// ===================================================================
// === ROUTER (V12) - CON SOPORTE PARA TAGS Y HISTÓRICO            ===
// ===================================================================

// 1. SISTEMA DE CACHÉ HTML (SIMPLE)
if ($_SERVER['REQUEST_METHOD'] === 'GET' && !isset($_GET['q'])) {
    $req_slug = trim($_GET['slug'] ?? '', '/');
    if (empty($req_slug)) $req_slug = 'usd';

    // Solo cacheamos páginas "estándar" (Portada, Divisas). 
    // Evitamos cachear búsquedas, tags o URLs complejas aquí para no llenar disco.
    if (preg_match('/^[a-z0-9-]+$/', $req_slug) && !in_array($req_slug, ['news', 'contact', 'search', 'dolar-historico', 'tag'])) {
        $cache_file = __DIR__ . '/cache/html/' . ($req_slug === 'usd' ? 'index' : $req_slug) . '.html';
        if (file_exists($cache_file) && (time() - filemtime($cache_file) < 60)) {
            readfile($cache_file);
            exit;
        }
    }
}

// 2. CONFIGURACIÓN INICIAL
header('Content-Type: text/html; charset=utf-8');
date_default_timezone_set('America/Santiago'); 
ob_start(); // Iniciar buffer de salida
ini_set('display_errors', 0);

$config = require __DIR__ . '/includes/site-config.php';
require_once __DIR__ . '/includes/functions.php';

// Obtener el slug solicitado
$slug = trim($_GET['slug'] ?? '', '/');
if (empty($slug)) $slug = 'usd';
$slug_parts = explode('/', $slug);

// Cargar datos de monedas
$currency_pages = require __DIR__ . '/includes/currency-data.php';
$page_config = null;
$page_data = [];

// ===================================================================
// === ENRUTADOR MAESTRO ===
// ===================================================================

// A. PÁGINAS DE DIVISAS (USD, EUR, UF, ETC.)
if (isset($currency_pages[$slug])) {
    $page_config = $currency_pages[$slug];
    $page_config['current_nav'] = $slug; // Para resaltar en menú
    $page_config['template'] = 'currency-converter-content.php';

    require_once __DIR__ . '/includes/database.php';
    
    // Limpieza de seguridad para nombre de tabla
    $clean_code = preg_replace('/[^a-z0-9_]/', '', $page_config['db_slug'] ?? $slug);
    $table = "valor_dolar_{$clean_code}";
    
    $current_rate = 0;
    $db_timestamp = null;
    $history_data = []; 

    if ($conn) {
        // Traemos los últimos 10 registros para calcular variaciones (ayer, semana)
        $res = $conn->query("SELECT valor, timestamp, fecha FROM {$table} ORDER BY timestamp DESC LIMIT 10");
        
        if ($res && $res->num_rows > 0) {
            $rows = $res->fetch_all(MYSQLI_ASSOC);
            
            // El primero es el actual
            $current_rate = (float)$rows[0]['valor'];
            $db_timestamp = $rows[0]['timestamp'];
            
            // Guardamos todo para cálculos de tendencia
            foreach($rows as $r) {
                $history_data[] = (float)$r['valor'];
            }
        }
		
		// FIX DE SEGURIDAD: Si la DB falló y el precio es 0, intentar leer caché de disco
		if ($current_rate <= 0) {
			$json_cache = __DIR__ . "/cache/prices/price_{$clean_code}.json";
			if (file_exists($json_cache)) {
				$json_data = json_decode(file_get_contents($json_cache), true);
				if (isset($json_data['price'])) {
					$current_rate = (float)$json_data['price'];
				}
			}
		}
    }

    $page_data = [
        'rate' => $current_rate,
        'db_timestamp' => $db_timestamp,
        'history' => $history_data,
        'currency_code' => $clean_code,
        'from_currency' => [
            'name' => $page_config['currency_name'], 
            'singular' => $page_config['currency_name_singular'] ?? 'dólar',
            'plural' => $page_config['currency_name_plural'] ?? 'dólares',
            'code' => strtoupper($page_config['iso_code'] ?? 'USD'),
            'flag' => $page_config['currency_flag'] ?? 'usa.png'
        ]
    ];
}

