/*
* Enums in rust
* largely copied from https://doc.rust-lang.org/rust-by-example/custom_types/enum.html
* ggtowell
* Nov 2023
*/

enum WebEvent {
    PageLoad,
    PageUnload,
    KeyPress(char), // an enum can have values!!
    Paste(String),
    Clunk(i32, i32), // more than one!
    Click { x: i64, y: i64 }, // it can even be an anonymous struct
}

// A function which takes a `WebEvent` enum as an argument and
// returns nothing.
fn inspect(event: WebEvent) {
    // match is smart on enum -- compiler will fail is not every one is listed
    match event {
        WebEvent::PageLoad => println!("page loaded"),
        WebEvent::PageUnload => println!("page unloaded"),
        // Destructure `c` from inside the `enum` variant.
        WebEvent::KeyPress(c) => println!("pressed '{}'.", c),
        WebEvent::Paste(s) => println!("pasted \"{}\".", s),
        // Destructure `Click` into `x` and `y`.
        WebEvent::Click { x, y } => {
            println!("clicked at x={}, y={}.", x, y);
        },
        WebEvent::Clunk(x,y) => println!("Clunk x={x} y={y}"),
    }
}

fn main() {
    let pressed = WebEvent::KeyPress('x');
    // `to_owned()` creates an owned `String` from a string slice.
    let pasted  = WebEvent::Paste(String::from("my text"));
    let click   = WebEvent::Click { x: 20, y: 80 };
    let load    = WebEvent::PageLoad;
    let unload  = WebEvent::PageUnload;
    let clunk = WebEvent::Clunk(1,2);
    inspect(pressed);
    inspect(pasted);
    inspect(click);
    inspect(load);
    inspect(unload);
    inspect(clunk);
}