/**
 * 授权服务
 * 提供账号授权检查功能
 */

const db = require('../middleware/dbProxy');
const dayjs = require('dayjs');

class AuthorizationService {
    /**
     * 检查账号授权状态
     * @param {string|number} identifier - 账号标识（sn_code 或 id）
     * @param {string} identifierType - 标识类型：'sn_code' 或 'id'
     * @returns {Promise<Object>} 授权检查结果 {is_authorized: boolean, remaining_days: number, message: string}
     */
    async checkAuthorization(identifier, identifierType = 'sn_code') {
        const pla_account = db.getModel('pla_account');

        const where = {};
        where[identifierType] = identifier;

        const account = await pla_account.findOne({ where });

        if (!account) {
            return {
                is_authorized: false,
                remaining_days: 0,
                message: '账号不存在'
            };
        }

        const accountData = account.toJSON();
        const authDate = accountData.authorization_date;
        const authDays = accountData.authorization_days || 0;

        // 如果没有授权信息，默认不允许
        if (!authDate || authDays <= 0) {
            return {
                is_authorized: false,
                remaining_days: 0,
                message: '账号未授权，请联系管理员'
            };
        }

        // 计算剩余天数
        const startDate = dayjs(authDate);
        const endDate = startDate.add(authDays, 'day');
        const now = dayjs();
        const remaining = endDate.diff(now, 'day', true);
        const remaining_days = Math.max(0, Math.ceil(remaining));

        if (remaining_days <= 0) {
            return {
                is_authorized: false,
                remaining_days: 0,
                message: '账号授权已过期，请联系管理员续费'
            };
        }

        return {
            is_authorized: true,
            remaining_days: remaining_days,
            message: `授权有效，剩余 ${remaining_days} 天`
        };
    }

    /**
     * 检查账号授权状态（快速检查，只返回是否授权）
     * @param {string|number} identifier - 账号标识（sn_code 或 id）
     * @param {string} identifierType - 标识类型：'sn_code' 或 'id'
     * @returns {Promise<boolean>} 是否授权
     */
    async isAuthorized(identifier, identifierType = 'sn_code') {
        const result = await this.checkAuthorization(identifier, identifierType);
        return result.is_authorized;
    }
}

module.exports = new AuthorizationService();