<?php

namespace WooOrderCart;

use WooOrderCart\DatabaseTables\Database_Tables;
use WooOrderCart\Managers\SettingsManager;
use WooOrderCart\Lifecycle\CartDataManifest;

/**
 * Installs and upgrades the plugin-owned runtime state.
 */
class Installer {

    public const SCHEMA_OPTION = 'ipscmi_order_cart_table_schema_version';
    private const SCHEMA_VERSION = '5';

    private function schema_version(): string {
        return self::SCHEMA_VERSION . ( \IPSCMI\Order\Cart\Config\PackageProfile::from_runtime()->includes_pro() ? ':pro' : ':core' );
    }

    public const VERSION_OPTION = 'ipscmi_order_cart_version';
    public const INSTALLED_OPTION = 'ipscmi_order_cart_installed';
    public const LEGACY_INSTALLED_OPTION = 'ips_wooordecart_installed';
    public const REDIRECT_OPTION = 'ipscmi_order_cart_do_activation_redirect';

    /**
     * Run additive install or upgrade tasks.
     *
     * The version is deliberately persisted last. A failed earlier step can
     * therefore be retried on the next request instead of looking complete.
     */
    public function run( bool $is_activation = true ): void {
        $this->migrate_owned_options();
        self::add_settings();
        $this->create_cartgate_tables();
        $this->migrate_local_pickup_posts();

        if ( $is_activation ) {
            $this->add_redirection_flag();
        }

        $this->clear_transients();
        update_option( self::SCHEMA_OPTION, $this->schema_version(), false );
        $this->add_version();
    }

    /**
     * Return whether the stored schema/version needs reconciliation.
     */
    public function needs_upgrade(): bool {
        $stored_version = (string) get_option( self::VERSION_OPTION, '' );

        $missing = new \stdClass();
        $installed = get_option( self::INSTALLED_OPTION, $missing );

        if ( $missing === $installed ) {
            return true;
        }

        return (string) get_option( self::SCHEMA_OPTION, '' ) !== $this->schema_version() || '' === $stored_version || version_compare( $stored_version, $this->current_version(), '!=' );
    }

    /** Copy only known IPS-owned keys. Retry safely after failure and never overwrite a canonical value. */
    private function migrate_owned_options(): void {
        $missing = new \stdClass();
        foreach ( CartDataManifest::legacy_options() as $legacy => $canonical ) {
            if ( $missing !== get_option( $canonical, $missing ) ) {
                continue;
            }
            $value = get_option( $legacy, $missing );
            if ( $missing === $value ) {
                continue;
            }
            if ( ! add_option( $canonical, $value, '', false ) && $missing === get_option( $canonical, $missing ) ) {
                throw new \RuntimeException( 'Could not migrate an IPS Order Cart option.' );
            }
        }
    }

    /** Preserve IDs and metadata; never claim another plugin's generic posts. */
    private function migrate_local_pickup_posts(): void {
        global $wpdb;

        $post_ids = $wpdb->get_col( $wpdb->prepare(
            "SELECT p.ID FROM {$wpdb->posts} p WHERE p.post_type = %s
             AND EXISTS (SELECT 1 FROM {$wpdb->postmeta} m WHERE m.post_id = p.ID AND m.meta_key = %s)",
            'localpickup',
            CartDataManifest::LOCAL_PICKUP_META_KEY
        ) );

        if ( '' !== (string) $wpdb->last_error ) {
            throw new \RuntimeException( 'Could not read IPS Order Cart pickup locations for migration.' );
        }

        foreach ( $post_ids as $post_id ) {
            $updated = $wpdb->update(
                $wpdb->posts,
                [ 'post_type' => CartDataManifest::LOCAL_PICKUP_POST_TYPE ],
                [ 'ID' => (int) $post_id, 'post_type' => 'localpickup' ],
                [ '%s' ],
                [ '%d', '%s' ]
            );
            if ( false === $updated ) {
                throw new \RuntimeException( 'Could not migrate an IPS Order Cart pickup location.' );
            }
            clean_post_cache( (int) $post_id );
        }
    }

