<?php
/**
 * AKSRT Revenue — 收益台账
 *
 * 管理用户收益记录、结算和统计。
 *
 * @package AKSRT
 */

defined('ABSPATH') || exit;

class AKSRT_Revenue {

    private static $instance = null;

    public static function get_instance(): self {
        if (null === self::$instance) self::$instance = new self();
        return self::$instance;
    }

    private function table(): string {
        return AKSRT_DB_Migrator::table('revenue');
    }

    /**
     * 记录收益
     */
    public function add(int $user_id, float $amount, string $order_number = '', string $type = 'income'): int {
        global $wpdb;

        if ($user_id <= 0 || $amount <= 0) return 0;

        $wpdb->insert($this->table(), [
            'user_id'      => $user_id,
            'order_number' => sanitize_text_field($order_number),
            'amount'       => $amount,
            'type'         => sanitize_key($type),
            'status'       => 'pending',
            'created_at'   => current_time('mysql'),
        ], ['%d', '%s', '%f', '%s', '%s', '%s']);

        return (int) $wpdb->insert_id;
    }

    /**
     * 结算收益
     */
    public function settle(int $revenue_id): bool {
        global $wpdb;

        return $wpdb->update(
            $this->table(),
            ['status' => 'settled', 'settled_at' => current_time('mysql')],
            ['id' => $revenue_id, 'status' => 'pending'],
            ['%s', '%s'],
            ['%d', '%s']
        ) !== false;
    }

    /**
     * 获取用户收益列表
     */
    public function get_user_revenues(int $user_id, array $args = []): array {
        global $wpdb;

        $where = ['user_id = %d'];
        $params = [$user_id];

        $status = sanitize_key((string) ($args['status'] ?? ''));
        if ($status !== '') {
            $where[] = 'status = %s';
            $params[] = $status;
        }

        $limit  = max(1, min(100, (int) ($args['limit'] ?? 20)));
        $offset = max(0, (int) ($args['offset'] ?? 0));

        $sql = "SELECT * FROM {$this->table()} WHERE " . implode(' AND ', $where) . " ORDER BY created_at DESC LIMIT %d OFFSET %d";
        $params[] = $limit;
        $params[] = $offset;

        return (array) $wpdb->get_results($wpdb->prepare($sql, $params), ARRAY_A);
    }

    /**
     * Admin list (all users) with optional status filter.
     *
     * @param array{status?:string,limit?:int,offset?:int} $args
     * @return array{items:array<int,array>,total:int,page:int,max_pages:int}
     */
    public function get_list(array $args = []): array {
        global $wpdb;

        $limit  = max(1, min(100, (int) ($args['limit'] ?? 20)));
        $offset = max(0, (int) ($args['offset'] ?? 0));
        $status = sanitize_key((string) ($args['status'] ?? ''));

        $where  = [];
        $params = [];
        if ($status !== '') {
            $where[]  = 'status = %s';
            $params[] = $status;
        }
        $where_sql = $where ? 'WHERE ' . implode(' AND ', $where) : '';

        $count_sql = "SELECT COUNT(*) FROM {$this->table()} {$where_sql}";
        $total     = $params
            ? (int) $wpdb->get_var($wpdb->prepare($count_sql, $params))
            : (int) $wpdb->get_var($count_sql);

        $sql      = "SELECT * FROM {$this->table()} {$where_sql} ORDER BY created_at DESC LIMIT %d OFFSET %d";
        $params[] = $limit;
        $params[] = $offset;
        $items    = $wpdb->get_results($wpdb->prepare($sql, $params), ARRAY_A);

        return [
            'items'     => $items ?: [],
            'total'     => $total,
            'page'      => (int) floor($offset / $limit) + 1,
            'max_pages' => (int) ceil(max(1, $total) / $limit),
        ];
    }

    /**
     * 获取收益统计
     */
    public function get_stats(int $user_id = 0): array {
        global $wpdb;

        $where = '';
        $params = [];
        if ($user_id > 0) {
            $where = 'WHERE user_id = %d';
            $params[] = $user_id;
        }

        $sql = "SELECT
                    COALESCE(SUM(amount), 0) as total,
                    COALESCE(SUM(CASE WHEN status = 'pending' THEN amount ELSE 0 END), 0) as pending,
                    COALESCE(SUM(CASE WHEN status = 'settled' THEN amount ELSE 0 END), 0) as settled,
                    COUNT(*) as count
                FROM {$this->table()} {$where}";

        if (!empty($params)) {
            $row = $wpdb->get_row($wpdb->prepare($sql, $params), ARRAY_A);
        } else {
            $row = $wpdb->get_row($sql, ARRAY_A);
        }

        return [
            'total'   => (float) ($row['total'] ?? 0),
            'pending' => (float) ($row['pending'] ?? 0),
            'settled' => (float) ($row['settled'] ?? 0),
            'count'   => (int) ($row['count'] ?? 0),
        ];
    }
}