// B. SECCIÓN DE NOTICIAS (CON FIX DE PAGINACIÓN)
elseif ($slug_parts[0] === 'news') {
    $wp_api = $config['base_url'] . '/blog/wp-json/wp/v2';
    
    // B.1 Noticia Individual (Si hay slug y NO es "page")
    // Ejemplo: /news/titulo-noticia
    if (isset($slug_parts[1]) && $slug_parts[1] !== 'page') {
        $post_slug = htmlspecialchars($slug_parts[1]);
        $resp = fetch_from_api_with_cache("{$wp_api}/posts?slug={$post_slug}&_embed", 3600);
        $post = $resp['body'][0] ?? null;
        
        if ($post) {
            // Limpieza y Corte Inteligente para SEO
            $raw_excerpt = strip_tags($post['excerpt']['rendered']); 
            $raw_excerpt = str_replace(["\r", "\n", "&nbsp;"], " ", $raw_excerpt);
            $raw_excerpt = html_entity_decode($raw_excerpt);
            $raw_excerpt = trim($raw_excerpt);

            $limit = 155; 
            if (mb_strlen($raw_excerpt) > $limit) {
                $sub = mb_substr($raw_excerpt, 0, $limit + 5); 
                $last_space = mb_strrpos($sub, ' ');
                $meta_desc = ($last_space !== false) ? mb_substr($sub, 0, $last_space) . '...' : mb_substr($raw_excerpt, 0, $limit) . '...';
            } else {
                $meta_desc = $raw_excerpt;
            }
            
            $feat_media = $post['_embedded']['wp:featuredmedia'][0] ?? null;
            $img_alt = $feat_media['alt_text'] ?? $post['title']['rendered'];
            if(empty($img_alt)) $img_alt = "Noticia sobre " . $post['title']['rendered'];
            
            $page_config = [
                'template' => 'single-post-content.php', 
                'current_nav' => 'news', 
                'post_data' => $post, 
                'page_title' => $post['title']['rendered'], 
                'description' => $meta_desc, 
                'og_image' => $post['_embedded']['wp:featuredmedia'][0]['source_url'] ?? null, 
                'og_image_alt' => $img_alt 
            ];
        } else {
            $page_config = ['template' => '404-content.php', 'page_title' => 'Noticia no encontrada'];
        }
    } 
    // B.2 Archivo de Noticias (Lista con Paginación)
    // Ejemplo: /news o /news/page/2
    else {
        $current_page = 1;

        // Caso 1: URL tipo /news?page=2
        if (isset($_GET['page'])) {
            $current_page = (int)$_GET['page'];
        }
        // Caso 2: URL tipo /news/page/2
        elseif (isset($slug_parts[1]) && $slug_parts[1] === 'page' && isset($slug_parts[2])) {
            $current_page = (int)$slug_parts[2];
        }

        if ($current_page < 1) $current_page = 1;

        $page_config = [
            'template' => 'archive-content.php', 
            'current_nav' => 'news', 
            'type' => 'news_archive', 
            'breadcrumbs' => [['text'=>'Noticias']], 
            'api_endpoint_count' => "{$wp_api}/posts", 
            'api_endpoint_posts' => "{$wp_api}/posts?_embed", 
            'base_pagination_url' => "/news", 
            'h1_title' => "Noticias Financieras y Económicas",
            'page_title' => "Noticias del Dólar y Economía en Chile | Valor Dólar - Pág $current_page",
            'description' => "Lee las últimas noticias sobre el tipo de cambio, economía chilena y mercado internacional.",
            'current_page' => $current_page 
        ];
    }
}

// G. SECCIÓN DE CATEGORÍAS
elseif ($slug_parts[0] === 'category' && isset($slug_parts[1])) {
    $cat_slug = htmlspecialchars($slug_parts[1]);
    $current_page = 1;

    // --- FIX: DETECTAR PÁGINA EN URL (/category/slug/page/2) ---
    if (isset($slug_parts[2]) && $slug_parts[2] === 'page' && isset($slug_parts[3])) {
        $current_page = (int)$slug_parts[3];
    } elseif (isset($_GET['page'])) {
        $current_page = (int)$_GET['page'];
    }

    if ($current_page < 1) $current_page = 1;

    $wp_api = $config['base_url'] . '/blog/wp-json/wp/v2';
    
