<?php
/**
 * Cash-on-delivery confirmation over WhatsApp.
 *
 * New COD order → the "Cash-on-delivery confirmation" event's template (with
 * Confirm / Cancel quick-reply buttons) is sent instead of "Order Placed".
 * While the customer hasn't answered, the store's automatic "processing" /
 * "on hold" / "pending" messages for that order are held back so the
 * customer isn't told "order confirmed" before they confirmed it.
 *
 * The customer's tap reaches 6rsh, which posts a signed `cod.answered`
 * callback to this store (same channel + secret as plan.changed):
 *   confirmed → order note + meta, order moved to the status picked in
 *               Notifications → "When the customer confirms" (default
 *               Processing; "Don't change" keeps the old note-only behaviour)
 *   cancelled → order note + meta, order set to Cancelled (stock restored)
 *
 * 6rsh also sends answers for orders whose ordinary status message used a
 * template with Confirm / Cancel buttons, so those orders need not be COD.
 *
 * Free on every plan and not counted against the notification limit.
 *
 * @package SixRsh_WhatsApp
 */

defined( 'ABSPATH' ) || exit;

/**
 * Class SixRsh_COD
 */
class SixRsh_COD {

	const EVENT       = 'cod_confirmation';
	const META_STATUS = '_sixrsh_cod_status'; // pending | confirmed | cancelled

	/** Only orders still in one of these get moved on confirm — never backwards from shipped/completed. */
	const CONFIRM_FROM = array( 'pending', 'on-hold', 'processing' );

	/**
	 * Status (without wc- prefix) a confirmed order moves to; '' = leave it.
	 *
	 * @return string
	 */
	public static function confirmed_status(): string {
		$settings = get_option( 'sixrsh_settings', array() );
		$status   = isset( $settings['cod']['confirmed_status'] ) ? (string) $settings['cod']['confirmed_status'] : 'processing';
		$status   = preg_replace( '/^wc-/', '', $status );
		if ( '' === $status || ! function_exists( 'wc_get_order_statuses' ) ) {
			return '';
		}

		return array_key_exists( 'wc-' . $status, wc_get_order_statuses() ) ? $status : '';
	}

	/**
	 * Hooks.
	 *
	 * @return void
	 */
	public static function init(): void {
		// Self-heal: stores connected before the callback existed never
		// registered one, so answers (and plan changes) could not reach them.
		// admin_init only — never put an outbound HTTP call in front of a
		// shopper's page load.
		add_action( 'admin_init', array( __CLASS__, 'maybe_register_callback' ), 20 );
	}

	/**
	 * Is the COD confirmation event switched on with a template mapped?
	 *
	 * @return bool
	 */
	public static function enabled(): bool {
		if ( ! get_option( 'sixrsh_event_' . self::EVENT . '_enabled', false ) ) {
			return false;
		}
		$raw = get_option( 'sixrsh_event_' . self::EVENT . '_template', '' );
		$map = $raw ? json_decode( $raw, true ) : null;

		return ! empty( $map['template_id'] );
	}

	/**
	 * Was this order placed with Cash on Delivery?
	 *
	 * @param \WC_Order $order Order.
	 *
	 * @return bool
	 */
	public static function is_cod_order( $order ): bool {
		return $order instanceof \WC_Order && 'cod' === $order->get_payment_method();
	}

	/**
	 * On a new checkout order: queue the COD confirmation when it applies.
	 * Returns true when it did (caller then skips "Order Placed").
	 *
	 * @param \WC_Order $order Order.
	 *
	 * @return bool
	 */
	public static function handle_new_order( $order ): bool {
		try {
			if ( ! self::enabled() || ! self::is_cod_order( $order ) ) {
				return false;
			}
			$order->update_meta_data( self::META_STATUS, 'pending' );
			$order->save_meta_data();
			SixRsh_Order_Hooks::dispatch( $order, self::EVENT );

			return true;
		} catch ( \Throwable $e ) {
			error_log( '[6rsh] COD::handle_new_order exception: ' . $e->getMessage() );
			return false;
		}
	}

