<?php
namespace WooNooW\Frontend;

/**
 * Template Override
 * Overrides WooCommerce templates to use WooNooW SPA
 */
class TemplateOverride
{

    /**
     * Initialize
     */
    public static function init()
    {
        // Register rewrite rules for BrowserRouter SEO (must be on 'init')
        add_action('init', [__CLASS__, 'register_spa_rewrite_rules']);
        
        // Flush rewrite rules when relevant settings change
        add_action('update_option_woonoow_appearance_settings', function($old_value, $new_value) {
            $old_general = $old_value['general'] ?? [];
            $new_general = $new_value['general'] ?? [];
            
            // Only flush if spa_mode, spa_page, or use_browser_router changed
            $needs_flush = 
                ($old_general['spa_mode'] ?? '') !== ($new_general['spa_mode'] ?? '') ||
                ($old_general['spa_page'] ?? '') !== ($new_general['spa_page'] ?? '') ||
                ($old_general['use_browser_router'] ?? true) !== ($new_general['use_browser_router'] ?? true);
            
            if ($needs_flush) {
                flush_rewrite_rules();
            }
        }, 10, 2);
        
        // Redirect WooCommerce pages to SPA routes early (before template loads)
        add_action('template_redirect', [__CLASS__, 'redirect_wc_pages_to_spa'], 5);
        
        // Serve SPA directly for frontpage routes (priority 1 = very early, before WC)
        add_action('template_redirect', [__CLASS__, 'serve_spa_for_frontpage_routes'], 1);
        
        // Hook to wp_loaded with priority 10 (BEFORE WooCommerce's priority 20)
        // This ensures we process add-to-cart before WooCommerce does
        add_action('wp_loaded', [__CLASS__, 'intercept_add_to_cart'], 10);

        // Use blank template for full-page SPA
        add_filter('template_include', [__CLASS__, 'use_spa_template'], 999);

        // Disable canonical redirects for SPA routes
        add_filter('redirect_canonical', [__CLASS__, 'disable_canonical_redirect'], 10, 2);

        // Override WooCommerce shop page
        add_filter('woocommerce_show_page_title', '__return_false');

        // Replace WooCommerce content with our SPA
        add_action('woocommerce_before_main_content', [__CLASS__, 'start_spa_wrapper'], 5);
        add_action('woocommerce_after_main_content', [__CLASS__, 'end_spa_wrapper'], 999);

        // Remove WooCommerce default content
        remove_action('woocommerce_before_shop_loop', 'woocommerce_result_count', 20);
        remove_action('woocommerce_before_shop_loop', 'woocommerce_catalog_ordering', 30);
        remove_action('woocommerce_before_main_content', 'woocommerce_output_content_wrapper', 10);
        remove_action('woocommerce_after_main_content', 'woocommerce_output_content_wrapper_end', 10);

        // Override single product template
        add_filter('woocommerce_locate_template', [__CLASS__, 'override_template'], 10, 3);

        // Remove theme header and footer when SPA is active
        add_action('get_header', [__CLASS__, 'remove_theme_header']);
        add_action('get_footer', [__CLASS__, 'remove_theme_footer']);
    }
    
    /**
     * Register rewrite rules for BrowserRouter SEO
     * Catches all SPA routes and serves the SPA page
     */
    public static function register_spa_rewrite_rules()
    {
        $appearance_settings = get_option('woonoow_appearance_settings', []);
        $spa_page_id = $appearance_settings['general']['spa_page'] ?? 0;
        
        // Check if BrowserRouter is enabled (default: true for new installs)
        $use_browser_router = $appearance_settings['general']['use_browser_router'] ?? true;
        
        if (!$spa_page_id || !$use_browser_router) {
            return;
        }
        
        $spa_page = get_post($spa_page_id);
        if (!$spa_page) {
            return;
        }
        
        $spa_slug = $spa_page->post_name;
        
