/**
 * Multi-Provider Agent Manager — Orchestrator
 *
 * Implementation of AgentManager port supporting multiple CLI providers.
 * Delegates to extracted helpers:
 * - ProcessManager: subprocess spawn/kill/poll, worktree creation, command building
 * - CredentialHandler: account selection, credential write/refresh, exhaustion handling
 * - OutputHandler: stream events, signal parsing, file reading, result capture
 * - CleanupManager: worktree/branch/log removal, orphan cleanup, reconciliation
 */

import type {
  AgentManager,
  AgentInfo,
  SpawnAgentOptions,
  AgentResult,
  AgentStatus,
  AgentMode,
  PendingQuestions,
} from './types.js';
import type { AgentRepository } from '../db/repositories/agent-repository.js';
import type { AccountRepository } from '../db/repositories/account-repository.js';
import type { ProjectRepository } from '../db/repositories/project-repository.js';
import type { ChangeSetRepository } from '../db/repositories/change-set-repository.js';
import type { PhaseRepository } from '../db/repositories/phase-repository.js';
import type { TaskRepository } from '../db/repositories/task-repository.js';
import type { PageRepository } from '../db/repositories/page-repository.js';
import type { LogChunkRepository } from '../db/repositories/log-chunk-repository.js';
import type { ChatSessionRepository } from '../db/repositories/chat-session-repository.js';
import type { ReviewCommentRepository } from '../db/repositories/review-comment-repository.js';
import { generateUniqueAlias } from './alias.js';
import type {
  EventBus,
  AgentSpawnedEvent,
  AgentStoppedEvent,
  AgentResumedEvent,
  AgentDeletedEvent,
  ProcessCrashedEvent,
} from '../events/index.js';
import { writeInputFiles } from './file-io.js';
import { buildWorkspaceLayout, buildInterAgentCommunication, buildPreviewInstructions } from './prompts/index.js';
import { getProvider } from './providers/registry.js';
import { createModuleLogger } from '../logger/index.js';
import { getProjectCloneDir } from '../git/project-clones.js';
import { join } from 'node:path';
import { unlink, readFile, writeFile as writeFileAsync, mkdir } from 'node:fs/promises';
import { existsSync } from 'node:fs';
import type { AccountCredentialManager } from './credentials/types.js';
import { ProcessManager } from './process-manager.js';
import { CredentialHandler } from './credential-handler.js';
import { OutputHandler, type ActiveAgent } from './output-handler.js';
import { CleanupManager } from './cleanup-manager.js';
import { createLifecycleController } from './lifecycle/factory.js';
import type { AgentLifecycleController } from './lifecycle/controller.js';
import { AgentExhaustedError, AgentFailureError } from './lifecycle/retry-policy.js';
import { FileSystemSignalManager } from './lifecycle/signal-manager.js';
import type { SignalManager } from './lifecycle/signal-manager.js';

const log = createModuleLogger('agent-manager');

export class MultiProviderAgentManager implements AgentManager {
  private static readonly MAX_COMMIT_RETRIES = 1;

  private activeAgents: Map<string, ActiveAgent> = new Map();
  private commitRetryCount: Map<string, number> = new Map();
  private processManager: ProcessManager;
  private credentialHandler: CredentialHandler;
  private outputHandler: OutputHandler;
  private cleanupManager: CleanupManager;
  private lifecycleController: AgentLifecycleController;
  private signalManager: SignalManager;

  constructor(
    private repository: AgentRepository,
    private workspaceRoot: string,
    private projectRepository: ProjectRepository,
    private accountRepository?: AccountRepository,
    private eventBus?: EventBus,
    private credentialManager?: AccountCredentialManager,
    private changeSetRepository?: ChangeSetRepository,
    private phaseRepository?: PhaseRepository,
    private taskRepository?: TaskRepository,
    private pageRepository?: PageRepository,
    private logChunkRepository?: LogChunkRepository,
    private debug: boolean = false,
    processManagerOverride?: ProcessManager,
    private chatSessionRepository?: ChatSessionRepository,
    private reviewCommentRepository?: ReviewCommentRepository,
  ) {
    this.signalManager = new FileSystemSignalManager();
    this.processManager = processManagerOverride ?? new ProcessManager(workspaceRoot, projectRepository);
    this.credentialHandler = new CredentialHandler(workspaceRoot, accountRepository, credentialManager);
    this.outputHandler = new OutputHandler(repository, eventBus, changeSetRepository, phaseRepository, taskRepository, pageRepository, this.signalManager, chatSessionRepository, reviewCommentRepository);
    this.cleanupManager = new CleanupManager(workspaceRoot, repository, projectRepository, eventBus, debug, this.signalManager);
    this.lifecycleController = createLifecycleController({
      repository,
      processManager: this.processManager,
      cleanupManager: this.cleanupManager,
      accountRepository,
      debug,
      eventBus,
    });

    // Listen for process crashed events to handle agents specially
    if (eventBus) {
      eventBus.on('process:crashed', async (event: ProcessCrashedEvent) => {
        await this.handleProcessCrashed(event.payload.processId, event.payload.exitCode, event.payload.signal);
      });
    }
  }

  /**
   * Centralized cleanup of all in-memory state for an agent.
   * Cancels polling timer, removes from activeAgents.
   * NOTE: Does NOT clear commitRetryCount — that's managed by tryAutoCleanup()
   * and explicitly by stop()/delete() to avoid resetting retries mid-cycle.
   */
  private cleanupAgentState(agentId: string): void {
    const active = this.activeAgents.get(agentId);
    if (active?.cancelPoll) active.cancelPoll();
    this.activeAgents.delete(agentId);
  }

