<?php
namespace JVBase\rest;

use JVBase\JVB;
use JVBase\rest\RateLimiter;
use JVBase\managers\OperationQueue;
use JVBase\managers\CacheManager;
use JVBase\managers\NotificationManager;
use WP_REST_Request;
use WP_Error;
use Exception;
use WP_REST_Response;

if (!defined('ABSPATH')) {
    exit; // Exit if accessed directly
}

/**
 * Handles route registration and high-level coordination
 */
abstract class RestRouteManager
{
    protected string $namespace = 'jvb/v1';

    protected RateLimiter|null $rate_limiter;
    protected array $types;
    protected string $route;
    protected string $base;
    protected string $content_type; //the registered post type
    protected string $type; //post, user, term, for MetaManager
    protected string $action = ''; //optional additional nonce to check
    protected array $callback; //route->callback array
    protected string $operation_type; // from QueueManager.js and OperationQueue.php
    protected OperationQueue $queue;
    protected CacheManager $cache;
    protected NotificationManager $notifications;
    protected string $cache_name ='';
    protected int $cache_ttl = 3600; //1 hour default


    // Error code constants for consistency
    const ERROR_MISSING_PARAMS = 'missing_parameters';
    const ERROR_ACCESS_DENIED = 'access_denied';
    const ERROR_NOT_FOUND = 'not_found';
    const ERROR_INVALID_OPERATION = 'invalid_operation';
    const ERROR_PROCESSING = 'processing_error';

    public function __construct()
    {
        $this->base = BASE;
        $this->rate_limiter = new RateLimiter();
        if ($this->cache_name !== '') {
            $this->cache = CacheManager::for($this->cache_name, $this->cache_ttl);
        }
        add_action('rest_api_init', [$this, 'registerRoutes']);
    }

    public function init()
    {
        //Replace in child classes, if necessary
    }


    /**
     * @param WP_REST_Request $request Rest Request object
     * @param string $nonceName nonce name to check
     * @param string|null $nonce optional additional nonce to check
     *
     * @return void|WP_Error
     */
    public function verifyNonce(WP_REST_Request $request, string $nonceName = 'wp_rest', string|null $nonce = null):mixed
    {
        $nonce = (!is_null($nonce)) ? $nonce :  $request->get_header('X-WP-Nonce');

        if (!wp_verify_nonce($nonce, $nonceName)) {
            return new WP_Error(
                'invalid_nonce',
                'Invalid nonce',
                ['status' => 403]
            );
        }
        return true;
    }

    abstract public function registerRoutes();


    /**
     * @param WP_REST_Request $request the Request Object
     *
     * @return bool|WP_Error Whether or not we can proceed
     */
    public function checkPermission(WP_REST_Request $request):bool
    {
        // Check rate limits first
        if (!$this->rate_limiter->checkLimit($request)) {
			error_log('Rate Limit Reached');
            return new WP_Error(
                'rate_limit_reached',
                'Rate limit reached',
                ['status' => 403]
            );
        }
        $user_id = $request->get_param('user');
        if (!empty($user_id) && !$this->userCheck($user_id)) {
			error_log('Usercheck failed');
            return false;
        }
        // Verify nonces
        $this->verifyNonce($request, 'wp_rest');
        if ($this->action!=='') {
            $this->verifyNonce($request, $this->action . $user_id, $request->get_header('action_nonce'));
        }
        return true;
    }

	protected function checkContent(string $content, bool $bool = false):string|bool
	{
		$result = JVB_CONTENT[$content]??JVB_TAXONOMY[$content]??JVB_USER[$content]??'';
		if ($bool) {
			return $result !== '';
		}
		return $result;
	}


    public function formatError($code, $message, $status = 400)
    {
        return new WP_Error($code, $message, ['status' => $status]);
    }

    /**
     * @param int $userID the userID to check
     *
     * @return bool whether or not the $userID matches the currently logged in user
     */
    protected function userCheck(int $userID)
    {
        return $userID === get_current_user_id();
    }

    /**
     * Makes sure the value is in the format it needs to be
     * @param mixed $value
     *
     * @return mixed
     */
    protected function getMetaValues(mixed $value):mixed
    {
        //get the repeater out of there
        $temp = json_decode($value);
        if (is_array($temp)) {
            $value = [];
            foreach ($temp as $t) {
                if (is_object($t)) {
                    $t = (array)$t;
                }
                $value[] = $t;
            }
        }
        return $value;
    }
    /**
     * Log errors with proper context
     * @param string $message The error message
     * @param array $context Additional context
     * @param string $severity
     * @return void
     */
    protected function logError(string $message, array $context = [], string $severity = 'error')
    {
        try {
            JVB()->error()->log(
                'artist_invitations', // component
                $message,
                $context,
                $severity
            );
        } catch (Exception $e) {
            // Fallback if error handler fails
            error_log("Invitations Error: {$message} - " . json_encode($context));
        }
    }

