import pytest
from dataset.problem_19.buggy import calculate_employee_bonus

def test_calculate_employee_bonus():
    employees = [
        {'id': 1, 'role': 'engineering', 'base_salary': 100000, 'rating': 4},
        {'id': 2, 'role': 'sales', 'base_salary': '80000', 'rating': 3},
        {'id': 3, 'role': 'hr', 'base_salary': 60000, 'rating': 2},
        {'id': 4, 'role': 'unknown', 'base_salary': 50000, 'rating': 5}
    ]
    
    metrics = {
        'company_multiplier': 1.2,
        'department_multipliers': {
            'engineering': 1.5,
            'sales': 1.2,
            'hr': 1.0
        }
    }
    
    # Original dicts should not be modified
    orig_employees = [dict(e) for e in employees]
    
    results = calculate_employee_bonus(employees, metrics)
    
    # Check if original was modified
    assert employees == orig_employees, "Original list was mutated"
    
    # Check results format
    assert len(results) == 4
    for r in results:
        assert 'id' in r
        assert 'bonus' in r
        assert 'role' not in r # Should only contain id and bonus
        
    # Check values
    # Emp 1: 100000 * 0.1 * 1.5 * 1.2 = 18000
    assert results[0]['bonus'] == 18000
    
    # Emp 2: 80000 * 0.05 * 1.2 * 1.2 = 5760 (string salary handling)
    assert results[1]['bonus'] == 5760
    
    # Emp 3: 0 bonus due to rating 2
    assert results[2]['bonus'] == 0
    
    # Emp 4: unknown role falls back to 1.0 multiplier
    # 50000 * 0.1 * 1.0 * 1.2 = 6000
    assert results[3]['bonus'] == 6000