  /**
   * Create a fire-and-forget callback for persisting raw output chunks to the DB.
   * Returns undefined if no logChunkRepository is configured.
   */
  private createLogChunkCallback(
    agentId: string,
    agentName: string,
    sessionNumber: number,
  ): ((content: string) => void) | undefined {
    const repo = this.logChunkRepository;
    if (!repo) return undefined;

    return (content) => {
      repo.insertChunk({ agentId, agentName, sessionNumber, content })
        .then(() => {
          if (this.eventBus) {
            this.eventBus.emit({
              type: 'agent:output' as const,
              timestamp: new Date(),
              payload: { agentId, stream: 'stdout', data: content },
            });
          }
        })
        .catch(err => log.warn({ agentId, err: err instanceof Error ? err.message : String(err) }, 'failed to persist log chunk'));
    };
  }

  /**
   * Spawn a new agent using the unified lifecycle controller.
   * Features comprehensive retry, error handling, and cleanup.
   */
  async spawnWithLifecycle(options: SpawnAgentOptions): Promise<AgentInfo> {
    log.info({
      taskId: options.taskId,
      provider: options.provider,
      initiativeId: options.initiativeId,
      mode: options.mode
    }, 'spawning agent with unified lifecycle management');

    let spawnedAgent: AgentInfo | undefined;
    await this.lifecycleController.spawnWithRetry(
      async (opts) => {
        const agent = await this.spawnInternal(opts);
        spawnedAgent = agent;
        return { id: agent.id, name: agent.name, status: agent.status, initiativeId: agent.initiativeId, worktreeId: agent.worktreeId };
      },
      options
    );
    return spawnedAgent!;
  }

  /**
   * Spawn a new agent to work on a task (legacy method).
   * Consider using spawnWithLifecycle for better error handling.
   */
  async spawn(options: SpawnAgentOptions): Promise<AgentInfo> {
    return this.spawnInternal(options);
  }

  /**
   * Internal spawn implementation without lifecycle management.
   * Used by both legacy spawn() and new lifecycle-managed spawn.
   */
  private async spawnInternal(options: SpawnAgentOptions): Promise<AgentInfo> {
    const { taskId, cwd, mode = 'execute', provider: providerName = 'claude', initiativeId, baseBranch, branchName } = options;
    let { prompt } = options;
    log.info({ taskId, provider: providerName, initiativeId, mode, baseBranch, branchName }, 'spawn requested');

    const provider = getProvider(providerName);
    if (!provider) {
      throw new Error(`Unknown provider: '${providerName}'. Available: claude, codex, gemini, cursor, auggie, amp, opencode`);
    }

    // Generate or validate name
    let name: string;
    if (options.name) {
      name = options.name;
      const existing = await this.repository.findByName(name);
      if (existing) {
        throw new Error(`Agent with name '${name}' already exists`);
      }
    } else {
      name = await generateUniqueAlias(this.repository);
    }
    const alias = name;
    log.debug({ alias }, 'alias generated');

    // 1. Account selection
    let accountId: string | null = null;
    let accountConfigDir: string | null = null;

    const accountResult = await this.credentialHandler.selectAccount(providerName);
    if (accountResult) {
      accountId = accountResult.accountId;
      accountConfigDir = accountResult.configDir;

      await this.credentialHandler.writeCredentialsToDisk(accountResult.account, accountConfigDir);
      const { valid, refreshed } = await this.credentialHandler.ensureCredentials(accountConfigDir, accountId);
      if (!valid) {
        log.warn({ alias, accountId }, 'failed to refresh account credentials, proceeding anyway');
      }
      if (refreshed) {
        await this.credentialHandler.persistRefreshedCredentials(accountId, accountConfigDir);
      }
    }

    if (accountId) {
      log.info({ alias, accountId }, 'account selected');
    } else {
      log.debug('no accounts available, spawning without account');
    }

    // 2. Create isolated worktrees (skip when caller provides explicit cwd, e.g. errands)
    let agentCwd: string;
    if (cwd) {
      // Caller manages the worktree (errands). Use their cwd directly.
      agentCwd = cwd;
      log.info({ alias, agentCwd }, 'using caller-provided cwd, skipping worktree creation');
    } else if (initiativeId) {
      log.debug({ alias, initiativeId, baseBranch, branchName }, 'creating initiative-based worktrees');
      agentCwd = await this.processManager.createProjectWorktrees(alias, initiativeId, baseBranch, branchName);

      // Verify each project worktree subdirectory actually exists
      const projects = await this.projectRepository.findProjectsByInitiativeId(initiativeId);
      for (const project of projects) {
        const projectWorktreePath = join(agentCwd, project.name);
        if (!existsSync(projectWorktreePath)) {
          throw new Error(
            `Worktree subdirectory missing after createProjectWorktrees: ${projectWorktreePath}. ` +
            `Agent ${alias} cannot run without an isolated worktree.`
          );
        }
      }

      log.info({
        alias,
        initiativeId,
        projectCount: projects.length,
        projects: projects.map(p => ({ name: p.name, url: p.url })),
        agentCwd
      }, 'initiative-based agent workdir created');
    } else {
      log.debug({ alias }, 'creating standalone worktree');
      agentCwd = await this.processManager.createStandaloneWorktree(alias);
      log.info({ alias, agentCwd }, 'standalone agent workdir created');
    }

    // Verify the final agentCwd exists
    if (!existsSync(agentCwd)) {
      throw new Error(`Agent workdir does not exist after creation: ${agentCwd}`);
    }
    log.info({
      alias,
      agentCwd,
      initiativeBasedAgent: !!initiativeId
    }, 'agent workdir setup completed');

    // 2b. Append workspace layout to prompt now that worktrees exist
    const workspaceSection = buildWorkspaceLayout(agentCwd);
    if (workspaceSection) {
      prompt = prompt + workspaceSection;
    }

    // 3. Create agent record
    const agent = await this.repository.create({
      name: alias,
      taskId: taskId ?? null,
      initiativeId: initiativeId ?? null,
      sessionId: null,
      worktreeId: alias,
      status: 'running',
      mode,
      provider: providerName,
      accountId,
    });
    const agentId = agent.id;

