@page "/admin/users"
@rendermode InteractiveWebAssembly
@attribute [Authorize(Policy = "AdminOnly")]
@using System.Net.Http.Json
@using System.Security.Claims
@inject IAuthService AuthService
@inject ISnackbar Snackbar
@inject AuthenticationStateProvider AuthStateProvider
@inject IUserNotificationService UserNotificationService
@inject HttpClient Http
@inject IDialogService DialogService
@inject NavigationManager NavigationManager
@implements IDisposable

<PageTitle>Benutzerverwaltung – Timetracker</PageTitle>

@if (_loading)
{
    <MudStack AlignItems="AlignItems.Center" Class="mt-16" Spacing="3">
        <MudProgressCircular Color="Color.Primary" Indeterminate="true" Size="Size.Large" />
        <MudText Color="Color.Secondary">Lade Benutzer…</MudText>
    </MudStack>
}
else
{
    <MudStack Spacing="4">

        @* ── Header ── *@
        <MudPaper Elevation="4" Class="pa-5 rounded-xl"
                  Style="background: #991B1B; color:white;">
            <MudStack Row="true" AlignItems="AlignItems.Center" Spacing="3">
                <MudIcon Icon="@Icons.Material.Filled.AdminPanelSettings" Style="color:white; font-size:2rem" />
                <MudStack Spacing="0">
                    <MudText Typo="Typo.h5" Style="color:white; font-weight:700">Benutzerverwaltung</MudText>
                    <MudText Typo="Typo.caption" Style="color:rgba(255,255,255,0.72)">
                        @_users.Count Benutzer registriert
                    </MudText>
                </MudStack>
            </MudStack>
        </MudPaper>

