' . $heading . '

<?php
/**
 * Email notification rendering and delivery.
 *
 * @package Abientot
 */

namespace Abientot\Notifications;

use Abientot\Support\MultilingualText;
use Abientot\Admin\Settings;
use Abientot\Repositories\AppointmentsRepository;
use Abientot\Repositories\LocationsRepository;
use Abientot\Support\DateTimeHelper;
use DateTimeImmutable;
use DateTimeZone;
use Exception;
use WP_Error;

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

final class EmailService {
	private ?string $transport_result = null;
	/** Actual outcome from this sender instance, independent of optional audit observers. */
	public function last_transport_result(): ?string {
		return $this->transport_result;
	}
	private AppointmentsRepository $appointments;
	private LocationsRepository $locations;

	public function __construct() {
		$this->appointments = new AppointmentsRepository();
		$this->locations    = new LocationsRepository();
	}

	/**
	 * @return array<string,string>
	 */
	public static function template_labels(): array {
		return array(
			'customer_confirmation' => __( 'Customer confirmation', 'abientot' ),
			'customer_confirmed'    => __( 'Customer booking confirmed', 'abientot' ),
			'admin_new_booking'     => __( 'Admin new booking', 'abientot' ),
			'customer_cancellation' => __( 'Customer cancellation', 'abientot' ),
			'customer_rescheduling' => __( 'Customer rescheduling', 'abientot' ),
			'customer_completed'    => __( 'Customer completed booking', 'abientot' ),
		);
	}

	/**
	 * @return array<string,string>
	 */
	public static function template_subject_defaults(): array {
		return array(
			'customer_confirmation' => __( 'Your booking with {business_name}', 'abientot' ),
			'customer_confirmed'    => __( 'Your booking is confirmed', 'abientot' ),
			'admin_new_booking'     => __( 'New booking: {service_name} with {customer_name}', 'abientot' ),
			'customer_cancellation' => __( 'Your booking has been cancelled', 'abientot' ),
			'customer_rescheduling' => __( 'Your booking has been rescheduled', 'abientot' ),
			'customer_completed'    => __( 'Thank you for your booking', 'abientot' ),
		);
	}

	/**
	 * @return array<string,string>
	 */
	public static function template_body_defaults(): array {
		return array(
			'customer_confirmation' => self::html_template(
				__( 'Booking request received', 'abientot' ),
				'<p style="margin:0 0 18px;">' . __( 'Hello {customer_name},', 'abientot' ) . '</p><p style="margin:0 0 20px;">' . __( 'Thank you for your booking request. Here are the details we received:', 'abientot' ) . '</p>' . self::details_table(
					array(
						__( 'Service', 'abientot' )  => '{service_name}',
						__( 'When', 'abientot' )     => '{start}',
						__( 'Location', 'abientot' ) => '{location_name}',
						__( 'Status', 'abientot' )   => '{status}'
					)
				) . '<div style="margin-top:22px;color:#4b5563;font-size:14px;line-height:1.6;"><p style="margin:0 0 8px;">{cancellation_contact}</p><p style="margin:0;">{rescheduling_contact}</p></div>'
			),
			'customer_confirmed'    => self::html_template(
				__( 'Booking confirmed', 'abientot' ),
				'<p style="margin:0 0 18px;">' . __( 'Hello {customer_name},', 'abientot' ) . '</p><p style="margin:0 0 20px;">' . __( 'Your booking has been confirmed. We look forward to seeing you.', 'abientot' ) . '</p>' . self::details_table(
					array(
						__( 'Service', 'abientot' )  => '{service_name}',
						__( 'When', 'abientot' )     => '{start}',
						__( 'Location', 'abientot' ) => '{location_name}',
						__( 'Status', 'abientot' )   => '{status}'
					)
				) . '<div style="margin-top:22px;color:#4b5563;font-size:14px;line-height:1.6;"><p style="margin:0 0 8px;">{cancellation_contact}</p><p style="margin:0;">{rescheduling_contact}</p></div>'
			),
			'admin_new_booking'     => self::html_template(
				__( 'New booking received', 'abientot' ),
				'<p style="margin:0 0 20px;">' . __( 'A new booking has been created.', 'abientot' ) . '</p>' . self::details_table(
					array(
						__( 'Customer', 'abientot' )   => '{customer_name}',
						__( 'Email', 'abientot' )      => '{customer_email}',
						__( 'Phone', 'abientot' )      => '{customer_phone}',
						__( 'Service', 'abientot' )    => '{service_name}',
						__( 'When', 'abientot' )       => '{start}',
						__( 'Status', 'abientot' )     => '{status}',
						__( 'Payment', 'abientot' )    => '{payment_status}',
						__( 'Booking ID', 'abientot' ) => '{booking_id}'
					)
				)
			),
			'customer_cancellation' => self::html_template(
				__( 'Booking cancelled', 'abientot' ),
				'<p style="margin:0 0 18px;">' . __( 'Hello {customer_name},', 'abientot' ) . '</p><p style="margin:0 0 20px;">' . __( 'Your booking has been cancelled.', 'abientot' ) . '</p>' . self::details_table(
					array(
						__( 'Service', 'abientot' )  => '{service_name}',
						__( 'When', 'abientot' )     => '{start}',
						__( 'Location', 'abientot' ) => '{location_name}'
					)
				)
			),
			'customer_rescheduling' => self::html_template(
				__( 'Booking rescheduled', 'abientot' ),
				'<p style="margin:0 0 18px;">' . __( 'Hello {customer_name},', 'abientot' ) . '</p><p style="margin:0 0 20px;">' . __( 'Your booking has been rescheduled. Your updated details are below.', 'abientot' ) . '</p>' . self::details_table(
					array(
						__( 'Service', 'abientot' )  => '{service_name}',
						__( 'New time', 'abientot' ) => '{start}',
						__( 'Location', 'abientot' ) => '{location_name}'
					)
				)
			),
			'customer_completed'    => self::html_template(
				__( 'Thank you for your visit', 'abientot' ),
				'<p style="margin:0 0 18px;">' . __( 'Hello {customer_name},', 'abientot' ) . '</p><p style="margin:0 0 20px;">' . __( 'Thank you for visiting {business_name}. We hope to see you again.', 'abientot' ) . '</p>' . self::details_table(
					array(
						__( 'Service', 'abientot' ) => '{service_name}',
						__( 'When', 'abientot' )    => '{start}'
					)
				)
			),
		);
	}

