<?php
if (!defined('ABSPATH')) {
    exit;
}

class Beep_Likes {

    public static function init() {
        add_action('rest_api_init', [__CLASS__, 'register_routes']);
    }

    public static function table_name() {
        global $wpdb;
        return $wpdb->prefix . BEEP_LIKES_TABLE;
    }

    /**
     * Create or migrate the likes table.
     * The 'post_id' column historically only stored beep IDs; we now also
     * use it for comment IDs (replies). 'object_type' distinguishes them.
     */
    public static function create_table() {
        global $wpdb;
        $table   = self::table_name();
        $charset = $wpdb->get_charset_collate();

        $sql = "CREATE TABLE $table (
            id BIGINT(20) UNSIGNED NOT NULL AUTO_INCREMENT,
            object_type VARCHAR(20) NOT NULL DEFAULT 'post',
            post_id BIGINT(20) UNSIGNED NOT NULL,
            user_id BIGINT(20) UNSIGNED NOT NULL,
            created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
            PRIMARY KEY  (id),
            UNIQUE KEY object_user (object_type, post_id, user_id),
            KEY post_id (post_id),
            KEY user_id (user_id)
        ) $charset;";

        require_once ABSPATH . 'wp-admin/includes/upgrade.php';
        dbDelta($sql);

        // Migration for installs from v1.0-1.3: add object_type column if missing.
        $col = $wpdb->get_var($wpdb->prepare(
            "SHOW COLUMNS FROM `$table` LIKE %s", 'object_type'
        ));
        if (!$col) {
            $wpdb->query("ALTER TABLE `$table` ADD COLUMN object_type VARCHAR(20) NOT NULL DEFAULT 'post' AFTER id");
        }
    }

    public static function register_routes() {
        // Like a beep (post).
        register_rest_route('beep/v1', '/like/(?P<id>\d+)', [
            'methods'             => 'POST',
            'callback'            => [__CLASS__, 'toggle_post_like'],
            'permission_callback' => [__CLASS__, 'can_interact'],
        ]);

        // Like a reply (comment).
        register_rest_route('beep/v1', '/reply-like/(?P<id>\d+)', [
            'methods'             => 'POST',
            'callback'            => [__CLASS__, 'toggle_reply_like'],
            'permission_callback' => [__CLASS__, 'can_interact'],
        ]);
    }

    public static function can_interact() {
        return is_user_logged_in() && !beep_user_is_banned(get_current_user_id());
    }

    public static function toggle_post_like($request) {
        $id = (int) $request['id'];
        if (get_post_type($id) !== Beep_CPT::POST_TYPE) {
            return new WP_Error('beep_not_a_beep', 'Not a beep.', ['status' => 400]);
        }
        return rest_ensure_response(self::toggle($id, 'post'));
    }

    public static function toggle_reply_like($request) {
        $id = (int) $request['id'];
        $c = get_comment($id);
        if (!$c || get_post_type($c->comment_post_ID) !== Beep_CPT::POST_TYPE) {
            return new WP_Error('beep_not_a_reply', 'Not a reply.', ['status' => 400]);
        }
        return rest_ensure_response(self::toggle($id, 'reply'));
    }

    /**
     * Toggle a like for current user on the given object.
     * @return array {liked: bool, count: int}
     */
    public static function toggle($object_id, $object_type) {
        global $wpdb;
        $table   = self::table_name();
        $user_id = get_current_user_id();

        $existing = $wpdb->get_var($wpdb->prepare(
            "SELECT id FROM $table WHERE object_type = %s AND post_id = %d AND user_id = %d",
            $object_type, $object_id, $user_id
        ));

        if ($existing) {
            $wpdb->delete($table, ['id' => $existing], ['%d']);
            $liked = false;
        } else {
            $wpdb->insert($table, [
                'object_type' => $object_type,
                'post_id'     => $object_id,
                'user_id'     => $user_id,
                'created_at'  => current_time('mysql'),
            ], ['%s', '%d', '%d', '%s']);
            $liked = true;
        }

        return [
            'liked' => $liked,
            'count' => self::get_count($object_id, $object_type),
        ];
    }

    public static function get_count($object_id, $object_type = 'post') {
        global $wpdb;
        $table = self::table_name();
        return (int) $wpdb->get_var($wpdb->prepare(
            "SELECT COUNT(*) FROM $table WHERE object_type = %s AND post_id = %d",
            $object_type, $object_id
        ));
    }

    public static function user_has_liked($object_id, $object_type = 'post', $user_id = null) {
        global $wpdb;
        if (!$user_id) {
            $user_id = get_current_user_id();
        }
        if (!$user_id) {
            return false;
        }
        $table = self::table_name();
        return (bool) $wpdb->get_var($wpdb->prepare(
            "SELECT id FROM $table WHERE object_type = %s AND post_id = %d AND user_id = %d",
            $object_type, $object_id, $user_id
        ));
    }
}