use moleco::{calculate_scheme, modulo};
use num_bigint::BigUint;
use num_traits::One;

/// Main test to check if the calculate_scheme function works stable.
/// If values changed, it means the hashing algorithm changed.
#[test]
fn test_calculate_scheme() {
    let scheme = calculate_scheme("water".to_string()).unwrap();
    assert_eq!(scheme.primary.hue, 133);
    assert_eq!(scheme.first_accent.hue, 163);
    assert_eq!(scheme.second_accent.hue, 16);
    assert_eq!(scheme.complementary.hue, 312);

    let scheme2 = calculate_scheme("InChI=1S/water".to_string()).unwrap();
    assert_eq!(scheme2.primary.hue, scheme.primary.hue);
    assert_eq!(scheme2.first_accent.hue, scheme.first_accent.hue);
    assert_eq!(scheme2.second_accent.hue, scheme.second_accent.hue);
    assert_eq!(scheme2.complementary.hue, scheme.complementary.hue);

    // Test attempt to generate proper scheme with no version given
    let scheme3 = calculate_scheme("InChI=/water".to_string()).unwrap();
    assert_eq!(scheme3.primary.hue, scheme.primary.hue);
    assert_eq!(scheme3.first_accent.hue, scheme.first_accent.hue);
    assert_eq!(scheme3.second_accent.hue, scheme.second_accent.hue);
    assert_eq!(scheme3.complementary.hue, scheme.complementary.hue);
}

/// Test to check if the function errors on input with InChi= prefix but no slash.
#[test]
#[should_panic]
fn test_calculate_wrong_input_1() {
    calculate_scheme("InChI=water".to_string()).unwrap();
}

#[test]
#[should_panic]
fn test_calculate_wrong_input_2() {
    calculate_scheme("InChI=1S/".to_string()).unwrap();
}

/// Function copied from biguint docs.
fn fib(n: usize) -> BigUint {
    let mut f0 = BigUint::ZERO;
    let mut f1 = BigUint::one();
    for _ in 0..n {
        let f2 = f0 + &f1;
        f0 = f1;
        f1 = f2;
    }
    f0
}

#[test]
fn test_modulo() {
    assert_eq!(modulo(&fib(1000), 511), 119);
}