//! The method table: which control method backs each `window.<app>` function. Target-independent,
//! so it is natively tested and usable from any build.

/// The method table one app hands the crate: the control method behind each `window.<app>`
/// function. `None` means that function is not installed; `request` is always installed.
#[derive(Clone, Copy, Debug, PartialEq, Eq)]
pub struct Methods {
    /// Behind `commands()`.
    pub commands: Option<&'static str>,
    /// Behind `execute(command, params)`, sent as `{command, params}`.
    pub execute: Option<&'static str>,
    /// Behind `docInspect(params)`.
    pub doc_inspect: Option<&'static str>,
    /// Behind `uiInspect(params)`.
    pub ui_inspect: Option<&'static str>,
    /// Behind `screenshot(params)`, sent with `data: true` unless the caller set `data`.
    pub screenshot: Option<&'static str>,
}

impl Methods {
    /// A table with no methods: only `request` is installed.
    pub const NONE: Self = Self { commands: None, execute: None, doc_inspect: None, ui_inspect: None, screenshot: None };
}

impl Default for Methods {
    /// The desktop control-server method names every Craft web build shares.
    fn default() -> Self {
        Self {
            commands: Some("engine.commands"),
            execute: Some("engine.execute"),
            doc_inspect: Some("document.inspect"),
            ui_inspect: Some("ui.inspect"),
            screenshot: Some("ui.screenshot"),
        }
    }
}

#[cfg(test)]
mod tests {
    use super::Methods;

    #[test]
    fn default_is_the_desktop_control_methods() {
        let m = Methods::default();
        assert_eq!(m.commands, Some("engine.commands"));
        assert_eq!(m.execute, Some("engine.execute"));
        assert_eq!(m.doc_inspect, Some("document.inspect"));
        assert_eq!(m.ui_inspect, Some("ui.inspect"));
        assert_eq!(m.screenshot, Some("ui.screenshot"));
    }

    #[test]
    fn none_has_no_methods() {
        let none = Methods::NONE;
        assert!([none.commands, none.execute, none.doc_inspect, none.ui_inspect, none.screenshot].iter().all(Option::is_none));
        assert_ne!(none, Methods::default());
    }
}