        // Check if SPA page is set as WordPress frontpage
        $frontpage_id = (int) get_option('page_on_front');
        $is_spa_frontpage = $frontpage_id && $frontpage_id === (int) $spa_page_id;
        
        if ($is_spa_frontpage) {
            // When SPA is frontpage, add root-level routes
            // /shop, /shop/* → SPA page
            add_rewrite_rule(
                '^shop/?$',
                'index.php?page_id=' . $spa_page_id . '&woonoow_spa_path=shop',
                'top'
            );
            add_rewrite_rule(
                '^shop/(.*)$',
                'index.php?page_id=' . $spa_page_id . '&woonoow_spa_path=shop/$matches[1]',
                'top'
            );
            
            // /product/* → SPA page
            add_rewrite_rule(
                '^product/(.*)$',
                'index.php?page_id=' . $spa_page_id . '&woonoow_spa_path=product/$matches[1]',
                'top'
            );
            
            // /cart → SPA page
            add_rewrite_rule(
                '^cart/?$',
                'index.php?page_id=' . $spa_page_id . '&woonoow_spa_path=cart',
                'top'
            );
            
            // /checkout → SPA page
            add_rewrite_rule(
                '^checkout/?$',
                'index.php?page_id=' . $spa_page_id . '&woonoow_spa_path=checkout',
                'top'
            );
            
            // /my-account, /my-account/* → SPA page
            add_rewrite_rule(
                '^my-account/?$',
                'index.php?page_id=' . $spa_page_id . '&woonoow_spa_path=my-account',
                'top'
            );
            add_rewrite_rule(
                '^my-account/(.*)$',
                'index.php?page_id=' . $spa_page_id . '&woonoow_spa_path=my-account/$matches[1]',
                'top'
            );
            
            // /login, /register, /reset-password → SPA page
            add_rewrite_rule(
                '^login/?$',
                'index.php?page_id=' . $spa_page_id . '&woonoow_spa_path=login',
                'top'
            );
            add_rewrite_rule(
                '^register/?$',
                'index.php?page_id=' . $spa_page_id . '&woonoow_spa_path=register',
                'top'
            );
            add_rewrite_rule(
                '^reset-password/?$',
                'index.php?page_id=' . $spa_page_id . '&woonoow_spa_path=reset-password',
                'top'
            );
        } else {
            // Rewrite /slug/anything to serve the SPA page
            // React Router handles the path after that
            add_rewrite_rule(
                '^' . preg_quote($spa_slug, '/') . '/(.*)$',
                'index.php?page_id=' . $spa_page_id . '&woonoow_spa_path=$matches[1]',
                'top'
            );
        }
        
        // Register query var for the SPA path
        add_filter('query_vars', function($vars) {
            $vars[] = 'woonoow_spa_path';
            return $vars;
        });
    }

    /**
     * Intercept add-to-cart redirect (NOT the add-to-cart itself)
     * Let WooCommerce handle the cart operation properly, we just redirect afterward
     * 
     * This is the proper approach - WooCommerce manages sessions correctly,
     * we just customize where the redirect goes.
     */
    public static function intercept_add_to_cart()
    {
        // Only act if add-to-cart is present
        if (!isset($_GET['add-to-cart'])) {
            return;
        }

        // Get SPA page from appearance settings
        $appearance_settings = get_option('woonoow_appearance_settings', []);
        $spa_page_id = isset($appearance_settings['general']['spa_page']) ? $appearance_settings['general']['spa_page'] : 0;

        if (!$spa_page_id) {
            return; // No SPA page configured, let WooCommerce handle everything
        }

        // Hook into WooCommerce's redirect filter AFTER it adds to cart
        // This is the proper way to customize the redirect destination
        add_filter('woocommerce_add_to_cart_redirect', function ($url) use ($spa_page_id) {
            // Get redirect parameter from original request
            $redirect_to = isset($_GET['redirect']) ? sanitize_text_field($_GET['redirect']) : 'cart';

            // Build redirect URL with hash route for SPA
            $redirect_url = get_permalink($spa_page_id);

            // Determine hash route based on redirect parameter
            $hash_route = '/cart'; // Default
            if ($redirect_to === 'checkout') {
                $hash_route = '/checkout';
            } elseif ($redirect_to === 'shop') {
                $hash_route = '/shop';
            }

            // Return the SPA URL with hash route
            return trailingslashit($redirect_url) . '#' . $hash_route;
        }, 999);

        // Prevent caching
        add_action('template_redirect', function () {
            nocache_headers();
        }, 1);
    }