    // 3a. Append inter-agent communication + preview instructions (skipped for focused agents)
    if (!options.skipPromptExtras) {
      prompt = prompt + buildInterAgentCommunication(agentId, mode);

      if (['execute', 'refine', 'discuss'].includes(mode) && initiativeId) {
        const shouldInject = await this.shouldInjectPreviewInstructions(initiativeId);
        if (shouldInject) {
          prompt = prompt + buildPreviewInstructions(agentId);
        }
      }
    }

    // 3c. Write input files (after agent creation so we can include agentId/agentName)
    if (options.inputContext) {
      await writeInputFiles({ agentWorkdir: agentCwd, ...options.inputContext, agentId, agentName: alias });
      log.debug({ alias }, 'input files written');
    } else {
      // Always create .cw/output/ at the agent workdir root so the agent
      // writes signal.json here rather than in a project subdirectory.
      await mkdir(join(agentCwd, '.cw', 'output'), { recursive: true });
    }

    // 4. Build spawn command
    const { command, args, env: providerEnv } = this.processManager.buildSpawnCommand(provider, prompt);

    log.info({
      agentId,
      alias,
      command,
      args: args.join(' '),
      agentCwd,
      providerEnv: Object.keys(providerEnv)
    }, 'spawn command built');

    // 5. Prepare process environment with credentials
    const { processEnv } = await this.credentialHandler.prepareProcessEnv(providerEnv, provider, accountId);

    log.debug({
      agentId,
      finalProcessEnv: Object.keys(processEnv),
      hasAccountConfig: !!accountId,
      hasOAuthToken: !!processEnv['CLAUDE_CODE_OAUTH_TOKEN'],
    }, 'process environment prepared');

    // 6. Spawn detached subprocess
    const { pid, outputFilePath, tailer } = await this.processManager.spawnDetached(
      agentId, alias, command, args, agentCwd, processEnv, providerName, prompt,
      (event) => this.outputHandler.handleStreamEvent(agentId, event, this.activeAgents.get(agentId)),
      this.createLogChunkCallback(agentId, alias, 1),
    );

    await this.repository.update(agentId, { pid, outputFilePath, prompt });

    // Register agent and start polling BEFORE non-critical I/O so that a
    // diagnostic-write failure can never orphan a running process.
    const activeEntry: ActiveAgent = { agentId, pid, tailer, outputFilePath, agentCwd };
    this.activeAgents.set(agentId, activeEntry);

    // Emit spawned event
    if (this.eventBus) {
      const event: AgentSpawnedEvent = {
        type: 'agent:spawned',
        timestamp: new Date(),
        payload: { agentId, name: alias, taskId: taskId ?? null, worktreeId: alias, provider: providerName },
      };
      this.eventBus.emit(event);
    }

    // Start polling for completion
    const { cancel } = this.processManager.pollForCompletion(
      agentId, pid,
      () => this.handleDetachedAgentCompletion(agentId),
      () => this.activeAgents.get(agentId)?.tailer,
      this.createEarlyCompletionChecker(agentId),
    );
    activeEntry.cancelPoll = cancel;

    // Write spawn diagnostic file (non-fatal — .cw/ may not exist yet for
    // agents spawned without inputContext, e.g. conflict-resolution agents)
    try {
      const diagnosticDir = join(agentCwd, '.cw');
      await mkdir(diagnosticDir, { recursive: true });
      const diagnostic = {
        timestamp: new Date().toISOString(),
        agentId,
        alias,
        intendedCwd: agentCwd,
        worktreeId: agent.worktreeId,
        provider: providerName,
        command,
        args,
        env: processEnv,
        cwdExistsAtSpawn: existsSync(agentCwd),
        initiativeId: initiativeId || null,
        customCwdProvided: !!cwd,
        accountId: accountId || null,
      };
      await writeFileAsync(
        join(diagnosticDir, 'spawn-diagnostic.json'),
        JSON.stringify(diagnostic, null, 2),
        'utf-8'
      );
    } catch (err) {
      log.warn({ agentId, alias, err: err instanceof Error ? err.message : String(err) }, 'failed to write spawn diagnostic');
    }

    log.info({ agentId, alias, pid }, 'detached subprocess started');

    return this.toAgentInfo(agent);
  }

  /**
   * Create a callback that checks if an agent has a valid signal.json,
   * used by pollForCompletion to detect hung processes.
   */
  private createEarlyCompletionChecker(agentId: string): () => Promise<boolean> {
    return async () => {
      const agent = await this.repository.findById(agentId);
      if (!agent?.worktreeId) return false;
      const agentWorkdir = this.processManager.getAgentWorkdir(agent.worktreeId);
      const signal = await this.outputHandler.readSignalCompletion(agentWorkdir);
      return signal !== null;
    };
  }

  /**
   * Handle completion of a detached agent.
   */
  private async handleDetachedAgentCompletion(agentId: string): Promise<void> {
    if (!this.activeAgents.has(agentId)) return;

    const active = this.activeAgents.get(agentId);
    await this.outputHandler.handleCompletion(
      agentId,
      active,
      (alias) => this.processManager.getAgentWorkdir(alias),
    );

    // Sync credentials back to DB if the agent had an account
    await this.syncCredentialsPostCompletion(agentId);

    this.cleanupAgentState(agentId);

    // Auto-cleanup workdir after completion
    await this.tryAutoCleanup(agentId);
  }

