using System.ComponentModel;
using System.Runtime.CompilerServices;
using System.Windows.Media;
using OrpaonVision.Core.Security;
using OrpaonVision.Core.Security.Contracts;
using OrpaonVision.Core.Security.Contracts.Commands;
using OrpaonVision.Core.Security.Contracts.Queries;

namespace OrpaonVision.ConfigApp.ViewModels;

/// <summary>
/// 用户管理ViewModel。
/// </summary>
public sealed class UserManagementViewModel : INotifyPropertyChanged
{
    private readonly IUserAppService _userAppService;

    private string _statusText = "准备就绪。";
    private Brush _statusBrush = Brushes.DarkGreen;
    private string _outputText = string.Empty;
    private UserDetailDto? _selectedUser;
    private string _searchKeyword = string.Empty;

    /// <summary>
    /// 构造函数。
    /// </summary>
    public UserManagementViewModel(IUserAppService userAppService)
    {
        _userAppService = userAppService;
    }

    /// <summary>
    /// 状态文本。
    /// </summary>
    public string StatusText
    {
        get => _statusText;
        private set => SetProperty(ref _statusText, value);
    }

    /// <summary>
    /// 状态画刷。
    /// </summary>
    public Brush StatusBrush
    {
        get => _statusBrush;
        private set => SetProperty(ref _statusBrush, value);
    }

    /// <summary>
    /// 输出文本。
    /// </summary>
    public string OutputText
    {
        get => _outputText;
        private set => SetProperty(ref _outputText, value);
    }

    /// <summary>
    /// 选中的用户。
    /// </summary>
    public UserDetailDto? SelectedUser
    {
        get => _selectedUser;
        private set => SetProperty(ref _selectedUser, value);
    }

    /// <summary>
    /// 搜索关键词。
    /// </summary>
    public string SearchKeyword
    {
        get => _searchKeyword;
        set => SetProperty(ref _searchKeyword, value);
    }

    /// <summary>
    /// 查询用户详情。
    /// </summary>
    public async Task QueryUserDetailAsync()
    {
        try
        {
            StatusBrush = Brushes.DarkGreen;
            StatusText = "正在查询用户详情...";

            if (string.IsNullOrWhiteSpace(SearchKeyword))
            {
                StatusBrush = Brushes.Orange;
                StatusText = "请输入用户ID或用户名";
                return;
            }

            // 这里演示如何查询用户详情
            // 实际实现需要根据SearchKeyword判断是用户ID还是用户名
            var userId = Guid.TryParse(SearchKeyword, out var parsedId) ? parsedId : Guid.NewGuid();
            var result = await _userAppService.GetDetailAsync(userId);

            if (result.Succeeded && result.Data != null)
            {
                SelectedUser = result.Data;
                StatusText = "用户详情查询成功";
                OutputText = $"用户名：{result.Data.UserName}\n" +
                             $"显示名称：{result.Data.DisplayName}\n" +
                             $"邮箱：{result.Data.Email}\n" +
                             $"状态：{result.Data.Status}\n" +
                             $"角色数：{result.Data.Roles.Count}\n" +
                             $"权限数：{result.Data.Permissions.Count}\n" +
                             $"最后登录：{result.Data.LastLoginAtUtc:yyyy-MM-dd HH:mm}";
            }
            else
            {
                StatusBrush = Brushes.OrangeRed;
                StatusText = "查询用户详情失败";
                OutputText = $"错误：{result.Message}";
                SelectedUser = null;
            }
        }
        catch (Exception ex)
        {
            StatusBrush = Brushes.OrangeRed;
            StatusText = "查询用户详情异常";
            OutputText = $"异常：{ex.Message}";
            SelectedUser = null;
        }
    }

    /// <summary>
    /// 创建新用户。
    /// </summary>
    public async Task CreateUserAsync()
    {
        try
        {
            StatusBrush = Brushes.DarkGreen;
            StatusText = "正在创建新用户...";

            // 这里演示如何创建用户
            var command = new OrpaonVision.Core.Security.Contracts.Commands.CreateUserCommand
            {
                UserName = "newuser_" + DateTime.Now.Ticks,
                DisplayName = "新用户",
                Email = "newuser@example.com",
                Password = "TempPassword123!",
                Roles = ["Operator"],
                Permissions = ["production.view", "training.view"],
                CreatedBy = "Admin"
            };

            var result = await _userAppService.CreateAsync(command);

            if (result.Succeeded)
            {
                StatusText = "用户创建成功";
                OutputText = $"用户ID：{result.Data}\n" +
                             $"用户名：{command.UserName}\n" +
                             $"显示名称：{command.DisplayName}\n" +
                             $"角色：{string.Join(", ", command.Roles)}\n" +
                             $"请及时修改初始密码";
            }
            else
            {
                StatusBrush = Brushes.OrangeRed;
                StatusText = "创建用户失败";
                OutputText = $"错误：{result.Message}";
            }
        }
        catch (Exception ex)
        {
            StatusBrush = Brushes.OrangeRed;
            StatusText = "创建用户异常";
            OutputText = $"异常：{ex.Message}";
        }
    }

    /// <summary>
    /// 更新用户信息。
    /// </summary>
    public async Task UpdateUserAsync()
    {
        try
        {
            StatusBrush = Brushes.DarkGreen;
            StatusText = "正在更新用户信息...";

            if (SelectedUser == null)
            {
                StatusBrush = Brushes.Orange;
                StatusText = "请先选择要更新的用户";
                return;
            }

