oh-my-opencode-slim/src/multiplexer/session-manager.test.ts

import { beforeEach, describe, expect, mock, test } from 'bun:test';
import { MultiplexerSessionManager } from './session-manager';

// Define the mock multiplexer
const mockMultiplexer = {
  type: 'tmux' as const,
  isAvailable: mock(async () => true),
  isInsideSession: mock(() => true),
  spawnPane: mock(async () => ({
    success: true,
    paneId: '%mock-pane',
  })),
  closePane: mock(async () => true),
  applyLayout: mock(async () => {}),
};

// Mock the multiplexer module
mock.module('../multiplexer', () => ({
  getMultiplexer: () => mockMultiplexer,
  isServerRunning: mock(async () => true),
  startAvailabilityCheck: () => {},
}));

// Mock the plugin context
function createMockContext(overrides?: {
  sessionStatusResult?: { data?: Record<string, { type: string }> };
  directory?: string;
}) {
  const defaultPort = process.env.OPENCODE_PORT ?? '4096';
  return {
    client: {
      session: {
        status: mock(
          async () => overrides?.sessionStatusResult ?? { data: {} },
        ),
      },
    },
    directory: overrides?.directory ?? '/test/directory',
    serverUrl: new URL(`http://localhost:${defaultPort}`),
  } as any;
}

const defaultMultiplexerConfig = {
  type: 'tmux' as const,
  layout: 'main-vertical' as const,
  main_pane_size: 60,
};

function createDeferred<T>() {
  let resolve!: (value: T) => void;
  let reject!: (reason?: unknown) => void;
  const promise = new Promise<T>((res, rej) => {
    resolve = res;
    reject = rej;
  });
  return { promise, resolve, reject };
}

describe('MultiplexerSessionManager', () => {
  beforeEach(() => {
    mockMultiplexer.spawnPane.mockReset();
    mockMultiplexer.spawnPane.mockResolvedValue({
      success: true,
      paneId: '%mock-pane',
    });
    mockMultiplexer.closePane.mockReset();
    mockMultiplexer.closePane.mockResolvedValue(true);
    mockMultiplexer.isInsideSession.mockReset();
    mockMultiplexer.isInsideSession.mockReturnValue(true);
  });

  describe('constructor', () => {
    test('initializes with config', () => {
      const ctx = createMockContext();
      const manager = new MultiplexerSessionManager(
        ctx,
        defaultMultiplexerConfig,
      );
      expect(manager).toBeDefined();
    });
  });

  describe('onSessionCreated', () => {
    test('spawns pane for child sessions', async () => {
      const ctx = createMockContext();
      const manager = new MultiplexerSessionManager(
        ctx,
        defaultMultiplexerConfig,
      );

      await manager.onSessionCreated({
        type: 'session.created',
        properties: {
          info: {
            id: 'child-123',
            parentID: 'parent-456',
            title: 'Test Worker',
          },
        },
      });

      expect(mockMultiplexer.spawnPane).toHaveBeenCalled();
      expect(mockMultiplexer.spawnPane).toHaveBeenCalledWith(
        'child-123',
        'Test Worker',
        `http://localhost:${process.env.OPENCODE_PORT ?? '4096'}/`,
        '/test/directory',
      );
    });

    test('ignores sessions without parentID', async () => {
      const ctx = createMockContext();
      const manager = new MultiplexerSessionManager(
        ctx,
        defaultMultiplexerConfig,
      );

      await manager.onSessionCreated({
        type: 'session.created',
        properties: {
          info: {
            id: 'root-session',
            title: 'Main Chat',
          },
        },
      });

      expect(mockMultiplexer.spawnPane).not.toHaveBeenCalled();
    });

    test('prefers child session directory when present', async () => {
      const ctx = createMockContext({ directory: '/parent/directory' });
      const manager = new MultiplexerSessionManager(
        ctx,
        defaultMultiplexerConfig,
      );

      await manager.onSessionCreated({
        type: 'session.created',
        properties: {
          info: {
            id: 'child-456',
            parentID: 'parent-456',
            title: 'Nested Worker',
            directory: '/child/directory',
          },
        },
      });

      expect(mockMultiplexer.spawnPane).toHaveBeenCalledWith(
        'child-456',
        'Nested Worker',
        `http://localhost:${process.env.OPENCODE_PORT ?? '4096'}/`,
        '/child/directory',
      );
    });

