import { Fraction } from '@uniswap/sdk-core';
import {
  AlgebraIntegralCustomRouter,
  calculateAmountToSwap,
  fractionAbsoluteValue,
} from '../../src/routers/algebra/algebra-integral-router';

jest.mock('../../src/routers/base/base-router', () => {
  return {
    BaseRouter: jest.fn().mockImplementation(() => ({
      getSwapAmount: jest
        .fn()
        .mockResolvedValue({ amountToSwap: 6n, zeroForOne: false }),
    })),
  };
});

const makePool = () => ({
  globalState: jest
    .fn()
    .mockResolvedValue({ price: 79228162514264337593543950336n }),
});

const makeQuoter = () => ({
  callStatic: {
    quoteExactInputSingle: jest.fn().mockResolvedValue({
      amountOut: 1n,
      sqrtPriceX96After: 2n,
    }),
  },
});

describe('Algebra integral router helpers', () => {
  it('fractionAbsoluteValue returns positive numerator and denominator', () => {
    const frac = new Fraction(-3, 4);
    const abs = fractionAbsoluteValue(frac);
    expect(abs.numerator.toString()).toBe('3');
    expect(abs.denominator.toString()).toBe('4');
  });

  it('calculateAmountToSwap handles zero and infinite ratios', () => {
    const zeroRatio = new Fraction(0, 1);
    expect(calculateAmountToSwap(zeroRatio, 1n, true, 6n, 2n)).toBe(6n);
    expect(() => calculateAmountToSwap(zeroRatio, 1n, false, 6n, 2n)).toThrow(
      'wrong parameters',
    );

    const infRatio = new Fraction(1, 0);
    expect(calculateAmountToSwap(infRatio, 1n, false, 6n, 2n)).toBe(2n);
    expect(() => calculateAmountToSwap(infRatio, 1n, true, 6n, 2n)).toThrow(
      'wrong parameters',
    );
  });
});

describe('AlgebraIntegralCustomRouter', () => {
  const positions = [{ lowerTick: -60, upperTick: 60, weight: 1 }];

  it('returns zero when already balanced', async () => {
    const pool = makePool();
    const quoter = makeQuoter();
    const logger = { info: jest.fn() } as any;
    const router = new AlgebraIntegralCustomRouter(quoter as any, logger);

    const result = await router.getSwapAmount(
      pool as any,
      positions as any,
      1n,
      1n,
      '0x1',
      '0x2',
      1,
      new Fraction(1, 1),
    );

    expect(result.amountToSwap).toBe(0n);
  });

  it('falls back to base router when legacy flow fails', async () => {
    const pool = makePool();
    pool.globalState = jest.fn().mockRejectedValue(new Error('fail'));

    const quoter = makeQuoter();
    const logger = { info: jest.fn() } as any;
    const router = new AlgebraIntegralCustomRouter(quoter as any, logger);

    const result = await router.getSwapAmount(
      pool as any,
      positions as any,
      10n,
      20n,
      '0x1',
      '0x2',
      2,
    );

    expect(result).toEqual({ amountToSwap: 6n, zeroForOne: false });
  });

  it('throws when fallback fails', async () => {
    const baseRouterModule = require('../../src/routers/base/base-router');
    baseRouterModule.BaseRouter.mockImplementationOnce(() => ({
      getSwapAmount: jest.fn().mockRejectedValue(new Error('fallback failed')),
    }));

    const pool = makePool();
    pool.globalState = jest.fn().mockRejectedValue(new Error('fail'));

    const quoter = makeQuoter();
    const logger = { info: jest.fn() } as any;
    const router = new AlgebraIntegralCustomRouter(quoter as any, logger);

    await expect(
      router.getSwapAmount(
        pool as any,
        positions as any,
        10n,
        20n,
        '0x1',
        '0x2',
        2,
      ),
    ).rejects.toThrow('fallback failed');
  });
});