  /**
   * Attempt auto-cleanup of agent workdir after completion.
   * If dirty and retries remain, resumes the agent to commit changes.
   */
  private async tryAutoCleanup(agentId: string): Promise<void> {
    try {
      const agent = await this.repository.findById(agentId);
      if (!agent || agent.status !== 'idle') return;

      const { clean, removed } = await this.cleanupManager.autoCleanupAfterCompletion(
        agentId, agent.name, agent.initiativeId,
      );

      if (removed) {
        this.commitRetryCount.delete(agentId);
        log.info({ agentId, alias: agent.name }, 'auto-cleanup completed');
        return;
      }

      if (!clean) {
        const retries = this.commitRetryCount.get(agentId) ?? 0;
        if (retries < MultiProviderAgentManager.MAX_COMMIT_RETRIES) {
          this.commitRetryCount.set(agentId, retries + 1);
          const resumed = await this.resumeForCommit(agentId);
          if (resumed) {
            log.info({ agentId, alias: agent.name, retry: retries + 1 }, 'resumed agent to commit uncommitted changes');
            return;
          }
        }
        log.warn({ agentId, alias: agent.name }, 'agent workdir has uncommitted changes after max retries, leaving in place');
        this.commitRetryCount.delete(agentId);
      }
    } catch (err) {
      log.warn({ agentId, err: err instanceof Error ? err.message : String(err) }, 'auto-cleanup failed');
      this.commitRetryCount.delete(agentId);
    }
  }

  /**
   * Resume an agent's session with a prompt to commit uncommitted changes.
   * Returns false if the agent can't be resumed (no session, provider doesn't support resume).
   */
  private async resumeForCommit(agentId: string): Promise<boolean> {
    const agent = await this.repository.findById(agentId);
    if (!agent?.sessionId) return false;

    const provider = getProvider(agent.provider);
    if (!provider || provider.resumeStyle === 'none') return false;

    // Check which specific worktrees are dirty — skip resume if all clean
    const dirtyPaths = await this.cleanupManager.getDirtyWorktreePaths(agent.name, agent.initiativeId);
    if (dirtyPaths.length === 0) return false;

    // Use absolute paths so the agent can't accidentally commit in the main repo
    // Use `git add -u` (tracked files only) instead of `git add -A` to avoid staging unrelated files
    const dirtyList = dirtyPaths.map(p => `- \`${p.absPath}\``).join('\n');
    const commitPrompt =
      'You have uncommitted changes in the following directories:\n' +
      dirtyList + '\n\n' +
      'For each directory listed above, `cd` into the EXACT absolute path shown, then run:\n' +
      '1. `git add -u` to stage only tracked modified files\n' +
      '2. `git commit -m "<message>"` with a message describing the work\n' +
      'Do not use `git add -A` or `git add .`. Do not stage untracked files. Do not make any other changes.';

    await this.repository.update(agentId, { status: 'running', pendingQuestions: null, result: null });

    const agentCwd = this.processManager.getAgentWorkdir(agent.worktreeId);
    const { command, args, env: providerEnv } = this.processManager.buildResumeCommand(provider, agent.sessionId, commitPrompt);

    const { processEnv } = await this.credentialHandler.prepareProcessEnv(providerEnv, provider, agent.accountId);

    const prevActive = this.activeAgents.get(agentId);
    prevActive?.cancelPoll?.();
    if (prevActive?.tailer) {
      await prevActive.tailer.stop();
    }

    // Determine session number for commit retry
    let commitSessionNumber = 1;
    if (this.logChunkRepository) {
      commitSessionNumber = (await this.logChunkRepository.getSessionCount(agentId)) + 1;
    }

    const { pid, outputFilePath, tailer } = await this.processManager.spawnDetached(
      agentId, agent.name, command, args, agentCwd, processEnv, provider.name, commitPrompt,
      (event) => this.outputHandler.handleStreamEvent(agentId, event, this.activeAgents.get(agentId)),
      this.createLogChunkCallback(agentId, agent.name, commitSessionNumber),
    );

    await this.repository.update(agentId, { pid, outputFilePath });
    const commitActiveEntry: ActiveAgent = { agentId, pid, tailer, outputFilePath };
    this.activeAgents.set(agentId, commitActiveEntry);

    const { cancel: commitCancel } = this.processManager.pollForCompletion(
      agentId, pid,
      () => this.handleDetachedAgentCompletion(agentId),
      () => this.activeAgents.get(agentId)?.tailer,
      this.createEarlyCompletionChecker(agentId),
    );
    commitActiveEntry.cancelPoll = commitCancel;

    return true;
  }

  /**
   * Resume an idle agent to answer an inter-agent conversation.
   * Returns false if the agent can't be resumed (no session, provider doesn't support resume, etc.).
   */
  private conversationResumeLocks = new Set<string>();

  async resumeForConversation(
    agentId: string,
    conversationId: string,
    question: string,
    fromAgentId: string,
  ): Promise<boolean> {
    // Concurrency guard — prevent double-resume race
    if (this.conversationResumeLocks.has(agentId)) {
      log.info({ agentId, conversationId }, 'conversation resume already in progress, skipping');
      return false;
    }

    const agent = await this.repository.findById(agentId);
    if (!agent) return false;
    if (agent.status !== 'idle') {
      log.debug({ agentId, status: agent.status }, 'agent not idle, skipping conversation resume');
      return false;
    }
    if (!agent.sessionId) {
      log.debug({ agentId }, 'no session ID, cannot resume for conversation');
      return false;
    }

    const provider = getProvider(agent.provider);
    if (!provider || provider.resumeStyle === 'none') {
      log.debug({ agentId, provider: agent.provider }, 'provider does not support resume');
      return false;
    }

    const agentCwd = this.processManager.getAgentWorkdir(agent.worktreeId);
    if (!existsSync(agentCwd)) {
      log.debug({ agentId, agentCwd }, 'worktree no longer exists, cannot resume');
      return false;
    }

    this.conversationResumeLocks.add(agentId);
    try {
      const conversationPrompt =
        `Another agent (ID: ${fromAgentId}) asked you a question via inter-agent communication.\n\n` +
        `**Conversation ID**: ${conversationId}\n` +
        `**Question**: ${question}\n\n` +
        `Please answer this question using:\n` +
        `  cw answer "<your answer>" --conversation-id ${conversationId}\n\n` +
        `After answering, check for any other pending conversations:\n` +
        `  cw listen --agent-id ${agentId}\n\n` +
        `Answer any additional pending conversations the same way, then complete your session.`;

