using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
using Microsoft.EntityFrameworkCore;
using System;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
using Parking_space_WebAPI.Services;

public class ParkingLogCleanupService : BackgroundService
{
    private readonly IServiceScopeFactory _scopeFactory;

    public ParkingLogCleanupService(IServiceScopeFactory scopeFactory)
    {
        _scopeFactory = scopeFactory;
    }

    protected override async Task ExecuteAsync(CancellationToken stoppingToken)
    {
        while (!stoppingToken.IsCancellationRequested)
        {
            using (var scope = _scopeFactory.CreateScope())
            {
                var _context = scope.ServiceProvider.GetRequiredService<SqlContext>();

                try
                {
                    // 計算三個月前的日期
                    DateTime threeMonthsAgo = DateTime.Now.AddMonths(-3);

                    // 查找三個月前的資料
                    var oldLogs = await _context.ParkingLogs
                        .Where(log => log.Timestamp < threeMonthsAgo)
                        .ToListAsync();

                    if (oldLogs.Any())
                    {
                        _context.ParkingLogs.RemoveRange(oldLogs);
                        await _context.SaveChangesAsync();
                        Console.WriteLine($"{oldLogs.Count} old parking logs deleted.");
                    }
                }
                catch (Exception ex)
                {
                    // 錯誤顯示
                    Console.WriteLine($"An error occurred during cleanup: {ex.Message}");
                }
            }

            // 每 24 小時執行一次清理
            await Task.Delay(TimeSpan.FromDays(1), stoppingToken);
        }
    }
}