    test('ignores if disabled in config', async () => {
      const ctx = createMockContext();
      const manager = new MultiplexerSessionManager(ctx, {
        ...defaultMultiplexerConfig,
        type: 'none',
      });

      await manager.onSessionCreated({
        type: 'session.created',
        properties: {
          info: { id: 'child', parentID: 'parent' },
        },
      });

      expect(mockMultiplexer.spawnPane).not.toHaveBeenCalled();
    });

    test('does not spawn twice for duplicate create events while spawning', async () => {
      const ctx = createMockContext();
      const manager = new MultiplexerSessionManager(
        ctx,
        defaultMultiplexerConfig,
      );
      const deferred = createDeferred<{ success: true; paneId: string }>();

      mockMultiplexer.spawnPane.mockImplementationOnce(() => deferred.promise);

      const event = {
        type: 'session.created',
        properties: {
          info: {
            id: 'child-race',
            parentID: 'parent-race',
            title: 'Race Worker',
          },
        },
      };

      const firstCreate = manager.onSessionCreated(event);
      const secondCreate = manager.onSessionCreated(event);

      await Promise.resolve();

      expect(mockMultiplexer.spawnPane).toHaveBeenCalledTimes(1);

      deferred.resolve({ success: true, paneId: 'p-race' });

      await Promise.all([firstCreate, secondCreate]);

      expect(mockMultiplexer.spawnPane).toHaveBeenCalledTimes(1);
    });
  });

  describe('polling and closure', () => {
    test('closes pane when session becomes idle', async () => {
      const ctx = createMockContext();
      mockMultiplexer.spawnPane.mockResolvedValue({
        success: true,
        paneId: 'p-1',
      });

      const manager = new MultiplexerSessionManager(
        ctx,
        defaultMultiplexerConfig,
      );

      // Register session
      await manager.onSessionCreated({
        type: 'session.created',
        properties: { info: { id: 'c1', parentID: 'p1' } },
      });

      // Mock status
      ctx.client.session.status.mockResolvedValue({
        data: { c1: { type: 'idle' } },
      });

      await (manager as any).pollSessions();

      expect(mockMultiplexer.closePane).toHaveBeenCalledWith('p-1');
    });

    test('does not close on transient status absence', async () => {
      const ctx = createMockContext();
      const manager = new MultiplexerSessionManager(
        ctx,
        defaultMultiplexerConfig,
      );

      await manager.onSessionCreated({
        type: 'session.created',
        properties: { info: { id: 'c1', parentID: 'p1' } },
      });

      ctx.client.session.status.mockResolvedValue({ data: {} });
      await (manager as any).pollSessions();

      expect(mockMultiplexer.closePane).not.toHaveBeenCalled();
    });

    test('respawns pane on busy for known prior session', async () => {
      const ctx = createMockContext();
      const manager = new MultiplexerSessionManager(
        ctx,
        defaultMultiplexerConfig,
      );

      mockMultiplexer.spawnPane
        .mockResolvedValueOnce({
          success: true,
          paneId: 'p-1',
        })
        .mockResolvedValueOnce({
          success: true,
          paneId: 'p-2',
        });

      await manager.onSessionCreated({
        type: 'session.created',
        properties: {
          info: {
            id: 'child-789',
            parentID: 'parent-789',
            title: 'Worker',
            directory: '/task/dir',
          },
        },
      });

      ctx.client.session.status.mockResolvedValue({
        data: { 'child-789': { type: 'idle' } },
      });
      await (manager as any).pollSessions();

      await manager.onSessionStatus({
        type: 'session.status',
        properties: {
          sessionID: 'child-789',
          status: { type: 'busy' },
        },
      });

      expect(mockMultiplexer.spawnPane).toHaveBeenCalledTimes(2);
      expect(mockMultiplexer.spawnPane).toHaveBeenCalledWith(
        'child-789',
        'Worker',
        `http://localhost:${process.env.OPENCODE_PORT ?? '4096'}/`,
        '/task/dir',
      );
      expect(mockMultiplexer.closePane).toHaveBeenCalledWith('p-1');
      expect(mockMultiplexer.closePane).toHaveBeenCalledTimes(1);
    });

