/**
 * Full-Flow Test Harness
 *
 * Wires up the complete system with real agents for end-to-end multi-agent
 * workflow testing: discuss → plan → detail → execute.
 *
 * Unlike the standard TestHarness (MockAgentManager) or RealProviderHarness
 * (agents only), this harness adds:
 *  - All 11 repositories
 *  - tRPC caller for architect/agent procedures
 *  - A self-contained fixture git repo (todo-api) for agents to work on
 *  - Helpers for driving agents through question/answer loops
 *
 * Used by full-flow-cassette.test.ts (replay) and for manual recording runs.
 */

import { mkdtemp, rm, cp } from 'node:fs/promises';
import { tmpdir } from 'node:os';
import { join, dirname } from 'node:path';
import { fileURLToPath } from 'node:url';
import { execSync } from 'node:child_process';
import type { DrizzleDatabase } from '../../../db/index.js';
import type { DomainEvent } from '../../../events/types.js';
import { EventEmitterBus } from '../../../events/bus.js';
import { MultiProviderAgentManager } from '../../../agent/manager.js';
import type { AgentResult, PendingQuestions } from '../../../agent/types.js';
import type { Initiative, Project, Phase, Task } from '../../../db/schema.js';
import type { InitiativeRepository } from '../../../db/repositories/initiative-repository.js';
import type { PhaseRepository } from '../../../db/repositories/phase-repository.js';
import type { TaskRepository } from '../../../db/repositories/task-repository.js';
import type { MessageRepository } from '../../../db/repositories/message-repository.js';
import type { AgentRepository } from '../../../db/repositories/agent-repository.js';
import type { PageRepository } from '../../../db/repositories/page-repository.js';
import type { ProjectRepository } from '../../../db/repositories/project-repository.js';
import type { AccountRepository } from '../../../db/repositories/account-repository.js';
import type { ChangeSetRepository } from '../../../db/repositories/change-set-repository.js';
import type { LogChunkRepository } from '../../../db/repositories/log-chunk-repository.js';
import type { ConversationRepository } from '../../../db/repositories/conversation-repository.js';
import type { ProcessManager } from '../../../agent/process-manager.js';
import { createTestDatabase } from '../../../db/repositories/drizzle/test-helpers.js';
import { createRepositories } from '../../../container.js';
import { DefaultDispatchManager } from '../../../dispatch/manager.js';
import { appRouter, createCallerFactory } from '../../../trpc/router.js';
import { createContext } from '../../../trpc/context.js';

// =============================================================================
// CapturingEventBus
// =============================================================================

export class CapturingEventBus extends EventEmitterBus {
  emittedEvents: DomainEvent[] = [];

  emit<T extends DomainEvent>(event: T): void {
    this.emittedEvents.push(event);
    super.emit(event);
  }

  getEventsByType<T extends DomainEvent>(type: T['type']): T[] {
    return this.emittedEvents.filter((e) => e.type === type) as T[];
  }

  clearEvents(): void {
    this.emittedEvents = [];
  }
}

// =============================================================================
// Sleep helper
// =============================================================================

export function sleep(ms: number): Promise<void> {
  return new Promise((resolve) => setTimeout(resolve, ms));
}

// =============================================================================
// tRPC caller type
// =============================================================================

const createCaller = createCallerFactory(appRouter);
export type FullFlowCaller = ReturnType<typeof createCaller>;

// =============================================================================
// FullFlowHarness interface
// =============================================================================

/** Status of an agent that requires attention: done, waiting for answers, or crashed */
export type AgentAttentionStatus = 'done' | 'waiting' | 'crashed';

export interface FullFlowHarness {
  /** Absolute path to the CW workspace (worktrees are created here) */
  workspaceRoot: string;
  /** Absolute path to the cloned todo-api fixture git repo */
  fixtureRoot: string;
  /** The registered todo-api project */
  project: Project;
  /** The initiative created for the test run */
  initiative: Initiative;
  /** tRPC caller (all procedures available) */
  caller: FullFlowCaller;
  /** Real MultiProviderAgentManager */
  agentManager: MultiProviderAgentManager;
  /** In-memory SQLite database */
  db: DrizzleDatabase;
  /** Event bus with capture capability */
  eventBus: CapturingEventBus;

  // All 11 repositories
  initiativeRepository: InitiativeRepository;
  phaseRepository: PhaseRepository;
  taskRepository: TaskRepository;
  messageRepository: MessageRepository;
  agentRepository: AgentRepository;
  pageRepository: PageRepository;
  projectRepository: ProjectRepository;
  accountRepository: AccountRepository;
  changeSetRepository: ChangeSetRepository;
  logChunkRepository: LogChunkRepository;
  conversationRepository: ConversationRepository;

  /**
   * Wait for an agent to reach a terminal status (idle/stopped/crashed).
   * Returns null if the agent enters waiting_for_input.
   */
  waitForAgentCompletion(agentId: string, timeoutMs?: number): Promise<AgentResult | null>;

