deepdrft/DeepDrftPublic.Client/Layout/DeepDrftMenu.razor

@using DeepDrftPublic.Client.Common
@using DeepDrftPublic.Client.Services

@* Desktop Menu *@
<div class="d-none d-sm-flex">
    <nav class="@NavClass">
        <a class="dd-nav-brand" href="/">Deep DRFT</a>

        <ul class="dd-nav-links">
            @foreach (var navPage in Pages.MenuPages)
            {
                <li>
                    <a href="@navPage.Route" class="dd-nav-link">@navPage.Name</a>
                </li>
            }
        </ul>

        <div class="dd-nav-actions">
            <button type="button"
                    class="dd-nav-cta"
                    disabled="@_streamLoading"
                    aria-busy="@_streamLoading.ToString().ToLowerInvariant()"
                    @onclick="StreamNow">
                @if (_streamLoading)
                {
                    <span>Finding a track&#8230;</span>
                }
                else
                {
                    <span>Stream Now &#9654;</span>
                }
            </button>
            @* <button type="button" *@
            @*         class="dd-nav-toggle" *@
            @*         aria-label="Toggle dark mode" *@
            @*         aria-pressed="@IsDarkMode.ToString().ToLowerInvariant()" *@
            @*         @onclick="DarkModeToggle"> *@
            @*     @((MarkupString)DarkLightModeIconSvg) *@
            @* </button> *@
        </div>

        @if (_streamMessage is not null)
        {
            <p class="dd-nav-stream-message" role="status">@_streamMessage</p>
        }
    </nav>
</div>

@* Mobile Menu *@
<div class="d-flex d-sm-none">
    <nav class="@NavClass">
        <a class="dd-nav-brand" href="/">Deep DRFT</a>
        
        <div class="dd-nav-actions">
            @* <button type="button" *@
            @*         class="dd-nav-toggle" *@
            @*         aria-label="Toggle dark mode" *@
            @*         aria-pressed="@IsDarkMode.ToString().ToLowerInvariant()" *@
            @*         @onclick="DarkModeToggle"> *@
            @*     @((MarkupString)DarkLightModeIconSvg) *@
            @* </button> *@
            <button type="button"
                    class="dd-nav-hamburger"
                    aria-label="Toggle navigation"
                    aria-expanded="@_mobileMenuOpen.ToString().ToLowerInvariant()"
                    @onclick="ToggleMobileMenu">
                <span></span><span></span><span></span>
            </button>
        </div>

        @if (_mobileMenuOpen)
        {
            <ul class="dd-nav-links dd-nav-links-mobile">
                @foreach (var navPage in Pages.MenuPages)
                {
                    <li>
                        <a href="@navPage.Route" class="dd-nav-link" @onclick="CloseMobileMenu">@navPage.Name</a>
                    </li>
                }
                <li>
                    <button type="button"
                            class="dd-nav-cta"
                            disabled="@_streamLoading"
                            aria-busy="@_streamLoading.ToString().ToLowerInvariant()"
                            @onclick="StreamNowMobile">
                        @if (_streamLoading)
                        {
                            <span>Finding a track&#8230;</span>
                        }
                        else
                        {
                            <span>Stream Now &#9654;</span>
                        }
                    </button>
                </li>
            </ul>
        }

        @if (_streamMessage is not null)
        {
            <p class="dd-nav-stream-message" role="status">@_streamMessage</p>
        }
    </nav>
</div>

@implements IDisposable

@code {
    [Inject] public required DarkModeCookieService DarkModeCookieService { get; set; }
    [Inject] public required ITrackDataService TrackData { get; set; }
    [CascadingParameter] public IStreamingPlayerService? PlayerService { get; set; }

