@using Sandbox;
@using Sandbox.UI;
@inherits Panel
@namespace Sandbox

<root>
    @if ( _selected.IsValid() )
    {
        <div class="header">
            <h2>
                <span>🎨</span>
                <span>@_selected.Title</span>
            </h2>
        </div>

        @if ( _properties.Count > 0 )
        {
            <ControlSheet Target="@_properties" />
        }
        else
        {
            <div class="empty-state">#spawnmenu.effects.no_properties</div>
        }
    }
    else
    {
        <div class="empty-state">#spawnmenu.effects.select_effect</div>
    }
</root>

@code
{
    PostProcessManager _manager;
    PostProcessResource _selected;
    List<SerializedProperty> _properties = new();

    public override void Tick()
    {
        if ( _manager is null )
            _manager = Game.ActiveScene.GetSystem<PostProcessManager>();

        var selectedPath = _manager?.SelectedPath;
        var resource = selectedPath != null
            ? ResourceLibrary.Get<PostProcessResource>( selectedPath )
            : null;

        if ( resource != _selected )
        {
            _selected = resource;
            RebuildProperties();
        }

        if ( _selected is not null )
            StateHasChanged();
    }

    void RebuildProperties()
    {
        var path = _selected?.ResourcePath;
        if ( path is null )
        {
            _properties = [];
            return;
        }

        var props = new List<SerializedProperty>();
        props.Add( TypeLibrary.CreateProperty( "Enabled",
            () => _manager?.IsEnabled( path ) ?? false,
            v => _manager?.Set( path, v ) ) );

        foreach ( var component in _manager?.GetSelectedComponents() ?? [] )
        {
            var so = TypeLibrary.GetSerializedObject( component );
            so.OnPropertyChanged = OnPropertyChanged;
            props.AddRange( so.Where( FilterProperties ) );
        }

        _properties = props;
    }

    static bool FilterProperties( SerializedProperty o )
    {
        if ( o.PropertyType is null ) return false;
        if ( o.PropertyType.IsAssignableTo( typeof(Delegate) ) ) return false;

        if ( o.IsMethod ) return true;
        if ( !o.HasAttribute<PropertyAttribute>() ) return false;

        return true;
    }

    void OnPropertyChanged( SerializedProperty prop )
    {
        foreach ( var target in prop.Parent.Targets )
        {
            if ( target is Component component )
                GameManager.ChangeProperty( component, prop.Name, prop.GetValue<object>() );
        }
    }

    protected override int BuildHash() => HashCode.Combine( _manager?.SelectedPath );
}