    test('does nothing on busy for unknown session', async () => {
      const ctx = createMockContext();
      const manager = new MultiplexerSessionManager(
        ctx,
        defaultMultiplexerConfig,
      );

      await manager.onSessionStatus({
        type: 'session.status',
        properties: {
          sessionID: 'unknown-session',
          status: { type: 'busy' },
        },
      });

      expect(mockMultiplexer.spawnPane).not.toHaveBeenCalled();
    });

    test('re-checks tracked sessions after async respawn guard', async () => {
      const ctx = createMockContext();
      const manager = new MultiplexerSessionManager(
        ctx,
        defaultMultiplexerConfig,
      );

      mockMultiplexer.spawnPane
        .mockResolvedValueOnce({ success: true, paneId: 'p-1' })
        .mockResolvedValueOnce({
          success: true,
          paneId: 'p-should-not-happen',
        });

      await manager.onSessionCreated({
        type: 'session.created',
        properties: {
          info: {
            id: 'child-999',
            parentID: 'parent-999',
            title: 'Worker',
            directory: '/task/dir',
          },
        },
      });

      ctx.client.session.status.mockResolvedValue({
        data: { 'child-999': { type: 'idle' } },
      });
      await (manager as any).pollSessions();

      const respawnPromise = (manager as any).respawnIfKnown('child-999');

      (manager as any).sessions.set('child-999', {
        sessionId: 'child-999',
        paneId: 'p-existing',
        parentId: 'parent-999',
        title: 'Worker',
        directory: '/task/dir',
        createdAt: Date.now(),
        lastSeenAt: Date.now(),
      });

      await respawnPromise;

      expect(mockMultiplexer.spawnPane).toHaveBeenCalledTimes(1);
      expect((manager as any).sessions.get('child-999')?.paneId).toBe(
        'p-existing',
      );
    });

    test('does not respawn while initial pane spawn is still in progress', async () => {
      const ctx = createMockContext();
      const manager = new MultiplexerSessionManager(
        ctx,
        defaultMultiplexerConfig,
      );
      const deferred = createDeferred<{ success: true; paneId: string }>();

      mockMultiplexer.spawnPane.mockImplementationOnce(() => deferred.promise);

      const createPromise = manager.onSessionCreated({
        type: 'session.created',
        properties: {
          info: {
            id: 'child-busy-race',
            parentID: 'parent-busy-race',
            title: 'Busy Worker',
            directory: '/task/dir',
          },
        },
      });

      await manager.onSessionStatus({
        type: 'session.status',
        properties: {
          sessionID: 'child-busy-race',
          status: { type: 'busy' },
        },
      });

      expect(mockMultiplexer.spawnPane).toHaveBeenCalledTimes(1);

      deferred.resolve({ success: true, paneId: 'p-busy-race' });

      await createPromise;

      expect(mockMultiplexer.spawnPane).toHaveBeenCalledTimes(1);
    });
  });

  describe('cleanup', () => {
    test('closes all tracked panes concurrently', async () => {
      const ctx = createMockContext();
      mockMultiplexer.spawnPane
        .mockResolvedValueOnce({ success: true, paneId: 'p1' })
        .mockResolvedValueOnce({ success: true, paneId: 'p2' });

      const manager = new MultiplexerSessionManager(
        ctx,
        defaultMultiplexerConfig,
      );

      await manager.onSessionCreated({
        type: 'session.created',
        properties: { info: { id: 's1', parentID: 'p1' } },
      });
      await manager.onSessionCreated({
        type: 'session.created',
        properties: { info: { id: 's2', parentID: 'p2' } },
      });

      await manager.cleanup();

      expect(mockMultiplexer.closePane).toHaveBeenCalledTimes(2);
      expect(mockMultiplexer.closePane).toHaveBeenCalledWith('p1');
      expect(mockMultiplexer.closePane).toHaveBeenCalledWith('p2');
    });
  });
});

// Backward compatibility test
describe('TmuxSessionManager (backward compatibility)', () => {
  test('TmuxSessionManager is alias for MultiplexerSessionManager', async () => {
    const { TmuxSessionManager } = await import('./session-manager');
    expect(TmuxSessionManager).toBe(MultiplexerSessionManager);
  });
});