use crate::*;

/// Sections in the sequencer app that may be focused
#[derive(Copy, Clone, PartialEq, Eq)] pub enum SequencerFocus {
    /// The transport (toolbar) is focused
    Transport,
    /// The phrase list (pool) is focused
    PhrasePool,
    /// The phrase editor (sequencer) is focused
    PhraseEditor,
}

/// Focus layout of sequencer app
impl<E: Engine> FocusGrid for SequencerView<E> {
    type Item = SequencerFocus;
    fn cursor (&self) -> (usize, usize) {
        self.focus_cursor
    }
    fn cursor_mut (&mut self) -> &mut (usize, usize) {
        &mut self.focus_cursor
    }
    fn layout (&self) -> &[&[SequencerFocus]] { &[
        &[SequencerFocus::Transport],
        &[SequencerFocus::PhrasePool, SequencerFocus::PhraseEditor],
    ] }
    fn focus_enter (&mut self) {
        self.entered = true
    }
    fn focus_exit (&mut self) {
        self.entered = false
    }
    fn entered (&self) -> Option<Self::Item> {
        if self.entered { Some(self.focused()) } else { None }
    }
    fn update_focus (&mut self) {
        let focused = self.focused();
        if let Some(transport) = self.transport.as_ref() {
            transport.write().unwrap().focused = focused == SequencerFocus::Transport
        }
        self.phrases.write().unwrap().focused = focused == SequencerFocus::PhrasePool;
        self.editor.focused = focused == SequencerFocus::PhraseEditor;
    }
}