      // Clear previous signal.json
      const signalPath = join(agentCwd, '.cw/output/signal.json');
      try {
        await unlink(signalPath);
      } catch {
        // File might not exist
      }

      await this.repository.update(agentId, { status: 'running', pendingQuestions: null, result: null });

      const { command, args, env: providerEnv } = this.processManager.buildResumeCommand(provider, agent.sessionId, conversationPrompt);
      const { processEnv } = await this.credentialHandler.prepareProcessEnv(providerEnv, provider, agent.accountId);

      // Stop previous tailer/poll
      const prevActive = this.activeAgents.get(agentId);
      prevActive?.cancelPoll?.();
      if (prevActive?.tailer) {
        await prevActive.tailer.stop();
      }

      let sessionNumber = 1;
      if (this.logChunkRepository) {
        sessionNumber = (await this.logChunkRepository.getSessionCount(agentId)) + 1;
      }

      const { pid, outputFilePath, tailer } = await this.processManager.spawnDetached(
        agentId, agent.name, command, args, agentCwd, processEnv, provider.name, conversationPrompt,
        (event) => this.outputHandler.handleStreamEvent(agentId, event, this.activeAgents.get(agentId)),
        this.createLogChunkCallback(agentId, agent.name, sessionNumber),
      );

      await this.repository.update(agentId, { pid, outputFilePath });
      const activeEntry: ActiveAgent = { agentId, pid, tailer, outputFilePath };
      this.activeAgents.set(agentId, activeEntry);

      if (this.eventBus) {
        // verified: payload matches AgentResumedEvent shape (agentId, name, taskId, sessionId)
        const event: AgentResumedEvent = {
          type: 'agent:resumed',
          timestamp: new Date(),
          payload: { agentId, name: agent.name, taskId: agent.taskId ?? '', sessionId: agent.sessionId },
        };
        this.eventBus.emit(event);
      }

      const { cancel } = this.processManager.pollForCompletion(
        agentId, pid,
        () => this.handleDetachedAgentCompletion(agentId),
        () => this.activeAgents.get(agentId)?.tailer,
        this.createEarlyCompletionChecker(agentId),
      );
      activeEntry.cancelPoll = cancel;

      log.info({ agentId, conversationId, pid }, 'resumed idle agent for conversation');
      return true;
    } finally {
      this.conversationResumeLocks.delete(agentId);
    }
  }

  /**
   * Deliver a user message to a running or idle errand agent.
   * Does not use the conversations table — the message is injected directly
   * as the next resume prompt for the agent's Claude Code session.
   */
  async sendUserMessage(agentId: string, message: string, cwd?: string): Promise<void> {
    const agent = await this.repository.findById(agentId);
    if (!agent) throw new Error(`Agent not found: ${agentId}`);

    if (agent.status !== 'running' && agent.status !== 'idle') {
      throw new Error(`Agent is not running (status: ${agent.status})`);
    }

    if (!agent.sessionId) {
      throw new Error('Agent has no session ID');
    }

    const provider = getProvider(agent.provider);
    if (!provider) throw new Error(`Unknown provider: ${agent.provider}`);

    const agentCwd = cwd ?? this.processManager.getAgentWorkdir(agent.worktreeId);

    // Clear previous signal.json
    const signalPath = join(agentCwd, '.cw/output/signal.json');
    try {
      await unlink(signalPath);
    } catch {
      // File might not exist
    }

    await this.repository.update(agentId, { status: 'running', result: null });

    const { command, args, env: providerEnv } = this.processManager.buildResumeCommand(provider, agent.sessionId, message);
    const { processEnv } = await this.credentialHandler.prepareProcessEnv(providerEnv, provider, agent.accountId);

    // Stop previous tailer/poll
    const prevActive = this.activeAgents.get(agentId);
    prevActive?.cancelPoll?.();
    if (prevActive?.tailer) {
      await prevActive.tailer.stop();
    }

    let sessionNumber = 1;
    if (this.logChunkRepository) {
      sessionNumber = (await this.logChunkRepository.getSessionCount(agentId)) + 1;
    }

    const { pid, outputFilePath, tailer } = await this.processManager.spawnDetached(
      agentId, agent.name, command, args, agentCwd, processEnv, provider.name, message,
      (event) => this.outputHandler.handleStreamEvent(agentId, event, this.activeAgents.get(agentId)),
      this.createLogChunkCallback(agentId, agent.name, sessionNumber),
    );

    await this.repository.update(agentId, { pid, outputFilePath });
    const activeEntry: ActiveAgent = { agentId, pid, tailer, outputFilePath };
    this.activeAgents.set(agentId, activeEntry);

    const { cancel } = this.processManager.pollForCompletion(
      agentId, pid,
      () => this.handleDetachedAgentCompletion(agentId),
      () => this.activeAgents.get(agentId)?.tailer,
      this.createEarlyCompletionChecker(agentId),
    );
    activeEntry.cancelPoll = cancel;

    log.info({ agentId, pid }, 'resumed errand agent for user message');
  }

  /**
   * Sync credentials from agent's config dir back to DB after completion.
   * The subprocess may have refreshed tokens mid-session; this ensures
   * the DB stays current and the next spawn uses fresh tokens.
   */
  private async syncCredentialsPostCompletion(agentId: string): Promise<void> {
    if (!this.accountRepository) return;

    try {
      const agent = await this.repository.findById(agentId);
      if (!agent?.accountId) return;

      const { getAccountConfigDir } = await import('./accounts/paths.js');
      const configDir = getAccountConfigDir(this.workspaceRoot, agent.accountId);
      await this.credentialHandler.persistRefreshedCredentials(agent.accountId, configDir);
      log.debug({ agentId, accountId: agent.accountId }, 'post-completion credential sync done');
    } catch (err) {
      log.warn({ agentId, err: err instanceof Error ? err.message : String(err) }, 'post-completion credential sync failed');
    }
  }