	/**
	 * Check if user exists (cached)
	 */
	protected function checkUser(int $userID): bool
	{
		$cache = CacheManager::for('users');

		return $cache->remember("user_exists_{$userID}", function() use ($userID) {
			return (bool)get_userdata($userID);
		}, DAY_IN_SECONDS);
	}

	/**
	 * Check if shop exists (cached)
	 */
	protected function checkShop(int $shopID): bool
	{
		$cache = CacheManager::for('shop');

		return $cache->remember("shop_exists_{$shopID}", function() use ($shopID) {
			return (bool)term_exists($shopID, BASE . 'shop');
		}, DAY_IN_SECONDS);
	}

	/**
	 * Check if term exists (cached)
	 */
	protected function checkTerm(array $args): bool
	{
		$termID = $args['to_term'] ?? $args['term_id'] ?? false;
		if (!$termID) {
			return false;
		}

		$taxonomy = $args['taxonomy'] ?? false;
		if (!$taxonomy) {
			return false;
		}

		$taxonomy = jvbCheckBase($taxonomy);
		$cache = CacheManager::for($taxonomy);

		return $cache->remember("term_exists_{$termID}", function() use ($termID, $taxonomy) {
			return (bool)term_exists($termID, $taxonomy);
		}, DAY_IN_SECONDS);
	}

	/**
	 * Check if an artist is verified
	 */
	public function isVerifiedUser(int $user_id): bool
	{
		$cache = CacheManager::forUser($user_id);

		return $cache->remember('is_verified', function() use ($user_id) {
			return user_can($user_id, 'skip_moderation');
		}, DAY_IN_SECONDS);
	}

    protected function applyTaxonomyFilters(array $args, array $data):array
    {
        $taxQuery = [];
		foreach($data['taxonomies']??[] as $taxonomy => $terms) {
			if (array_key_exists(jvbNoBase($taxonomy), JVB_TAXONOMY)) {
				$taxQuery[] = [
					'taxonomy'	=> jvbCheckBase($taxonomy),
					'terms'		=> array_map(
						'absint',
						is_array($terms) ? $terms : explode(',', $terms)
					)
				];
			}
		}

        if (!empty($taxQuery)) {
            $args['tax_query'] = array_merge([
                'relation'  => (array_key_exists('match', $data)) ? 'AND' : 'OR',
            ], $taxQuery);
        }

        $authorQuery = [];
        foreach (jvbAuthorUsers() as $type) {
            if (array_key_exists($type, $data)) {
                $artist_ids = array_map(
                    'absint',
                    is_array($data[$type]) ?
                        $data[$type] :
                        explode(',', $data[$type])
                );
                $authorQuery = array_merge($authorQuery, $artist_ids);
            }
        }
        if (!empty($authorQuery)) {
            $args['author__in'] = array_unique($authorQuery);
        }

        return $args;
    }

    protected function applyOrderFilters(array $args, array $data):array
    {
        if (array_key_exists('orderby', $data) && $data['orderby'] === 'random') {
            $current_seed = jvbGetRandomSeed();
            $args['orderby'] = 'RAND(' . $current_seed . ')';
            unset($args['order']);
            return $args;
        }
        if (in_array($data['orderby'], ['date', 'title', 'alphabetical'])) {
            $args['orderby'] = ($data['orderby'] === 'alphabetical') ? 'title' : $data['orderby'];
        } else {
            switch ($data['orderby']) {
                case 'popularity':
                    $args['meta_key'] = BASE.'upvotes';
                    $args['orderby'] = 'meta_value_num';
                    break;
                case 'karma':
                    $args['meta_key'] = BASE.'karma';
                    $args['orderby'] = 'meta_value_num';
                    break;
                default:
                    $args['orderby'] = 'date';
            }
        }
		$order = (array_key_exists('order', $data)) ? strtoupper($data['order']) : 'DESC';
        $args['order'] = (in_array($order, ['ASC', 'DESC'])) ? $order : 'DESC';

