<?php
/**
 * HVAC Route Manager
 *
 * Centralized management of URL routing, redirects, and rewrite rules
 *
 * @package HVAC_Community_Events
 * @since 2.0.0
 */

if (!defined('ABSPATH')) {
    exit;
}

/**
 * HVAC_Route_Manager class
 */
class HVAC_Route_Manager {
    
    /**
     * Instance
     * 
     * @var HVAC_Route_Manager
     */
    private static $instance = null;
    
    /**
     * Legacy redirect mappings
     * 
     * @var array
     */
    private $legacy_redirects = array();
    
    /**
     * Parent page redirects
     * 
     * @var array
     */
    private $parent_redirects = array();
    
    /**
     * Get instance
     * 
     * @return HVAC_Route_Manager
     */
    public static function instance() {
        if (null === self::$instance) {
            self::$instance = new self();
        }
        return self::$instance;
    }
    
    /**
     * Constructor
     */
    private function __construct() {
        $this->define_redirects();
        $this->init_hooks();
    }
    
    /**
     * Define redirect mappings
     * 
     * @return void
     */
    private function define_redirects() {
        // Legacy URL to new URL mappings
        $this->legacy_redirects = array(
            'community-login' => 'training-login',
            'hvac-dashboard' => 'trainer/dashboard',
            'manage-event' => 'trainer/event/manage',
            'trainer-profile' => 'trainer/my-profile',
            'event-summary' => 'trainer/event/summary',
            'email-attendees' => 'trainer/email-attendees',
            'certificate-reports' => 'trainer/certificate-reports',
            'generate-certificates' => 'trainer/generate-certificates',
            'certificate-fix' => 'master-trainer/certificate-fix',
            'hvac-documentation' => 'trainer/documentation',
            'attendee-profile' => 'trainer/attendee-profile',
            'google-sheets' => 'master-trainer/google-sheets',
            'communication-templates' => 'trainer/communication-templates',
            'communication-schedules' => 'trainer/communication-schedules',
            'trainer-registration' => 'trainer/registration',
        );
        
        // Parent pages that redirect to dashboards
        $this->parent_redirects = array(
            'trainer' => 'trainer/dashboard',
            'master-trainer' => 'master-trainer/master-dashboard',
            'master-trainer/dashboard' => 'master-trainer/master-dashboard',  // Redirect old URL to new
        );
        
        // Allow filtering
        $this->legacy_redirects = apply_filters('hvac_legacy_redirects', $this->legacy_redirects);
        $this->parent_redirects = apply_filters('hvac_parent_redirects', $this->parent_redirects);
    }
    
    /**
     * Initialize hooks
     * 
     * @return void
     */
    private function init_hooks() {
        // Register rewrite rules
        add_action('init', array($this, 'register_rewrite_rules'), 5);
        
        // Handle redirects - run very early
        add_action('template_redirect', array($this, 'handle_redirects'), 1);
        
        // Intercept page queries for legacy URLs
        add_action('pre_get_posts', array($this, 'intercept_legacy_page_queries'), 1);
        
        // Register query vars
        add_filter('query_vars', array($this, 'register_query_vars'));
        
        // Handle legacy redirect requests
        add_action('parse_request', array($this, 'handle_legacy_redirect_request'));
        
        // Flush rewrite rules on activation
        add_action('hvac_plugin_activated', array($this, 'flush_rewrite_rules'));
    }
    
    /**
     * Register rewrite rules
     * 
     * @return void
     */
    public function register_rewrite_rules() {
        // Add rewrite rules for legacy URLs
        foreach ($this->legacy_redirects as $legacy => $new) {
            add_rewrite_rule(
                '^' . $legacy . '/?$',
                'index.php?hvac_legacy_redirect=' . $legacy,
                'top'
            );
        }
        