  /**
   * Stop a running agent.
   */
  async stop(agentId: string): Promise<void> {
    const agent = await this.repository.findById(agentId);
    if (!agent) throw new Error(`Agent '${agentId}' not found`);
    log.info({ agentId, name: agent.name }, 'stopping agent');

    const active = this.activeAgents.get(agentId);
    if (active) {
      try { process.kill(active.pid, 'SIGTERM'); } catch { /* already exited */ }
      await active.tailer.stop();
    }
    this.cleanupAgentState(agentId);
    this.commitRetryCount.delete(agentId);

    // Sync credentials before marking stopped
    await this.syncCredentialsPostCompletion(agentId);

    await this.repository.update(agentId, { status: 'stopped', pendingQuestions: null });

    if (this.eventBus) {
      const event: AgentStoppedEvent = {
        type: 'agent:stopped',
        timestamp: new Date(),
        payload: { agentId, name: agent.name, taskId: agent.taskId ?? '', reason: 'user_requested' },
      };
      this.eventBus.emit(event);
    }
  }

  /**
   * List all agents with their current status.
   */
  async list(): Promise<AgentInfo[]> {
    const agents = await this.repository.findAll();
    return agents.map((a) => this.toAgentInfo(a));
  }

  /**
   * Get a specific agent by ID.
   */
  async get(agentId: string): Promise<AgentInfo | null> {
    const agent = await this.repository.findById(agentId);
    return agent ? this.toAgentInfo(agent) : null;
  }

  /**
   * Get a specific agent by name.
   */
  async getByName(name: string): Promise<AgentInfo | null> {
    const agent = await this.repository.findByName(name);
    return agent ? this.toAgentInfo(agent) : null;
  }

  /**
   * Resume an agent using the unified lifecycle controller.
   * Features comprehensive retry, error handling, and cleanup.
   */
  async resumeWithLifecycle(agentId: string, answers: Record<string, string>): Promise<void> {
    log.info({
      agentId,
      answerKeys: Object.keys(answers)
    }, 'resuming agent with unified lifecycle management');

    await this.lifecycleController.resumeWithRetry(
      (id, modifiedAnswers) => this.resumeInternal(id, modifiedAnswers),
      { agentId, answers }
    );
  }

  /**
   * Resume an agent that's waiting for input (legacy method).
   * Consider using resumeWithLifecycle for better error handling.
   */
  async resume(agentId: string, answers: Record<string, string>): Promise<void> {
    return this.resumeInternal(agentId, answers);
  }

  /**
   * Internal resume implementation without lifecycle management.
   * Used by both legacy resume() and new lifecycle-managed resume.
   */
  private async resumeInternal(agentId: string, answers: Record<string, string>): Promise<void> {
    const agent = await this.repository.findById(agentId);
    if (!agent) throw new Error(`Agent '${agentId}' not found`);
    if (agent.status !== 'waiting_for_input') {
      throw new Error(`Agent '${agent.name}' is not waiting for input (status: ${agent.status})`);
    }
    if (!agent.sessionId) {
      throw new Error(`Agent '${agent.name}' has no session to resume`);
    }
    log.info({ agentId, sessionId: agent.sessionId, provider: agent.provider }, 'resuming agent');

    const provider = getProvider(agent.provider);
    if (!provider) throw new Error(`Unknown provider: '${agent.provider}'`);
    if (provider.resumeStyle === 'none') {
      throw new Error(`Provider '${provider.name}' does not support resume`);
    }

    const agentCwd = this.processManager.getAgentWorkdir(agent.worktreeId);
    const prompt = this.outputHandler.formatAnswersAsPrompt(answers);

    // Clear previous signal.json to ensure clean completion detection
    const signalPath = join(agentCwd, '.cw/output/signal.json');
    try {
      await unlink(signalPath);
      log.debug({ agentId, signalPath }, 'cleared previous signal.json for resume');
    } catch {
      // File might not exist, which is fine
    }

    await this.repository.update(agentId, { status: 'running', pendingQuestions: null, result: null });

    const { command, args, env: providerEnv } = this.processManager.buildResumeCommand(provider, agent.sessionId, prompt);
    log.debug({ command, args: args.join(' ') }, 'resume command built');

    // Prepare process environment with credentials
    const { processEnv } = await this.credentialHandler.prepareProcessEnv(providerEnv, provider, agent.accountId);

    // Stop previous tailer and cancel previous poll
    const prevActive = this.activeAgents.get(agentId);
    prevActive?.cancelPoll?.();
    if (prevActive?.tailer) {
      await prevActive.tailer.stop();
    }

    // Determine session number for this resume
    let resumeSessionNumber = 1;
    if (this.logChunkRepository) {
      resumeSessionNumber = (await this.logChunkRepository.getSessionCount(agentId)) + 1;
    }

    const { pid, outputFilePath, tailer } = await this.processManager.spawnDetached(
      agentId, agent.name, command, args, agentCwd, processEnv, provider.name, prompt,
      (event) => this.outputHandler.handleStreamEvent(agentId, event, this.activeAgents.get(agentId)),
      this.createLogChunkCallback(agentId, agent.name, resumeSessionNumber),
    );

    await this.repository.update(agentId, { pid, outputFilePath });

    const resumeActiveEntry: ActiveAgent = { agentId, pid, tailer, outputFilePath };
    this.activeAgents.set(agentId, resumeActiveEntry);
    log.info({ agentId, pid }, 'resume detached subprocess started');

    if (this.eventBus) {
      // verified: payload matches AgentResumedEvent shape (agentId, name, taskId, sessionId)
      const event: AgentResumedEvent = {
        type: 'agent:resumed',
        timestamp: new Date(),
        payload: { agentId, name: agent.name, taskId: agent.taskId ?? '', sessionId: agent.sessionId },
      };
      this.eventBus.emit(event);
    }

    const { cancel: resumeCancel } = this.processManager.pollForCompletion(
      agentId, pid,
      () => this.handleDetachedAgentCompletion(agentId),
      () => this.activeAgents.get(agentId)?.tailer,
      this.createEarlyCompletionChecker(agentId),
    );
    resumeActiveEntry.cancelPoll = resumeCancel;
  }

