BEGIN {
    print "=== Functional Programming Tests ==="
}

RAWK {
    $double = (x) -> {
        return x * 2;
    };
    
    $add = (x, y) -> {
        return x + y;
    };
    
    $is_even = (x) -> {
        return x % 2 == 0;
    };
    
    $is_positive = (x) -> {
        return x > 0;
    };
    
    $square = (x) -> {
        return x * x;
    };
    
    $split_words = (text, result) -> {
        split(text, result, " ");
        return length(result);
    };
}

{
    # Create test data
    numbers[1] = 1;
    numbers[2] = 2;
    numbers[3] = 3;
    numbers[4] = 4;
    numbers[5] = 5;
    
    mixed[1] = -2;
    mixed[2] = 0;
    mixed[3] = 3;
    mixed[4] = -5;
    mixed[5] = 10;
    
    texts[1] = "hello world";
    texts[2] = "functional programming";
    texts[3] = "awk is rad";
    
    # Test map function
    doubled_count = map("double", numbers, doubled);
    expect_equal(doubled_count, 5, "map should return correct count");
    expect_equal(doubled[1], 2, "First element should be doubled");
    expect_equal(doubled[5], 10, "Last element should be doubled");
    
    # Test reduce function
    sum = reduce("add", numbers);
    expect_equal(sum, 15, "Sum of 1+2+3+4+5 should be 15");
    
    # Test filter function
    positive_count = filter("is_positive", mixed, positive_numbers);
    expect_equal(positive_count, 2, "Should find 2 positive numbers");
    expect_equal(positive_numbers[1], 3, "First positive should be 3");
    expect_equal(positive_numbers[2], 10, "Second positive should be 10");
    
    # Test find function
    first_even = find("is_even", numbers);
    expect_equal(first_even, 2, "First even number should be 2");
    
    # Test findIndex function
    first_positive_index = findIndex("is_positive", mixed);
    expect_equal(first_positive_index, 3, "First positive should be at index 3");
    
    # Test take function
    first_three_count = take(3, numbers, first_three);
    expect_equal(first_three_count, 3, "Should take 3 elements");
    expect_equal(first_three[1], 1, "First element should be 1");
    expect_equal(first_three[3], 3, "Third element should be 3");
    
    # Test drop function
    remaining_count = drop(2, numbers, remaining);
    expect_equal(remaining_count, 3, "Should drop 2 elements");
    expect_equal(remaining[1], 3, "First remaining should be 3");
    expect_equal(remaining[3], 5, "Last remaining should be 5");
    
    # Test flatMap function
    all_words_count = flatMap("split_words", texts, all_words);
    expect_equal(all_words_count, 7, "Should have 7 words total");
    
    # Test pipe function
    result = pipe(5, "square");
    expect_equal(result, 25, "5 squared should be 25");
    
    # Test pipe_multi function
    func_names[1] = "double";
    func_names[2] = "square";
    result = pipe_multi(3, func_names);
    expect_equal(result, 36, "3 doubled then squared should be 36");
    
    # Test array utilities
    key_count = keys(numbers);
    expect_equal(key_count, 5, "Should have 5 keys");
    
    value_count = values(numbers);
    expect_equal(value_count, 5, "Should have 5 values");
    
    get_keys(numbers, keys_array);
    expect_equal(keys_array[1], 1, "First key should be 1");
    expect_equal(keys_array[5], 5, "Last key should be 5");
    
    get_values(numbers, values_array);
    expect_equal(values_array[1], 1, "First value should be 1");
    expect_equal(values_array[5], 5, "Last value should be 5");
    
    print "All functional programming tests passed!";
    exit 0;
}