/**
 * Agent Router Tests
 *
 * Tests for getAgent (exitCode, taskName, initiativeName),
 * getAgentInputFiles, and getAgentPrompt procedures.
 */

import { describe, it, expect, vi, beforeEach, afterEach } from 'vitest';
import fs from 'fs/promises';
import path from 'path';
import os from 'os';
import { appRouter, createCallerFactory } from '../index.js';
import type { TRPCContext } from '../context.js';
import type { EventBus } from '../../events/types.js';

const createCaller = createCallerFactory(appRouter);

function createMockEventBus(): EventBus {
  return {
    emit: vi.fn(),
    on: vi.fn(),
    off: vi.fn(),
    once: vi.fn(),
  };
}

function createTestContext(overrides: Partial<TRPCContext> = {}): TRPCContext {
  return {
    eventBus: createMockEventBus(),
    serverStartedAt: new Date('2026-01-30T12:00:00Z'),
    processCount: 0,
    ...overrides,
  };
}

/** Minimal AgentInfo fixture matching the full interface */
function makeAgentInfo(overrides: Record<string, unknown> = {}) {
  return {
    id: 'agent-1',
    name: 'test-agent',
    taskId: null,
    initiativeId: null,
    sessionId: null,
    worktreeId: 'test-agent',
    status: 'stopped' as const,
    mode: 'execute' as const,
    provider: 'claude',
    accountId: null,
    createdAt: new Date('2026-01-01T00:00:00Z'),
    updatedAt: new Date('2026-01-01T00:00:00Z'),
    userDismissedAt: null,
    exitCode: null,
    prompt: null,
    ...overrides,
  };
}

describe('getAgent', () => {
  it('returns exitCode: 1 when agent has exitCode 1', async () => {
    const mockManager = {
      get: vi.fn().mockResolvedValue(makeAgentInfo({ exitCode: 1 })),
    };

    const ctx = createTestContext({ agentManager: mockManager as any });
    const caller = createCaller(ctx);
    const result = await caller.getAgent({ id: 'agent-1' });

    expect(result.exitCode).toBe(1);
  });

  it('returns exitCode: null when agent has no exitCode', async () => {
    const mockManager = {
      get: vi.fn().mockResolvedValue(makeAgentInfo({ exitCode: null })),
    };

    const ctx = createTestContext({ agentManager: mockManager as any });
    const caller = createCaller(ctx);
    const result = await caller.getAgent({ id: 'agent-1' });

    expect(result.exitCode).toBeNull();
  });

  it('returns taskName and initiativeName from repositories', async () => {
    const mockManager = {
      get: vi.fn().mockResolvedValue(makeAgentInfo({ taskId: 'task-1', initiativeId: 'init-1' })),
    };
    const mockTaskRepo = {
      findById: vi.fn().mockResolvedValue({ id: 'task-1', name: 'My Task' }),
    };
    const mockInitiativeRepo = {
      findById: vi.fn().mockResolvedValue({ id: 'init-1', name: 'My Initiative' }),
    };

    const ctx = createTestContext({
      agentManager: mockManager as any,
      taskRepository: mockTaskRepo as any,
      initiativeRepository: mockInitiativeRepo as any,
    });
    const caller = createCaller(ctx);
    const result = await caller.getAgent({ id: 'agent-1' });

    expect(result.taskName).toBe('My Task');
    expect(result.initiativeName).toBe('My Initiative');
  });

  it('returns taskName: null and initiativeName: null when agent has no taskId or initiativeId', async () => {
    const mockManager = {
      get: vi.fn().mockResolvedValue(makeAgentInfo({ taskId: null, initiativeId: null })),
    };

    const ctx = createTestContext({ agentManager: mockManager as any });
    const caller = createCaller(ctx);
    const result = await caller.getAgent({ id: 'agent-1' });

    expect(result.taskName).toBeNull();
    expect(result.initiativeName).toBeNull();
  });
});

describe('getAgentInputFiles', () => {
  let tmpDir: string;

  beforeEach(async () => {
    tmpDir = await fs.mkdtemp(path.join(os.tmpdir(), 'agent-test-'));
  });