  /**
   * Get the result of an agent's work.
   */
  async getResult(agentId: string): Promise<AgentResult | null> {
    return this.outputHandler.getResult(agentId, this.activeAgents.get(agentId));
  }

  /**
   * Get pending questions for an agent waiting for input.
   */
  async getPendingQuestions(agentId: string): Promise<PendingQuestions | null> {
    return this.outputHandler.getPendingQuestions(agentId, this.activeAgents.get(agentId));
  }

  /**
   * Delete an agent and clean up all associated resources.
   */
  async delete(agentId: string): Promise<void> {
    const agent = await this.repository.findById(agentId);
    if (!agent) throw new Error(`Agent '${agentId}' not found`);
    log.info({ agentId, name: agent.name }, 'deleting agent');

    // 1. Kill process, stop tailer, clear all in-memory state
    const active = this.activeAgents.get(agentId);
    if (active) {
      try { process.kill(active.pid, 'SIGTERM'); } catch { /* already exited */ }
      await active.tailer.stop();
    }
    this.cleanupAgentState(agentId);
    this.commitRetryCount.delete(agentId);

    // 2. Best-effort cleanup
    try { await this.cleanupManager.removeAgentWorktrees(agent.name, agent.initiativeId); }
    catch (err) { log.warn({ agentId, err: err instanceof Error ? err.message : String(err) }, 'failed to remove worktrees'); }

    try { await this.cleanupManager.removeAgentBranches(agent.name, agent.initiativeId); }
    catch (err) { log.warn({ agentId, err: err instanceof Error ? err.message : String(err) }, 'failed to remove branches'); }

    try { await this.cleanupManager.removeAgentLogs(agent.name); }
    catch (err) { log.warn({ agentId, err: err instanceof Error ? err.message : String(err) }, 'failed to remove logs'); }

    // 3b. Delete log chunks from DB
    if (this.logChunkRepository) {
      try { await this.logChunkRepository.deleteByAgentId(agentId); }
      catch (err) { log.warn({ agentId, err: err instanceof Error ? err.message : String(err) }, 'failed to delete log chunks'); }
    }

    // 4. Delete DB record
    await this.repository.delete(agentId);

    // 5. Emit deleted event
    if (this.eventBus) {
      const event: AgentDeletedEvent = {
        type: 'agent:deleted',
        timestamp: new Date(),
        payload: { agentId, name: agent.name },
      };
      this.eventBus.emit(event);
    }
    log.info({ agentId, name: agent.name }, 'agent deleted');
  }

  /**
   * Dismiss an agent.
   */
  async dismiss(agentId: string): Promise<void> {
    const agent = await this.repository.findById(agentId);
    if (!agent) throw new Error(`Agent '${agentId}' not found`);
    log.info({ agentId, name: agent.name }, 'dismissing agent');

    this.cleanupAgentState(agentId);
    this.commitRetryCount.delete(agentId);

    // Best-effort filesystem cleanup
    try { await this.cleanupManager.removeAgentWorktrees(agent.name, agent.initiativeId); }
    catch (err) { log.warn({ agentId, err: err instanceof Error ? err.message : String(err) }, 'dismiss: failed to remove worktrees'); }

    try { await this.cleanupManager.removeAgentBranches(agent.name, agent.initiativeId); }
    catch (err) { log.warn({ agentId, err: err instanceof Error ? err.message : String(err) }, 'dismiss: failed to remove branches'); }

    try { await this.cleanupManager.removeAgentLogs(agent.name); }
    catch (err) { log.warn({ agentId, err: err instanceof Error ? err.message : String(err) }, 'dismiss: failed to remove logs'); }

    await this.repository.update(agentId, {
      userDismissedAt: new Date(),
      updatedAt: new Date(),
    });

    log.info({ agentId, name: agent.name }, 'agent dismissed');
  }

  /**
   * Clean up orphaned agent workdirs.
   */
  async cleanupOrphanedWorkdirs(): Promise<void> {
    return this.cleanupManager.cleanupOrphanedWorkdirs();
  }

  /**
   * Clean up orphaned agent log directories.
   */
  async cleanupOrphanedLogs(): Promise<void> {
    return this.cleanupManager.cleanupOrphanedLogs();
  }

  /**
   * Reconcile agent state after server restart.
   */
  async reconcileAfterRestart(): Promise<void> {
    const reconcileLogChunkRepo = this.logChunkRepository;
    await this.cleanupManager.reconcileAfterRestart(
      this.activeAgents,
      (agentId, event) => this.outputHandler.handleStreamEvent(agentId, event, this.activeAgents.get(agentId)),
      (agentId, rawOutput, provider) => this.outputHandler.processAgentOutput(agentId, rawOutput, provider, (alias) => this.processManager.getAgentWorkdir(alias)),
      (agentId, pid) => {
        const { cancel } = this.processManager.pollForCompletion(
          agentId, pid,
          () => this.handleDetachedAgentCompletion(agentId),
          () => this.activeAgents.get(agentId)?.tailer,
          this.createEarlyCompletionChecker(agentId),
        );
        const active = this.activeAgents.get(agentId);
        if (active) active.cancelPoll = cancel;
      },
      reconcileLogChunkRepo
        ? (agentId, agentName, content) => {
            // Determine session number asynchronously — use fire-and-forget
            reconcileLogChunkRepo.getSessionCount(agentId).then(count => {
              return reconcileLogChunkRepo.insertChunk({
                agentId,
                agentName,
                sessionNumber: count + 1,
                content,
              });
            }).catch(err => log.warn({ agentId, err: err instanceof Error ? err.message : String(err) }, 'failed to persist log chunk during reconciliation'));
          }
        : undefined,
    );
  }