	/**
	 * Hold back early status messages while the customer hasn't answered.
	 *
	 * @param int    $order_id Order ID.
	 * @param string $status   Status without wc- prefix.
	 *
	 * @return bool True = do not send this status notification.
	 */
	public static function suppress_status( int $order_id, string $status ): bool {
		if ( ! in_array( $status, array( 'pending', 'processing', 'on-hold' ), true ) ) {
			return false;
		}
		$order = wc_get_order( $order_id );
		if ( ! $order || ! self::is_cod_order( $order ) ) {
			return false;
		}

		return 'pending' === $order->get_meta( self::META_STATUS, true );
	}

	/**
	 * The COD message could not be sent: clear the hold so the store's normal
	 * messages still reach the customer.
	 *
	 * @param \WC_Order $order Order.
	 *
	 * @return void
	 */
	public static function release_hold( $order ): void {
		if ( $order instanceof \WC_Order && 'pending' === $order->get_meta( self::META_STATUS, true ) ) {
			$order->delete_meta_data( self::META_STATUS );
			$order->save_meta_data();
		}
	}

	/**
	 * Apply the customer's answer (from the signed cod.answered callback).
	 *
	 * @param array $data Decoded callback body.
	 *
	 * @return array{success:bool,reason?:string}
	 */
	public static function apply_answer( array $data ): array {
		$order_id = absint( $data['order_id'] ?? 0 );
		$answer   = (string) ( $data['status'] ?? '' );
		if ( ! $order_id || ! in_array( $answer, array( 'confirmed', 'cancelled' ), true ) ) {
			return array( 'success' => false, 'reason' => 'bad_payload' );
		}

		$order = wc_get_order( $order_id );
		if ( ! $order ) {
			return array( 'success' => false, 'reason' => 'order_not_found' );
		}

		// Idempotent: the same answer twice changes nothing.
		if ( $order->get_meta( self::META_STATUS, true ) === $answer ) {
			return array( 'success' => true, 'applied' => true );
		}

		$order->update_meta_data( self::META_STATUS, $answer );

		if ( 'confirmed' === $answer ) {
			$note   = __( '[6rsh] The customer CONFIRMED this order on WhatsApp ✅', '6rsh-messaging-notifications' );
			$target = self::confirmed_status();
			if ( $target && $target !== $order->get_status() && in_array( $order->get_status(), self::CONFIRM_FROM, true ) ) {
				$order->update_status( $target, $note ); // also saves
			} else {
				$order->add_order_note( $note );
				$order->save();
			}
			return array( 'success' => true, 'applied' => true, 'order_status' => $order->get_status() );
		}

		$note = __( '[6rsh] The customer CANCELLED this order on WhatsApp.', '6rsh-messaging-notifications' );
		// Only COD orders are cancelled automatically: a paid order needs a refund first.
		if ( self::is_cod_order( $order ) && in_array( $order->get_status(), array( 'pending', 'processing', 'on-hold' ), true ) ) {
			$order->update_status( 'cancelled', $note ); // also saves + restores stock
		} else {
			// Already shipped/completed, or paid online — never undo that automatically.
			$order->add_order_note( $note . ' ' . __( 'Order status left unchanged — please review it.', '6rsh-messaging-notifications' ) );
			$order->save();
		}

		return array( 'success' => true, 'applied' => true );
	}

	/**
	 * Register the store callback once if it never was (throttled to 6h).
	 *
	 * @return void
	 */
	public static function maybe_register_callback(): void {
		if ( get_option( SixRsh_Entitlements::OPTION_CALLBACK_REGISTERED ) || ! get_option( 'sixrsh_api_key' ) ) {
			return;
		}
		if ( get_transient( 'sixrsh_cb_register_try' ) ) {
			return;
		}
		set_transient( 'sixrsh_cb_register_try', 1, 6 * HOUR_IN_SECONDS );
		SixRsh_Entitlements::register_callback();
	}
}