            // 这里演示如何更新用户信息
            var command = new OrpaonVision.Core.Security.Contracts.Commands.UpdateUserCommand
            {
                UserId = SelectedUser.UserId,
                DisplayName = SelectedUser.DisplayName + " (已更新)",
                Email = SelectedUser.Email,
                IsActive = SelectedUser.IsActive,
                Roles = SelectedUser.Roles.ToList(),
                UpdatedBy = "Admin"
            };

            var result = await _userAppService.UpdateAsync(command);

            if (result.Succeeded)
            {
                StatusText = "用户信息更新成功";
                OutputText = $"用户ID：{command.UserId}\n" +
                             $"显示名称：{command.DisplayName}\n" +
                             $"状态：{(command.IsActive ? "激活" : "停用")}\n" +
                             $"角色：{string.Join(", ", command.Roles)}";
                
                // 重新查询用户详情以更新显示
                await QueryUserDetailAsync();
            }
            else
            {
                StatusBrush = Brushes.OrangeRed;
                StatusText = "更新用户信息失败";
                OutputText = $"错误：{result.Message}";
            }
        }
        catch (Exception ex)
        {
            StatusBrush = Brushes.OrangeRed;
            StatusText = "更新用户信息异常";
            OutputText = $"异常：{ex.Message}";
        }
    }

    /// <summary>
    /// 删除用户。
    /// </summary>
    public async Task DeleteUserAsync()
    {
        try
        {
            StatusBrush = Brushes.DarkGreen;
            StatusText = "正在删除用户...";

            if (SelectedUser == null)
            {
                StatusBrush = Brushes.Orange;
                StatusText = "请先选择要删除的用户";
                return;
            }

            // 这里演示如何删除用户
            var command = new OrpaonVision.Core.Security.Contracts.Commands.DeleteUserCommand
            {
                UserId = SelectedUser.UserId,
                DeletedBy = "Admin"
            };

            var result = await _userAppService.DeleteAsync(command);

            if (result.Succeeded)
            {
                StatusText = "用户删除成功";
                OutputText = $"已删除用户：{SelectedUser.UserName} ({SelectedUser.DisplayName})\n" +
                             $"用户ID：{command.UserId}\n" +
                             $"操作时间：{DateTime.UtcNow:yyyy-MM-dd HH:mm:ss}";
                
                SelectedUser = null;
                SearchKeyword = string.Empty;
            }
            else
            {
                StatusBrush = Brushes.OrangeRed;
                StatusText = "删除用户失败";
                OutputText = $"错误：{result.Message}";
            }
        }
        catch (Exception ex)
        {
            StatusBrush = Brushes.OrangeRed;
            StatusText = "删除用户异常";
            OutputText = $"异常：{ex.Message}";
        }
    }

    /// <summary>
    /// 重置用户密码。
    /// </summary>
    public async Task ResetUserPasswordAsync()
    {
        try
        {
            StatusBrush = Brushes.DarkGreen;
            StatusText = "正在重置用户密码...";

            if (SelectedUser == null)
            {
                StatusBrush = Brushes.Orange;
                StatusText = "请先选择要重置密码的用户";
                return;
            }

            // 这里演示如何重置用户密码
            var command = new OrpaonVision.Core.Security.Contracts.Commands.ResetUserPasswordCommand
            {
                UserId = SelectedUser.UserId,
                NewPassword = "NewTempPassword123!",
                ForceChangeOnNextLogin = true,
                ResetBy = "Admin"
            };

            var result = await _userAppService.ResetPasswordAsync(command);

            if (result.Succeeded)
            {
                StatusText = "密码重置成功";
                OutputText = $"用户：{SelectedUser.UserName}\n" +
                             $"新密码：{command.NewPassword}\n" +
                             $"下次登录必须修改：{(command.ForceChangeOnNextLogin ? "是" : "否")}\n" +
                             $"请及时通知用户";
            }
            else
            {
                StatusBrush = Brushes.OrangeRed;
                StatusText = "重置密码失败";
                OutputText = $"错误：{result.Message}";
            }
        }
        catch (Exception ex)
        {
            StatusBrush = Brushes.OrangeRed;
            StatusText = "重置密码异常";
            OutputText = $"异常：{ex.Message}";
        }
    }

    /// <summary>
    /// 分页查询用户列表。
    /// </summary>
    public async Task QueryUserListAsync()
    {
        try
        {
            StatusBrush = Brushes.DarkGreen;
            StatusText = "正在查询用户列表...";

            // 这里演示如何分页查询用户列表
            var query = new OrpaonVision.Core.Security.Contracts.Queries.UserQueryDto
            {
                Keyword = SearchKeyword,
                PageIndex = 1,
                PageSize = 20,
                SortField = "UserName",
                SortDirection = "ASC"
            };

            var result = await _userAppService.GetPagedListAsync(query);

            if (result.Succeeded && result.Data != null)
            {
                StatusText = "用户列表查询成功";
                OutputText = $"查询条件：{query.Keyword ?? "全部"}\n" +
                             $"用户总数：{result.Data.TotalCount}\n" +
                             $"当前页：{result.Data.PageIndex}/{result.Data.TotalPages}\n" +
                             $"本页记录：{result.Data.Items.Count}\n" +
                             $"查询时间：{DateTime.UtcNow:yyyy-MM-dd HH:mm:ss}";
            }
            else
            {
                StatusBrush = Brushes.OrangeRed;
                StatusText = "查询用户列表失败";
                OutputText = $"错误：{result.Message}";
            }
        }
        catch (Exception ex)
        {
            StatusBrush = Brushes.OrangeRed;
            StatusText = "查询用户列表异常";
            OutputText = $"异常：{ex.Message}";
        }
    }

    /// <inheritdoc />
    public event PropertyChangedEventHandler? PropertyChanged;

    private void SetProperty<T>(ref T field, T value, [CallerMemberName] string? propertyName = null)
    {
        if (EqualityComparer<T>.Default.Equals(field, value))
        {
            return;
        }

        field = value;
        PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
    }
}