// Pattern Matching — enum tags, literals, ranges, wildcard
import Std::Io::{PrintLine, PrintInt};


enum Option {
    Some(int),
    None
}

func GetValue(opt: Option) -> int {
    match opt {
        Option::Some(value) => opt.data.Some_0,
        Option::None => 0
    }
}

func Classify(n: int) -> int {
    // literal arms + exclusive range + inclusive range + wildcard
    match n {
        0 => 100,
        1 => 101,
        2..5 => 200,
        6..=10 => 300,
        _ => -1
    }
}

func ColorName(c: int) -> String {
    match c {
        1 => "red",
        2 => "green",
        3 => "blue",
        _ => "unknown"
    }
}

func Main() -> int {
    let opt1: Option = Option { tag: Option_Some };
    opt1.data.Some_0 = 42;

    let opt2: Option = Option { tag: Option_None };

    PrintLine("opt1 value: ");
    PrintInt(GetValue(opt1));
    PrintLine("");

    PrintLine("opt2 value: ");
    PrintInt(GetValue(opt2));
    PrintLine("");

    PrintLine("classify:");
    PrintInt(Classify(0));
    PrintLine("");
    PrintInt(Classify(3));
    PrintLine("");
    PrintInt(Classify(8));
    PrintLine("");
    PrintInt(Classify(99));
    PrintLine("");

    PrintLine("color:");
    PrintLine(ColorName(2));

    return 0;
}