	/**
	 * Previous plain-text defaults used to upgrade only untouched saved templates.
	 *
	 * @return array<string,string>
	 */
	public static function legacy_template_body_defaults(): array {
		return array(
			'customer_confirmation' => "Hello {customer_name},\n\nYour booking request has been received.\n\nService: {service_name}\nWhen: {start}\nLocation: {location_name}\n\n{cancellation_contact}\n{rescheduling_contact}\n\nThank you,\n{business_name}",
			'customer_confirmed'    => "Hello {customer_name},\n\nYour booking has been confirmed.\n\nService: {service_name}\nWhen: {start}\nLocation: {location_name}\n\n{cancellation_contact}\n{rescheduling_contact}\n\nThank you,\n{business_name}",
			'admin_new_booking'     => "A new booking has been created.\n\nCustomer: {customer_name}\nEmail: {customer_email}\nPhone: {customer_phone}\nService: {service_name}\nWhen: {start}\nStatus: {status}\nPayment: {payment_status}\n\nBooking ID: {booking_id}",
			'customer_cancellation' => "Hello {customer_name},\n\nYour booking has been cancelled.\n\nService: {service_name}\nWhen: {start}\n\n{business_name}",
			'customer_rescheduling' => "Hello {customer_name},\n\nYour booking has been rescheduled.\n\nService: {service_name}\nNew time: {start}\nLocation: {location_name}\n\n{business_name}",
			'customer_completed'    => "Hello {customer_name},\n\nThank you for visiting {business_name}.\n\nService: {service_name}\nWhen: {start}",
		);
	}