  afterEach(async () => {
    await fs.rm(tmpDir, { recursive: true, force: true });
  });

  function makeAgentManagerWithWorktree(worktreeId = 'test-worktree', agentName = 'test-agent') {
    return {
      get: vi.fn().mockResolvedValue(makeAgentInfo({ worktreeId, name: agentName })),
    };
  }

  it('returns worktree_missing when worktree dir does not exist', async () => {
    const nonExistentRoot = path.join(tmpDir, 'no-such-dir');
    const mockManager = makeAgentManagerWithWorktree('test-worktree');

    const ctx = createTestContext({
      agentManager: mockManager as any,
      workspaceRoot: nonExistentRoot,
    });
    const caller = createCaller(ctx);
    const result = await caller.getAgentInputFiles({ id: 'agent-1' });

    expect(result).toEqual({ files: [], reason: 'worktree_missing' });
  });

  it('returns input_dir_missing when worktree exists but .cw/input does not', async () => {
    const worktreeId = 'test-worktree';
    const worktreeRoot = path.join(tmpDir, 'agent-workdirs', worktreeId);
    await fs.mkdir(worktreeRoot, { recursive: true });

    const mockManager = makeAgentManagerWithWorktree(worktreeId);
    const ctx = createTestContext({
      agentManager: mockManager as any,
      workspaceRoot: tmpDir,
    });
    const caller = createCaller(ctx);
    const result = await caller.getAgentInputFiles({ id: 'agent-1' });

    expect(result).toEqual({ files: [], reason: 'input_dir_missing' });
  });

  it('returns sorted file list with correct name, content, sizeBytes', async () => {
    const worktreeId = 'test-worktree';
    const inputDir = path.join(tmpDir, 'agent-workdirs', worktreeId, '.cw', 'input');
    await fs.mkdir(inputDir, { recursive: true });
    await fs.mkdir(path.join(inputDir, 'pages'), { recursive: true });

    const manifestContent = '{"files": ["a"]}';
    const fooContent = '# Foo\nHello world';
    await fs.writeFile(path.join(inputDir, 'manifest.json'), manifestContent);
    await fs.writeFile(path.join(inputDir, 'pages', 'foo.md'), fooContent);

    const mockManager = makeAgentManagerWithWorktree(worktreeId);
    const ctx = createTestContext({
      agentManager: mockManager as any,
      workspaceRoot: tmpDir,
    });
    const caller = createCaller(ctx);
    const result = await caller.getAgentInputFiles({ id: 'agent-1' });

    expect(result.reason).toBeUndefined();
    expect(result.files).toHaveLength(2);
    // Sorted alphabetically: manifest.json before pages/foo.md
    expect(result.files[0].name).toBe('manifest.json');
    expect(result.files[0].content).toBe(manifestContent);
    expect(result.files[0].sizeBytes).toBe(Buffer.byteLength(manifestContent));
    expect(result.files[1].name).toBe(path.join('pages', 'foo.md'));
    expect(result.files[1].content).toBe(fooContent);
    expect(result.files[1].sizeBytes).toBe(Buffer.byteLength(fooContent));
  });

  it('skips binary files (containing null byte)', async () => {
    const worktreeId = 'test-worktree';
    const inputDir = path.join(tmpDir, 'agent-workdirs', worktreeId, '.cw', 'input');
    await fs.mkdir(inputDir, { recursive: true });

    // Binary file with null byte
    const binaryData = Buffer.from([0x89, 0x50, 0x00, 0x4e, 0x47]);
    await fs.writeFile(path.join(inputDir, 'image.png'), binaryData);
    // Text file should still be returned
    await fs.writeFile(path.join(inputDir, 'text.txt'), 'hello');

    const mockManager = makeAgentManagerWithWorktree(worktreeId);
    const ctx = createTestContext({
      agentManager: mockManager as any,
      workspaceRoot: tmpDir,
    });
    const caller = createCaller(ctx);
    const result = await caller.getAgentInputFiles({ id: 'agent-1' });

    expect(result.files).toHaveLength(1);
    expect(result.files[0].name).toBe('text.txt');
  });

