<?php
namespace ArrayFunnel\Features\OrderBumps\Services;

defined( 'ABSPATH' ) || exit;

/**
 * Order bump storage and checkout integration.
 *
 * Bumps live in a dedicated table because they are queried by status and priority on every
 * checkout render, which the options and post-meta APIs do not index for.
 */
final class OrderBump {

    /**
     * Display templates shipped in views/.
     */
    private const TEMPLATES = [ 'classic', 'highlight', 'minimal' ];
    /**
     * Order IDs whose bump conversion has already been tracked.
     *
     * @var array<int, bool>
     */
    private array $tracked_conversion_orders = [];

    public function __construct( bool $registerHooks = true ) {
        if ( ! $registerHooks ) {
            return;
        }

        // Keep cleanup registered while disabled, including for returning shoppers
        // whose saved cart still contains a previously selected bump.
        add_action( 'woocommerce_cart_loaded_from_session', [ $this, 'syncDisabledBumps' ], 1 );
        add_action( 'woocommerce_before_calculate_totals', [ $this, 'removeDisabledBumps' ], 1 );

        // Render bump on checkout
        add_action( 'woocommerce_review_order_before_submit', [ $this, 'renderBump' ], 10 );

        // Handle bump add via AJAX
        add_action( 'wp_ajax_arrayfunnel_add_bump', [ $this, 'ajaxAddBump' ] );
        add_action( 'wp_ajax_nopriv_arrayfunnel_add_bump', [ $this, 'ajaxAddBump' ] );

        // Remove bump if unchecked
        add_action( 'wp_ajax_arrayfunnel_remove_bump', [ $this, 'ajaxRemoveBump' ] );
        add_action( 'wp_ajax_nopriv_arrayfunnel_remove_bump', [ $this, 'ajaxRemoveBump' ] );

        // Track bump acceptance on order create
        add_action( 'woocommerce_checkout_create_order_line_item', [ $this, 'markBumpItem' ], 10, 4 );

        // Track conversion event (classic + blocks + payment callbacks).
        add_action( 'woocommerce_checkout_order_created', [ $this, 'trackBumpConversion' ], 10, 1 );
        add_action( 'woocommerce_checkout_order_processed', [ $this, 'trackBumpConversionByOrderId' ], 10, 3 );
        add_action( 'woocommerce_store_api_checkout_order_processed', [ $this, 'trackBumpConversion' ], 10, 1 );
        add_action( 'woocommerce_payment_complete', [ $this, 'trackBumpConversionByOrderId' ], 10, 1 );
    }

    public static function isEnabled(): bool {
        return 'yes' === get_option( 'arrayfunnel_order_bumps_enabled', 'yes' );
    }

    /** Recalculate cached totals after removing bumps from a returning cart. */
    public function syncDisabledBumps( $cart ): void {
        if ( $this->removeDisabledBumps( $cart ) ) {
            $cart->calculate_totals();
        }
    }

    /**
     * Remove only module-added cart lines, leaving ordinary purchases untouched.
     * Clear their undo entries as well so a disabled offer cannot be restored.
     */
    public function removeDisabledBumps( $cart ): bool {
        if ( self::isEnabled() || ! $cart instanceof \WC_Cart ) {
            return false;
        }

        $changed = false;
        foreach ( $cart->get_cart() as $key => $item ) {
            if ( isset( $item['arrayfunnel_bump_id'] ) ) {
                $changed = $cart->remove_cart_item( $key ) || $changed;
            }
        }

        $removed_items = $cart->get_removed_cart_contents();
        foreach ( $removed_items as $key => $item ) {
            if ( isset( $item['arrayfunnel_bump_id'] ) ) {
                unset( $removed_items[ $key ] );
                $changed = true;
            }
        }
        $cart->set_removed_cart_contents( $removed_items );

        return $changed;
    }

    public function renderBump(): void {
        if ( ! self::isEnabled() || ! function_exists( 'WC' ) || ! WC()->cart ) {
            return;
        }

        $bumps = $this->getActiveBumpsForCart();
        if ( empty( $bumps ) ) {
            return;
        }

        $max_display = max( 1, (int) apply_filters( 'arrayfunnel_order_bump_max_display', 10 ) );
        $shown       = 0;

        foreach ( $bumps as $bump ) {
            if ( $shown >= $max_display ) {
                break;
            }

            $product = wc_get_product( $bump->product_id );
            if ( ! $product || ! $product->is_purchasable() || ! $product->is_in_stock() ) {
                continue;
            }

            $template = (string) ( $bump->template ?? 'classic' );
            if ( ! in_array( $template, self::TEMPLATES, true ) ) {
                $template = 'classic';
            }