    /**
     * Reconcile additive install tasks after a normal WordPress plugin update.
     */
    public function maybe_upgrade(): bool {
        if ( ! $this->needs_upgrade() ) {
            return false;
        }

        $this->run( false );

        return true;
    }

    /**
     * Persist the current plugin version. This must remain the final run step.
     */
    public function add_version(): void {
        $this->migrate_installation_marker();
        update_option( self::VERSION_OPTION, $this->current_version(), false );
    }

    /**
     * Seed SettingsManager values without replacing merchant configuration.
     */
    public static function add_settings(): void {
        SettingsManager::instance()->add_setting( 'enable', 'no' );
        SettingsManager::instance()->add_setting( 'allow_uninstall', 'no' );
    }

    /**
     * Clear version-sensitive asset manifests.
     */
    public function clear_transients(): void {
        global $wpdb;

        foreach ( [ 'frontend', 'backend' ] as $type ) {
            delete_transient( 'ipscmi_order_cart_manifest_' . $type );
        }

        $manifest_prefix = 'ipscmi_order_cart_manifest_';
        $transient_names = [];

        foreach ( [ '_transient_', '_transient_timeout_' ] as $storage_prefix ) {
            $option_names = $wpdb->get_col(
                $wpdb->prepare(
                    "SELECT option_name FROM {$wpdb->options} WHERE option_name LIKE %s",
                    $wpdb->esc_like( $storage_prefix . $manifest_prefix ) . '%'
                )
            );

            foreach ( (array) $option_names as $option_name ) {
                $transient_names[] = substr( (string) $option_name, strlen( $storage_prefix ) );
            }
        }

        foreach ( array_unique( $transient_names ) as $transient_name ) {
            delete_transient( $transient_name );
        }
    }

    /**
     * Flag a genuine activation, but not a background version upgrade.
     */
    public function add_redirection_flag(): void {
        add_option( self::REDIRECT_OPTION, true, '', false );
    }

    /**
     * Install every table registered as owned by this plugin.
     */
    public function create_cartgate_tables(): void {
        Database_Tables::install_tables();
    }

    /**
     * Backward-compatible entry point used by older integrations.
     */
    public static function drop_cartgate_tables(): void {
        Database_Tables::drop_tables();
    }

    /**
     * Move the historic misspelled marker to the canonical option.
     *
     * The legacy value remains available until an explicit full uninstall.
     */
    private function migrate_installation_marker(): void {
        $missing = new \stdClass();
        $installed = get_option( self::INSTALLED_OPTION, $missing );

        if ( $missing !== $installed ) {
            return;
        }

        $legacy_installed = get_option( self::LEGACY_INSTALLED_OPTION, $missing );
        $installed_at = $missing !== $legacy_installed ? $legacy_installed : time();

        update_option( self::INSTALLED_OPTION, $installed_at, false );
    }

    /**
     * Resolve the authoritative plugin version for activation and upgrades.
     */
    private function current_version(): string {
        if ( defined( 'IPSCMI_ORDER_CART_VERSION' ) ) {
            return (string) IPSCMI_ORDER_CART_VERSION;
        }

        if ( defined( 'IPSCMI_ORDER_CART_VERSION' ) ) {
            return (string) IPSCMI_ORDER_CART_VERSION;
        }

        $plugin_file = defined( 'IPSCMI_ORDER_CART_RUNTIME_FILE' )
            ? IPSCMI_ORDER_CART_RUNTIME_FILE
            : dirname( __DIR__, 2 ) . '/ips-order-cart.php';
        $headers = function_exists( 'get_file_data' )
            ? get_file_data( $plugin_file, [ 'Version' => 'Version' ] )
            : [];

        return ! empty( $headers['Version'] ) ? (string) $headers['Version'] : '0.0.0';
    }
}