using Admin.NET.Core.Service;
using Microsoft.AspNetCore.SignalR;

namespace Admin.NET.Plugin.ApprovalFlow.Service;

/// <summary>
/// 流程通知服务 — 按 JSON 配置分渠道调度
/// </summary>
public class FlowNotifyService : ITransient
{
    private readonly IHubContext<OnlineUserHub, IOnlineUserHub> _hubContext;
    private readonly SysCacheService _cacheService;

    public FlowNotifyService(
        IHubContext<OnlineUserHub, IOnlineUserHub> hubContext,
        SysCacheService cacheService)
    {
        _hubContext = hubContext;
        _cacheService = cacheService;
    }

    public async Task NotifyUsers(List<long> userIds, FlowNotification notification)
    {
        if (userIds.Count == 0) return;

        var cfg = App.GetConfig<NotifyChannelConfig>("ApprovalFlow:Notify");

        if (cfg?.SignalR != false)
            await SendSignalR(userIds, notification);

        if (cfg?.DingTalk == true)
            await SendDingTalk(userIds, notification);

        if (cfg?.WorkWeixin == true)
            await SendWorkWeixin(userIds, notification);

        if (cfg?.Email == true)
            await SendEmail(userIds, notification);

        if (cfg?.Sms == true)
            await SendSms(userIds, notification);
    }

    public async Task NotifyUrge(List<long> userIds, long instanceId, string title)
    {
        await NotifyUsers(userIds, new FlowNotification
        {
            Type = FlowNotificationTypeEnum.Urge,
            InstanceId = instanceId,
            Title = $"【催办】{title}",
            Content = "流程发起人催促您尽快审批，请及时处理。",
        });
    }

    public async Task NotifyNewTask(List<long> userIds, long instanceId, string title, string? nodeName)
    {
        await NotifyUsers(userIds, new FlowNotification
        {
            Type = FlowNotificationTypeEnum.NewTask,
            InstanceId = instanceId,
            Title = $"【待审批】{title}",
            Content = $"您有一条新的审批任务（{nodeName}），请及时处理。",
        });
    }

    public async Task NotifyFlowCompleted(long initiatorId, long instanceId, string title, FlowInstanceStatusEnum finalStatus)
    {
        var statusText = finalStatus == FlowInstanceStatusEnum.Approved ? "已通过" : "已拒绝";
        await NotifyUsers(new List<long> { initiatorId }, new FlowNotification
        {
            Type = FlowNotificationTypeEnum.FlowCompleted,
            InstanceId = instanceId,
            Title = $"【审批{statusText}】{title}",
            Content = $"您发起的审批流程已{statusText}。",
        });
    }

    /// <summary>
    /// 转办通知 — 通知被转办人
    /// </summary>
    public async Task NotifyTransferred(long targetUserId, long instanceId, string title, string? fromName)
    {
        await NotifyUsers(new List<long> { targetUserId }, new FlowNotification
        {
            Type = FlowNotificationTypeEnum.Transferred,
            InstanceId = instanceId,
            Title = $"【转办】{title}",
            Content = $"{fromName} 将一条审批任务转交给您，请及时处理。",
        });
    }

    /// <summary>
    /// 退回通知 — 通知被退回节点的审批人
    /// </summary>
    public async Task NotifyReturned(List<long> userIds, long instanceId, string title, string? returnedBy)
    {
        await NotifyUsers(userIds, new FlowNotification
        {
            Type = FlowNotificationTypeEnum.Returned,
            InstanceId = instanceId,
            Title = $"【退回】{title}",
            Content = $"{returnedBy} 已退回该审批，请重新审核。",
        });
    }

    /// <summary>
    /// 加签通知 — 通知被加签人
    /// </summary>
    public async Task NotifyAddSign(long targetUserId, long instanceId, string title, string? fromName)
    {
        await NotifyUsers(new List<long> { targetUserId }, new FlowNotification
        {
            Type = FlowNotificationTypeEnum.AddSign,
            InstanceId = instanceId,
            Title = $"【加签】{title}",
            Content = $"{fromName} 邀请您参与审批，请及时处理。",
        });
    }

    /// <summary>
    /// 撤回通知 — 通知被取消的审批人
    /// </summary>
    public async Task NotifyWithdrawn(List<long> userIds, long instanceId, string title, string? initiatorName)
    {
        await NotifyUsers(userIds, new FlowNotification
        {
            Type = FlowNotificationTypeEnum.Withdrawn,
            InstanceId = instanceId,
            Title = $"【已撤回】{title}",
            Content = $"{initiatorName} 已撤回该审批流程。",
        });
    }

    // ═══════════════════════════════════════════
    //  各渠道发送实现
    // ═══════════════════════════════════════════

    private async Task SendSignalR(List<long> userIds, FlowNotification notification)
    {
        var onlineUsers = _cacheService.HashGetAll<SysOnlineUser>(CacheConst.KeyUserOnline);
        var connectionIds = onlineUsers
            .Where(u => userIds.Contains(u.Value.UserId))
            .Select(u => u.Value.ConnectionId)
            .ToList();

        if (connectionIds.Count == 0) return;

        await _hubContext.Clients.Clients(connectionIds).ReceiveMessage(new
        {
            title = notification.Title,
            message = notification.Content,
            type = notification.Type.ToString(),
            instanceId = notification.InstanceId,
        });
    }

    private Task SendDingTalk(List<long> userIds, FlowNotification notification)
    {
        // TODO: 接入 DingTalk 开放平台 API
        return Task.CompletedTask;
    }

    private Task SendWorkWeixin(List<long> userIds, FlowNotification notification)
    {
        // TODO: 接入企业微信消息推送 API
        return Task.CompletedTask;
    }

    private Task SendEmail(List<long> userIds, FlowNotification notification)
    {
        // TODO: 接入 SMTP / 邮件服务
        return Task.CompletedTask;
    }

    private Task SendSms(List<long> userIds, FlowNotification notification)
    {
        // TODO: 接入短信服务
        return Task.CompletedTask;
    }
}

public class FlowNotification
{
    public FlowNotificationTypeEnum Type { get; set; }
    public long InstanceId { get; set; }
    public string Title { get; set; } = "";
    public string Content { get; set; } = "";
}

/// <summary>
/// 通知类型
/// </summary>
public enum FlowNotificationTypeEnum
{
    NewTask,
    Urge,
    FlowCompleted,
    Transferred,
    Returned,
    AddSign,
    Withdrawn,
}

/// <summary>
/// 通知渠道配置（来自 ApprovalFlow:Notify JSON）
/// </summary>
public class NotifyChannelConfig
{
    public bool SignalR { get; set; } = true;
    public bool DingTalk { get; set; }
    public bool WorkWeixin { get; set; }
    public bool Email { get; set; }
    public bool Sms { get; set; }
}