import type {
  ExtensionAPI,
  ExtensionHandler,
  SessionStartEvent,
  SessionShutdownEvent,
  BeforeAgentStartEvent,
  BeforeAgentStartEventResult,
  InputEvent,
  InputEventResult,
  TurnEndEvent,
  RegisteredCommand,
} from "@earendil-works/pi-coding-agent";

/**
 * Sole isolation point for all Pi SDK calls.
 * No other Core file may import ExtensionAPI directly — pass PiAdapter instead.
 * This makes the Pi boundary explicit and allows tests to mock the adapter.
 *
 * Note: resources_discover is not wrapped here because its event/result types
 * are not exported from the SDK's main entry point. The gatekeeper extension
 * (a CS-specific extension being removed in Phase 5) calls pi.on directly.
 */
export class PiAdapter {
  constructor(private readonly pi: ExtensionAPI) {}

  onSessionStart(handler: ExtensionHandler<SessionStartEvent>): void {
    this.pi.on("session_start", handler);
  }

  onSessionShutdown(handler: ExtensionHandler<SessionShutdownEvent>): void {
    this.pi.on("session_shutdown", handler);
  }

  onBeforeAgentStart(
    handler: ExtensionHandler<BeforeAgentStartEvent, BeforeAgentStartEventResult>
  ): void {
    this.pi.on("before_agent_start", handler);
  }

  onInput(handler: ExtensionHandler<InputEvent, InputEventResult>): void {
    this.pi.on("input", handler);
  }

  onTurnEnd(handler: ExtensionHandler<TurnEndEvent>): void {
    this.pi.on("turn_end", handler);
  }

  registerCommand(name: string, options: Omit<RegisteredCommand, "name" | "sourceInfo">): void {
    this.pi.registerCommand(name, options);
  }

  sendUserMessage(content: string): void {
    this.pi.sendUserMessage(content);
  }
}