use crate::{Action, AppContext, Platform};
use util::ResultExt;

pub struct Menu<'a> {
    pub name: &'a str,
    pub items: Vec<MenuItem<'a>>,
}

pub enum MenuItem<'a> {
    Separator,
    Submenu(Menu<'a>),
    Action {
        name: &'a str,
        action: Box<dyn Action>,
        os_action: Option<OsAction>,
    },
}

impl<'a> MenuItem<'a> {
    pub fn separator() -> Self {
        Self::Separator
    }

    pub fn submenu(menu: Menu<'a>) -> Self {
        Self::Submenu(menu)
    }

    pub fn action(name: &'a str, action: impl Action) -> Self {
        Self::Action {
            name,
            action: Box::new(action),
            os_action: None,
        }
    }

    pub fn os_action(name: &'a str, action: impl Action, os_action: OsAction) -> Self {
        Self::Action {
            name,
            action: Box::new(action),
            os_action: Some(os_action),
        }
    }
}

#[derive(Copy, Clone, Eq, PartialEq)]
pub enum OsAction {
    Cut,
    Copy,
    Paste,
    SelectAll,
    Undo,
    Redo,
}

pub(crate) fn init(platform: &dyn Platform, cx: &mut AppContext) {
    platform.on_will_open_app_menu(Box::new({
        let cx = cx.to_async();
        move || {
            cx.update(|cx| cx.clear_pending_keystrokes()).ok();
        }
    }));

    platform.on_validate_app_menu_command(Box::new({
        let cx = cx.to_async();
        move |action| {
            cx.update(|cx| cx.is_action_available(action))
                .unwrap_or(false)
        }
    }));

    platform.on_app_menu_action(Box::new({
        let cx = cx.to_async();
        move |action| {
            cx.update(|cx| cx.dispatch_action(action)).log_err();
        }
    }));
}