<?php

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

/**
 * Cache Stuffs
 */
/**
 * Update cache timestamps when content is modified
 * This helps us reduce database requests and only update a content cache when necessary
 */
/**
 * @param string $type
 * @param object|null $item
 *
 * @return array
 */
function jvbUpdateCacheTimestamp(string $type, object|null $item = null):array
{
	$timestamps = jvbGetCache();
	$current_time = time();

	// Handle different types of updates
	switch ($type) {
		case 'term':
			// Get term and update its taxonomy timestamp
			$taxonomy = str_replace(BASE, '', $item->taxonomy);
			$timestamps[ $taxonomy ] = $current_time;
			JVBase\managers\CacheManager::invalidateGroup($taxonomy);
			JVBase\managers\CacheManager::invalidateGroup('terms');
			break;

		case 'post':
			// Update specific post type timestamp
			$post_type = str_replace(BASE, '', $item->postType);
			$timestamps[$post_type] = $current_time;
			JVBase\managers\CacheManager::invalidateGroup($post_type);
			break;
		default:
			$timestamps[$type] = $current_time;
			JVBase\managers\CacheManager::invalidateGroup($type);
			break;
	}
	update_option('jvb_cache', $timestamps);
	return $timestamps;
}

// Hook into WordPress content changes
add_action('save_post', function ($post_id, $post, $update) {
	if (jvbNoSaveIt($post_id, $post)) {
		return;
	}
	if (!in_array($post->post_type, jvbBasedFeedContent())) {
		return;
	}
	jvbUpdateCacheTimestamp('post', $post);
}, 10, 3);

add_action('edited_term', function ($term_id, $tt_id, $taxonomy) {
	jvbUpdateCacheTimestamp('term', get_term($term_id, $taxonomy));
}, 10, 3);

add_action('created_term', function ($term_id, $tt_id, $taxonomy) {
	jvbUpdateCacheTimestamp('term', get_term($term_id, $taxonomy));
}, 10, 3);

add_action('rest_api_init', function () {
	register_rest_route('jvb/v1', '/cachedContent', [
		'methods' => 'GET',
		'callback' => 'jvbCacheCheck',
		'permission_callback' => '__return_true' // Public endpoint
	]);
});

function jvbCacheCheck(WP_REST_Request $request):WP_REST_Response
{
	// Get the cache timestamps
	$timestamps = jvbGetCache();

	$data = $request->get_params();
	error_log('Cache request: '.print_r($data, true));

	// Set Last-Modified header for conditional requests
	$last_update = 0;
	foreach ($timestamps as $type) {
		if ($type > $last_update) {
			$last_update = $type;
		}
	}
	if ($last_update > 0) {
		header('Last-Modified: ' . gmdate('D, d M Y H:i:s', $last_update) . ' GMT');
	}

	// Check If-Modified-Since header
	$if_modified_since = $request->get_header('if-modified-since');
	if ($if_modified_since) {
		$if_modified_since = strtotime($if_modified_since);
		if ($last_update <= $if_modified_since) {
			// Return 304 Not Modified if nothing has changed
			return new WP_REST_Response(null, 304);
		}
	}

	// Add cache control headers
	header('Cache-Control: max-age=60, must-revalidate');

	return new WP_REST_Response($timestamps);
}

function jvbGetCache():array
{
	$timestamps = get_option('jvb_cache');
	if (!$timestamps) {
		$timestamps = [];
		$keys = JVB()->registeredContent();
		$currentTime = time();
		foreach ($keys as $key) {
			$timestamps[$key] = $currentTime;
		}
		update_option('jvb_cache', $timestamps);
	}
	return $timestamps;
}