    // 1. Obtener ID de la categoría (Cache 1 hora)
    $cat_resp = fetch_from_api_with_cache("{$wp_api}/categories?slug={$cat_slug}", 3600);
    $category_info = $cat_resp['body'][0] ?? null;

    if ($category_info) {
        $cat_id = $category_info['id'];
        $cat_name = $category_info['name'];
        
        $page_config = [
            'template' => 'archive-content.php',
            'current_nav' => 'news',
            'type' => 'category_archive',
            'breadcrumbs' => [
                ['text'=>'Noticias', 'link'=>'/news'], 
                ['text'=>$cat_name]
            ],
            // Endpoints filtrados por categoría
            'api_endpoint_count' => "{$wp_api}/posts?categories={$cat_id}",
            'api_endpoint_posts' => "{$wp_api}/posts?_embed&categories={$cat_id}",
            'base_pagination_url' => "/category/{$cat_slug}",
            'h1_title' => "Noticias de: " . $cat_name,
            'page_title' => "{$cat_name} - Página {$current_page} | Valor Dólar",
            'description' => "Lee las últimas noticias sobre {$cat_name} en Chile y el mundo.",
            'current_page' => $current_page 
        ];
    } else {
        $page_config = ['template' => '404-content.php', 'page_title' => 'Categoría no encontrada'];
    }
}

// ===================================================================
// I. SECCIÓN DE ETIQUETAS (TAGS) - CON FALLBACK INTELIGENTE
// ===================================================================
elseif ($slug_parts[0] === 'tag' && isset($slug_parts[1])) {
    $tag_slug = htmlspecialchars($slug_parts[1]);
    $current_page = 1;

    if (isset($slug_parts[2]) && $slug_parts[2] === 'page' && isset($slug_parts[3])) {
        $current_page = (int)$slug_parts[3];
    } elseif (isset($_GET['page'])) {
        $current_page = (int)$_GET['page'];
    }
    if ($current_page < 1) $current_page = 1;

    $wp_api = $config['base_url'] . '/blog/wp-json/wp/v2';
    
    // 1. Consultar si el TAG existe realmente en WordPress
    $tag_resp = fetch_from_api_with_cache("{$wp_api}/tags?slug={$tag_slug}", 3600);
    $tag_info = $tag_resp['body'][0] ?? null;

    if ($tag_info) {
        // --- CASO A: EL TAG SÍ EXISTE ---
        $tag_id = $tag_info['id'];
        $tag_name = $tag_info['name'];
        
        $page_config = [
            'template' => 'archive-content.php',
            'current_nav' => 'news',
            'type' => 'tag_archive',
            'breadcrumbs' => [
                ['text'=>'Noticias', 'link'=>'/news'], 
                ['text'=>'Etiqueta: ' . $tag_name]
            ],
            'api_endpoint_count' => "{$wp_api}/posts?tags={$tag_id}",
            'api_endpoint_posts' => "{$wp_api}/posts?_embed&tags={$tag_id}",
            'base_pagination_url' => "/tag/{$tag_slug}",
            'h1_title' => "Noticias sobre: " . $tag_name,
            'page_title' => "{$tag_name} (Etiqueta) - Pág {$current_page} | Valor Dólar",
            'description' => "Recopilación de noticias y análisis relacionados con {$tag_name}.",
            'current_page' => $current_page
        ];
    } else {
        // --- CASO B: EL TAG NO EXISTE (FALLBACK MÁGICO) ---
        // En lugar de dar error 404, redirigimos al buscador.
        // Ejemplo: /tag/noticias -> /search?q=noticias
        
        // Limpiamos el slug (quitamos guiones) para buscar mejor
        $clean_query = str_replace('-', ' ', $tag_slug);
        
        header("Location: " . $config['base_url'] . "/search?q=" . urlencode($clean_query), true, 301);
        exit;
    }
}

// C. SECCIÓN HISTÓRICA - PORTADA
elseif ($slug === 'dolar-historico') {
    require_once __DIR__ . '/includes/database.php';
    $years = [];
    if($conn) {
        $res = $conn->query("SELECT DISTINCT YEAR(fecha) as anio FROM valor_dolar_obs ORDER BY anio DESC");
        while($r = $res->fetch_assoc()) $years[] = $r['anio'];
    }
    $page_config = [
        'template' => 'historical-archive.php', 
        'current_nav' => 'dolar-historico', 
        'page_title' => 'Histórico del Dólar en Chile (1984 - Hoy) | Valor Dólar',
        'description' => 'Consulta la base de datos histórica completa del valor del dólar observado en Chile. Tablas anuales, mensuales y calculadora de valores pasados.',
        'view_type' => 'main', 
        'years_list' => $years
    ];
}

