use crate::*;

#[derive(Clone, Copy, Debug, PartialEq)]
pub enum AppFocus<T: Copy + Debug + PartialEq> {
    /// The menu bar is focused
    Menu,
    /// The app content is focused
    Content(T)
}

pub trait FocusWrap<T> {
    fn wrap <'a, W: Widget<Engine = Tui>> (self, focus: T, content: &'a W)
        -> impl Widget<Engine = Tui> + 'a;
}

macro_rules! impl_focus {
    ($Struct:ident $Focus:ident $Grid:expr) => {
        impl HasFocus for $Struct {
            type Item = AppFocus<$Focus>;
            /// Get the currently focused item.
            fn focused (&self) -> Self::Item {
                self.focus.inner()
            }
            /// Get the currently focused item.
            fn set_focused (&mut self, to: Self::Item) {
                self.focus.set_inner(to)
            }
        }
        impl HasEnter for $Struct {
            /// Get the currently focused item.
            fn entered (&self) -> bool {
                self.focus.is_entered()
            }
            /// Get the currently focused item.
            fn set_entered (&mut self, entered: bool) {
                if entered {
                    self.focus.to_entered()
                } else {
                    self.focus.to_focused()
                }
            }
        }
        impl FocusGrid for $Struct {
            fn focus_cursor (&self) -> (usize, usize) {
                self.cursor
            }
            fn focus_cursor_mut (&mut self) -> &mut (usize, usize) {
                &mut self.cursor
            }
            fn focus_layout (&self) -> &[&[AppFocus<$Focus>]] {
                use AppFocus::*;
                use $Focus::*;
                &$Grid
            }
        }
    }
}

impl_focus!(TransportTui TransportFocus [
    //&[Menu],
    &[
        Content(PlayPause),
        Content(Bpm),
        Content(Sync),
        Content(Clock),
        Content(Quant)
    ],
]);

impl_focus!(SequencerTui SequencerFocus [
    //&[
        //Menu,
        //Menu,
        //Menu,
        //Menu,
        //Menu,
    //],
    &[
        Content(Transport(TransportFocus::PlayPause)),
        Content(Transport(TransportFocus::Bpm)),
        Content(Transport(TransportFocus::Sync)),
        Content(Transport(TransportFocus::Clock)),
        Content(Transport(TransportFocus::Quant))
    ],
    &[
        Content(Phrases),
        Content(Phrases),
        Content(PhraseEditor),
        Content(PhraseEditor),
        Content(PhraseEditor),
    ],
]);

impl_focus!(ArrangerTui  ArrangerFocus [
    //&[
        //Menu,
        //Menu,
        //Menu,
        //Menu,
        //Menu,
    //],
    &[
        Content(Transport(TransportFocus::PlayPause)),
        Content(Transport(TransportFocus::Bpm)),
        Content(Transport(TransportFocus::Sync)),
        Content(Transport(TransportFocus::Clock)),
        Content(Transport(TransportFocus::Quant))
    ], &[
        Content(Arranger),
        Content(Arranger),
        Content(Arranger),
        Content(Arranger),
        Content(Arranger),
    ], &[
        Content(Phrases),
        Content(Phrases),
        Content(PhraseEditor),
        Content(PhraseEditor),
        Content(PhraseEditor),
    ],
]);