	/**
	 * True when two saved templates are the same markup. Saving the email settings unchanged
	 * lets the editor reorder attributes, respace styles, add <tbody> and line breaks; such a
	 * template is still the plugin default.
	 */
	public static function same_template( string $a, string $b ): bool {
		if ( $a === $b ) {
			return true;
		}
		// The 1.0.x credit line is never sent as saved (see with_credit()), so it doesn't count.
		$canonical = self::canonical_template( self::without_saved_credit( $a ) );
		return null !== $canonical && $canonical === self::canonical_template( self::without_saved_credit( $b ) );
	}

	private static function canonical_template( string $html ): ?string {
		if ( ! class_exists( '\DOMDocument' ) ) {
			return null;
		}
		$document = new \DOMDocument();
		$previous = libxml_use_internal_errors( true );
		$loaded   = $document->loadHTML( '<?xml encoding="utf-8"?><div>' . $html . '</div>', LIBXML_NONET );
		libxml_clear_errors();
		libxml_use_internal_errors( $previous );
		$root = $loaded ? $document->getElementsByTagName( 'div' )->item( 0 ) : null;
		return $root ? self::canonical_node( $root ) : null;
	}

	private static function canonical_node( \DOMNode $node ): string {
		if ( XML_TEXT_NODE === $node->nodeType ) {
			return trim( (string) preg_replace( '/[\s\x{00A0}]+/u', ' ', (string) $node->nodeValue ) );
		}
		if ( XML_ELEMENT_NODE !== $node->nodeType ) {
			return '';
		}
		$children = '';
		foreach ( $node->childNodes as $child ) {
			$part      = self::canonical_node( $child );
			$children .= '' === $part ? '' : $part . "\n";
		}
		$tag = strtolower( $node->nodeName );
		if ( 'tbody' === $tag ) {
			return rtrim( $children );
		}
		$attributes = array();
		foreach ( $node->attributes as $attribute ) {
			$name                = strtolower( $attribute->name );
			$attributes[ $name ] = 'style' === $name ? self::canonical_style( $attribute->value ) : trim( $attribute->value );
		}
		ksort( $attributes );
		return '<' . $tag . ' ' . wp_json_encode( $attributes ) . ">\n" . $children . '</' . $tag . '>';
	}

	private static function canonical_style( string $style ): string {
		$rules = array();
		foreach ( explode( ';', $style ) as $rule ) {
			$pair = explode( ':', $rule, 2 );
			if ( 2 === count( $pair ) && '' !== trim( $pair[0] ) ) {
				$rules[] = strtolower( trim( $pair[0] ) ) . ':' . preg_replace( '/\s+/', ' ', trim( $pair[1] ) );
			}
		}
		return implode( ';', $rules );
	}

	private static function html_template( string $heading, string $content ): string {
		return '<div style="margin:0;padding:28px 16px;background:#f5f7fa;color:#1f2937;font-family:Arial,sans-serif;line-height:1.5;"><div style="max-width:620px;margin:0 auto;background:#ffffff;border:1px solid #e5e7eb;border-radius:8px;overflow:hidden;"><div style="padding:26px 30px;border-bottom:1px solid #e5e7eb;"><div style="margin:0 0 6px;color:#6b7280;font-size:13px;font-weight:600;letter-spacing:.04em;text-transform:uppercase;">{business_name}</div><h1 style="margin:0;color:#111827;font-size:22px;line-height:1.3;">' . $heading . '</h1></div><div style="padding:28px 30px;font-size:15px;">' . $content . '</div></div></div>';
	}

	/**
	 * @param array<string,string> $rows Detail labels and values.
	 */
	private static function details_table( array $rows ): string {
		$html = '<table role="presentation" style="width:100%;border-collapse:collapse;border:1px solid #e5e7eb;border-radius:6px;">';
		foreach ( $rows as $label => $value ) {
			$html .= '<tr><td style="width:32%;padding:10px 12px;border-bottom:1px solid #eef0f2;color:#6b7280;font-size:13px;vertical-align:top;">' . $label . '</td><td style="padding:10px 12px;border-bottom:1px solid #eef0f2;color:#111827;font-weight:600;vertical-align:top;">' . $value . '</td></tr>';
		}

		return $html . '</table>';
	}

	/**
	 * Sends customer and admin creation notifications for a booking.
	 */
	public function send_booking_created( int $appointment_id ): void {
		$this->send_template_for_booking( 'customer_confirmation', $appointment_id );
		$this->send_template_for_booking( 'admin_new_booking', $appointment_id );
	}

	/**
	 * Sends the customer notification matching a booking lifecycle event.
	 */
	public function send_booking_event( int $appointment_id, string $event, string $body_override = '' ): void {
		$map = array(
			'confirmed'   => 'customer_confirmed',
			'cancelled'   => 'customer_cancellation',
			'rescheduled' => 'customer_rescheduling',
			'completed'   => 'customer_completed',
		);

		if ( isset( $map[ $event ] ) ) {
			$this->send_template_for_booking( $map[ $event ], $appointment_id, $body_override );
		}
	}