  it('truncates files larger than 500 KB and preserves original sizeBytes', async () => {
    const worktreeId = 'test-worktree';
    const inputDir = path.join(tmpDir, 'agent-workdirs', worktreeId, '.cw', 'input');
    await fs.mkdir(inputDir, { recursive: true });

    const MAX_SIZE = 500 * 1024;
    const largeContent = Buffer.alloc(MAX_SIZE + 100 * 1024, 'a'); // 600 KB
    await fs.writeFile(path.join(inputDir, 'big.txt'), largeContent);

    const mockManager = makeAgentManagerWithWorktree(worktreeId);
    const ctx = createTestContext({
      agentManager: mockManager as any,
      workspaceRoot: tmpDir,
    });
    const caller = createCaller(ctx);
    const result = await caller.getAgentInputFiles({ id: 'agent-1' });

    expect(result.files).toHaveLength(1);
    expect(result.files[0].sizeBytes).toBe(largeContent.length);
    expect(result.files[0].content).toContain('[truncated — file exceeds 500 KB]');
  });
});

describe('getAgentPrompt', () => {
  let tmpDir: string;

  beforeEach(async () => {
    tmpDir = await fs.mkdtemp(path.join(os.tmpdir(), 'agent-prompt-test-'));
  });

  afterEach(async () => {
    await fs.rm(tmpDir, { recursive: true, force: true });
  });

  it('returns prompt_not_written when PROMPT.md does not exist', async () => {
    const mockManager = {
      get: vi.fn().mockResolvedValue(makeAgentInfo({ name: 'test-agent' })),
    };

    const ctx = createTestContext({
      agentManager: mockManager as any,
      workspaceRoot: tmpDir,
    });
    const caller = createCaller(ctx);
    const result = await caller.getAgentPrompt({ id: 'agent-1' });

    expect(result).toEqual({ content: null, reason: 'prompt_not_written' });
  });

  it('returns prompt content when PROMPT.md exists', async () => {
    const agentName = 'test-agent';
    const promptDir = path.join(tmpDir, '.cw', 'agent-logs', agentName);
    await fs.mkdir(promptDir, { recursive: true });
    const promptContent = '# System\nHello';
    await fs.writeFile(path.join(promptDir, 'PROMPT.md'), promptContent);

    const mockManager = {
      get: vi.fn().mockResolvedValue(makeAgentInfo({ name: agentName, prompt: null })),
    };

    const ctx = createTestContext({
      agentManager: mockManager as any,
      workspaceRoot: tmpDir,
    });
    const caller = createCaller(ctx);
    const result = await caller.getAgentPrompt({ id: 'agent-1' });

    expect(result).toEqual({ content: promptContent });
  });

  it('returns prompt from DB when agent.prompt is set (no file needed)', async () => {
    const dbPromptContent = '# DB Prompt\nThis is persisted in the database';
    const mockManager = {
      get: vi.fn().mockResolvedValue(makeAgentInfo({ name: 'test-agent', prompt: dbPromptContent })),
    };

    // workspaceRoot has no PROMPT.md — but DB value takes precedence
    const ctx = createTestContext({
      agentManager: mockManager as any,
      workspaceRoot: tmpDir,
    });
    const caller = createCaller(ctx);
    const result = await caller.getAgentPrompt({ id: 'agent-1' });

    expect(result).toEqual({ content: dbPromptContent });
  });

  it('falls back to PROMPT.md when agent.prompt is null in DB', async () => {
    const agentName = 'test-agent';
    const promptDir = path.join(tmpDir, '.cw', 'agent-logs', agentName);
    await fs.mkdir(promptDir, { recursive: true });
    const fileContent = '# File Prompt\nThis is from the file (legacy)';
    await fs.writeFile(path.join(promptDir, 'PROMPT.md'), fileContent);

    const mockManager = {
      get: vi.fn().mockResolvedValue(makeAgentInfo({ name: agentName, prompt: null })),
    };

    const ctx = createTestContext({
      agentManager: mockManager as any,
      workspaceRoot: tmpDir,
    });
    const caller = createCaller(ctx);
    const result = await caller.getAgentPrompt({ id: 'agent-1' });

    expect(result).toEqual({ content: fileContent });
  });
});