// D. SECCIÓN HISTÓRICA - AÑO
elseif ($slug === 'historical-year') {
    require_once __DIR__ . '/includes/database.php';
    $year = (int)($_GET['year'] ?? date('Y'));
    
    $stats = ['avg_val' => 0, 'max_val' => 0];
    if ($conn) {
        $stmt = $conn->prepare("SELECT AVG(valor) as prom, MAX(valor) as max FROM valor_dolar_obs WHERE YEAR(fecha) = ?");
        $stmt->bind_param("i", $year);
        $stmt->execute();
        $res = $stmt->get_result();
        if ($row = $res->fetch_assoc()) {
            $stats['avg_val'] = $row['prom'];
            $stats['max_val'] = $row['max'];
        }
    }

    $seo_prom = number_format($stats['avg_val'], 0, ',', '.');
    $seo_max = number_format($stats['max_val'], 0, ',', '.');

    $page_config = [
        'template' => 'historical-archive.php', 
        'current_nav' => 'dolar-historico',
        'page_title' => "Precio del Dólar año $year en Chile: Resumen y Gráfico",
        'description' => "Resumen del dólar en el año $year. El precio promedio fue de $$seo_prom y alcanzó un máximo de $$seo_max. Revisa la tabla completa día a día.",
        'view_type' => 'year', 
        'data_year' => $year,
        'year_stats' => $stats
    ];
}

// E. SECCIÓN HISTÓRICA - MES
elseif ($slug === 'historical-month') {
    require_once __DIR__ . '/includes/database.php';
    
    $year = (int)($_GET['year'] ?? date('Y'));
    $month_input = strtolower(trim($_GET['month'] ?? ''));
    
    $meses_map = ['enero'=>1, 'febrero'=>2, 'marzo'=>3, 'abril'=>4, 'mayo'=>5, 'junio'=>6, 'julio'=>7, 'agosto'=>8, 'septiembre'=>9, 'octubre'=>10, 'noviembre'=>11, 'diciembre'=>12];
    $month_num = is_numeric($month_input) ? (int)$month_input : ($meses_map[$month_input] ?? 0);

    if ($month_num > 0 && $conn) {
        $query = "SELECT * FROM valor_dolar_obs WHERE YEAR(fecha) = ? AND MONTH(fecha) = ? ORDER BY fecha ASC";
        $stmt = $conn->prepare($query);
        $stmt->bind_param("ii", $year, $month_num);
        $stmt->execute();
        $res = $stmt->get_result();
        
        $data = [];
        $min = 99999; $max = 0; $sum = 0; $count = 0;
        $start_val = 0; $end_val = 0;
        
        while($row = $res->fetch_assoc()) {
            $val = (float)$row['valor'];
            $data[] = ['date' => $row['fecha'], 'val' => $val];
            if ($val < $min) $min = $val;
            if ($val > $max) $max = $val;
            $sum += $val;
            $count++;
            $end_val = $val; 
            if ($start_val == 0) $start_val = $val; 
        }

        $stats = ['min' => ($count > 0)?$min:0, 'max' => $max, 'avg' => ($count > 0)?$sum/$count:0, 'start' => $start_val, 'end' => $end_val];
        $meses_inv = array_flip($meses_map);
        $mes_nombre = ucfirst($meses_inv[$month_num] ?? $month_input);

        $seo_inicio = number_format($stats['start'], 0, ',', '.');
        $seo_fin = number_format($stats['end'], 0, ',', '.');
        $seo_prom = number_format($stats['avg'], 0, ',', '.');

        $page_config = [
            'template' => 'historical-month-report.php',
            'current_nav' => 'dolar-historico',
            'page_title' => "Valor Dólar $mes_nombre $year - Tabla Oficial SII",
            'description' => "En $mes_nombre de $year, el dólar en Chile inició en $$seo_inicio y cerró en $$seo_fin, promediando $$seo_prom. Revisa la variación diaria aquí.",
            'data' => $data,
            'stats' => $stats,
            'report_year' => $year,
            'report_month' => $mes_nombre,
            'month_num' => $month_num
        ];
    } else {
        $page_config = null; 
    }
}