    /**
     * Redirect WooCommerce pages to SPA routes
     * Maps: /shop → /store/, /cart → /store/cart, etc.
     */
    public static function redirect_wc_pages_to_spa()
    {
        // Get SPA settings
        $appearance_settings = get_option('woonoow_appearance_settings', []);
        $spa_page_id = $appearance_settings['general']['spa_page'] ?? 0;
        $spa_mode = $appearance_settings['general']['spa_mode'] ?? 'full';
        $use_browser_router = $appearance_settings['general']['use_browser_router'] ?? true;
        
        // Only redirect when SPA mode is 'full'
        if ($spa_mode !== 'full') {
            return;
        }
        
        if (!$spa_page_id) {
            return; // No SPA page configured
        }
        
        // Skip if SPA is set as frontpage (serve_spa_for_frontpage_routes handles it)
        $frontpage_id = (int) get_option('page_on_front');
        if ($frontpage_id && $frontpage_id === (int) $spa_page_id) {
            return;
        }
        
        // Already on SPA page, don't redirect
        global $post;
        if ($post && $post->ID == $spa_page_id) {
            return;
        }
        
        $spa_url = trailingslashit(get_permalink($spa_page_id));
        
        // Helper function to build route URL based on router type
        $build_route = function($path) use ($spa_url, $use_browser_router) {
            if ($use_browser_router) {
                // Path format: /store/cart
                return $spa_url . ltrim($path, '/');
            }
            // Hash format: /store/#/cart
            return rtrim($spa_url, '/') . '#/' . ltrim($path, '/');
        };
        
        // Check which WC page we're on and redirect
        if (is_shop()) {
            wp_redirect($build_route('shop'), 302);
            exit;
        }
        
        if (is_product()) {
            // Use get_queried_object() which returns the WP_Post, then get slug
            $product_post = get_queried_object();
            if ($product_post && isset($product_post->post_name)) {
                $slug = $product_post->post_name;
                wp_redirect($build_route('product/' . $slug), 302);
                exit;
            }
        }
        
        if (is_cart()) {
            wp_redirect($build_route('cart'), 302);
            exit;
        }
        
        if (is_checkout() && !is_order_received_page()) {
            wp_redirect($build_route('checkout'), 302);
            exit;
        }
        
        if (is_account_page()) {
            wp_redirect($build_route('my-account'), 302);
            exit;
        }
    }

    /**
     * Serve SPA template directly for frontpage SPA routes
     * When SPA page is set as WordPress frontpage, intercept known routes
     * and serve the SPA template directly (bypasses WooCommerce templates)
     */
    public static function serve_spa_for_frontpage_routes()
    {
        // Get SPA settings
        $appearance_settings = get_option('woonoow_appearance_settings', []);
        $spa_page_id = $appearance_settings['general']['spa_page'] ?? 0;
        $spa_mode = $appearance_settings['general']['spa_mode'] ?? 'full';
        
        // Only run in full SPA mode
        if ($spa_mode !== 'full' || !$spa_page_id) {
            return;
        }
        
        // Check if SPA page is set as WordPress frontpage
        $frontpage_id = (int) get_option('page_on_front');
        if (!$frontpage_id || $frontpage_id !== (int) $spa_page_id) {
            return; // SPA is not frontpage, let normal routing handle it
        }
        
        // Get the current request path
        $request_uri = $_SERVER['REQUEST_URI'] ?? '/';
        $path = parse_url($request_uri, PHP_URL_PATH);
        $path = '/' . trim($path, '/');
        
        // Define SPA routes that should be intercepted when SPA is frontpage
        $spa_routes = [
            '/',           // Frontpage itself
            '/shop',       // Shop page
            '/cart',       // Cart page
            '/checkout',   // Checkout page
            '/my-account', // Account page
            '/login',      // Login page
            '/register',   // Register page
            '/reset-password', // Password reset
        ];
        
        // Check for exact matches or path prefixes
        $should_serve_spa = false;
        
        // Check exact matches
        if (in_array($path, $spa_routes)) {
            $should_serve_spa = true;
        }
        