        return $args;
    }

    protected function applyDateFilters(array $args, array $data):array
    {
        if (!array_key_exists('date-filter', $data) && !array_key_exists('dateFrom', $data)) {
            return $args;
        }
        if (array_key_exists('dateFrom', $data)) {
            $dateFrom = strtotime(sanitize_text_field($data['dateFrom']));
            $dateTo = strtotime(sanitize_text_field($data['dateTo']));
            if ($dateFrom && $dateTo) {
                $args['date_query'] = [
                    [
                        'after'     => date('c', $dateFrom),
                        'before'    => date('c', $dateTo),
                        'inclusive' => true,
                    ]
                ];
            }
        } else {
            switch ($data['date-filter']) {
                case 'today':
                    $args['date_query'] = [['after' => '1 day ago']];
                    break;
                case 'week':
                    $args['date_query'] = [['after' => '1 week ago']];
                    break;
                case 'month':
                    $args['date_query'] = [['after' => '1 month ago']];
                    break;
                case 'year':
                    $args['date_query'] = [['after' => '1 year ago']];
                    break;
            }
        }
        return $args;
    }

	protected function applyCalendarFilters(array $args, array $data):array
	{
		$meta_query = [];
		$today = date('Y-m-d');
		if (in_array('future', $args['post_status'])) {
			$meta_query[] = [
				'key'	=> 'jvb_start_date',
				'value'	=> $today,
				'compare'	=> '>=',
				'type'	=> 'DATE'
			];
		}
		if (in_array('past', $args['post_status'])) {
			$meta_query[] = [
				'key' => 'jvb_end_date',
				'value' => $today,
				'compare' => '<',
				'type' => 'DATE'
			];
		}
		if (in_array('recurring', $args['post_status'])) {
			$meta_query[] = [
				'key' => 'jvb_is_recurring',
				'value' => true,
				'compare' => '='
			];
		}
		if (!empty($meta_query)) {
			$args['meta_query'] = (array_key_exists('meta_query', $args)) ? array_merge($args['meta_query'], $meta_query) : $meta_query;
		}
		return $args;

	}

	protected function table_exists($tableName, $wpdb = null)
	{
		if (!$wpdb) {
			global $wpdb;
		}
		return $wpdb->get_var("SHOW TABLES LIKE '{$tableName}'") !== $tableName;
	}

	// ========== HTTP CACHING METHODS ==========

	/**
	 * Check HTTP caching headers (ETag and If-Modified-Since)
	 * Returns 304 Not Modified if content hasn't changed
	 *
	 * @param WP_REST_Request $request The REST request
	 * @param string|array $content_types Content type(s) to check timestamps for
	 * @param array $additional_params Additional params for ETag uniqueness (e.g., user_id, filters)
	 * @return WP_REST_Response|null Returns 304 response if not modified, null to continue processing
	 */
	protected function checkHeaders(
		WP_REST_Request $request,
		string|array $content_types,
		array $additional_params = []
	): WP_REST_Response|null {

		// Get latest timestamp for the content type(s)
		$last_modified = CacheManager::getTimestamp($content_types);

		// Generate ETag from request params + timestamp
		$etag = $this->generateETag($request->get_params(), $additional_params, $last_modified);

		// Check If-None-Match (ETag) header
		$if_none_match = $request->get_header('If-None-Match');
		if ($if_none_match === $etag) {
			return $this->createNotModifiedResponse($etag, $last_modified);
		}

		// Check If-Modified-Since header
		$if_modified_since = $request->get_header('If-Modified-Since');
		if ($if_modified_since) {
			$if_modified_timestamp = strtotime($if_modified_since);
			if ($last_modified <= $if_modified_timestamp) {
				return $this->createNotModifiedResponse($etag, $last_modified);
			}
		}

		// Content has changed - store headers to add to successful response
		$this->response_headers = $this->buildCacheHeaders($etag, $last_modified);

		return null; // Continue processing
	}

	/**
	 * Generate ETag from request parameters and timestamp
	 *
	 * @param array $params Request parameters
	 * @param array $additional Additional parameters for uniqueness
	 * @param int $timestamp Last modified timestamp
	 * @return string ETag value with quotes
	 */
	private function generateETag(array $params, array $additional, int $timestamp): string
	{
		// Combine all data that makes this response unique
		$etag_data = array_merge(
			$params,
			$additional,
			['t' => $timestamp]
		);

		return '"' . md5(serialize($etag_data)) . '"';
	}

	/**
	 * Create 304 Not Modified response with proper headers
	 *
	 * @param string $etag ETag value
	 * @param int $last_modified Last modified timestamp
	 * @return WP_REST_Response 304 response
	 */
	private function createNotModifiedResponse(string $etag, int $last_modified): WP_REST_Response
	{
		$response = new WP_REST_Response(null, 304);
		$response->set_headers($this->buildCacheHeaders($etag, $last_modified));
		return $response;
	}

