@namespace DeepDrftPublic.Client.Controls
@using DeepDrftPublic.Client.Services
@implements IDisposable
@inject WaveformVisualizerControlState State

@* Theater-Mode toggle (Phase 20 §3). The single affordance placed identically on all three release
   detail pages — immediately to the LEFT of the lava-lamp WaveformVisualizerControlPopover trigger.
   It is purely a mutation surface: tapping it flips State.TheaterMode and raises Changed; the detail
   pages observe that to gate their content @if, and the player bar observes it to grow. This component
   reaches into no page and no bar — single source, multiple observers (§6).

   Visible only when the lava OR waveform subsystem is on — there is nothing to go to theater FOR if both
   are off (§3.2) — AND when <see cref="Available"/> is true. The page supplies Available so the toggle
   only appears when this page's release is the one playing (Phase 20 Wave 2 §3): the toggle owns the
   subsystem gate; the page owns the release-playing predicate. Disabled until interactive (§3.4), the
   same prerender guard the lava/Play buttons use. Active visual state when Theater is ON. .dd-accent-icon
   gives the green-accent glyph in both themes with zero new CSS (§8) — same as the lava-lamp trigger. *@

@if (Available && (State.LavaEnabled || State.WaveformEnabled))
{
    <div class="dd-accent-icon">
        <MudTooltip Text="@(State.TheaterMode ? "Exit theater mode" : "Theater mode")">
            <MudIconButton Icon="@Icons.Material.Filled.Theaters"
                           Size="@IconSize"
                           Color="Color.Secondary"
                           Disabled="@(!RendererInfo.IsInteractive)"
                           OnClick="@Toggle"
                           aria-label="Theater mode"
                           aria-pressed="@State.TheaterMode" />
        </MudTooltip>
    </div>
}

@code {
    /// <summary>Trigger-icon size. Defaults Large to match the lava-lamp popover trigger it sits beside.</summary>
    [Parameter] public Size IconSize { get; set; } = Size.Large;

    /// <summary>
    /// Whether the toggle is available on this surface (Phase 20 Wave 2 §3). The page passes the
    /// "this release is the one playing" predicate here; Theater Mode only applies to the playing
    /// release, so a detail page whose release is not playing passes <c>false</c> and shows no toggle.
    /// Defaults <c>true</c> so surfaces with no release-scoping (none today) keep the subsystem-only gate.
    /// </summary>
    [Parameter] public bool Available { get; set; } = true;

    protected override void OnInitialized() => State.Changed += OnStateChanged;

    // The toggle's own visibility and active state both key off State, which another observer (or this
    // button) may mutate, so re-render on every Changed — same idempotent posture the visualizer bridge uses.
    private void OnStateChanged() => InvokeAsync(StateHasChanged);

    private void Toggle()
    {
        State.TheaterMode = !State.TheaterMode;
        State.NotifyChanged();
    }

    public void Dispose() => State.Changed -= OnStateChanged;
}