        // Check path prefixes (for sub-routes)
        $prefix_routes = ['/shop/', '/my-account/', '/product/'];
        foreach ($prefix_routes as $prefix) {
            if (strpos($path, $prefix) === 0) {
                $should_serve_spa = true;
                break;
            }
        }
        
        // Not a SPA route
        if (!$should_serve_spa) {
            return;
        }
        
        // Prevent caching for dynamic SPA content
        nocache_headers();
        
        // Load the SPA template directly and exit
        $spa_template = plugin_dir_path(dirname(dirname(__FILE__))) . 'templates/spa-full-page.php';
        if (file_exists($spa_template)) {
            // Set up minimal WordPress environment for the template
            status_header(200);
            
            // Define constant to tell Assets to load unconditionally
            if (!defined('WOONOOW_SERVE_SPA')) {
                define('WOONOOW_SERVE_SPA', true);
            }
            
            // Include the SPA template
            include $spa_template;
            exit;
        }
    }

    /**
     * Disable canonical redirects for SPA routes
     * This prevents WordPress from redirecting /product/slug URLs
     */
    public static function disable_canonical_redirect($redirect_url, $requested_url)
    {
        $settings = get_option('woonoow_customer_spa_settings', []);
        $mode = isset($settings['mode']) ? $settings['mode'] : 'disabled';

        // Only disable redirects in full SPA mode
        if ($mode !== 'full') {
            return $redirect_url;
        }

        // Check if this is a SPA route
        $spa_routes = ['/product/', '/cart', '/checkout', '/my-account'];

        foreach ($spa_routes as $route) {
            if (strpos($requested_url, $route) !== false) {
                // This is a SPA route, disable WordPress redirect
                return false;
            }
        }

        return $redirect_url;
    }

    /**
     * Use SPA template (blank page)
     */
    public static function use_spa_template($template)
    {
        // Check spa_mode from appearance settings FIRST
        $appearance_settings = get_option('woonoow_appearance_settings', []);
        $spa_mode = $appearance_settings['general']['spa_mode'] ?? 'full';
        
        // If SPA is disabled, return original template immediately
        if ($spa_mode === 'disabled') {
            return $template;
        }
        
        // Check if current page is a designated SPA page
        if (self::is_spa_page()) {
            $spa_template = plugin_dir_path(dirname(dirname(__FILE__))) . 'templates/spa-full-page.php';
            if (file_exists($spa_template)) {
                return $spa_template;
            }
        }

        // For spa_mode = 'full', override WooCommerce pages
        if ($spa_mode === 'full') {
            // Override all WooCommerce pages
            if (is_woocommerce() || is_product() || is_cart() || is_checkout() || is_account_page()) {
                $spa_template = plugin_dir_path(dirname(dirname(__FILE__))) . 'templates/spa-full-page.php';
                if (file_exists($spa_template)) {
                    return $spa_template;
                }
            }
        }
        
        // For spa_mode = 'checkout_only'
        if ($spa_mode === 'checkout_only') {
            if (is_checkout() || is_order_received_page() || is_account_page() || is_cart()) {
                $spa_template = plugin_dir_path(dirname(dirname(__FILE__))) . 'templates/spa-full-page.php';
                if (file_exists($spa_template)) {
                    return $spa_template;
                }
            }
        }

        return $template;
    }

    /**
     * Start SPA wrapper
     */
    public static function start_spa_wrapper()
    {
        // Check if we should use SPA
        if (!self::should_use_spa()) {
            return;
        }

        // Determine page type
        $page_type = 'shop';
        $data_attrs = 'data-page="shop"';

        if (is_product()) {
            $page_type = 'product';
            global $post;
            $data_attrs = 'data-page="product" data-product-id="' . esc_attr($post->ID) . '"';
        } elseif (is_cart()) {
            $page_type = 'cart';
            $data_attrs = 'data-page="cart"';
        } elseif (is_checkout()) {
            $page_type = 'checkout';
            $data_attrs = 'data-page="checkout"';
        } elseif (is_account_page()) {
            $page_type = 'account';
            $data_attrs = 'data-page="account"';
        }

        // Output SPA mount point
        echo '<div id="woonoow-customer-app" ' . $data_attrs . '>';
        echo '<div class="woonoow-loading">';
        echo '<p>' . esc_html__('Loading...', 'woonoow') . '</p>';
        echo '</div>';
        echo '</div>';

