import { describe, it, expect } from 'vitest';
import { shouldUseClaudeSdk, claudeSdkBackendEnabled } from '../claude-sdk-routing.js';

/**
 * Env-flagged routing for the warm Claude-SDK backend. With CLAUDE_SDK_BACKEND off
 * (the production default) every claude task falls through to the unchanged PTY path;
 * with it on, only chat-tab claude tasks (session_id + chat_id) route to the SDK.
 */
const ON = { CLAUDE_SDK_BACKEND: '1' } as NodeJS.ProcessEnv;
const OFF = {} as NodeJS.ProcessEnv;

describe('claudeSdkBackendEnabled', () => {
  it('is false when unset or falsy', () => {
    expect(claudeSdkBackendEnabled({} as NodeJS.ProcessEnv)).toBe(false);
    expect(claudeSdkBackendEnabled({ CLAUDE_SDK_BACKEND: '' } as NodeJS.ProcessEnv)).toBe(false);
    expect(claudeSdkBackendEnabled({ CLAUDE_SDK_BACKEND: '0' } as NodeJS.ProcessEnv)).toBe(false);
    expect(claudeSdkBackendEnabled({ CLAUDE_SDK_BACKEND: 'false' } as NodeJS.ProcessEnv)).toBe(false);
    expect(claudeSdkBackendEnabled({ CLAUDE_SDK_BACKEND: 'off' } as NodeJS.ProcessEnv)).toBe(false);
    expect(claudeSdkBackendEnabled({ CLAUDE_SDK_BACKEND: 'no' } as NodeJS.ProcessEnv)).toBe(false);
  });

  it('is true for any other truthy value', () => {
    expect(claudeSdkBackendEnabled({ CLAUDE_SDK_BACKEND: '1' } as NodeJS.ProcessEnv)).toBe(true);
    expect(claudeSdkBackendEnabled({ CLAUDE_SDK_BACKEND: 'true' } as NodeJS.ProcessEnv)).toBe(true);
    expect(claudeSdkBackendEnabled({ CLAUDE_SDK_BACKEND: 'on' } as NodeJS.ProcessEnv)).toBe(true);
  });
});

describe('shouldUseClaudeSdk', () => {
  it('is always false while the env flag is off — production claude stays on PTY', () => {
    expect(shouldUseClaudeSdk({ agent: 'claude', session_id: 's1', chat_id: 'c1' }, OFF)).toBe(false);
  });

  it('routes a chat-tab claude task to the SDK when the flag is on', () => {
    expect(shouldUseClaudeSdk({ agent: 'claude', session_id: 's1', chat_id: 'c1' }, ON)).toBe(true);
  });

  it('only applies to the claude agent', () => {
    expect(shouldUseClaudeSdk({ agent: 'qwen', session_id: 's1', chat_id: 'c1' }, ON)).toBe(false);
    expect(shouldUseClaudeSdk({ agent: 'opencode', session_id: 's1', chat_id: 'c1' }, ON)).toBe(false);
    expect(shouldUseClaudeSdk({ agent: null, session_id: 's1', chat_id: 'c1' }, ON)).toBe(false);
  });

  it('requires both session_id and chat_id (session-less creators stay one-shot)', () => {
    expect(shouldUseClaudeSdk({ agent: 'claude', session_id: null, chat_id: null }, ON)).toBe(false);
    expect(shouldUseClaudeSdk({ agent: 'claude', session_id: 's1', chat_id: null }, ON)).toBe(false);
    expect(shouldUseClaudeSdk({ agent: 'claude', session_id: null, chat_id: 'c1' }, ON)).toBe(false);
  });
});