        @* ── Tabelle ── *@
        <MudCard Elevation="3" Class="rounded-xl">
            <MudCardContent Class="pa-0">
                <MudTable Items="_users" Hover="true" Striped="true" Dense="false"
                          SortLabel="Sortieren">
                    <HeaderContent>
                        <MudTh><MudTableSortLabel SortBy="new Func<User, object>(u => u.Id)">ID</MudTableSortLabel></MudTh>
                        <MudTh><MudTableSortLabel SortBy="new Func<User, object>(u => u.Username)" InitialDirection="SortDirection.Ascending">Benutzername</MudTableSortLabel></MudTh>
                        <MudTh>Firma / Mandant</MudTh>
                        <MudTh Style="text-align:right">Aktionen</MudTh>
                    </HeaderContent>
                    <RowTemplate>
                        <MudTd>
                            <MudText Typo="Typo.body2" Color="Color.Secondary">@context.Id</MudText>
                        </MudTd>
                        <MudTd>
                            @if (_editUserId == context.Id)
                            {
                                <MudTextField @bind-Value="_editUsername"
                                              Variant="Variant.Outlined"
                                              Margin="Margin.Dense"
                                              Immediate="true"
                                              Style="max-width:220px"
                                              OnKeyDown="@(async e => { if (e.Key == "Enter") await SaveRename(context); })" />
                            }
                            else
                            {
                                <MudStack Row="true" AlignItems="AlignItems.Center" Spacing="2">
                                    <MudIcon Icon="@Icons.Material.Filled.AccountCircle"
                                             Color="@(context.Username == "marc" ? Color.Error : Color.Default)"
                                             Size="Size.Small" />
                                    <MudText Style="@(context.Username == "marc" ? "font-weight:700" : "")">
                                        @context.Username
                                    </MudText>
                                    @if (context.Username == "marc")
                                    {
                                        <MudChip T="string" Size="Size.Small" Color="Color.Error" Variant="Variant.Outlined">Admin</MudChip>
                                    }
                                </MudStack>
                            }
                        </MudTd>
                        <MudTd>
                            @if (_editUserId == context.Id)
                            {
                                <MudSelect @bind-Value="_editTenantId" Margin="Margin.Dense" T="int?" Label="Firma zuweisen" Variant="Variant.Outlined" Style="max-width:250px">
                                    <MudSelectItem T="int?" Value="@((int?)null)">Hauptdomain (System/Global)</MudSelectItem>
                                    @foreach (var tenant in _tenants)
                                    {
                                        <MudSelectItem T="int?" Value="@((int?)tenant.Id)">@tenant.Name (@tenant.Subdomain)</MudSelectItem>
                                    }
                                </MudSelect>
                            }
                            else
                            {
                                @if (context.TenantId.HasValue)
                                {
                                    var t = _tenants.FirstOrDefault(x => x.Id == context.TenantId.Value);
                                    <MudChip T="string" Color="Color.Primary" Variant="Variant.Outlined" Size="Size.Small">
                                        @(t?.Name ?? $"Firma #{context.TenantId}")
                                    </MudChip>
                                }
                                else
                                {
                                    <MudChip T="string" Color="Color.Default" Variant="Variant.Text" Size="Size.Small">
                                        @(context.Username == "marc" ? "SuperAdmin" : "Einzelnutzer")
                                    </MudChip>
                                }
                            }
                        </MudTd>
                        <MudTd Style="text-align:right">
                            @if (_editUserId == context.Id)
                            {
                                <MudIconButton Icon="@Icons.Material.Filled.Check"
                                               Color="Color.Success"
                                               Size="Size.Small"
                                               OnClick="@(() => SaveRename(context))" />
                                <MudIconButton Icon="@Icons.Material.Filled.Close"
                                               Color="Color.Default"
                                               Size="Size.Small"
                                               OnClick="CancelEdit" />
                            }
                            else
                            {
                                <MudIconButton Icon="@Icons.Material.Filled.Edit"
                                               Color="Color.Primary"
                                               Size="Size.Small"
                                               OnClick="@(() => StartEdit(context))" />
                                <MudTooltip Text="Passwort zurücksetzen">
                                    <MudIconButton Icon="@Icons.Material.Filled.LockReset"
                                                   Color="Color.Warning"
                                                   Size="Size.Small"
                                                   OnClick="@(() => OpenResetPasswordDialog(context))" />
                                </MudTooltip>
                                <MudTooltip Text="Stundenzettel (PDF) herunterladen">
                                    <MudIconButton Icon="@Icons.Material.Filled.PictureAsPdf"
                                                   Color="Color.Info"
                                                   Size="Size.Small"
                                                   OnClick="@(() => DownloadUserPdf(context))" />
                                </MudTooltip>
                                @if (context.Username != "marc")
                                {
                                    <MudIconButton Icon="@Icons.Material.Filled.DeleteOutline"
                                                   Color="Color.Error"
                                                   Size="Size.Small"
                                                   OnClick="@(() => DeleteUser(context))" />
                                }
                            }
                        </MudTd>
                    </RowTemplate>
                    <NoRecordsContent>
                        <MudText Color="Color.Secondary" Class="pa-4">Keine Benutzer gefunden.</MudText>
                    </NoRecordsContent>
                </MudTable>
            </MudCardContent>
        </MudCard>

    </MudStack>
}

@code {
    [PersistentState(AllowUpdates = true)]
    public List<User>? PersistentUsers { get; set; }

    [PersistentState(AllowUpdates = true)]
    public List<TenantStats>? PersistentTenants { get; set; }

    private List<User> _users = [];
    private List<TenantStats> _tenants = [];
    private bool _loading = true;
    private int? _editUserId;
    private string _editUsername = "";
    private int? _editTenantId;

    protected override async Task OnInitializedAsync()
    {
        if (PersistentUsers != null)
        {
            _users = PersistentUsers;
            _tenants = PersistentTenants ?? [];
            _loading = false;
        }

        var claim = (await AuthStateProvider.GetAuthenticationStateAsync())
            .User.FindFirst(ClaimTypes.NameIdentifier);
        if (claim == null) return;