        // Add rewrite rules for hierarchical URLs
        // IMPORTANT: Only add rules for pages that don't exist as actual WordPress pages
        // Exclude 'manage' from the event subpage rule since it's a real page
        $hierarchical_rules = array(
            // Only add rules for event subpages that aren't real pages (exclude 'manage')
            'trainer/event/(?!manage)([^/]+)/?$' => 'index.php?hvac_route=trainer&hvac_page=event&hvac_subpage=$matches[1]',
        );
        
        foreach ($hierarchical_rules as $regex => $redirect) {
            add_rewrite_rule($regex, $redirect, 'top');
        }
        
        // Log registration
        HVAC_Logger::info('Registered ' . count($this->legacy_redirects) . ' legacy redirects and ' . count($hierarchical_rules) . ' hierarchical rules', 'Routes');
    }
    
    /**
     * Register query vars
     * 
     * @param array $vars Query vars
     * @return array
     */
    public function register_query_vars($vars) {
        $vars[] = 'hvac_legacy_redirect';
        $vars[] = 'hvac_route';
        $vars[] = 'hvac_page';
        $vars[] = 'hvac_subpage';
        
        return $vars;
    }
    
    /**
     * Handle legacy redirect requests
     * 
     * @param WP $wp WordPress environment instance
     * @return void
     */
    public function handle_legacy_redirect_request($wp) {
        if (!isset($wp->query_vars['hvac_legacy_redirect'])) {
            return;
        }
        
        $legacy_slug = $wp->query_vars['hvac_legacy_redirect'];
        
        if (isset($this->legacy_redirects[$legacy_slug])) {
            $new_url = home_url('/' . $this->legacy_redirects[$legacy_slug] . '/');
            
            // Preserve query parameters
            if (!empty($_SERVER['QUERY_STRING'])) {
                $new_url .= '?' . $_SERVER['QUERY_STRING'];
            }
            
            // Log redirect
            HVAC_Logger::info("Redirecting legacy URL: {$legacy_slug} to {$new_url}", 'Routes');
            
            wp_redirect($new_url, 301);
            exit;
        }
    }
    
    /**
     * Handle redirects
     * 
     * @return void
     */
    public function handle_redirects() {
        // Get current URL path
        $current_path = trim(parse_url($_SERVER['REQUEST_URI'], PHP_URL_PATH), '/');
        
        // Handle legacy redirects
        if (isset($this->legacy_redirects[$current_path])) {
            $this->perform_redirect($this->legacy_redirects[$current_path]);
        }
        
        // Handle parent page redirects
        if (isset($this->parent_redirects[$current_path])) {
            $this->perform_redirect($this->parent_redirects[$current_path]);
        }
        
        // Also check if this is a 404 that should redirect
        if (is_404()) {
            // Check without trailing slash
            $path_no_slash = rtrim($current_path, '/');
            if (isset($this->legacy_redirects[$path_no_slash])) {
                $this->perform_redirect($this->legacy_redirects[$path_no_slash]);
            }
            
            // Check with just the last segment (for pages that might exist but shouldn't)
            $segments = explode('/', $current_path);
            $last_segment = end($segments);
            if ($last_segment && isset($this->legacy_redirects[$last_segment])) {
                $this->perform_redirect($this->legacy_redirects[$last_segment]);
            }
        }
        
        // Also check if this is a page that exists with a legacy slug
        global $post;
        if (is_page() && $post) {
            $current_slug = $post->post_name;
            
            if (isset($this->legacy_redirects[$current_slug])) {
                $this->perform_redirect($this->legacy_redirects[$current_slug]);
            }
        }
    }
    
    /**
     * Perform redirect
     * 
     * @param string $target Target path
     * @return void
     */
    private function perform_redirect($target) {
        // Get current URL
        $current_url = (isset($_SERVER['HTTPS']) && $_SERVER['HTTPS'] === 'on' ? "https" : "http") . "://$_SERVER[HTTP_HOST]$_SERVER[REQUEST_URI]";
        