	/**
	 * Returns the customer notification preview for a booking event.
	 *
	 * @return array{subject:string,body:string}
	 */
	public function preview_booking_event( int $appointment_id, string $event, string $start_utc = '', string $end_utc = '', string $body_override = '' ): array {
		$map = array(
			'confirmed'   => 'customer_confirmed',
			'cancelled'   => 'customer_cancellation',
			'rescheduled' => 'customer_rescheduling',
			'completed'   => 'customer_completed',
		);

		if ( ! isset( $map[ $event ] ) ) {
			return array(
				'subject' => '',
				'body'    => ''
			);
		}

		$booking = $this->appointments->find_for_admin( $appointment_id );
		if ( ! $booking ) {
			return array(
				'subject' => '',
				'body'    => ''
			);
		}

		if ( '' !== $start_utc ) {
			$booking['start_utc'] = $start_utc;
		}
		if ( '' !== $end_utc ) {
			$booking['end_utc'] = $end_utc;
		}

		$template_key = $map[ $event ];
		$variables    = $this->variables_for_booking( $booking );
		$body         = '' !== $body_override ? $body_override : (string) $this->setting( 'email_' . $template_key . '_body' );

		return array(
			'subject' => $this->render_template( $this->setting( 'email_' . $template_key . '_subject' ), $variables ),
			'body'    => (string) apply_filters( 'abientot_email_booking_body', $this->render_template( $body, $variables ), $booking, $template_key ),
		);
	}

	/**
	 * Returns a rendered preview for settings UI.
	 *
	 * @return array{subject:string,body:string}
	 */
	public function preview( string $template_key, int $appointment_id = 0 ): array {
		$booking   = $appointment_id > 0 ? $this->appointments->find_for_admin( $appointment_id ) : null;
		$variables = $booking ? $this->variables_for_booking( $booking ) : $this->sample_variables();

		return array(
			'subject' => $this->render_template( $this->setting( 'email_' . $template_key . '_subject' ), $variables ),
			'body'    => $this->render_template( $this->setting( 'email_' . $template_key . '_body' ), $variables ),
		);
	}

	/**
	 * Sends a sample test email.
	 */
	public function send_test( string $template_key, string $recipient, int $appointment_id = 0, ?string $subject_override = null, ?string $body_override = null ) {
		if ( ! is_email( $recipient ) || ! isset( self::template_labels()[ $template_key ] ) ) {
			return new WP_Error( 'abientot_test_email_invalid', __( 'Choose a valid template and recipient.', 'abientot' ) );
		}

		$preview = $this->preview( $template_key, $appointment_id );
		if ( null !== $subject_override || null !== $body_override ) {
			$booking   = $appointment_id > 0 ? $this->appointments->find_for_admin( $appointment_id ) : null;
			$variables = $booking ? $this->variables_for_booking( $booking ) : $this->sample_variables();
			if ( null !== $subject_override ) {
				$preview['subject'] = $this->render_template( $subject_override, $variables );
			}
			if ( null !== $body_override ) {
				$preview['body'] = $this->render_template( $body_override, $variables );
			}
		}
		$sent = $this->send(
			$recipient,
			sprintf(
				/* translators: %s: email subject. */
				__( '[Test] %s', 'abientot' ),
				$preview['subject']
			),
			$preview['body'],
			array(
				'appointment_id' => $appointment_id,
				'template'       => 'test',
				'recipient_role' => 'test'
			)
		);

		return $sent ? true : new WP_Error( 'abientot_test_email_failed', __( 'WordPress could not send the test email.', 'abientot' ) );
	}

	/**
	 * Returns safe sample values for live admin template previews.
	 *
	 * @return array<string,string>
	 */
	public function sample_template_variables(): array {
		return $this->sample_variables();
	}

