@page "/login"
@attribute [AllowAnonymous]
@inject NavigationManager Nav

<PageTitle>Anmelden – Timetracker</PageTitle>

<MudContainer MaxWidth="MaxWidth.Small" Class="mt-16">
    <MudStack AlignItems="AlignItems.Center" Spacing="4">

        @* ── Logo / Header ── *@
        <MudStack AlignItems="AlignItems.Center" Spacing="1">
            <MudIcon Icon="@Icons.Material.Filled.AccessTime"
                     Style="font-size:4rem; color:#1565C0" />
            <MudText Typo="Typo.h4" Style="font-weight:700; color:#1565C0">Timetracker</MudText>
        </MudStack>

        <MudPaper Elevation="4" Class="pa-6 rounded-xl" Style="width:100%">
            @* ── Static Tab Navigation ── *@
            <MudStack Row="true" Justify="Justify.Center" Class="mb-4">
                <MudButton Href="/login"
                           Variant="@(_activeTab == 0 ? Variant.Filled : Variant.Text)"
                           Color="Color.Primary"
                           Style="min-width: 120px; border-radius: 20px;">
                    Anmelden
                </MudButton>
                <MudButton Href="/login?tab=register"
                           Variant="@(_activeTab == 1 ? Variant.Filled : Variant.Text)"
                           Color="Color.Primary"
                           Style="min-width: 120px; border-radius: 20px;">
                    Registrieren
                </MudButton>
            </MudStack>

            <MudDivider Class="mb-6" />

            @if (_activeTab == 0)
            {
                @* ── Login Form ── *@
                <MudStack Spacing="3">
                    @if (_error != null)
                    {
                        <MudAlert Severity="Severity.Error" Dense="true">@_error</MudAlert>
                    }
                    <form action="/auth/login" method="post">
                        <MudStack Spacing="3">
                            <MudTextField T="string"
                                          Label="Benutzername"
                                          Variant="Variant.Outlined"
                                          Adornment="Adornment.Start"
                                          AdornmentIcon="@Icons.Material.Filled.Person"
                                          name="username"
                                          Required="true"
                                          AutoFocus="true" />
                            <MudTextField T="string"
                                          Label="Passwort"
                                          Variant="Variant.Outlined"
                                          Adornment="Adornment.Start"
                                          AdornmentIcon="@Icons.Material.Filled.Lock"
                                          InputType="InputType.Password"
                                          name="password"
                                          Required="true" />
                            <MudButton ButtonType="ButtonType.Submit"
                                       Variant="Variant.Filled"
                                       Color="Color.Primary"
                                       FullWidth="true"
                                       Size="Size.Large"
                                       StartIcon="@Icons.Material.Filled.Login"
                                       Class="mt-2">
                                Anmelden
                            </MudButton>
                        </MudStack>
                    </form>
                </MudStack>
            }
            else
            {
                @* ── Register Form ── *@
                <MudStack Spacing="3">
                    @if (_error != null)
                    {
                        <MudAlert Severity="Severity.Error" Dense="true">@_error</MudAlert>
                    }
                    <form action="/auth/register" method="post">
                        <MudStack Spacing="3">
                            <MudTextField T="string"
                                          Label="Benutzername"
                                          Variant="Variant.Outlined"
                                          Adornment="Adornment.Start"
                                          AdornmentIcon="@Icons.Material.Filled.Person"
                                          name="username"
                                          Required="true"
                                          HelperText="Mindestens 3 Zeichen" />
                            <MudTextField T="string"
                                          Label="Passwort"
                                          Variant="Variant.Outlined"
                                          Adornment="Adornment.Start"
                                          AdornmentIcon="@Icons.Material.Filled.Lock"
                                          InputType="InputType.Password"
                                          name="password"
                                          Required="true"
                                          HelperText="Mindestens 6 Zeichen" />
                            <MudButton ButtonType="ButtonType.Submit"
                                       Variant="Variant.Filled"
                                       Color="Color.Secondary"
                                       FullWidth="true"
                                       Size="Size.Large"
                                       StartIcon="@Icons.Material.Filled.PersonAdd"
                                       Class="mt-2">
                                Konto erstellen
                            </MudButton>
                        </MudStack>
                    </form>
                </MudStack>
            }
        </MudPaper>
    </MudStack>
</MudContainer>

@code {
    private int _activeTab = 0;
    private string? _error;

    [SupplyParameterFromQuery(Name = "error")]
    public string? ErrorParam { get; set; }

    [SupplyParameterFromQuery(Name = "tab")]
    public string? TabParam { get; set; }

    protected override void OnParametersSet()
    {
        _error = ErrorParam switch
        {
            "invalid" => "Benutzername oder Passwort falsch.",
            not null  => Uri.UnescapeDataString(ErrorParam),
            _         => null
        };
        _activeTab = TabParam == "register" ? 1 : 0;
    }
}