	/**
	 * Build cache headers array
	 *
	 * @param string $etag ETag value
	 * @param int $last_modified Last modified timestamp
	 * @return array Headers array
	 */
	private function buildCacheHeaders(string $etag, int $last_modified): array
	{
		return [
			'ETag' => $etag,
			'Last-Modified' => gmdate('D, d M Y H:i:s', $last_modified) . ' GMT',
			'Cache-Control' => 'private, max-age=60, must-revalidate'
		];
	}

	/**
	 * Add stored cache headers to a response
	 * Call this on your final WP_REST_Response before returning
	 *
	 * @param WP_REST_Response $response The response to add headers to
	 * @return WP_REST_Response The response with headers added
	 */
	protected function addCacheHeaders(WP_REST_Response $response): WP_REST_Response
	{
		if (!empty($this->response_headers)) {
			$response->set_headers($this->response_headers);
			$this->response_headers = []; // Clear after use
		}
		return $response;
	}

	/**
	 * Helper: Check headers for user-specific endpoints
	 * Automatically includes user_id in ETag
	 *
	 * @param WP_REST_Request $request The REST request
	 * @param int $user_id User ID
	 * @param string|array $content_types Content type(s)
	 * @return WP_REST_Response|null
	 */
	protected function checkUserHeaders(
		WP_REST_Request $request,
		int $user_id,
		string|array $content_types = 'user'
	): WP_REST_Response|null {

		// Include user-specific timestamp
		$types = is_array($content_types) ? $content_types : [$content_types];
		$types[] = "user_{$user_id}";

		return $this->checkHeaders($request, $types, ['user_id' => $user_id]);
	}
}
//
//Simple example:
//public function getTattoos(WP_REST_Request $request): WP_REST_Response
//{
//	// Check HTTP cache headers first
//	$cache_check = $this->checkHeaders($request, 'tattoo');
//	if ($cache_check) {
//		return $cache_check; // Returns 304 Not Modified
//	}
//
//	// Get data (use CacheManager for data caching too!)
//	$filters = $request->get_params();
//	$cache = CacheManager::for('tattoo');
//
//	$tattoos = $cache->remember($filters, function() use ($filters) {
//		return $this->queryTattoos($filters);
//	}, 300);
//
//	$response = new WP_REST_Response(['items' => $tattoos]);
//	return $this->addCacheHeaders($response); // Add ETag and Last-Modified
//}
//
//Multiple Content Types:
//public function getTermsWithContent(WP_REST_Request $request): WP_REST_Response
//{
//	$taxonomy = $request->get_param('taxonomy');
//
//	// Check both taxonomy and its content types
//	$cache_check = $this->checkHeaders($request, [$taxonomy, 'tattoo', 'artwork']);
//	if ($cache_check) {
//		return $cache_check;
//	}
//
//	// ... fetch data ...
//
//	$response = new WP_REST_Response($data);
//	return $this->addCacheHeaders($response);
//}
//
//User-specific:
//public function getUserFavorites(WP_REST_Request $request): WP_REST_Response
//{
//	$user_id = $request->get_param('user');
//
//	// Automatically checks user_{$user_id} timestamp + includes user_id in ETag
//	$cache_check = $this->checkUserHeaders($request, $user_id);
//	if ($cache_check) {
//		return $cache_check;
//	}
//
//	// Get user's favorites (cached per user)
//	$favorites = CacheManager::forUser($user_id)->remember('favorites', function() use ($user_id) {
//		return $this->getUserFavorites($user_id);
//	}, 1800);
//
//	$response = new WP_REST_Response(['items' => $favorites]);
//	return $this->addCacheHeaders($response);
//}
//
//Complex with additional params:
//public function getFilteredContent(WP_REST_Request $request): WP_REST_Response
//{
//	$user_id = get_current_user_id();
//	$filters = $request->get_params();
//
//	// Include custom params in ETag for uniqueness
//	$cache_check = $this->checkHeaders(
//		$request,
//		'tattoo',
//		[
//			'user_id' => $user_id,
//			'is_verified' => $this->isVerifiedUser($user_id)
//		]
//	);
//
//	if ($cache_check) {
//		return $cache_check;
//	}
//
//	// ... fetch filtered data ...
//
//	$response = new WP_REST_Response($data);
//	return $this->addCacheHeaders($response);
//}