            $this->trackEvent( 'bump_impression', (int) $bump->id );

            include dirname( __DIR__ ) . "/views/bump-{$template}.php";
            ++$shown;
        }
    }

    public function ajaxAddBump(): void {
        check_ajax_referer( 'arrayfunnel_checkout_nonce', 'arrayfunnel_nonce' );
        $this->requireEnabled();
        $this->requireCart();

        $bump_id    = absint( wp_unslash( $_POST['arrayfunnel_bump_id'] ?? 0 ) );
        $product_id = absint( wp_unslash( $_POST['arrayfunnel_product_id'] ?? 0 ) );

        if ( ! $bump_id || ! $product_id ) {
            wp_send_json_error( __( 'Invalid request.', 'arrayfunnel' ), 400 );
        }

        // Verify product
        $product = wc_get_product( $product_id );
        if ( ! $product || ! $product->is_purchasable() ) {
            wp_send_json_error( __( 'Product not available.', 'arrayfunnel' ), 400 );
        }

        // Add to cart with bump flag
        try {
            $cart_item_key = WC()->cart->add_to_cart( $product_id, 1, 0, [], [
                'arrayfunnel_bump_id' => $bump_id,
            ] );

            if ( ! $cart_item_key ) {
                // Check if there are any notices from WooCommerce
                $notices = wc_get_notices( 'error' );
                $message = ! empty( $notices ) ? wp_strip_all_tags( (string) ( $notices[0]['notice'] ?? '' ) ) : __( 'Could not add product to cart. It might require selection of options.', 'arrayfunnel' );
                wc_clear_notices();
                wp_send_json_error( $message, 400 );
            }
        } catch ( \Exception $e ) {
            wp_send_json_error( __( 'Could not add product to cart.', 'arrayfunnel' ), 500 );
        }

        $this->trackEvent( 'bump_accepted', $bump_id );

        // Important: Force calculation and session save
        WC()->cart->calculate_totals();
        WC()->cart->maybe_set_cart_cookies();

        if ( is_object( WC()->session ) ) {
            WC()->session->set( 'cart', WC()->cart->get_cart_for_session() );
        }

        // Return updated totals and fragments for the frontend
        $fragments = [];
        if ( function_exists( 'woocommerce_order_review' ) ) {
            ob_start();
            woocommerce_order_review();
            $fragments['.woocommerce-checkout-review-order-table'] = ob_get_clean();
        }

        wp_send_json_success( [
            'cart_total' => WC()->cart->get_total(),
            'fragments'  => $fragments,
            'message'    => __( 'Added to your order!', 'arrayfunnel' ),
        ] );
    }

    public function ajaxRemoveBump(): void {
        check_ajax_referer( 'arrayfunnel_checkout_nonce', 'arrayfunnel_nonce' );
        $this->requireEnabled();
        $this->requireCart();

        $product_id = absint( wp_unslash( $_POST['arrayfunnel_product_id'] ?? 0 ) );

        foreach ( WC()->cart->get_cart() as $key => $item ) {
            if ( (int) $item['product_id'] === $product_id && isset( $item['arrayfunnel_bump_id'] ) ) {
                WC()->cart->remove_cart_item( $key );
                break;
            }
        }

        WC()->cart->calculate_totals();
        WC()->cart->maybe_set_cart_cookies();

        if ( is_object( WC()->session ) ) {
            WC()->session->set( 'cart', WC()->cart->get_cart_for_session() );
        }

        $fragments = [];
        if ( function_exists( 'woocommerce_order_review' ) ) {
            ob_start();
            woocommerce_order_review();
            $fragments['.woocommerce-checkout-review-order-table'] = ob_get_clean();
        }

        wp_send_json_success( [
            'cart_total' => WC()->cart->get_total(),
            'fragments'  => $fragments
        ] );
    }

    /** Abort the request when WooCommerce has no cart to act on. */
    private function requireCart(): void {
        if ( ! function_exists( 'WC' ) || ! WC()->cart ) {
            wp_send_json_error( __( 'Cart is unavailable.', 'arrayfunnel' ), 400 );
        }
    }

    /** Reject stale checkout controls after the administrator disables the module. */
    private function requireEnabled(): void {
        if ( ! self::isEnabled() ) {
            wp_send_json_error( __( 'Order bumps are disabled.', 'arrayfunnel' ), 403 );
        }
    }

    public function markBumpItem( \WC_Order_Item_Product $item, string $cart_item_key, array $cart_item, \WC_Order $order ): void {
        if ( self::isEnabled() && isset( $cart_item['arrayfunnel_bump_id'] ) ) {
            $item->add_meta_data( '_arrayfunnel_bump_id', (int) $cart_item['arrayfunnel_bump_id'], true );
            $item->add_meta_data( '_arrayfunnel_is_bump', true, true );
        }
    }

    public function trackBumpConversion( $order ): void {
        if ( is_numeric( $order ) ) {
            $this->trackBumpConversionByOrderId( (int) $order );
            return;
        }

        if ( ! $order instanceof \WC_Order ) {
            return;
        }

        $order_id = (int) $order->get_id();
        if ( isset( $this->tracked_conversion_orders[ $order_id ] ) ) {
            return;
        }
        $this->tracked_conversion_orders[ $order_id ] = true;

        foreach ( $order->get_items() as $item ) {
            $bump_id = $item->get_meta( '_arrayfunnel_bump_id' );
            if ( $bump_id ) {
                $this->trackEvent( 'bump_converted', (int) $bump_id, $order_id );
            }
        }
    }

    public function trackBumpConversionByOrderId( int $order_id ): void {
        if ( $order_id <= 0 ) {
            return;
        }

