import { describe, it, expect, vi, beforeEach } from 'vitest';
import { supabase } from '../supabase';

vi.mock('../supabase', () => {
  return {
    supabase: {
      functions: {
        invoke: vi.fn(),
      },
    },
  };
});

// Mock global fetch
const mockFetch = vi.fn();
global.fetch = mockFetch;

// Import code under test after mock definition
import { invokeEdgeFunction, setUseGoGateway, setGoGatewayUrl } from '../apiAdapter';

describe('apiAdapter - Go Gateway Strangler Pattern', () => {
  beforeEach(() => {
    vi.clearAllMocks();
    setUseGoGateway('verify-receipt', false); // Reset switch
    setGoGatewayUrl('http://localhost:8080'); // Reset gateway url
  });

  it('routes to Supabase Deno Edge Function when USE_GO_GATEWAY is false', async () => {
    // 1. Mock Deno successful response
    vi.mocked(supabase.functions.invoke).mockResolvedValue({
      data: {
        success: true,
        co2Reduction: 21,
        confidence: 0.95,
      },
      error: null,
    } as any);

    // 2. Act
    const res = await invokeEdgeFunction<{ text: string }, { success: boolean; co2Reduction: number }>('verify-receipt', {
      text: 'receipt-data',
    });

    // 3. Assertions
    expect(supabase.functions.invoke).toHaveBeenCalledWith('verify-receipt', {
      body: { text: 'receipt-data' },
    });
    expect(mockFetch).not.toHaveBeenCalled();
    expect(res.success).toBe(true);
    expect(res.co2Reduction).toBe(21);
  });

  it('routes to Go Gateway via fetch when USE_GO_GATEWAY is true', async () => {
    // 1. Enable Go Gateway routing switch
    setUseGoGateway('verify-receipt', true);
    setGoGatewayUrl('https://gateway.carboany.com');

    // 2. Mock global fetch to return successful response
    mockFetch.mockResolvedValue({
      ok: true,
      json: vi.fn().mockResolvedValue({
        success: true,
        co2Reduction: 33,
        confidence: 0.88,
      }),
    } as any);

    // 3. Act
    const res = await invokeEdgeFunction<{ text: string }, { success: boolean; co2Reduction: number }>('verify-receipt', {
      text: 'receipt-data',
    });

    // 4. Assertions
    expect(supabase.functions.invoke).not.toHaveBeenCalled();
    expect(mockFetch).toHaveBeenCalledWith('https://gateway.carboany.com/api/v1/verify-receipt', expect.objectContaining({
      method: 'POST',
      body: JSON.stringify({ text: 'receipt-data' }),
    }));
    expect(res.success).toBe(true);
    expect(res.co2Reduction).toBe(33);
  });

  it('throws structured exception when response data contract is broken', async () => {
    // Enable Go Gateway routing switch
    setUseGoGateway('verify-receipt', true);

    // Mock global fetch to return broken schema (missing "co2Reduction" which is required)
    mockFetch.mockResolvedValue({
      ok: true,
      json: vi.fn().mockResolvedValue({
        success: true,
        // missing co2Reduction
        confidence: 0.99,
      }),
    } as any);

    // Act & Assert (expecting Contract Validation error)
    await expect(
      invokeEdgeFunction<{ text: string }, { success: boolean; co2Reduction: number }>('verify-receipt', {
        text: 'receipt-data',
      })
    ).rejects.toThrow(
      '[apiAdapter] API 계약 검증 실패: verify-receipt 응답에 필수 필드(co2Reduction)가 누락되었습니다.'
    );
  });
});