    // Elevation is vestigial under the frosted-glass design but kept on the parameter
    // surface so MainLayout's <DeepDrftMenu Elevation="..."> call site stays intact.
    [Parameter] public int Elevation { get; set; }
    [Parameter] public required bool IsDarkMode { get; set; }
    [Parameter] public required EventCallback<bool> IsDarkModeChanged { get; set; }
    
    private bool _mobileMenuOpen;
    private bool _streamLoading;
    private string? _streamMessage;
    private CancellationTokenSource? _messageCts;

    private const string EmptyLibraryMessage = "No tracks yet — check back soon.";
    private const string FetchFailedMessage = "Couldn't reach the library — try again.";

    private Task StreamNow() => StreamNowCore(closeMobileMenu: false);

    private Task StreamNowMobile() => StreamNowCore(closeMobileMenu: true);

    private async Task StreamNowCore(bool closeMobileMenu)
    {
        // Re-entrancy guard: the button is disabled while loading, but guard in code too so a
        // double-dispatch can never start two concurrent streams.
        if (_streamLoading) return;

        _streamLoading = true;
        _streamMessage = null;

        // Warm the AudioContext FIRST, inside the gesture's call stack and before the network
        // await below. Safari only lets a suspended AudioContext resume while the originating
        // user gesture is still active; awaiting GetRandomTrack() first would consume the gesture
        // and leave playback silently refused. PlayerService is null only outside the
        // AudioPlayerProvider cascade (it should always be present in the public layout).
        var warmTask = PlayerService?.WarmAudioContext() ?? Task.CompletedTask;

        try
        {
            await warmTask;
            var result = await TrackData.GetRandomTrack();

            if (!result.Success)
            {
                ShowTransientMessage(FetchFailedMessage);
                return;
            }

            if (result.Value is not { } track)
            {
                ShowTransientMessage(EmptyLibraryMessage);
                return;
            }

            if (closeMobileMenu)
                _mobileMenuOpen = false;

            // Track is found — clear the loading state immediately so the button
            // reverts to "Stream Now ▶" before the stream begins.
            _streamLoading = false;
            StateHasChanged();

            if (PlayerService is not null)
                await PlayerService.SelectTrackStreaming(track);
        }
        catch (Exception)
        {
            ShowTransientMessage(FetchFailedMessage);
        }
        finally
        {
            _streamLoading = false;
        }
    }

    private void ShowTransientMessage(string message)
    {
        _streamMessage = message;

        // Cancel any in-flight clear timer so the newest message gets its full display window.
        _messageCts?.Cancel();
        _messageCts?.Dispose();
        _messageCts = new CancellationTokenSource();
        var token = _messageCts.Token;

        _ = ClearMessageAfterDelayAsync(token);
    }

    private async Task ClearMessageAfterDelayAsync(CancellationToken token)
    {
        try
        {
            await Task.Delay(TimeSpan.FromSeconds(4), token);
        }
        catch (TaskCanceledException)
        {
            return;
        }

        _streamMessage = null;
        await InvokeAsync(StateHasChanged);
    }

    public void Dispose()
    {
        _messageCts?.Cancel();
        _messageCts?.Dispose();
    }

    protected override async Task OnAfterRenderAsync(bool firstRender)
    {
        if (firstRender)
        {
            // Runs here (not OnInitializedAsync) because OnAfterRenderAsync(firstRender)
            // is guaranteed not to execute during any SSR prerender pass. During prerender
            // (now interactive across all of Routes), awaiting IsDarkModeChanged.InvokeAsync
            // triggers a parent re-render cycle that cannot complete on the prerender renderer
            // and hangs the response. Server-side DarkModeService has already seeded
            // DarkModeSettings via PersistentComponentState, so the prerender paint is
            // already correct; this call reads that persisted value and propagates it to the
            // parent so the menu's IsDarkMode parameter stays consistent with DarkModeSettings.
            IsDarkMode = DarkModeCookieService.GetDarkMode();
            await IsDarkModeChanged.InvokeAsync(IsDarkMode);
        }
    }

    private string NavClass => IsDarkMode ? "dd-nav dd-nav-dark" : "dd-nav dd-nav-light";

    private string DarkLightModeIconSvg => IsDarkMode ? DDIcons.GasLampLit : DDIcons.GasLamp;

    private async Task DarkModeToggle()
    {
        IsDarkMode = !IsDarkMode;
        await DarkModeCookieService.SetDarkModeAsync(IsDarkMode);
        await IsDarkModeChanged.InvokeAsync(IsDarkMode);
    }

    private void ToggleMobileMenu() => _mobileMenuOpen = !_mobileMenuOpen;

    private void CloseMobileMenu() => _mobileMenuOpen = false;
}