using System;
using PhxhSDK;
using Framework;
using Gameplay;
using UnityEngine;
using Gameplay.Common;

public class CrossDayChecker : Singlenton<CrossDayChecker>, IUpdatable, IInitable
{
    public bool DeleteSaveData;

    // 检查时间点
    private TimeSpan checkPointTime;

    // 记录上次检查的时间
    private DateTime lastCheckTime;
    
    // 服务器时间与本地时间的差值（毫秒）
    private long serverTimeOffset;
    
    private bool _init;
    public bool disableCheck = false;

    public void SetCheckTime(TimeSpan checkTime)
    {
        checkPointTime = checkTime;
    }

    public void Update(float deltaTime)
    {
        if (!_init) return;
        if (disableCheck) return;
        
        // 使用本地时间加上差值计算服务器时间，避免频繁网络请求
        var now = GetEstimatedServerTime();

        // 检测跨天
        if (HasCrossedDay(lastCheckTime, now))
        {
            DebugUtil.Log("跨天了！");
            EventManager.Instance.Send(EventManager.EventName.CrossDay);
        }

        // 检测跨周
        if (HasCrossedWeek(lastCheckTime, now))
        {
            DebugUtil.Log("跨周了！");
            EventManager.Instance.Send(EventManager.EventName.CrossWeek);
        }

        // 检测跨月
        if (HasCrossedMonth(lastCheckTime, now))
        {
            DebugUtil.Log("跨月了！");
            EventManager.Instance.Send(EventManager.EventName.CrossMonth);
        }

        lastCheckTime = now;
    }

    public void InitForLoginOk()
    {
        // 从配置中获取跨天时间点
        checkPointTime = new TimeSpan(GLConfig.Inst.data.DailyChangeHour, 0, 0);
        
        // 初始化时计算服务器时间与本地时间的差值
        DateTime serverTime = CommonUtils.GetCurTime(CommonUtils.E_TimeType.Server);
        DateTime localTime = DateTime.Now;
        serverTimeOffset = (long)(serverTime - localTime).TotalMilliseconds;
        DebugUtil.Log($"CrossDayChecker: 服务器时间偏移量：{serverTimeOffset}毫秒");
        
        if (PlayerPrefs.HasKey("CrossDayChecker_LastCheckTime"))
        {
            string savedTime = PlayerPrefs.GetString("CrossDayChecker_LastCheckTime");
            if (DateTime.TryParse(savedTime, out var parsedTime))
            {
                lastCheckTime = parsedTime;
                DebugUtil.Log($"CrossDayChecker: 成功加载上次检查时间：{lastCheckTime}");
            }
            else
            {
                DebugUtil.Log("CrossDayChecker: 无法解析存储的时间，使用当前服务器时间作为初始化时间。");
                lastCheckTime = serverTime;
                SendAllCrossEvent();
            }
        }
        else
        {
            DebugUtil.Log("CrossDayChecker: 本地存储中未找到上次检查时间，使用当前服务器时间作为初始化时间。");
            lastCheckTime = serverTime;
            SendAllCrossEvent();
        }

        _init = true;
    }
    
    /// <summary>
    /// 根据本地时间和时间偏移量估算服务器时间
    /// </summary>
    private DateTime GetEstimatedServerTime()
    {
        return DateTime.Now.AddMilliseconds(serverTimeOffset);
    }

    /// <summary>
    /// 检测是否跨天
    /// </summary>
    private bool HasCrossedDay(DateTime previousTime, DateTime currentTime)
    {
        var currentCrossTime = GetCrossTime(currentTime);
        return currentTime >= currentCrossTime && previousTime < currentCrossTime;
    }

    /// <summary>
    /// 检测是否跨周
    /// </summary>
    private bool HasCrossedWeek(DateTime previousTime, DateTime currentTime)
    {
        var previousCrossTime = GetCrossTime(previousTime).StartOfWeek();
        var currentCrossTime = GetCrossTime(currentTime).StartOfWeek();

        return currentCrossTime > previousCrossTime && currentTime >= currentCrossTime;
    }

    /// <summary>
    /// 检测是否跨月
    /// </summary>
    private bool HasCrossedMonth(DateTime previousTime, DateTime currentTime)
    {
        var previousCrossTime = GetCrossTime(previousTime).StartOfMonth();
        var currentCrossTime = GetCrossTime(currentTime).StartOfMonth();

        return currentCrossTime > previousCrossTime && currentTime >= currentCrossTime;
    }

    /// <summary>
    /// 获取指定时间的检查点时间
    /// </summary>
    private DateTime GetCrossTime(DateTime date)
    {
        // 验证 date 是否在有效范围内
        if (date < DateTime.MinValue || date > DateTime.MaxValue)
        {
            throw new ArgumentOutOfRangeException(nameof(date), "Input date is out of valid range.");
        }

        var crossTime = date.Date + checkPointTime;

        if (date.TimeOfDay < checkPointTime)
        {
            if (crossTime > DateTime.MinValue.AddDays(1))
            {
                crossTime = crossTime.AddDays(-1);
            }
            else
            {
                crossTime = DateTime.MinValue;
            }
        }

        return crossTime;
    }

    private void SendAllCrossEvent()
    {
        EventManager.Instance.Send(EventManager.EventName.CrossDay);
        EventManager.Instance.Send(EventManager.EventName.CrossWeek);
        EventManager.Instance.Send(EventManager.EventName.CrossMonth);
    }

    public void Init()
    {
    }

    public void Release()
    {
        if (DeleteSaveData) return;
        PlayerPrefs.SetString("CrossDayChecker_LastCheckTime", lastCheckTime.ToString("o"));
        PlayerPrefs.Save();
        DebugUtil.Log($"CrossDayChecker: 保存最后检查时间：{lastCheckTime}");
    }
}

/// <summary>
/// DateTime 的扩展方法
/// </summary>
public static class DateTimeExtensions
{
    /// <summary>
    /// 获取指定日期所在周的起始时间（以跨天时间点为准）
    /// </summary>
    public static DateTime StartOfWeek(this DateTime date)
    {
        // 周一为一周的起始
        var diff = (int)date.DayOfWeek - (int)DayOfWeek.Monday;
        if (diff < 0)
        {
            diff += 7;
        }

        return date.AddDays(-diff).Date;
    }

    /// <summary>
    /// 获取指定日期所在月的起始时间（以跨天时间点为准）
    /// </summary>
    public static DateTime StartOfMonth(this DateTime date)
    {
        return new DateTime(date.Year, date.Month, 1);
    }
}