<?php
namespace ArrayFunnel\Features\MainAdmin\REST;

defined( 'ABSPATH' ) || exit;

/**
 * Reads and writes the plugin settings, and backs the product picker used by order bumps.
 */
final class SettingsController extends \ArrayFunnel\Supports\BaseRestController {

    private array $allowedKeys = [
        'arrayfunnel_order_bumps_enabled',
        'arrayfunnel_side_cart_enabled',
        'arrayfunnel_side_cart_free_shipping',
        'arrayfunnel_side_cart_theme',
        'arrayfunnel_side_cart_radius',
        'arrayfunnel_side_cart_accent',
        'arrayfunnel_side_cart_open_mode',
        'arrayfunnel_checkout_optimized',
        'arrayfunnel_checkout_countdown',
        'arrayfunnel_checkout_countdown_mins',
        'arrayfunnel_checkout_trust_badges',
        'arrayfunnel_abandon_threshold',
        'arrayfunnel_abandon_email_1_delay',
        'arrayfunnel_abandon_email_2_delay',
        'arrayfunnel_abandon_email_3_delay',
        'arrayfunnel_abandon_coupon_2',
        'arrayfunnel_abandon_coupon_3',
        'arrayfunnel_abandon_email_from_name',
        'arrayfunnel_abandon_email_from_email',
        'arrayfunnel_field_settings',
        'arrayfunnel_analytics_retention_days',
    ];

    public function registerRoutes(): void {
        register_rest_route( $this->namespace, '/settings', [
            [
                'methods'             => \WP_REST_Server::READABLE,
                'callback'            => [ $this, 'getSettings' ],
                'permission_callback' => [ $this, 'checkPermission' ],
            ],
            [
                'methods'             => \WP_REST_Server::CREATABLE,
                'callback'            => [ $this, 'saveSettings' ],
                'permission_callback' => [ $this, 'checkPermission' ],
                'args'                => [
                    'settings' => [
                        'required'          => false,
                        'validate_callback' => function ( $value ) {
                            return is_array( $value ) || is_object( $value ) || null === $value;
                        },
                    ],
                ],
            ],
        ] );

        register_rest_route( $this->namespace, '/settings/meta', [
            [
                'methods'             => \WP_REST_Server::READABLE,
                'callback'            => [ $this, 'getSettingsMeta' ],
                'permission_callback' => [ $this, 'checkPermission' ],
            ],
        ] );

        // Product search for order-bump selectors.
        register_rest_route( $this->namespace, '/products/search', [
            [
                'methods'             => \WP_REST_Server::READABLE,
                'callback'            => [ $this, 'searchProducts' ],
                'permission_callback' => [ $this, 'checkPermission' ],
                'args'                => [
                    'q' => [
                        'required'          => true,
                        'sanitize_callback' => 'sanitize_text_field',
                        'validate_callback' => function ( $value ) {
                            return '' !== trim( (string) $value );
                        },
                    ],
                ],
            ],
        ] );
    }

    public function getSettings(): \WP_REST_Response {
        $settings = [];
        foreach ( $this->allowedKeys as $key ) {
            // Existing stores displayed order bumps before the module switch existed.
            $settings[ $key ] = 'arrayfunnel_order_bumps_enabled' === $key
                ? get_option( $key, 'yes' )
                : get_option( $key );
        }
        return $this->success( $settings );
    }

    public function getSettingsMeta(): \WP_REST_Response {
        return $this->success( $this->settingsMeta() );
    }

    public function saveSettings( \WP_REST_Request $request ): \WP_REST_Response {
        $params  = $request->get_json_params() ?? $request->get_params();
        if ( ! is_array( $params ) ) {
            return $this->error( __( 'Invalid settings payload.', 'arrayfunnel' ), 400, 'arrayfunnel_invalid_payload' );
        }

