/**
 * Unit tests for subscription slippage routes
 * Focus: PUT /:id/slippage endpoint validation logic
 *
 * Note: These are logic tests, not full integration tests with database
 */

describe('Subscription Slippage Routes', () => {
  describe('normalizePercent validation', () => {
    const normalizePercent = (value: any) => {
      const normalized = typeof value === 'string' ? Number(value) : value;
      if (!Number.isFinite(normalized) || normalized < 0) {
        return null;
      }
      return normalized;
    };

    it('should accept valid positive number', () => {
      expect(normalizePercent(0.5)).toBe(0.5);
      expect(normalizePercent(1)).toBe(1);
      expect(normalizePercent(5)).toBe(5);
      expect(normalizePercent(100)).toBe(100);
    });

    it('should accept zero', () => {
      expect(normalizePercent(0)).toBe(0);
    });

    it('should accept string numbers', () => {
      expect(normalizePercent('0.5')).toBe(0.5);
      expect(normalizePercent('1')).toBe(1);
      expect(normalizePercent('0')).toBe(0);
    });

    it('should reject negative numbers', () => {
      expect(normalizePercent(-1)).toBeNull();
      expect(normalizePercent(-0.5)).toBeNull();
      expect(normalizePercent('-1')).toBeNull();
    });

    it('should reject invalid values', () => {
      expect(normalizePercent(NaN)).toBeNull();
      expect(normalizePercent(Infinity)).toBeNull();
      expect(normalizePercent(-Infinity)).toBeNull();
      expect(normalizePercent('abc')).toBeNull();
      expect(normalizePercent(null)).toBeNull();
      expect(normalizePercent(undefined)).toBeNull();
    });
  });

  describe('calcMinRateFromPercent', () => {
    const calcMinRateFromPercent = (percent: number, currentRate: string): string => {
      const rateNum = Number(currentRate);
      if (!Number.isFinite(rateNum) || rateNum <= 0) {
        return '0';
      }
      // min_acceptable_rate = current_rate / (1 + percent/100)
      const minRate = rateNum / (1 + percent / 100);
      return minRate.toFixed(8);
    };

    it('should calculate min rate correctly with 0.5% slippage', () => {
      // If current rate is 100 and slippage is 0.5%, min rate = 100 / 1.005 = 99.502...
      const result = calcMinRateFromPercent(0.5, '100');
      expect(Number(result)).toBeCloseTo(99.5024876, 5);
    });

    it('should calculate min rate correctly with 1% slippage', () => {
      // If current rate is 100 and slippage is 1%, min rate = 100 / 1.01 = 99.0099...
      const result = calcMinRateFromPercent(1, '100');
      expect(Number(result)).toBeCloseTo(99.00990099, 5);
    });

    it('should calculate min rate correctly with 5% slippage', () => {
      // If current rate is 100 and slippage is 5%, min rate = 100 / 1.05 = 95.238...
      const result = calcMinRateFromPercent(5, '100');
      expect(Number(result)).toBeCloseTo(95.23809524, 5);
    });

    it('should handle zero percent (no slippage)', () => {
      // If slippage is 0%, min rate equals current rate
      const result = calcMinRateFromPercent(0, '100');
      expect(Number(result)).toBe(100);
    });

    it('should return 0 for invalid rate', () => {
      expect(calcMinRateFromPercent(0.5, '0')).toBe('0');
      expect(calcMinRateFromPercent(0.5, '-100')).toBe('0');
      expect(calcMinRateFromPercent(0.5, 'abc')).toBe('0');
    });
  });

  describe('slippage config validation', () => {
    describe('percent mode', () => {
      it('should accept valid percent config', () => {
        const rawConfig = {
          mode: 'percent',
          percent: 0.5,
          base_currency: 'USD',
        };

        expect(rawConfig.mode).toBe('percent');
        expect(rawConfig.percent).toBe(0.5);
        expect(rawConfig.base_currency).toBe('USD');
      });

      it('should reject config with negative percent', () => {
        const rawConfig = {
          mode: 'percent',
          percent: -1,
        };