  /**
   * Poll until the agent needs attention: done (idle/stopped), waiting for input, or crashed.
   * Useful for the question/answer loop in discuss mode.
   */
  waitForAgentAttention(agentId: string, timeoutMs?: number): Promise<AgentAttentionStatus>;

  /**
   * Drive an agent to full completion, answering any questions along the way.
   * Answers all questions with the provided answer string (or a default).
   */
  driveToCompletion(
    agentId: string,
    answer?: string,
    timeoutMs?: number,
  ): Promise<AgentResult | null>;

  /**
   * Get captured events filtered by type.
   */
  getEventsByType<T extends DomainEvent>(type: T['type']): T[];

  /**
   * Kill all running agents and remove temp directories.
   */
  cleanup(): Promise<void>;
}

// =============================================================================
// Poll interval
// =============================================================================

const POLL_INTERVAL_MS = 1500;

// =============================================================================
// Factory
// =============================================================================

const __dirname = dirname(fileURLToPath(import.meta.url));
const FIXTURES_DIR = join(__dirname, '../../fixtures/todo-api');

export interface FullFlowHarnessOptions {
  /** Factory called after workspaceRoot + repos are created. Return a custom ProcessManager. */
  processManagerFactory?: (workspaceRoot: string, projectRepo: ProjectRepository) => ProcessManager;
}

/**
 * Create a full-flow test harness.
 *
 * Setup steps:
 *  1. Copy todo-api fixture into a temp git repo (fixtureRoot).
 *  2. Create workspace temp dir (workspaceRoot) for CW operations.
 *  3. Init in-memory DB + all 11 repos.
 *  4. Wire real MultiProviderAgentManager with all repos.
 *  5. Wire DefaultDispatchManager for execute stage.
 *  6. Create tRPC caller with full context.
 *  7. Register project in DB directly (url = fixtureRoot).
 *  8. Create initiative via tRPC (links project, creates root page).
 */
export async function createFullFlowHarness(
  initiativeName = 'Add complete() method to TodoStore',
  options?: FullFlowHarnessOptions,
): Promise<FullFlowHarness> {
  // ── 0. Allow nested claude invocations ────────────────────────────────────
  // Claude Code sets CLAUDECODE in the environment, which prevents nested
  // claude CLI calls from starting ("cannot be launched inside another Claude
  // Code session").  Save and remove it so spawned agents can run normally.
  // It is restored in cleanup().
  const savedClaudeCodeEnv = process.env.CLAUDECODE;
  delete process.env.CLAUDECODE;

  // ── 1. Fixture project ────────────────────────────────────────────────────
  // IMPORTANT: cp(src, dest) puts src INSIDE dest when dest already exists
  // (like `cp -r src dest/` → creates dest/src/).  We need dest to NOT exist
  // yet so that cp creates it as a copy of src directly.
  const fixtureBase = await mkdtemp(join(tmpdir(), 'cw-fixture-'));
  const fixtureRoot = join(fixtureBase, 'todo-api'); // does not exist yet
  await cp(FIXTURES_DIR, fixtureRoot, { recursive: true });

  // Verify files landed at the right level before git operations
  execSync(`test -f "${join(fixtureRoot, 'package.json')}"`, { stdio: 'pipe' });

  execSync('git init', { cwd: fixtureRoot, stdio: 'pipe' });
  execSync('git config user.email "test@test.com"', { cwd: fixtureRoot, stdio: 'pipe' });
  execSync('git config user.name "Test"', { cwd: fixtureRoot, stdio: 'pipe' });
  execSync('git add .', { cwd: fixtureRoot, stdio: 'pipe' });
  execSync('git commit -m "initial todo-api with missing complete()"', {
    cwd: fixtureRoot,
    stdio: 'pipe',
  });

  // ── 2. Workspace root ─────────────────────────────────────────────────────
  // Just a plain temp directory — agent worktrees live under repos/ inside it.
  // No git init needed; the PROJECT clone (repos/<name>-<id>/) is the git repo.
  const workspaceRoot = await mkdtemp(join(tmpdir(), 'cw-workspace-'));

  // ── 3. Database + repositories ────────────────────────────────────────────
  const db = createTestDatabase();
  const repos = createRepositories(db);

  // ── 4. Event bus ──────────────────────────────────────────────────────────
  const eventBus = new CapturingEventBus();

  // ── 5. Real agent manager ─────────────────────────────────────────────────
  const customProcessManager = options?.processManagerFactory?.(workspaceRoot, repos.projectRepository);
  const agentManager = new MultiProviderAgentManager(
    repos.agentRepository,
    workspaceRoot,
    repos.projectRepository,
    repos.accountRepository,
    eventBus,
    undefined, // no credential manager needed for default claude account
    repos.changeSetRepository,
    repos.phaseRepository,
    repos.taskRepository,
    repos.pageRepository,
    repos.logChunkRepository,
    false,                 // debug
    customProcessManager,  // processManagerOverride
  );