        $saved   = [];

        foreach ( $this->allowedKeys as $key ) {
            if ( ! array_key_exists( $key, $params ) ) {
                continue;
            }
            $value = $this->sanitizeSetting( $key, $params[ $key ] );
            if ( false === update_option( $key, $value ) ) {
                // WordPress returns false for unchanged values as well as write
                // failures. A failed write must not advance the saved timestamp.
                $missing = new \stdClass();
                $stored = get_option( $key, $missing );
                $matches = is_array( $value )
                    ? $stored === $value
                    : is_scalar( $stored ) && (string) $stored === (string) $value;
                if ( $stored === $missing || ! $matches ) {
                    return $this->error( __( 'Could not save settings. Please try again.', 'arrayfunnel' ), 500, 'arrayfunnel_settings_save_failed' );
                }
            }
            $saved[ $key ] = $value;
        }

        if ( ! empty( $saved ) ) {
            // UTC Unix time is stored separately from editable settings. WordPress
            // applies the site's timezone and display formats when it is read.
            update_option( 'arrayfunnel_settings_last_saved_at', time(), false );
        }

        $this->clearAnalyticsCache();

        return $this->success( [ 'saved' => $saved, 'meta' => $this->settingsMeta() ] );
    }

    /** Saved-time metadata is read-only and never inferred from activation dates. */
    private function settingsMeta(): array {
        $timestamp = max( 0, (int) get_option( 'arrayfunnel_settings_last_saved_at', 0 ) );
        $format = (string) get_option( 'date_format', 'F j, Y' )
            . ' ' . (string) get_option( 'time_format', 'g:i a' );

        return [
            'last_saved_at'           => $timestamp,
            'last_saved_at_formatted' => $timestamp ? wp_date( $format, $timestamp ) : '',
        ];
    }

    public function searchProducts( \WP_REST_Request $request ): \WP_REST_Response {
        $query   = (string) $request->get_param( 'q' );
        $needle  = strtolower( trim( $query ) );
        $results = wc_get_products( [
            'status'   => 'publish',
            'limit'    => 20,
            'orderby'  => 'relevance',
            'search'   => $query,
            'return'   => 'objects',
        ] );

        $products = array_map( function ( \WC_Product $p ) {
            $price_value = (float) $p->get_price();
            $image_id    = absint( $p->get_image_id() );
            return [
                'id'    => $p->get_id(),
                'name'  => $p->get_name(),
                'price_value' => $price_value,
                'price_formatted' => wc_price( $price_value ),
                'image' => wp_get_attachment_image_url( $image_id, 'thumbnail' ) ?: wc_placeholder_img_src(),
                'sku'   => $p->get_sku(),
                'stock' => $p->get_stock_status(),
            ];
        }, $results );

        if ( $needle !== '' && count( $products ) > 1 ) {
            $starts_with = static function ( string $haystack, string $prefix ): bool {
                return $prefix !== '' && 0 === strpos( $haystack, $prefix );
            };
            $contains = static function ( string $haystack, string $fragment ): bool {
                return $fragment !== '' && false !== strpos( $haystack, $fragment );
            };
            $score_for = static function ( array $product ) use ( $needle, $starts_with, $contains ): int {
                $name = strtolower( (string) ( $product['name'] ?? '' ) );
                $sku  = strtolower( (string) ( $product['sku'] ?? '' ) );

                if ( $name === $needle || $sku === $needle ) {
                    return 0;
                }
                if ( $starts_with( $name, $needle ) ) {
                    return 1;
                }
                if ( $contains( $name, $needle ) ) {
                    return 2;
                }
                if ( $starts_with( $sku, $needle ) ) {
                    return 3;
                }
                if ( $contains( $sku, $needle ) ) {
                    return 4;
                }
                return 9;
            };

            foreach ( $products as $i => $product ) {
                $products[ $i ]['_score'] = $score_for( $product );
            }

            usort( $products, static function ( array $a, array $b ) {
                $scoreA = (int) ( $a['_score'] ?? 9 );
                $scoreB = (int) ( $b['_score'] ?? 9 );
                if ( $scoreA !== $scoreB ) {
                    return $scoreA <=> $scoreB;
                }
                return strcasecmp( (string) ( $a['name'] ?? '' ), (string) ( $b['name'] ?? '' ) );
            } );

            foreach ( $products as $i => $product ) {
                unset( $products[ $i ]['_score'] );
            }
        }

        return $this->success( $products );
    }

    /**
     * Sanitize a single setting according to the value it is allowed to hold.
     *
     * @param string $key   Option key, already checked against the allow list.
     * @param mixed  $value Raw value from the request.
     *
     * @return mixed
     */
    private function sanitizeSetting( string $key, $value ) {
        $yes_no_keys = [
            'arrayfunnel_order_bumps_enabled',
            'arrayfunnel_side_cart_enabled',
            'arrayfunnel_checkout_optimized',
            'arrayfunnel_checkout_countdown',
            'arrayfunnel_checkout_trust_badges',
        ];

