’ll handle it.', 'abovault'),
                'cta'     => __('Manage subscription', 'abovault'),
            ],
            'win_back_offer' => [
                'subject' => __('Before you cancel — a little something', 'abovault'),
                'body'    => __('Hi {customer_name},<br><br>Sorry to see you thinking about leaving. You can pause instead of cancelling, or keep your benefits.', 'abovault'),
                'cta'     => __('See your options', 'abovault'),
            ],
            'win_back_1' => [
                'subject' => __('Sorry to see you go', 'abovault'),
                'body'    => __('Hi {customer_name},<br><br>Your subscription has been cancelled. You’re welcome back anytime — reactivate in a couple of clicks.', 'abovault'),
                'cta'     => __('Reactivate subscription', 'abovault'),
            ],
            'win_back_coupon' => [
                'subject' => __('Come back — here’s a discount', 'abovault'),
                'body'    => __('Hi {customer_name},<br><br>We’d love to have you back. Use code <strong>{coupon_code}</strong> for a discount on your next subscription.', 'abovault'),
                'cta'     => __('Claim your discount', 'abovault'),
            ],
            'loyalty' => [
                'subject' => __('Thank you for staying with us', 'abovault'),
                'body'    => __('Hi {customer_name},<br><br>Thanks for being a loyal subscriber! Here’s a reward: use <strong>{coupon_code}</strong> on your next order.', 'abovault'),
                'cta'     => __('View your account', 'abovault'),
            ],
        ];

        /**
         * Register additional lifecycle email templates (e.g. Abovault Pro adds extra
         * dunning / win-back touches). Each entry: ['subject'=>string,'body'=>string,'cta'?=>string].
         *
         * @param array<string, array{subject:string, body:string, cta?:string}> $templates
         */
        return (array) apply_filters('abovault_email_templates', $templates);
    }

    /**
     * Email-safe CTA button (bulletproof table layout + inline styles → renders in
     * Outlook/Gmail/Apple Mail which strip <style> and ignore many CSS properties).
     * Brand teal matches the plugin icon/banner gradient.
     */
    private static function button(string $label, string $url): string
    {
        $url   = esc_url($url);
        $label = esc_html($label);
        return '<table role="presentation" cellspacing="0" cellpadding="0" border="0" style="margin:26px 0"><tr>'
            . '<td align="center" bgcolor="#12b3a6" style="border-radius:6px;">'
            . '<a href="' . $url . '" target="_blank" rel="noopener"'
            . ' style="display:inline-block;padding:13px 30px;'
            . 'font-family:&quot;Helvetica Neue&quot;,Helvetica,Roboto,Arial,sans-serif;'
            . 'font-size:15px;font-weight:600;line-height:1;color:#ffffff;text-decoration:none;border-radius:6px;">'
            . $label . '</a></td></tr></table>';
    }

    private static function render(string $tpl, array $vars): string
    {
        foreach ($vars as $k => $v) {
            $tpl = str_replace('{' . $k . '}', (string) $v, $tpl);
        }
        return $tpl;
    }

    /**
     * Wrap in WooCommerce's email header/footer AND inline the template CSS so fonts
     * render consistently across email clients (many strip <style> blocks). The body
     * is wrapped in the WC email font so headings and text match.
     */
    private static function wrap(string $bodyHtml, string $heading): string
    {
        $font = 'font-family:"Helvetica Neue",Helvetica,Roboto,Arial,sans-serif;';
        $body = '<div style="' . $font . 'font-size:14px;line-height:1.6">' . wpautop($bodyHtml) . '</div>';

        if (function_exists('WC') && WC()->mailer()) {
            // wrap_message() applies the header/footer template; style_inline() (on a
            // WC_Email instance) inlines the template CSS → consistent fonts everywhere.
            $content = WC()->mailer()->wrap_message($heading, $body);
            if (class_exists('WC_Email')) {
                $content = (new \WC_Email())->style_inline($content);
            }
            return $content;
        }
        return '<div style="' . $font . 'max-width:600px;margin:auto">' . wpautop($bodyHtml) . '</div>';
    }

    /** @return array<string, mixed>|null */
    private static function subscription(int $id): ?array
    {
        global $wpdb;
        $row = $wpdb->get_row(
            $wpdb->prepare('SELECT * FROM ' . Subscription::table() . ' WHERE id = %d', $id),
            ARRAY_A
        );
        return $row ?: null;
    }

    /** @return array{0:string,1:string} [email, name] */
    private static function recipient(array $sub): array
    {
        $customerId = (int) ($sub['customer_id'] ?? 0);
        if ($customerId > 0 && ($user = get_userdata($customerId))) {
            return [(string) $user->user_email, (string) ($user->display_name ?: $user->user_email)];
        }
        // Guest: fall back to the order's billing details.
        $orderId = (int) ($sub['order_id'] ?? 0);
        if ($orderId > 0 && function_exists('wc_get_order') && ($order = wc_get_order($orderId))) {
            return [(string) $order->get_billing_email(), (string) $order->get_billing_first_name()];
        }
        return ['', ''];
    }

    private static function manageUrl(): string
    {
        if (function_exists('wc_get_page_permalink')) {
            $url = wc_get_page_permalink('myaccount');
            if ($url) {
                return $url;
            }
        }
        return home_url('/');
    }
}