@page "/users"
@attribute [Authorize]
@using MudBlazor
@inject HttpClient Http
@inject ISnackbar Snackbar
@inject IDialogService DialogService

<PageTitle>QuantEngine - 사용자 관리</PageTitle>

<!-- Page Header -->
<div class="mb-6">
    <MudText Typo="Typo.h4" Class="mb-2">사용자 관리</MudText>
    <MudText Typo="Typo.body1" Class="text-muted">시스템 사용자 및 권한 관리</MudText>
</div>

<!-- Action Bar -->
<div class="d-flex justify-content-between align-items-center mb-4">
    <MudTextField @bind-Value="SearchQuery" Placeholder="사용자 검색..."
                  StartAdornment="@Icons.Material.Filled.Search"
                  Style="width: 300px;" />
    <MudButton Variant="Variant.Filled" Color="Color.Primary" OnClick="OpenAddUserDialog">
        <MudIcon Icon="@Icons.Material.Filled.Add" Class="mr-2" />
        새 사용자 추가
    </MudButton>
</div>

<!-- Users Table -->
<MudPaper Class="pa-4" Elevation="1">
    @if (_users.Count == 0)
    {
        <MudAlert Severity="Severity.Info">사용자가 없습니다.</MudAlert>
    }
    else
    {
        <MudTable Items="@FilteredUsers" Dense="true" Hover="true" Striped="true">
            <HeaderContent>
                <MudTh>이름</MudTh>
                <MudTh>역할</MudTh>
                <MudTh>상태</MudTh>
                <MudTh>생성일</MudTh>
                <MudTh>수정일</MudTh>
                <MudTh>작업</MudTh>
            </HeaderContent>
            <RowTemplate>
                <MudTd DataLabel="Name">
                    <div class="d-flex align-items-center gap-2">
                        <MudAvatar Size="Size.Small" Color="Color.Primary">@context.Username[0].ToString().ToUpper()</MudAvatar>
                        <MudText Typo="Typo.body2">@context.Username</MudText>
                    </div>
                </MudTd>
                <MudTd DataLabel="Role">
                    <MudChip T="string" Label="true" Size="Size.Small"
                             Color="@(context.Role == "Admin" ? Color.Primary : (context.Role == "Operator" ? Color.Secondary : Color.Default))"
                             Variant="Variant.Filled">
                        @context.Role
                    </MudChip>
                </MudTd>
                <MudTd DataLabel="Status">
                    <MudChip T="string" Label="true" Size="Size.Small"
                             Color="@(context.IsActive ? Color.Success : Color.Warning)"
                             Variant="Variant.Filled">
                        @(context.IsActive ? "활성" : "비활성")
                    </MudChip>
                </MudTd>
                <MudTd DataLabel="Joined">
                    <MudText Typo="Typo.body2">@FormatDate(context.CreatedAt)</MudText>
                </MudTd>
                <MudTd DataLabel="Updated">
                    <MudText Typo="Typo.body2">@FormatDate(context.UpdatedAt)</MudText>
                </MudTd>
                <MudTd DataLabel="Actions">
                    <MudButton Variant="Variant.Text" Size="Size.Small" Color="Color.Primary" OnClick="@(() => EditUser(context))">편집</MudButton>
                    <MudButton Variant="Variant.Text" Size="Size.Small" Color="Color.Error" OnClick="@(() => DeleteUser(context))">삭제</MudButton>
                </MudTd>
            </RowTemplate>
        </MudTable>
    }
</MudPaper>

<!-- Add/Edit Dialog -->
<MudDialog @bind-Visible="_dialogVisible" Options="_dialogOptions">
    <TitleContent>
        <MudText Typo="Typo.h6">
            <MudIcon Icon="@(_isEditMode ? Icons.Material.Filled.Edit : Icons.Material.Filled.Add)" Class="mr-3" />
            @(_isEditMode ? "사용자 편집" : "새 사용자 추가")
        </MudText>
    </TitleContent>
    <DialogContent>
        <MudForm Model="@_formModel" @ref="_form">
            <MudTextField T="string" @bind-Value="_formModel.Username" Label="사용자 ID" Required="true" Disabled="@_isEditMode"
                          RequiredError="사용자 ID를 입력해 주세요." Class="mb-3" />
            
            <MudTextField T="string" @bind-Value="_formModel.Password" Label="@(_isEditMode ? "새 비밀번호 (미입력시 유지)" : "비밀번호")" 
                          InputType="InputType.Password" Required="@(!_isEditMode)" RequiredError="비밀번호를 입력해 주세요." Class="mb-3" />
            
            <MudSelect T="string" @bind-Value="_formModel.Role" Label="역할 권한" Required="true" Class="mb-3">
                <MudSelectItem Value="@("Admin")">Admin (관리자)</MudSelectItem>
                <MudSelectItem Value="@("Operator")">Operator (운영자)</MudSelectItem>
                <MudSelectItem Value="@("Viewer")">Viewer (조회자)</MudSelectItem>
            </MudSelect>