        UserNotificationService.OnUsersChanged += RefreshUsers;
        
        if (PersistentUsers == null)
        {
            try
            {
                _users = await AuthService.GetAllUsersAsync();
                _tenants = await Http.GetFromJsonAsync<List<TenantStats>>("api/superadmin/tenants") ?? [];

                PersistentUsers = _users;
                PersistentTenants = _tenants;
                _loading = false;
            }
            catch (Exception ex)
            {
                Snackbar.Add($"Fehler beim Laden der Daten: {ex.Message}", Severity.Error);
            }
        }
    }

    private async Task RefreshUsers()
    {
        _users = await AuthService.GetAllUsersAsync();
        try
        {
            _tenants = await Http.GetFromJsonAsync<List<TenantStats>>("api/superadmin/tenants") ?? [];
        }
        catch
        {
            // Ignore background refresh errors
        }
        await InvokeAsync(StateHasChanged);
    }

    public void Dispose()
    {
        UserNotificationService.OnUsersChanged -= RefreshUsers;
    }

    private void StartEdit(User user)
    {
        _editUserId = user.Id;
        _editUsername = user.Username;
        _editTenantId = user.TenantId;
    }

    private void CancelEdit()
    {
        _editUserId = null;
        _editUsername = "";
        _editTenantId = null;
    }

    private async Task SaveRename(User user)
    {
        var trimmed = _editUsername.Trim();
        
        // 1. Rename if username changed
        if (trimmed != user.Username)
        {
            var error = await AuthService.RenameUserAsync(user.Id, trimmed);
            if (error != null)
            {
                Snackbar.Add(error, Severity.Error);
                return;
            }
            user.Username = trimmed;
        }

        // 2. Move to tenant if tenant ID changed
        if (_editTenantId != user.TenantId)
        {
            var error = await AuthService.AssignTenantAsync(user.Id, _editTenantId);
            if (error != null)
            {
                Snackbar.Add(error, Severity.Error);
                return;
            }
            user.TenantId = _editTenantId;
        }

        _editUserId = null;
        _editUsername = "";
        _editTenantId = null;
        
        Snackbar.Add("Benutzerdaten erfolgreich aktualisiert.", Severity.Success);
    }

    private async Task DeleteUser(User user)
    {
        await AuthService.DeleteUserAsync(user.Id);
        _users.Remove(user);
        Snackbar.Add($"Benutzer \"{user.Username}\" gelöscht.", Severity.Info);
    }

    private async Task OpenResetPasswordDialog(User user)
    {
        var parameters = new DialogParameters<ResetPasswordDialog>
        {
            { x => x.Username, user.Username }
        };

        var options = new DialogOptions { CloseButton = true, MaxWidth = MaxWidth.Small, FullWidth = true };
        var dialog = await DialogService.ShowAsync<ResetPasswordDialog>("Passwort zurücksetzen", parameters, options);
        var result = await dialog.Result;

        if (result != null && !result.Canceled && result.Data is string newPassword)
        {
            var error = await AuthService.ResetPasswordAsync(user.Id, newPassword);
            if (error != null)
            {
                Snackbar.Add(error, Severity.Error);
            }
            else
            {
                Snackbar.Add($"Passwort für {user.Username} wurde erfolgreich zurückgesetzt.", Severity.Success);
            }
        }
    }

    private async Task DownloadUserPdf(User user)
    {
        var options = new DialogOptions { CloseButton = true, MaxWidth = MaxWidth.ExtraSmall, FullWidth = true };
        var dialog = await DialogService.ShowAsync<MonthSelectorDialog>($"Stundenzettel für {user.Username}", options);
        var result = await dialog.Result;

        if (result != null && !result.Canceled && result.Data is MonthSelectorDialog.MonthSelectorResult data)
        {
            int year = data.Year;
            int month = data.Month;

            NavigationManager.NavigateTo($"api/tracker/export/month/pdf?userId={user.Id}&year={year}&month={month}", forceLoad: true);
        }
    }
}