        $order = wc_get_order( $order_id );
        if ( ! $order instanceof \WC_Order ) {
            return;
        }

        $this->trackBumpConversion( $order );
    }

    /**
     * Get every active bump matching the current cart.
     *
     * @return array<int, object>
     */
    public function getActiveBumpsForCart(): array {
        if ( ! self::isEnabled() ) {
            return [];
        }

        global $wpdb;

        // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery,WordPress.DB.DirectDatabaseQuery.NoCaching
        $bumps = $wpdb->get_results(
            $wpdb->prepare(
                "SELECT * FROM {$wpdb->prefix}arrayfunnel_order_bumps WHERE status = %d ORDER BY priority ASC",
                1
            )
        );

        if ( empty( $bumps ) ) {
            return [];
        }

        $matched = [];
        foreach ( $bumps as $bump ) {
            if ( $this->checkCondition( $bump ) && ! $this->isAlreadyInCart( (int) $bump->product_id ) ) {
                $matched[] = $bump;
            }
        }

        return $matched;
    }

    private function checkCondition( object $bump ): bool {
        $type  = $bump->condition_type ?? 'all';
        $value = $bump->condition_value ?? '';

        switch ( $type ) {
            case 'all':
                return true;

            case 'product':
                $product_ids = array_map( 'absint', (array) json_decode( $value, true ) );
                foreach ( WC()->cart->get_cart() as $item ) {
                    if ( in_array( (int) $item['product_id'], $product_ids, true ) ) {
                        return true;
                    }
                }
                return false;

            case 'category':
                $category_ids = array_map( 'absint', (array) json_decode( $value, true ) );
                foreach ( WC()->cart->get_cart() as $item ) {
                    $terms = wp_get_post_terms( $item['product_id'], 'product_cat', [ 'fields' => 'ids' ] );
                    if ( array_intersect( $category_ids, $terms ) ) {
                        return true;
                    }
                }
                return false;

            case 'cart_total':
                $data  = json_decode( $value, true );
                $min   = (float) ( $data['min'] ?? 0 );
                $max   = (float) ( $data['max'] ?? PHP_INT_MAX );
                $total = (float) WC()->cart->get_cart_contents_total();
                return $total >= $min && $total <= $max;

            default:
                return true;
        }
    }

    private function isAlreadyInCart( int $product_id ): bool {
        foreach ( WC()->cart->get_cart() as $item ) {
            if ( (int) $item['product_id'] === $product_id ) {
                return true;
            }
        }
        return false;
    }

    private function trackEvent( string $event_type, int $bump_id, int $order_id = 0 ): void {
        global $wpdb;
        // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery,WordPress.DB.DirectDatabaseQuery.NoCaching
        $inserted = $wpdb->insert(
            $wpdb->prefix . 'arrayfunnel_analytics',
            [
                'event_type' => $event_type,
                'order_id'   => $order_id > 0 ? $order_id : 0,
                'meta'       => wp_json_encode( [ 'bump_id' => $bump_id ] ),
                'session_id' => $this->getSessionId(),
                'created_at' => current_time( 'mysql', true ),
            ],
            [ '%s', '%d', '%s', '%s', '%s' ]
        );

        if ( false !== $inserted ) {
            $this->invalidateAnalyticsCache();
        }
    }

    private function invalidateAnalyticsCache(): void {
        global $wpdb;

        $patterns = [
            '_transient_arrayfunnel_overview_%',
            '_transient_timeout_arrayfunnel_overview_%',
            '_transient_arrayfunnel_revenue_chart_%',
            '_transient_timeout_arrayfunnel_revenue_chart_%',
            '_transient_arrayfunnel_events_log_%',
            '_transient_timeout_arrayfunnel_events_log_%',
        ];

        foreach ( $patterns as $pattern ) {
            // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery,WordPress.DB.DirectDatabaseQuery.NoCaching
            $wpdb->query(
                $wpdb->prepare(
                    "DELETE FROM {$wpdb->options}
                     WHERE option_name LIKE %s",
                    $pattern
                )
            );
        }
    }

