using System;
using System.Threading;
using System.Threading.Tasks;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
using Quartz;
using YhCore.Tasks.Jobs;

namespace YhCore.Tasks
{
    /// <summary>
    /// Quartz 调度宿主（对应 Java scheduler 包由 Spring 管理的调度器）。
    /// 承载框架内置 Job 模板；业务 Job 在 InitJobs 中追加注册。
    /// </summary>
    public class QuartzHostedService : IHostedService
    {
        private const string ServiceProviderKey = "services";

        private readonly ISchedulerFactory _schedulerFactory;
        private readonly IServiceProvider _serviceProvider;
        private IScheduler _scheduler;

        public QuartzHostedService(ISchedulerFactory schedulerFactory, IServiceProvider serviceProvider)
        {
            _schedulerFactory = schedulerFactory;
            _serviceProvider = serviceProvider;
        }

        public async Task StartAsync(CancellationToken cancellationToken)
        {
            _scheduler = await _schedulerFactory.GetScheduler(cancellationToken);
            _scheduler.Context.Put(ServiceProviderKey, _serviceProvider); // Job 经此取 DI 服务

            await InitJobs();

            await _scheduler.Start(cancellationToken);
        }

        public async Task StopAsync(CancellationToken cancellationToken)
        {
            if (_scheduler != null)
            {
                await _scheduler.Shutdown(waitForJobsToComplete: true, cancellationToken);
            }
        }

        private async Task InitJobs()
        {
            // ============ 定时任务注册 ============

            // 1. 审计日志清理（对应 Java SysOperationLogCleanupTask：每日凌晨 1:00 删除 30 天前 sys_operation_log 数据；
            //    设定时间窗口 0-2 点，取 1:00 居中）
            await ScheduleJobAsync<CleanupLogJob>("cleanup-log-job", "0 0 1 * * ?");

            // 2. 其他业务 Job 在此追加注册（示例：每 10 分钟执行一次）
            // await ScheduleJobAsync<TJob>("job-name", "0 */10 * * * ?");

            await Task.CompletedTask;
        }

        /// <summary>注册一个 Cron 定时任务</summary>
        protected async Task ScheduleJobAsync<TJob>(string jobName, string cronExpression) where TJob : IJob
        {
            var job = JobBuilder.Create<TJob>()
                .WithIdentity(jobName)
                .Build();

            var trigger = TriggerBuilder.Create()
                .WithIdentity(jobName + "-trigger")
                .WithCronSchedule(cronExpression)
                .Build();

            await _scheduler.ScheduleJob(job, trigger);
        }
    }
}