	/** Sends an explicitly authorized custom customer template; transport exceptions remain observable. */
	public function send_custom_booking( int $appointment_id, string $subject, string $body, array $context = array() ): bool {
		$this->transport_result = null;
		$booking                = $this->appointments->find_for_admin( $appointment_id );
		if ( ! $booking || ! is_email( (string) $booking['customer_email'] ) ) {
			return false;
		}
		// Customer messages use the language the visitor booked in (WPML/Polylang); the text itself is the
		// caller's, except the reminder template, which is translated like the booking emails.
		$reminder_defaults = 'reminder' === ( $context['template'] ?? '' ) ? \Abientot\Reminders\Settings::defaults() : null;
		return (bool) MultilingualText::for_booking(
			$booking,
			function () use ( $booking, $appointment_id, $subject, $body, $context, $reminder_defaults ): bool {
				$booking      = $this->booking_in_language( $booking, $appointment_id );
				$variables    = $this->variables_for_booking( $booking );
				$template     = in_array( $context['template'] ?? '', array( 'custom', 'reminder', 'service_preparation', 'service_followup' ), true ) ? $context['template'] : 'custom';
				$rendered     = ( $context['rendered'] ?? false ) === true;
				if ( null !== $reminder_defaults && ! $rendered && MultilingualText::forced() ) {
					$localized = \Abientot\Reminders\Settings::defaults();
					$subject   = $subject === $reminder_defaults['subject'] ? $localized['subject'] : MultilingualText::translate( $subject, 'reminder-subject' );
					$body      = $body === $reminder_defaults['body'] ? $localized['body'] : MultilingualText::translate( $body, 'reminder-body' );
				}
				$renderedBody = $rendered ? $body : $this->render_template( $body, $variables );
				if ( $template === 'reminder' ) {
					$renderedBody = (string) apply_filters( 'abientot_email_booking_body', $renderedBody, $booking, $template );
				}
				return $this->send(
					(string) $booking['customer_email'],
					$rendered ? $subject : $this->render_template( $subject, $variables ),
					$renderedBody,
					array(
						'appointment_id' => $appointment_id,
						'template'       => $template,
						'recipient_role' => 'customer'
					)
				);
			}
		);
	}

	/**
	 * Re-reads the booking while a booking language is forced, so the status name follows that
	 * language; otherwise returns it unchanged.
	 *
	 * @param array<string,mixed> $booking Booking row.
	 * @return array<string,mixed>
	 */
	private function booking_in_language( array $booking, int $appointment_id ): array {
		if ( ! MultilingualText::forced() ) {
			return $booking;
		}
		$fresh = $this->appointments->find_for_admin( $appointment_id );
		$fresh = is_array( $fresh ) ? $fresh : $booking;
		if ( isset( $fresh['status_label'] ) ) {
			$fresh['status_label'] = MultilingualText::status_label( (string) ( $fresh['status_slug'] ?? '' ), (string) $fresh['status_label'] );
		}
		return $fresh;
	}

	/**
	 * Template text for a customer email in the booking's language: a text left at the plugin
	 * default is the default in that language; a text the business wrote is its WPML/Polylang
	 * translation (string "email-<template>-subject|body"), or the text itself.
	 */
	private function customer_template_text( string $template_key, string $part, string $stored, ?string $site_default ): string {
		if ( ! MultilingualText::forced() ) {
			return $stored;
		}
		if ( null !== $site_default && self::same_template( $stored, $site_default ) ) {
			$defaults = 'subject' === $part ? self::template_subject_defaults() : self::template_body_defaults();
			return (string) ( $defaults[ $template_key ] ?? $stored );
		}
		return MultilingualText::translate( $stored, 'email-' . $template_key . '-' . $part );
	}

	private function send_template_for_booking( string $template_key, int $appointment_id, string $body_override = '' ): void {
		try {
			$this->deliver_template_for_booking( $template_key, $appointment_id, $body_override );
		} catch ( \Throwable $exception ) {
			// A transport/filter failure must never invite a duplicate booking retry.
			( new \Abientot\Repositories\ActivityLogRepository() )->record_booking_event( $appointment_id, 'notification_failed', __( 'The booking was saved, but its notification could not be sent.', 'abientot' ), array( 'template' => $template_key ) );
		}
	}

	/** Explicit manager callers authorize and acknowledge duplicate risk before invoking this. */
	public function resend_booking_template( int $appointment_id, string $template_key ): bool {
		if ( \Abientot\Repositories\BookingLock::is_held() || ! isset( self::template_labels()[ $template_key ] ) ) {
			return false;
		}
		\Abientot\Support\TransactionGuard::prepare_write();
		return $this->deliver_template_for_booking( $template_key, $appointment_id, '', true );
	}

	private function deliver_template_for_booking( string $template_key, int $appointment_id, string $body_override = '', bool $retry = false ): bool {
		$settings = Settings::values();
		if ( empty( $settings[ 'email_' . $template_key . '_enabled' ] ) ) {
			return false;
		}