        // Hide WooCommerce content
        echo '<div style="display: none;">';
    }

    /**
     * End SPA wrapper
     */
    public static function end_spa_wrapper()
    {
        if (!self::should_use_spa()) {
            return;
        }

        // Close hidden wrapper
        echo '</div>';
    }

    /**
     * Check if we should use SPA
     */
    private static function should_use_spa()
    {
        // Check spa_mode from appearance settings
        $appearance_settings = get_option('woonoow_appearance_settings', []);
        $spa_mode = $appearance_settings['general']['spa_mode'] ?? 'full';

        // Only use SPA when mode is 'full'
        if ($spa_mode !== 'full') {
            return false;
        }

        // For full SPA mode, use SPA on WooCommerce pages
        if (is_shop() || is_product() || is_cart() || is_checkout() || is_account_page()) {
            return true;
        }

        return false;
    }

    /**
     * Remove theme header when SPA is active
     */
    public static function remove_theme_header()
    {
        if (self::should_remove_theme_elements()) {
            remove_all_actions('wp_head');
            // Re-add essential WordPress head actions
            add_action('wp_head', 'wp_enqueue_scripts', 1);
            add_action('wp_head', 'wp_print_styles', 8);
            add_action('wp_head', 'wp_print_head_scripts', 9);
            add_action('wp_head', 'wp_resource_hints', 2);
            add_action('wp_head', 'wp_site_icon', 99);
        }
    }

    /**
     * Remove theme footer when SPA is active
     */
    public static function remove_theme_footer()
    {
        if (self::should_remove_theme_elements()) {
            remove_all_actions('wp_footer');
            // Re-add essential WordPress footer actions
            add_action('wp_footer', 'wp_print_footer_scripts', 20);
        }
    }

    /**
     * Check if current page is the designated SPA page
     */
    private static function is_spa_page()
    {
        global $post;
        
        // Get SPA settings from appearance
        $appearance_settings = get_option('woonoow_appearance_settings', []);
        $spa_page_id = $appearance_settings['general']['spa_page'] ?? 0;
        $spa_mode = $appearance_settings['general']['spa_mode'] ?? 'full';

        // Only check if spa_mode is 'full' and SPA page is configured
        if ($spa_mode !== 'full' || !$spa_page_id) {
            return false;
        }

        // Check if current page is the SPA page
        if ($post && $post->ID == $spa_page_id) {
            return true;
        }

        // Check if SPA page is set as WordPress frontpage and we're on frontpage
        $frontpage_id = (int) get_option('page_on_front');
        if ($frontpage_id && $frontpage_id === (int) $spa_page_id && is_front_page()) {
            return true;
        }

        return false;
    }

    /**
     * Check if we should remove theme header/footer
     */
    private static function should_remove_theme_elements()
    {
        // Remove for designated SPA pages
        if (self::is_spa_page()) {
            return true;
        }

        // Check spa_mode from appearance settings
        $appearance_settings = get_option('woonoow_appearance_settings', []);
        $spa_mode = $appearance_settings['general']['spa_mode'] ?? 'full';

        // Check if we're on a WooCommerce page in full mode
        if ($spa_mode === 'full') {
            if (is_shop() || is_product() || is_cart() || is_checkout() || is_account_page() || is_woocommerce()) {
                return true;
            }
        }

        // When SPA is disabled, don't remove theme elements
        if ($spa_mode === 'disabled') {
            return false;
        }

        return false;
    }

    /**
     * Override WooCommerce templates
     */
    public static function override_template($template, $template_name, $template_path)
    {
        // Only override if SPA is enabled
        if (!self::should_use_spa()) {
            return $template;
        }

        // Templates to override
        $override_templates = [
            'archive-product.php',
            'single-product.php',
            'cart/cart.php',
            'checkout/form-checkout.php',
        ];

        // Check if this template should be overridden
        foreach ($override_templates as $override) {
            if (strpos($template_name, $override) !== false) {
                // Return empty template (SPA will handle rendering)
                return plugin_dir_path(dirname(dirname(__FILE__))) . 'templates/spa-wrapper.php';
            }
        }

        return $template;
    }
}