  /**
   * Handle process crashed event specifically for agents.
   * Check if the agent actually completed successfully despite the non-zero exit code.
   */
  private async handleProcessCrashed(processId: string, exitCode: number | null, signal: string | null): Promise<void> {
    try {
      // Check if this is an agent process
      const agent = await this.repository.findById(processId);
      if (!agent) {
        return; // Not our agent
      }

      // Store exit code and signal for debugging
      await this.repository.update(processId, { exitCode });

      log.info({
        agentId: processId,
        name: agent.name,
        exitCode,
        signal,
        outputFilePath: agent.outputFilePath
      }, 'agent process crashed, analyzing completion status');

      // Check if the agent has output that indicates successful completion
      if (agent.outputFilePath) {
        const hasCompletion = await this.checkAgentCompletionResult(agent.worktreeId);
        if (hasCompletion) {
          log.info({
            agentId: processId,
            name: agent.name,
            exitCode,
            signal
          }, 'agent marked as crashed but completed successfully - completion already handled by polling');

          // Note: We don't call handleCompletion() here because the polling handler
          // (handleDetachedAgentCompletion) already processes completions. The mutex
          // in OutputHandler.handleCompletion() prevents duplicate processing.

          log.info({
            agentId: processId,
            name: agent.name,
            exitCode
          }, 'completion detection confirmed - deferring to polling handler');
        } else {
          log.warn({
            agentId: processId,
            name: agent.name,
            exitCode,
            signal,
            outputFilePath: agent.outputFilePath
          }, 'agent crashed and no successful completion detected - marking as truly crashed');

          // Only mark as crashed if agent truly crashed (no completion detected)
          await this.repository.update(processId, { status: 'crashed' });
        }
      } else {
        log.warn({
          agentId: processId,
          name: agent.name,
          exitCode,
          signal
        }, 'agent crashed with no output file path - marking as crashed');

        await this.repository.update(processId, { status: 'crashed' });
      }
    } catch (err) {
      log.error({
        processId,
        exitCode,
        signal,
        err: err instanceof Error ? err.message : String(err)
      }, 'failed to check agent completion after crash');
    }
  }

  /**
   * Check if agent completed successfully by reading signal.json file.
   * Probes the workspace/ subdirectory for standalone agents.
   */
  private async checkAgentCompletionResult(worktreeId: string): Promise<boolean> {
    try {
      // Resolve actual agent workdir — standalone agents have .cw inside workspace/ subdir
      let agentWorkdir = this.processManager.getAgentWorkdir(worktreeId);
      const workspaceSub = join(agentWorkdir, 'workspace');
      if (!existsSync(join(agentWorkdir, '.cw', 'output')) && existsSync(join(workspaceSub, '.cw'))) {
        agentWorkdir = workspaceSub;
      }

      const signalPath = join(agentWorkdir, '.cw/output/signal.json');

      if (!existsSync(signalPath)) {
        log.debug({ worktreeId, signalPath }, 'no signal.json found - agent not completed');
        return false;
      }

      const signalContent = await readFile(signalPath, 'utf-8');
      const signal = JSON.parse(signalContent);

      // Agent completed if status is done, questions, or error
      const completed = signal.status === 'done' || signal.status === 'questions' || signal.status === 'error';

      if (completed) {
        log.debug({ worktreeId, signal }, 'agent completion detected via signal.json');
      } else {
        log.debug({ worktreeId, signal }, 'signal.json found but status indicates incomplete');
      }

      return completed;

    } catch (err) {
      log.warn({ worktreeId, err: err instanceof Error ? err.message : String(err) }, 'failed to read or parse signal.json');
      return false;
    }
  }

  /**
   * Check whether preview instructions should be injected for this initiative.
   * Returns true if exactly one project linked and it has .cw-preview.yml.
   */
  private async shouldInjectPreviewInstructions(initiativeId: string): Promise<boolean> {
    try {
      const projects = await this.projectRepository.findProjectsByInitiativeId(initiativeId);
      if (projects.length !== 1) return false;

      const project = projects[0];
      const cloneDir = join(this.workspaceRoot, getProjectCloneDir(project.name, project.id));
      return existsSync(join(cloneDir, '.cw-preview.yml'));
    } catch {
      return false;
    }
  }

  /**
   * Convert database agent record to AgentInfo.
   */
  private toAgentInfo(agent: {
    id: string;
    name: string;
    taskId: string | null;
    initiativeId: string | null;
    sessionId: string | null;
    worktreeId: string;
    status: string;
    mode: string;
    provider: string;
    accountId: string | null;
    createdAt: Date;
    updatedAt: Date;
    userDismissedAt?: Date | null;
    exitCode?: number | null;
    prompt?: string | null;
  }): AgentInfo {
    return {
      id: agent.id,
      name: agent.name,
      taskId: agent.taskId ?? '',
      initiativeId: agent.initiativeId,
      sessionId: agent.sessionId,
      worktreeId: agent.worktreeId,
      status: agent.status as AgentStatus,
      mode: agent.mode as AgentMode,
      provider: agent.provider,
      accountId: agent.accountId,
      createdAt: agent.createdAt,
      updatedAt: agent.updatedAt,
      userDismissedAt: agent.userDismissedAt,
      exitCode: agent.exitCode ?? null,
      prompt: agent.prompt ?? null,
    };
  }
}