  // ── 6. Dispatch manager (for execute stage) ───────────────────────────────
  const dispatchManager = new DefaultDispatchManager(
    repos.taskRepository,
    repos.messageRepository,
    agentManager,
    eventBus,
    repos.initiativeRepository,
    repos.phaseRepository,
  );

  // ── 7. tRPC caller ────────────────────────────────────────────────────────
  const ctx = createContext({
    eventBus,
    serverStartedAt: new Date(),
    processCount: 0,
    agentManager,
    dispatchManager,
    workspaceRoot,
    ...repos,
  });
  const caller = createCaller(ctx);

  // ── 8. Register project directly in DB (bypass tRPC clone) ───────────────
  const project = await repos.projectRepository.create({
    name: 'todo-api',
    url: fixtureRoot,
  });

  // ── 9. Create initiative via tRPC (creates root page automatically) ───────
  const initiative = await caller.createInitiative({
    name: initiativeName,
    projectIds: [project.id],
  });

  // ── Helpers ───────────────────────────────────────────────────────────────

  async function waitForAgentCompletion(
    agentId: string,
    timeoutMs = 120_000,
  ): Promise<AgentResult | null> {
    const deadline = Date.now() + timeoutMs;
    while (Date.now() < deadline) {
      const agent = await repos.agentRepository.findById(agentId);
      if (!agent) return null;
      if (agent.status === 'idle' || agent.status === 'stopped' || agent.status === 'crashed') {
        return agentManager.getResult(agentId);
      }
      if (agent.status === 'waiting_for_input') return null;
      await sleep(POLL_INTERVAL_MS);
    }
    throw new Error(`Timeout: agent ${agentId} did not complete within ${timeoutMs}ms`);
  }

  async function waitForAgentAttention(
    agentId: string,
    timeoutMs = 120_000,
  ): Promise<AgentAttentionStatus> {
    const deadline = Date.now() + timeoutMs;
    while (Date.now() < deadline) {
      const agent = await repos.agentRepository.findById(agentId);
      if (!agent) return 'crashed';
      if (agent.status === 'idle' || agent.status === 'stopped') return 'done';
      if (agent.status === 'crashed') return 'crashed';
      if (agent.status === 'waiting_for_input') return 'waiting';
      await sleep(POLL_INTERVAL_MS);
    }
    throw new Error(`Timeout: agent ${agentId} did not reach attention state within ${timeoutMs}ms`);
  }

  async function driveToCompletion(
    agentId: string,
    answer = 'Use your best judgment and keep it simple.',
    timeoutMs = 10 * 60_000,
  ): Promise<AgentResult | null> {
    const deadline = Date.now() + timeoutMs;

    while (Date.now() < deadline) {
      const remaining = deadline - Date.now();
      if (remaining <= 0) break;

      let status: AgentAttentionStatus;
      try {
        status = await waitForAgentAttention(agentId, Math.min(remaining, 3 * 60_000));
      } catch {
        // Agent is still running (hasn't reached an attention state within the polling
        // window). This is normal for long-running execute agents. Continue the outer
        // loop — the deadline check above will terminate us if we truly time out.
        continue;
      }

      if (status === 'done' || status === 'crashed') {
        return agentManager.getResult(agentId);
      }

      if (status === 'waiting') {
        const pending = await agentManager.getPendingQuestions(agentId);
        if (!pending || pending.questions.length === 0) {
          // Shouldn't happen, but guard against it
          await sleep(POLL_INTERVAL_MS);
          continue;
        }
        const answers = Object.fromEntries(
          pending.questions.map((q) => [q.id, answer]),
        );
        await agentManager.resume(agentId, answers);
      }
    }

    throw new Error(`driveToCompletion: agent ${agentId} did not finish within ${timeoutMs}ms`);
  }

  // ── Build and return harness ───────────────────────────────────────────────

  const harness: FullFlowHarness = {
    workspaceRoot,
    fixtureRoot,
    project,
    initiative,
    caller,
    agentManager,
    db,
    eventBus,
    ...repos,

    waitForAgentCompletion,
    waitForAgentAttention,
    driveToCompletion,

    getEventsByType<T extends DomainEvent>(type: T['type']): T[] {
      return eventBus.getEventsByType<T>(type);
    },

    async cleanup() {
      // Kill any running agents
      const agents = await repos.agentRepository.findAll();
      await Promise.allSettled(
        agents
          .filter((a) => a.status === 'running')
          .map((a) => agentManager.stop(a.id)),
      );
      // Restore CLAUDECODE env var
      if (savedClaudeCodeEnv !== undefined) {
        process.env.CLAUDECODE = savedClaudeCodeEnv;
      }
      // Remove temp directories (fixtureBase contains fixtureRoot)
      await Promise.allSettled([
        rm(fixtureBase, { recursive: true, force: true }),
        rm(workspaceRoot, { recursive: true, force: true }),
      ]);
    },
  };

  return harness;
}