import { debugLog } from "#src/debug";
import type { SubagentManagerObserver } from "#src/lifecycle/subagent-manager";
import type { CompactionInfo, Subagent } from "#src/types";

/**
 * Fans out SubagentManager lifecycle notifications to multiple observers.
 *
 * Lets the manager keep its single-observer contract while several independent
 * consumers (event/notification dispatch, the reactive widget) subscribe.
 * Each delegate is isolated: a throw in one does not suppress the others.
 */
export class CompositeSubagentObserver implements SubagentManagerObserver {
  private readonly delegates: SubagentManagerObserver[];

  constructor(delegates: SubagentManagerObserver[]) {
    this.delegates = [...delegates];
  }

  /** Register an additional observer (breaks the widget↔manager construction cycle). */
  add(observer: SubagentManagerObserver): void {
    this.delegates.push(observer);
  }

  onSubagentStarted(record: Subagent): void {
    this.dispatch((o) => o.onSubagentStarted(record), "onSubagentStarted");
  }

  onSubagentCreated(record: Subagent): void {
    this.dispatch((o) => o.onSubagentCreated(record), "onSubagentCreated");
  }

  onSubagentCompleted(record: Subagent): void {
    this.dispatch((o) => o.onSubagentCompleted(record), "onSubagentCompleted");
  }

  onSubagentResumedStarted(record: Subagent): void {
    this.dispatch((o) => o.onSubagentResumedStarted?.(record), "onSubagentResumedStarted");
  }

  onSubagentResumed(record: Subagent): void {
    this.dispatch((o) => o.onSubagentResumed?.(record), "onSubagentResumed");
  }

  onSubagentCleared(record: Subagent): void {
    this.dispatch((o) => o.onSubagentCleared?.(record), "onSubagentCleared");
  }

  onSubagentCompacted(record: Subagent, info: CompactionInfo): void {
    this.dispatch((o) => o.onSubagentCompacted(record, info), "onSubagentCompacted");
  }

  private dispatch(call: (o: SubagentManagerObserver) => void, label: string): void {
    for (const o of this.delegates) {
      try {
        call(o);
      } catch (err) {
        debugLog(`CompositeSubagentObserver.${label}`, err);
      }
    }
  }
}