		$booking = $this->appointments->find_for_admin( $appointment_id );
		if ( ! $booking || ( $retry && ! is_email( (string) ( $booking['customer_email'] ?? '' ) ) ) ) {
			return false;
		}

		$recipient = 'admin_new_booking' === $template_key ? (string) $settings['admin_notification_email'] : (string) $booking['customer_email'];
		if ( ! is_email( $recipient ) ) {
			return false;
		}

		$subject_text = (string) $settings[ 'email_' . $template_key . '_subject' ];
		$body_text    = (string) $settings[ 'email_' . $template_key . '_body' ];
		$build        = function ( array $booking, string $subject_text, string $body_text ) use ( $template_key, $body_override, $recipient, $appointment_id ): void {
			$variables = $this->variables_for_booking( $booking );
			$subject   = $this->render_template( $subject_text, $variables );
			$body      = $this->render_template( '' !== $body_override ? $body_override : $body_text, $variables );

			$body = (string) apply_filters( 'abientot_email_booking_body', $body, $booking, $template_key );
			if ( ! $this->send(
				$recipient,
				$subject,
				$body,
				array(
					'appointment_id' => $appointment_id,
					'template'       => $template_key,
					'recipient_role' => 'admin_new_booking' === $template_key ? 'admin' : 'customer'
				)
			) ) {
				throw new Exception( 'Delivery failed.' );
			}
		};
		if ( ! in_array( $template_key, MultilingualText::CUSTOMER_EMAILS, true ) ) {
			$build( $booking, $subject_text, $body_text );
			return true;
		}
		// The customer reads it in the language they booked in; defaults are compared in the site language.
		$subject_default = self::template_subject_defaults()[ $template_key ] ?? null;
		$body_default    = self::template_body_defaults()[ $template_key ] ?? null;
		MultilingualText::for_booking(
			$booking,
			function () use ( $build, $booking, $appointment_id, $template_key, $subject_text, $body_text, $subject_default, $body_default ): void {
				$build(
					$this->booking_in_language( $booking, $appointment_id ),
					$this->customer_template_text( $template_key, 'subject', $subject_text, $subject_default ),
					$this->customer_template_text( $template_key, 'body', $body_text, $body_default )
				);
			}
		);
		return true;
	}

	private function send( string $recipient, string $subject, string $body, array $context = array() ): bool {
		$settings = Settings::values();
		$from     = is_email( (string) $settings['email_from_address'] ) ? (string) $settings['email_from_address'] : (string) get_option( 'admin_email' );
		$name     = '' !== trim( (string) $settings['email_from_name'] ) ? (string) $settings['email_from_name'] : (string) get_bloginfo( 'name' );
		$reply_to = is_email( (string) $settings['email_reply_to_address'] ) ? (string) $settings['email_reply_to_address'] : $from;
		$headers  = array(
			'Content-Type: text/html; charset=UTF-8',
			'From: ' . $this->clean_header_value( $name ) . ' <' . $from . '>',
			'Reply-To: ' . $reply_to,
		);
		$email    = array(
			'to'      => $recipient,
			'subject' => $this->plain_text( $subject ),
			'body'    => $this->with_credit( $this->html_body( $body ) ),
			'headers' => $headers,
		);

		$attempt = array(
			'attempt_uuid'     => wp_generate_uuid4(),
			'appointment_id'   => max( 0, (int) ( $context['appointment_id'] ?? 0 ) ),
			'template'         => (string) ( $context['template'] ?? 'custom' ),
			'recipient_role'   => (string) ( $context['recipient_role'] ?? 'customer' ),
			'content_revision' => hash_hmac( 'sha256', wp_json_encode( array( $email['subject'], $email['body'] ) ), wp_salt( 'auth' ) ),
			'occurred_at'      => gmdate( 'Y-m-d H:i:s' ),
		);
		try {
			$email = apply_filters( 'abientot_before_email_sent', $email );
			if ( false === $email || ! is_array( $email ) ) {
				$this->observe_attempt( $attempt, 'suppressed' );
				return false;
			}
			$attempt['content_revision'] = hash_hmac( 'sha256', wp_json_encode( array( $email['subject'], $email['body'] ) ), wp_salt( 'auth' ) );
			$sent                        = wp_mail( (string) $email['to'], (string) $email['subject'], (string) $email['body'], (array) $email['headers'] );
			$this->observe_attempt( $attempt, $sent ? 'accepted' : 'rejected' );
			return $sent;
		} catch ( \Throwable $error ) {
			$this->observe_attempt( $attempt, 'exception' );
			throw $error;
		}
	}