        $int_keys = [
            'arrayfunnel_analytics_retention_days',
            'arrayfunnel_checkout_countdown_mins',
            'arrayfunnel_abandon_threshold',
            'arrayfunnel_abandon_email_1_delay',
            'arrayfunnel_abandon_email_2_delay',
            'arrayfunnel_abandon_email_3_delay',
        ];

        if ( in_array( $key, $yes_no_keys, true ) ) {
            return $value === 'yes' || $value === true || $value === 1 ? 'yes' : 'no';
        }

        if ( $key === 'arrayfunnel_side_cart_theme' ) {
            $allowed = [ 'light', 'graphite' ];
            $theme   = sanitize_key( (string) $value );
            return in_array( $theme, $allowed, true ) ? $theme : 'light';
        }

        if ( $key === 'arrayfunnel_side_cart_radius' ) {
            $allowed = [ 'soft', 'balanced', 'expressive' ];
            $radius  = sanitize_key( (string) $value );
            return in_array( $radius, $allowed, true ) ? $radius : 'balanced';
        }

        if ( $key === 'arrayfunnel_side_cart_accent' ) {
            $allowed = [ 'emerald', 'black', 'sky' ];
            $accent  = sanitize_key( (string) $value );
            return in_array( $accent, $allowed, true ) ? $accent : 'emerald';
        }

        if ( $key === 'arrayfunnel_side_cart_open_mode' ) {
            $allowed = [ 'always', 'smart' ];
            $mode    = sanitize_key( (string) $value );
            return in_array( $mode, $allowed, true ) ? $mode : 'always';
        }

        if ( in_array( $key, $int_keys, true ) ) {
            return absint( $value );
        }

        if ( $key === 'arrayfunnel_field_settings' ) {
            return is_array( $value ) ? $this->sanitizeFieldSettings( $value ) : [];
        }

        if ( $key === 'arrayfunnel_abandon_email_from_email' ) {
            return sanitize_email( (string) $value );
        }

        if ( $key === 'arrayfunnel_side_cart_free_shipping' ) {
            return '' === trim( (string) $value ) ? '' : (string) max( 0, (float) $value );
        }

        return sanitize_text_field( (string) $value );
    }

    /**
     * Sanitize the checkout field overrides.
     *
     * The shape is fixed: a group name, then a field key, then a scalar override.
     *
     * @param array<string, mixed> $settings Raw field settings.
     *
     * @return array<string, array<string, bool|int|string>>
     */
    private function sanitizeFieldSettings( array $settings ): array {
        $clean = [];

        foreach ( [ 'hidden', 'required', 'labels', 'priority' ] as $group ) {
            if ( ! isset( $settings[ $group ] ) || ! is_array( $settings[ $group ] ) ) {
                continue;
            }

            foreach ( $settings[ $group ] as $field_key => $field_value ) {
                if ( ! is_scalar( $field_value ) && null !== $field_value ) {
                    continue;
                }

                $field_key = sanitize_key( (string) $field_key );
                if ( '' === $field_key ) {
                    continue;
                }

                if ( 'labels' === $group ) {
                    $clean[ $group ][ $field_key ] = sanitize_text_field( (string) $field_value );
                } elseif ( 'priority' === $group ) {
                    $clean[ $group ][ $field_key ] = absint( $field_value );
                } else {
                    $clean[ $group ][ $field_key ] = (bool) $field_value;
                }
            }
        }

        return $clean;
    }

    private function clearAnalyticsCache(): void {
        $windows = [ 7, 30, 90, 365 ];
        foreach ( $windows as $days ) {
            delete_transient( "arrayfunnel_overview_{$days}" );
            delete_transient( "arrayfunnel_revenue_chart_{$days}" );
            delete_transient( "arrayfunnel_events_log_{$days}_50_0" );
        }
    }
}