/**
 * Progress emitter for the orchestrator.
 *
 * The CLI prints live status as the orchestrator walks each module
 * through its state machine; tests use a capturing emitter to assert
 * on exactly which events fired in which order. Same shape as the
 * `[progress:start] / [progress:done]` pattern in
 * `packages/e2e/src/runner.ts`.
 */

import type { ModuleUpdateState, UpdateStep } from './types';

export type ProgressEvent =
  | { kind: 'plan'; modules: number }
  | { kind: 'self-update-start' }
  | { kind: 'self-update-done'; from: string; to: string }
  | { kind: 'self-update-skipped'; reason: string }
  | { kind: 'backup-start'; moduleId: string }
  | { kind: 'backup-done'; moduleId: string }
  | { kind: 'module-start'; moduleId: string; fromVersion: string; toVersion: string }
  | { kind: 'module-step'; moduleId: string; step: UpdateStep }
  | { kind: 'module-done'; state: ModuleUpdateState }
  | { kind: 'module-failed'; state: ModuleUpdateState }
  | { kind: 'module-skipped'; state: ModuleUpdateState }
  | { kind: 'run-done'; ok: boolean };

export interface ProgressEmitter {
  emit(event: ProgressEvent): void;
}

/** Default emitter — silent. Override for live console output. */
export const silentProgress: ProgressEmitter = {
  emit() {},
};

export interface CapturingEmitter extends ProgressEmitter {
  events: ProgressEvent[];
}

/** Test helper: collect every event in `events` for later assertion. */
export function capturingProgress(): CapturingEmitter {
  const events: ProgressEvent[] = [];
  return {
    events,
    emit(event) {
      events.push(event);
    },
  };
}