	/** Observational only: no listener may alter the transport or saved booking result. */
	private function observe_attempt( array $attempt, string $result ): void {
		$this->transport_result = $result;
		global $wpdb;
		$suppressed = $wpdb->suppress_errors( true );
		try {
			do_action( 'abientot_email_attempt', array_merge( $attempt, array( 'result' => $result ) ) );
		} catch ( \Throwable $error ) {
			/* The attempt log is best effort, not a durable send intent. */
		} finally {
				$wpdb->suppress_errors( $suppressed );
		}
	}

	/**
	 * @param array<string,mixed> $booking Joined booking row.
	 * @return array<string,string>
	 */
	public function variables_for_booking( array $booking ): array {
		$settings  = Settings::values();
		$variables = array(
			'business_name'        => (string) $settings['business_name'],
			'booking_id'           => (string) $booking['id'],
			'customer_name'        => (string) $booking['customer_name'],
			'customer_email'       => (string) $booking['customer_email'],
			'customer_phone'       => (string) $booking['customer_phone'],
			'service_name'         => (string) $booking['service_name'],
			'staff_name'           => (string) $booking['staff_name'],
			'location_name'        => (string) $booking['location_name'],
			'status'               => (string) $booking['status_label'],
			'start'                => $this->format_booking_time( (string) $booking['start_utc'], (string) $booking['timezone'] ),
			'end'                  => $this->format_booking_time( (string) $booking['end_utc'], (string) $booking['timezone'] ),
			'price'                => \Abientot\Support\Currency::format( (int) $booking['price_cents'], $booking['currency'] ),
			'currency'             => strtoupper( (string) $booking['currency'] ),
			'payment_status'       => ucwords( str_replace( '_', ' ', (string) $booking['payment_status'] ) ),
			'customer_note'        => (string) $booking['customer_note'],
			'site_name'            => (string) get_bloginfo( 'name' ),
			'site_url'             => home_url( '/' ),
			'cancel_url'           => '',
			'reschedule_url'       => '',
			'cancellation_contact' => $this->contact_sentence( 'cancel' ),
			'rescheduling_contact' => $this->contact_sentence( 'reschedule' ),
		);

		/**
		 * Filters email template variables. Future add-ons may add values.
		 *
		 * @param array<string,string> $variables Template variables.
		 * @param array<string,mixed>  $booking   Joined booking row.
		 */
		if ( MultilingualText::forced() ) {
			$variables['service_name']  = MultilingualText::translate( $variables['service_name'], 'service-' . (int) ( $booking['service_id'] ?? 0 ) . '-name' );
			$variables['location_name'] = MultilingualText::translate( $variables['location_name'], 'location-' . (int) ( $booking['location_id'] ?? 0 ) . '-name' );
		}
		return apply_filters( 'abientot_email_template_variables', $variables, $booking );
	}

	/**
	 * @return array<string,string>
	 */
	private function sample_variables(): array {
		$settings = Settings::values();

		return array(
			'business_name'        => (string) $settings['business_name'],
			'booking_id'           => '123',
			'customer_name'        => __( 'Sample Customer', 'abientot' ),
			'customer_email'       => 'customer@example.com',
			'customer_phone'       => '+1 555 0100',
			'service_name'         => __( 'Sample Service', 'abientot' ),
			'staff_name'           => __( 'Default Staff', 'abientot' ),
			'location_name'        => __( 'Main Location', 'abientot' ),
			'status'               => __( 'Pending', 'abientot' ),
			'start'                => \Abientot\Support\Locale::date( DateTimeHelper::datetime_display_format(), time() + DAY_IN_SECONDS, DateTimeHelper::business_timezone() ),
			'end'                  => \Abientot\Support\Locale::date( DateTimeHelper::datetime_display_format(), time() + DAY_IN_SECONDS + HOUR_IN_SECONDS, DateTimeHelper::business_timezone() ),
			'price'                => 'USD 75.00',
			'currency'             => 'USD',
			'payment_status'       => __( 'Unpaid', 'abientot' ),
			'customer_note'        => __( 'Sample customer note.', 'abientot' ),
			'site_name'            => (string) get_bloginfo( 'name' ),
			'site_url'             => home_url( '/' ),
			'cancel_url'           => '',
			'reschedule_url'       => '',
			'cancellation_contact' => $this->contact_sentence( 'cancel' ),
			'rescheduling_contact' => $this->contact_sentence( 'reschedule' ),
		);
	}

