vendor/a2ui/renderers/angular/src/lib/rendering/dynamic-component.ts

/*
 Copyright 2025 Google LLC

 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
 You may obtain a copy of the License at

      https://www.apache.org/licenses/LICENSE-2.0

 Unless required by applicable law or agreed to in writing, software
 distributed under the License is distributed on an "AS IS" BASIS,
 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 See the License for the specific language governing permissions and
 limitations under the License.
 */

import { Types, Primitives } from '@a2ui/lit/0.8';
import { Directive, inject, input } from '@angular/core';
import { MessageProcessor } from '../data';
import { Theme } from './theming';

let idCounter = 0;

@Directive({
  host: {
    '[style.--weight]': 'weight()',
  },
})
export abstract class DynamicComponent<T extends Types.AnyComponentNode = Types.AnyComponentNode> {
  protected readonly processor = inject(MessageProcessor);
  protected readonly theme = inject(Theme);

  readonly surfaceId = input.required<Types.SurfaceID | null>();
  readonly component = input.required<T>();
  readonly weight = input.required<string | number>();

  protected sendAction(action: Types.Action): Promise<Types.ServerToClientMessage[]> {
    const component = this.component();
    const surfaceId = this.surfaceId() ?? undefined;
    const context: Record<string, unknown> = {};

    if (action.context) {
      for (const item of action.context) {
        if (item.value.literalBoolean) {
          context[item.key] = item.value.literalBoolean;
        } else if (item.value.literalNumber) {
          context[item.key] = item.value.literalNumber;
        } else if (item.value.literalString) {
          context[item.key] = item.value.literalString;
        } else if (item.value.path) {
          const path = this.processor.resolvePath(item.value.path, component.dataContextPath);
          const value = this.processor.getData(component, path, surfaceId);
          context[item.key] = value;
        }
      }
    }

    const message: Types.A2UIClientEventMessage = {
      userAction: {
        name: action.name,
        sourceComponentId: component.id,
        surfaceId: surfaceId!,
        timestamp: new Date().toISOString(),
        context,
      },
    };

    return this.processor.dispatch(message);
  }

  protected resolvePrimitive(value: Primitives.StringValue | null): string | null;
  protected resolvePrimitive(value: Primitives.BooleanValue | null): boolean | null;
  protected resolvePrimitive(value: Primitives.NumberValue | null): number | null;
  protected resolvePrimitive(
    value: Primitives.StringValue | Primitives.BooleanValue | Primitives.NumberValue | null,
  ) {
    const component = this.component();
    const surfaceId = this.surfaceId();

    if (!value || typeof value !== 'object') {
      return null;
    } else if (value.literal != null) {
      return value.literal;
    } else if (value.path) {
      return this.processor.getData(component, value.path, surfaceId ?? undefined);
    } else if ('literalString' in value) {
      return value.literalString;
    } else if ('literalNumber' in value) {
      return value.literalNumber;
    } else if ('literalBoolean' in value) {
      return value.literalBoolean;
    }

    return null;
  }

  protected getUniqueId(prefix: string) {
    return `${prefix}-${idCounter++}`;
  }
}