    private function getSessionId(): string {
        if ( function_exists( 'WC' ) && WC()->session ) {
            $customer_id = WC()->session->get_customer_id();
            if ( ! empty( $customer_id ) ) {
                return hash( 'sha256', 'arrayfunnel_analytics|' . (string) $customer_id );
            }
        }

        return wp_generate_uuid4();
    }

    /**
     * Get bumps for the REST API and admin application.
     *
     * @param int $limit  Maximum number of records.
     * @param int $offset Record offset.
     */
    public function getBumps( int $limit = 100, int $offset = 0 ): array {
        global $wpdb;
        // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery,WordPress.DB.DirectDatabaseQuery.NoCaching
        return $wpdb->get_results(
            $wpdb->prepare(
                "SELECT * FROM {$wpdb->prefix}arrayfunnel_order_bumps ORDER BY priority ASC LIMIT %d OFFSET %d",
                $limit,
                $offset
            )
        );
    }

    public function countBumps( ?int $status = null ): int {
        global $wpdb;

        if ( null === $status ) {
            // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery,WordPress.DB.DirectDatabaseQuery.NoCaching
            return (int) $wpdb->get_var( "SELECT COUNT(*) FROM {$wpdb->prefix}arrayfunnel_order_bumps" );
        }

        // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery,WordPress.DB.DirectDatabaseQuery.NoCaching
        return (int) $wpdb->get_var(
            $wpdb->prepare(
                "SELECT COUNT(*) FROM {$wpdb->prefix}arrayfunnel_order_bumps WHERE status = %d",
                $status
            )
        );
    }

    public function getBump( int $id ): ?object {
        global $wpdb;
        // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery,WordPress.DB.DirectDatabaseQuery.NoCaching
        return $wpdb->get_row(
            $wpdb->prepare(
                "SELECT * FROM {$wpdb->prefix}arrayfunnel_order_bumps WHERE id = %d",
                $id
            )
        );
    }

    public function createBump( array $data ): int {
        global $wpdb;
        // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery,WordPress.DB.DirectDatabaseQuery.NoCaching
        $wpdb->insert(
            $wpdb->prefix . 'arrayfunnel_order_bumps',
            [
                'title'            => sanitize_text_field( $data['title'] ?? '' ),
                'product_id'       => absint( $data['product_id'] ?? 0 ),
                'condition_type'   => sanitize_key( $data['condition_type'] ?? 'all' ),
                'condition_value'  => wp_json_encode( $data['condition_value'] ?? null ),
                'display_settings' => wp_json_encode( $data['display_settings'] ?? [] ),
                'template'         => sanitize_key( $data['template'] ?? 'classic' ),
                'status'           => absint( $data['status'] ?? 1 ),
                'priority'         => absint( $data['priority'] ?? 0 ),
                'created_at'       => current_time( 'mysql', true ),
            ],
            [ '%s', '%d', '%s', '%s', '%s', '%s', '%d', '%d', '%s' ]
        );
        return (int) $wpdb->insert_id;
    }

    /**
     * Update the supplied columns of a bump.
     *
     * @param int                  $id   Bump ID.
     * @param array<string, mixed> $data Columns to write. Unknown keys are ignored.
     */
    public function updateBump( int $id, array $data ): bool {
        global $wpdb;

        $columns = [
            'title'            => [ '%s', static fn( $value ) => sanitize_text_field( (string) $value ) ],
            'product_id'       => [ '%d', 'absint' ],
            'condition_type'   => [ '%s', static fn( $value ) => sanitize_key( (string) $value ) ],
            'condition_value'  => [ '%s', 'wp_json_encode' ],
            'display_settings' => [ '%s', 'wp_json_encode' ],
            'template'         => [ '%s', static fn( $value ) => sanitize_key( (string) $value ) ],
            'status'           => [ '%d', 'absint' ],
            'priority'         => [ '%d', 'absint' ],
        ];

        $update = [];
        $format = [];

        foreach ( $columns as $column => [ $placeholder, $sanitizer ] ) {
            if ( ! array_key_exists( $column, $data ) ) {
                continue;
            }

            $update[ $column ] = $sanitizer( $data[ $column ] );
            $format[]          = $placeholder;
        }

        if ( empty( $update ) ) {
            return false;
        }

        // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery,WordPress.DB.DirectDatabaseQuery.NoCaching
        return (bool) $wpdb->update(
            $wpdb->prefix . 'arrayfunnel_order_bumps',
            $update,
            [ 'id' => $id ],
            $format,
            [ '%d' ]
        );
    }

    public function deleteBump( int $id ): bool {
        global $wpdb;
        // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery,WordPress.DB.DirectDatabaseQuery.NoCaching
        return (bool) $wpdb->delete(
            $wpdb->prefix . 'arrayfunnel_order_bumps',
            [ 'id' => $id ],
            [ '%d' ]
        );
    }
}