// Copyright (c) Microsoft Corporation.
// Licensed under the MIT License.

#include "DocString.h"
import "CompositionSwitcher.idl";
import "IReactContext.idl";
import "IReactPropertyBag.idl";
import "ReactInstanceSettings.idl";

namespace Microsoft.ReactNative.Composition
{
  [experimental]
  [webhosthidden]
  enum ResourceType {
    DOC_STRING("Resource type for a @Windows.UI.Color")
    Color
  };

  [webhosthidden]
  [experimental]
  runtimeclass CustomResourceResult {
    Object Resource;
    DOC_STRING("The value of this resource should resolve to the value of another ResourceId")
    String AlternateResourceId;
  };

  [webhosthidden]
  [experimental]
  DOC_STRING("Applications can implement this interface to provide custom values for native platform colors.")
  interface ICustomResourceLoader {
    DOC_STRING("Called when a theme is queried for a specific resource. "
    "resourceId will be the name of the platform color. "
    "Implementations should return an empty result if the resource is not being overridden.")
    void GetResource(String resourceId, ResourceType resourceType, CustomResourceResult result);

    DOC_STRING("Implementations should raise this event if the platform colors will return new values")
    event Windows.Foundation.EventHandler<Object> ResourcesChanged;
  };

  namespace Experimental {
    [webhosthidden]
    [experimental]
    interface IInternalTheme {
      Microsoft.ReactNative.Composition.Experimental.IBrush InternalPlatformBrush(String platformColor);
    }
  }

  [webhosthidden]
  [experimental]
  runtimeclass Theme {
    Theme(Microsoft.ReactNative.IReactContext reactContext, ICustomResourceLoader resourceLoader);

    Microsoft.UI.Composition.CompositionBrush PlatformBrush(String platformColor);

    Boolean TryGetPlatformColor(String platformColor, out Windows.UI.Color color);
    DOC_STRING("An empty theme is used when the final theme is not yet known.  It will generally return transparent colors.")
    Boolean IsEmpty { get; };

    event Windows.Foundation.EventHandler<Object> ThemeChanged;

    static Theme GetDefaultTheme(Microsoft.ReactNative.IReactContext context);
    static void SetDefaultResources(Microsoft.ReactNative.ReactInstanceSettings settings, ICustomResourceLoader theme);
  };

} // namespace Microsoft.ReactNative