// H. SECCIÓN DE BÚSQUEDA
elseif ($slug === 'search') {
    $query = htmlspecialchars($_GET['q'] ?? '');
    $wp_api = $config['base_url'] . '/blog/wp-json/wp/v2';
    
    $current_page = isset($_GET['page']) ? (int)$_GET['page'] : 1;
    if ($current_page < 1) $current_page = 1;
    
    // Si hay búsqueda, consultamos a WP
    if (!empty($query)) {
        // 1. Obtener TOTAL de resultados
        $count_api = "{$wp_api}/posts?search=" . urlencode($query);
        $ctx = stream_context_create(["http" => ["ignore_errors" => true, "timeout" => 3]]);
        @file_get_contents($count_api, false, $ctx);
        $headers = $http_response_header ?? [];
        $total_pages = 1;
        
        foreach ($headers as $header) {
            if (stripos($header, 'X-WP-TotalPages') !== false) {
                $total_pages = (int)trim(explode(':', $header)[1]);
                break;
            }
        }

        // 2. Obtener los posts
        $search_api = "{$wp_api}/posts?_embed&search=" . urlencode($query) . "&per_page=10&page={$current_page}";
        $search_resp = fetch_from_api_with_cache($search_api, 300);
        $posts = $search_resp['body'] ?? [];
        
        $page_config = [
            'template' => 'archive-content.php',
            'current_nav' => 'news',
            'type' => 'search_results',
            'breadcrumbs' => [['text'=>'Búsqueda']],
            'h1_title' => "Resultados para: " . $query,
            'page_title' => "Búsqueda: {$query} - Pág {$current_page} | Valor Dólar",
            'description' => "Resultados de búsqueda para {$query}.",
            'manual_posts' => $posts,
            'manual_total_pages' => $total_pages, // Pasamos el total calculado
            'current_page' => $current_page,
            'base_pagination_url' => "/search?q=" . urlencode($query) 
        ];
    } else {
        // Búsqueda vacía
        $page_config = [
            'template' => 'archive-content.php',
            'h1_title' => "Búsqueda",
            'page_title' => "Buscar | Valor Dólar",
            'manual_posts' => [],
            'manual_total_pages' => 1
        ];
    }
}

// F. PÁGINAS ESTÁTICAS
elseif (in_array($slug, ['contact', 'privacy-policy', 'about-us', 'mapa-del-sitio'])) {
    $titles = [
        'contact' => 'Contacto', 
        'privacy-policy' => 'Política de Privacidad', 
        'about-us' => 'Nosotros',
        'mapa-del-sitio' => 'Mapa del Sitio'
    ];
    
    $template_file = ($slug === 'mapa-del-sitio') ? 'sitemap-html-content.php' : "{$slug}-content.php";

    $page_config = [
        'template' => $template_file, 
        'current_nav' => $slug,
        'page_title' => $titles[$slug] . ' | Valor Dólar'
    ];
}

// 404 - PÁGINA NO ENCONTRADA
if ($page_config === null) {
    header("HTTP/1.0 404 Not Found");
    $page_config = [
        'template' => '404-content.php', 
        'page_title' => 'Página no encontrada',
        'current_nav' => ''
    ];
}

// ===================================================================
// === RENDERIZADO FINAL ===
// ===================================================================

require_once __DIR__ . '/includes/header.php';

$tpl = __DIR__ . '/templates/' . $page_config['template'];
if(file_exists($tpl)) {
    require_once $tpl;
} else {
    echo "<div class='site-wrapper' style='padding:50px;'>Error: Plantilla no encontrada ($tpl)</div>";
}

require_once __DIR__ . '/includes/footer.php';

// ===================================================================
// === GUARDADO DE CACHÉ ===
// ===================================================================
$html = ob_get_contents();
ob_end_flush();

// Solo guardamos caché de páginas estables
if ($slug === 'usd' || isset($currency_pages[$slug])) {
    $cf = __DIR__ . '/cache/html/' . ($slug === 'usd' ? 'index' : $slug) . '.html';
    if (!is_dir(dirname($cf))) @mkdir(dirname($cf), 0775, true);
    file_put_contents($cf, $html, LOCK_EX);
}
?>