import { describe, it } from 'node:test';
import assert from 'node:assert/strict';
import {
  calculateSessionDurationHours,
  resolveSessionDurationHours,
  calculatePercentageShare,
  calculateHourlyShare,
  calculateExtraExpenses,
  calculateProfessorPayout,
  calculateNetProfit,
  calculatePendingReceivables,
  calculateOverpaidAmount
} from './professorShare.js';

describe('calculateSessionDurationHours', () => {
  it('computes duration between two clock times', () => {
    assert.equal(calculateSessionDurationHours('18:00', '20:00'), 2);
  });

  it('returns 0 for invalid input', () => {
    assert.equal(calculateSessionDurationHours('', ''), 0);
    assert.equal(calculateSessionDurationHours(null, undefined), 0);
  });
});

describe('resolveSessionDurationHours', () => {
  it('prefers hoursPerSection over the class time window', () => {
    assert.equal(resolveSessionDurationHours({ hoursPerSection: 2, startTime: '18:00', endTime: '20:30' }), 2);
  });

  it('falls back to the class time window', () => {
    assert.equal(resolveSessionDurationHours({ startTime: '18:00', endTime: '19:30' }), 1.5);
  });
});

describe('calculateProfessorPayout', () => {
  it('computes percentage-based payout with extra expenses', () => {
    const result = calculateProfessorPayout({
      payoutType: 'percentage',
      payoutPercentage: 40,
      revenue: 10_000_000,
      extraExpensePerSession: 100_000,
      sessionsCount: 5
    });
    assert.equal(result.baseShare, 4_000_000);
    assert.equal(result.extraExpenses, 500_000);
    assert.equal(result.totalPayout, 4_500_000);
  });

  it('computes percentage-based payout deducting serviceFeePerPerson * studentsCount first', () => {
    const result = calculateProfessorPayout({
      payoutType: 'percentage',
      payoutPercentage: 50,
      revenue: 20_000_000,
      serviceFeePerPerson: 400_000,
      studentsCount: 2
    });
    // 20M - (400k * 2) = 19.2M * 50% = 9.6M
    assert.equal(result.baseShare, 9_600_000);
    assert.equal(result.totalPayout, 9_600_000);
  });

  it('computes hourly-based payout with extra expenses', () => {
    const result = calculateProfessorPayout({
      payoutType: 'hourly',
      payoutHourlyRate: 300_000,
      sessionDurationHours: 1.5,
      extraExpensePerSession: 80_000,
      sessionsCount: 10
    });
    assert.equal(result.baseShare, 4_500_000);
    assert.equal(result.extraExpenses, 800_000);
    assert.equal(result.totalPayout, 5_300_000);
  });
});

describe('calculateNetProfit', () => {
  it('can go negative to represent a loss', () => {
    assert.equal(calculateNetProfit({ totalIncome: 1_000_000, professorTotalPayout: 4_500_000 }), -3_500_000);
  });
});

describe('calculatePendingReceivables / calculateOverpaidAmount', () => {
  it('never returns negative outstanding, and surfaces overpayments separately', () => {
    assert.equal(calculatePendingReceivables(10_000_000, 12_000_000), 0);
    assert.equal(calculateOverpaidAmount(10_000_000, 12_000_000), 2_000_000);
  });

  it('handles zero revenue classes gracefully', () => {
    assert.equal(calculatePendingReceivables(0, 0), 0);
    assert.equal(calculateExtraExpenses({}), 0);
  });
});