        $new_url = home_url('/' . $target . '/');
        
        // Preserve query parameters
        if (!empty($_SERVER['QUERY_STRING'])) {
            $new_url .= '?' . $_SERVER['QUERY_STRING'];
        }
        
        // Don't redirect if we're already at the target URL
        if (rtrim($current_url, '/') === rtrim($new_url, '/')) {
            return;
        }
        
        // Log redirect
        HVAC_Logger::info("Performing redirect to: {$new_url}", 'Routes');
        
        wp_redirect($new_url, 301);
        exit;
    }
    
    /**
     * Get legacy redirects
     * 
     * @return array
     */
    public function get_legacy_redirects() {
        return $this->legacy_redirects;
    }
    
    /**
     * Get parent redirects
     * 
     * @return array
     */
    public function get_parent_redirects() {
        return $this->parent_redirects;
    }
    
    /**
     * Add custom redirect
     * 
     * @param string $from From path
     * @param string $to To path
     * @param string $type Type of redirect (legacy or parent)
     * @return void
     */
    public function add_redirect($from, $to, $type = 'legacy') {
        if ($type === 'legacy') {
            $this->legacy_redirects[$from] = $to;
        } elseif ($type === 'parent') {
            $this->parent_redirects[$from] = $to;
        }
        
        // Re-register rules if already initialized
        if (did_action('init')) {
            $this->register_rewrite_rules();
            flush_rewrite_rules();
        }
    }
    
    /**
     * Remove redirect
     * 
     * @param string $from From path
     * @param string $type Type of redirect (legacy or parent)
     * @return void
     */
    public function remove_redirect($from, $type = 'legacy') {
        if ($type === 'legacy' && isset($this->legacy_redirects[$from])) {
            unset($this->legacy_redirects[$from]);
        } elseif ($type === 'parent' && isset($this->parent_redirects[$from])) {
            unset($this->parent_redirects[$from]);
        }
        
        // Re-register rules if already initialized
        if (did_action('init')) {
            $this->register_rewrite_rules();
            flush_rewrite_rules();
        }
    }
    
    /**
     * Flush rewrite rules
     * 
     * @return void
     */
    public function flush_rewrite_rules() {
        flush_rewrite_rules();
        HVAC_Logger::info('Flushed rewrite rules', 'Routes');
    }
    
    /**
     * Check if URL needs redirect
     * 
     * @param string $url URL to check
     * @return string|false Redirect target or false
     */
    public function needs_redirect($url) {
        $path = trim(parse_url($url, PHP_URL_PATH), '/');
        
        if (isset($this->legacy_redirects[$path])) {
            return $this->legacy_redirects[$path];
        }
        
        if (isset($this->parent_redirects[$path])) {
            return $this->parent_redirects[$path];
        }
        
        return false;
    }
    
    /**
     * Intercept page queries for legacy URLs
     * 
     * This prevents WordPress from finding pages with legacy slugs
     * and allows our redirects to work properly
     * 
     * @param WP_Query $query The WordPress query object
     * @return void
     */
    public function intercept_legacy_page_queries($query) {
        // Only run on the main query on the frontend
        if (!$query->is_main_query() || is_admin()) {
            return;
        }
        
        // Check if this is a page query
        if (!$query->is_page()) {
            return;
        }
        
        // Get the page name being queried
        $pagename = $query->get('pagename');
        if (empty($pagename)) {
            return;
        }
        
        // Check if this is a legacy URL that should redirect
        if (isset($this->legacy_redirects[$pagename])) {
            // Prevent WordPress from finding this page
            $query->set('page_id', -1);
            $query->set('pagename', '');
            
            // Force a 404 which will trigger our template_redirect
            $query->set_404();
            
            // Log for debugging
            HVAC_Logger::info("Intercepted legacy page query: {$pagename}", 'Routes');
        }
    }
}