            @if (_isEditMode)
            {
                <MudSwitch T="bool" @bind-Value="_formModel.IsActive" Color="Color.Success" Label="계정 활성화 상태" />
            }
        </MudForm>
    </DialogContent>
    <DialogActions>
        <MudButton Variant="Variant.Text" Color="Color.Default" OnClick="CloseDialog" Class="px-5">취소</MudButton>
        <MudButton Variant="Variant.Filled" Color="Color.Primary" OnClick="SaveUser" Class="px-5">저장</MudButton>
    </DialogActions>
</MudDialog>

@code {
    private List<UserDto> _users = new();
    private string SearchQuery = "";
    private bool _dialogVisible;
    private bool _isEditMode;
    private MudForm _form = new();
    private UserFormModel _formModel = new();
    private DialogOptions _dialogOptions = new() { MaxWidth = MaxWidth.Small, FullWidth = true, CloseButton = true };

    private IEnumerable<UserDto> FilteredUsers
    {
        get => string.IsNullOrEmpty(SearchQuery)
            ? _users
            : _users.Where(u => u.Username.Contains(SearchQuery, StringComparison.OrdinalIgnoreCase));
    }

    protected override async Task OnInitializedAsync()
    {
        await LoadUsers();
    }

    private async Task LoadUsers()
    {
        try
        {
            var res = await Http.GetFromJsonAsync<List<UserDto>>("api/users");
            if (res != null)
            {
                _users = res;
            }
        }
        catch (Exception ex)
        {
            Snackbar.Add($"사용자 목록 로드 실패: {ex.Message}", Severity.Error);
        }
    }

    private void OpenAddUserDialog()
    {
        _isEditMode = false;
        _formModel = new UserFormModel { Role = "Viewer", IsActive = true };
        _dialogVisible = true;
    }

    private void EditUser(UserDto user)
    {
        _isEditMode = true;
        _formModel = new UserFormModel
        {
            Username = user.Username,
            Role = user.Role,
            IsActive = user.IsActive,
            Password = "" // Clear password field for security
        };
        _dialogVisible = true;
    }

    private async Task DeleteUser(UserDto user)
    {
        bool? result = await DialogService.ShowMessageBox(
            "사용자 삭제", 
            $"정말로 사용자 '{user.Username}' 계정을 비활성화하시겠습니까?", 
            yesText: "비활성화", cancelText: "취소");

        if (result == true)
        {
            try
            {
                var response = await Http.DeleteAsync($"api/users?username={user.Username}");
                if (response.IsSuccessStatusCode)
                {
                    Snackbar.Add("사용자 계정이 비활성화되었습니다.", Severity.Success);
                    await LoadUsers();
                }
                else
                {
                    Snackbar.Add("계정 비활성화 작업에 실패했습니다.", Severity.Error);
                }
            }
            catch (Exception ex)
            {
                Snackbar.Add($"API 에러: {ex.Message}", Severity.Error);
            }
        }
    }

    private void CloseDialog()
    {
        _dialogVisible = false;
    }

    private async Task SaveUser()
    {
        await _form.Validate();
        if (!_form.IsValid) return;

        try
        {
            HttpResponseMessage response;
            if (_isEditMode)
            {
                response = await Http.PutAsJsonAsync("api/users", _formModel);
            }
            else
            {
                response = await Http.PostAsJsonAsync("api/users", _formModel);
            }

            if (response.IsSuccessStatusCode)
            {
                Snackbar.Add("사용자 정보가 성공적으로 저장되었습니다.", Severity.Success);
                _dialogVisible = false;
                await LoadUsers();
            }
            else
            {
                var error = await response.Content.ReadAsStringAsync();
                Snackbar.Add($"저장 실패: {error}", Severity.Error);
            }
        }
        catch (Exception ex)
        {
            Snackbar.Add($"API 오류 발생: {ex.Message}", Severity.Error);
        }
    }

    private string FormatDate(string isoString)
    {
        if (string.IsNullOrWhiteSpace(isoString)) return "-";
        if (DateTime.TryParse(isoString, out var dt))
        {
            return dt.ToLocalTime().ToString("yyyy-MM-dd HH:mm");
        }
        return isoString;
    }

    public class UserDto
    {
        public string Username { get; set; } = string.Empty;
        public string Role { get; set; } = string.Empty;
        public bool IsActive { get; set; }
        public string CreatedAt { get; set; } = string.Empty;
        public string UpdatedAt { get; set; } = string.Empty;
    }

    public class UserFormModel
    {
        public string Username { get; set; } = string.Empty;
        public string Password { get; set; } = string.Empty;
        public string Role { get; set; } = "Viewer";
        public bool IsActive { get; set; } = true;
    }
}