test_program.plint

fun fibonacci(n: const int): int {
    return match(n){
        0:  0,
        1:  1,
        _:  fibonacci(n - 1) + fibonacci(n - 2)
    };
}

fun fizzbuzz(n: const int): void {
    temp: int = 1;
    while(temp <= n){
        match(temp % 3, temp % 5){
            0, 0:   print("fizzbuzz\n"),
            0, _:   print("fizz\n"),
            _, 0:   print("buzz\n"),
            _, _:   print(to_str_int(temp) | "\n")
        }
        temp = temp + 1;
    }
}

fun divisible_by_3(n: const int): bool {
    return n % 3 == 0;
}

fun divisible_by_5(n: const int): bool {
    return n % 5 == 0;
}

#demonstrates how bool variables, function calls and function identifiers 
#can be used in match expressions
fun fizzbuzz2(n: const int): void {
    temp: int = 1;
    while(temp <= n){
        divisible_by_5: const bool = temp % 5 == 0;
        match(temp, temp){
            divisible_by_3(temp),   divisible_by_5: print("fizzbuzz\n"),
            divisible_by_3,         _             : print("fizz\n"),
            _,                      divisible_by_5: print("buzz\n"),
            _,                      _             : print(to_str_int(temp) | "\n")
        }
        temp = temp + 1;
    }
}
fun progressive_tax(salary: const float): float {   # not accurate
    tax_rate: float = match(salary){
        < 1000.0:   0.1,
        < 2500.0:   0.3,
        _:          0.5
    };
    return salary * tax_rate;
}

fun is_even(n: const int): bool {
    return match(n % 2){
        0:  true,
        1:  false
    };
}

fun is_even2(n: const int): bool {
    return match(n){
        is_even:    true,
        _:          false
    };
}

fun while_return_test(): void{
    number: int = 4;
    while(number > 0){
        if(number == 1){
            return;
        }
        print(to_str_int(number) | "\n");
        number = number - 1;
    }
}

fun print_file(filename: const str): void {
    handle: file = open_file(filename);
    if(bad_file(handle)){
        return;
    }
    else{
        line: str = read_line(handle);
        while(line != EOF_MARKER){
            print(line | "\n");
            line = read_line(handle);
        }
        close_file(handle);
    }
}

fun add_one(number: int): void {
    number = number + 1;
}

fun multiple_matches(): int{
    return match(1, 2, 3){
        is_even2 and is_even, is_even2, is_even2: 0,
        _, is_even2, _              : 1,
        _, _, _                     : 2
    };
}

fun main(): int{
    if(arguments_number() >= 1){
        print("Opening and printing file " | argument(0) | "\n");
        print_file(argument(0));
        print("Done!\n");
    } else {
        print("No filename provided as argument, skipping...\n");
    }

    

    # bad_variable: int = 14.33;
    # print(to_str_int(bad_variable));

    number: int = 20;
    print("Fibonacci[" | to_str_int(number) | "] number is " | to_str_int(fibonacci(number)) | ".\n");

    print("Checking if passing by reference works - printed below should be five (4 after incrementing)\n");
    do_dodania: int = 4;
    add_one(do_dodania);
    print(to_str_int(do_dodania) | "\n");
    #add_one(do_dodania + 1);                   #generuje error - dodanie do stalej (r-wartosci)
    #print(to_str_int(do_dodania) | "\n");


    print("2 + 3 * 2 = " | to_str_int(2+3*2) | " == 8?\n");

    if(number < 12 and is_even(number) or not is_even(number)){
        print("Logical precedence works!\n");
    }

    print("Tax for 1500zl = " | to_str_float(progressive_tax(1500.0)) | "\n");

    print("If multiple pattern elements and many levels of match calls work,\nthis should be a 1: " | to_str_int(multiple_matches()) | "\n");

    while_return_test(); 

    if(not is_even2(3)){
        print("ok\n");
    }
    fizzbuzz2(15);
    return 0;
}

fun inna(x: int): int{
    # inna2();
    
}

fun inna2(): int{
    return 5;
}

fun p(x: const int) : void{
    print(to_str_int(x) | "\n");
}