        const normalizePercent = (value: any) => {
          const normalized = typeof value === 'string' ? Number(value) : value;
          if (!Number.isFinite(normalized) || normalized < 0) {
            return null;
          }
          return normalized;
        };

        expect(normalizePercent(rawConfig.percent)).toBeNull();
      });

      it('should accept config with pre-calculated min_acceptable_rate', () => {
        const rawConfig = {
          mode: 'percent',
          percent: 0.5,
          min_acceptable_rate: '99.5024876',
          base_currency: 'USD',
        };

        expect(rawConfig.min_acceptable_rate).toBe('99.5024876');
      });
    });

    describe('rate mode', () => {
      it('should require min_acceptable_rate for rate mode', () => {
        const rawConfig: { mode: string; percent: number; min_acceptable_rate?: string } = {
          mode: 'rate',
          percent: 0,
          // missing min_acceptable_rate
        };

        const minRate = rawConfig.min_acceptable_rate ?? (rawConfig as any).minAcceptableRate;
        expect(minRate === undefined || minRate === null || minRate === '').toBe(true);
      });

      it('should accept valid rate config', () => {
        const rawConfig = {
          mode: 'rate',
          percent: 0.5,
          min_acceptable_rate: '95.5',
          base_currency: 'USD',
        };

        expect(rawConfig.mode).toBe('rate');
        expect(rawConfig.min_acceptable_rate).toBe('95.5');
      });
    });

    describe('legacy slippage_percent support', () => {
      it('should accept simple slippage_percent', () => {
        const reqBody = {
          slippage_percent: 0.5,
        };

        const normalizePercent = (value: any) => {
          const normalized = typeof value === 'string' ? Number(value) : value;
          if (!Number.isFinite(normalized) || normalized < 0) {
            return null;
          }
          return normalized;
        };

        expect(normalizePercent(reqBody.slippage_percent)).toBe(0.5);
      });

      it('should reject invalid slippage_percent', () => {
        const reqBody = {
          slippage_percent: 'invalid',
        };

        const normalizePercent = (value: any) => {
          const normalized = typeof value === 'string' ? Number(value) : value;
          if (!Number.isFinite(normalized) || normalized < 0) {
            return null;
          }
          return normalized;
        };

        expect(normalizePercent(reqBody.slippage_percent)).toBeNull();
      });
    });
  });

  describe('config building', () => {
    it('should build percent mode config with timestamp', () => {
      const now = Date.now();
      const config = {
        mode: 'percent',
        percent: 0.5,
        base_currency: 'USD',
        min_acceptable_rate: '99.5',
        updated_at_ms: now,
      };

      expect(config.mode).toBe('percent');
      expect(config.percent).toBe(0.5);
      expect(config.updated_at_ms).toBe(now);
    });

    it('should build rate mode config with all fields', () => {
      const now = Date.now();
      const config = {
        mode: 'rate',
        percent: 0,
        min_acceptable_rate: '95.0',
        base_currency: 'USD',
        rate_at_config_time: '100.0',
        updated_at_ms: now,
      };

      expect(config.mode).toBe('rate');
      expect(config.min_acceptable_rate).toBe('95.0');
      expect(config.rate_at_config_time).toBe('100.0');
    });
  });

  describe('error scenarios', () => {
    it('should return error when no config provided', () => {
      const rawConfig = null;
      const slippagePercent = undefined;

      const hasConfig = rawConfig && typeof rawConfig === 'object';
      const hasPercent = slippagePercent !== undefined && slippagePercent !== null;

      expect(hasConfig || hasPercent).toBe(false);
      // In actual endpoint: return 400 with error 'slippage config is required'
    });

    it('should return error for rate mode without min_acceptable_rate', () => {
      const rawConfig: { mode: string; percent: number; min_acceptable_rate?: string } = {
        mode: 'rate',
        percent: 0,
      };

      const minRate = rawConfig.min_acceptable_rate ?? (rawConfig as any).minAcceptableRate;
      const isInvalid = minRate === undefined || minRate === null || minRate === '';

      expect(isInvalid).toBe(true);
      // In actual endpoint: return 400 with error 'min_acceptable_rate is required for rate mode'
    });
  });
});
