import pytest
import sys
import os

# Add src directory to path for imports
sys.path.insert(0, os.path.join(os.path.dirname(__file__), '..', '..', 'src'))

from utils import generate_random_string, hash_string, flatten_dict, chunk_list, DataProcessor

class TestUtils:
    
    def test_generate_random_string(self):
        # Test default length
        result = generate_random_string()
        assert len(result) == 10
        assert result.isalnum()
        
        # Test custom length
        result = generate_random_string(5)
        assert len(result) == 5
        
        # Test uniqueness
        result1 = generate_random_string(20)
        result2 = generate_random_string(20)
        assert result1 != result2
    
    def test_hash_string(self):
        # Test SHA256 (default)
        result = hash_string("hello")
        assert len(result) == 64  # SHA256 produces 64 character hex string
        
        # Test MD5
        result = hash_string("hello", "md5")
        assert len(result) == 32  # MD5 produces 32 character hex string
        
        # Test consistency
        result1 = hash_string("test")
        result2 = hash_string("test")
        assert result1 == result2
    
    def test_flatten_dict(self):
        nested = {
            "a": 1,
            "b": {
                "c": 2,
                "d": {
                    "e": 3
                }
            }
        }
        
        expected = {
            "a": 1,
            "b.c": 2,
            "b.d.e": 3
        }
        
        result = flatten_dict(nested)
        assert result == expected
        
        # Test custom separator
        result = flatten_dict(nested, sep="_")
        assert "b_c" in result
        assert "b_d_e" in result
    
    def test_chunk_list(self):
        data = [1, 2, 3, 4, 5, 6, 7, 8, 9]
        
        result = chunk_list(data, 3)
        expected = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
        assert result == expected
        
        # Test uneven chunks
        result = chunk_list(data, 4)
        expected = [[1, 2, 3, 4], [5, 6, 7, 8], [9]]
        assert result == expected
        
        # Test empty list
        result = chunk_list([], 3)
        assert result == []

class TestDataProcessor:
    
    def test_process_numbers(self):
        processor = DataProcessor()
        numbers = [1.0, 2.0, 3.0, 4.0, 5.0]
        
        result = processor.process_numbers(numbers)
        
        assert result['count'] == 5
        assert result['sum'] == 15.0
        assert result['average'] == 3.0
        assert result['min'] == 1.0
        assert result['max'] == 5.0
        assert processor.processed_count == 1
    
    def test_process_numbers_empty_list(self):
        processor = DataProcessor()
        result = processor.process_numbers([])
        assert result == {}
        assert processor.processed_count == 0