	private function contact_sentence( string $action ): string {
		$contact = $this->contact_details();
		if ( 'cancel' === $action ) {
			return sprintf(
				/* translators: 1: phone number, 2: email address. */
				__( 'To cancel this booking, please contact us by phone at %1$s or by email at %2$s.', 'abientot' ),
				$contact['phone'],
				$contact['email']
			);
		}

		return sprintf(
			/* translators: 1: phone number, 2: email address. */
			__( 'To reschedule this booking, please contact us by phone at %1$s or by email at %2$s.', 'abientot' ),
			$contact['phone'],
			$contact['email']
		);
	}

	/**
	 * @return array{phone:string,email:string}
	 */
	private function contact_details(): array {
		$settings = Settings::values();
		$location = $this->locations->default_location();
		$email    = is_array( $location ) && is_email( (string) ( $location['email'] ?? '' ) ) ? (string) $location['email'] : (string) $settings['email_reply_to_address'];
		$phone    = is_array( $location ) && '' !== trim( (string) ( $location['phone'] ?? '' ) ) ? (string) $location['phone'] : __( 'the business phone number', 'abientot' );

		if ( ! is_email( $email ) ) {
			$email = (string) get_option( 'admin_email' );
		}

		return array(
			'phone' => $phone,
			'email' => $email,
		);
	}

	/**
	 * @param array<string,string> $variables Template variables.
	 */
	private function render_template( string $template, array $variables ): string {
		$replace = array();
		foreach ( $variables as $key => $value ) {
			$replace[ '{' . $key . '}' ] = $value;
		}

		return strtr( $template, $replace );
	}

	private function setting( string $key ): string {
		$settings = Settings::values();
		return isset( $settings[ $key ] ) ? (string) $settings[ $key ] : '';
	}

	private function format_booking_time( string $utc_datetime, string $timezone ): string {
		try {
			return DateTimeHelper::format_utc_datetime( $utc_datetime, $timezone );
		} catch ( Exception $exception ) {
			return get_date_from_gmt( $utc_datetime, 'Y-m-d H:i' );
		}
	}

	private function plain_text( string $value ): string {
		$value = wp_strip_all_tags( $value );
		$value = str_replace( array( "\r\n", "\r" ), "\n", $value );

		return trim( $value );
	}

	private function html_body( string $value ): string {
		$value = str_replace( array( "\r\n", "\r" ), "\n", $value );
		if ( $value === wp_strip_all_tags( $value ) ) {
			$value = wpautop( $value );
		}

		return wp_kses_post( $value );
	}

	/**
	 * Adds the "Powered by Abientot" line only when the administrator turned it on in the
	 * email settings. Templates saved by 1.0.x contain the line in their HTML: it is removed
	 * first, so it never appears without that choice.
	 */
	private function with_credit( string $body ): string {
		$body = self::without_saved_credit( $body );
		if ( empty( Settings::values()['email_show_credit'] ) ) {
			return $body;
		}
		$credit  = '<div style="padding:15px 30px;border-top:1px solid #eef0f2;color:#9ca3af;font-size:11px;text-align:center;">' . esc_html__( 'Powered by Abientot', 'abientot' ) . '</div>';
		$trimmed = rtrim( $body );
		// Inside the card of the default design; after the content for custom HTML.
		return str_ends_with( $trimmed, '</div></div></div>' ) ? substr( $trimmed, 0, -12 ) . $credit . '</div></div>' : $body . $credit;
	}

	/** Removes the "Powered by Abientot" line that templates saved by 1.0.x contain. */
	private static function without_saved_credit( string $body ): string {
		return (string) preg_replace( '#<div style="[^"]*\#eef0f2[^"]*11px[^"]*">[^<]*</div>#i', '', $body );
	}

	private function clean_header_value( string $value ): string {
		return trim( str_replace( array( "\r", "\n" ), '', wp_strip_all_tags( $value ) ) );
	}
}