use crate::*;

/// Different sections of the UI that may be focused.
#[derive(PartialEq, Clone, Copy)]
pub enum AppFocus {
    /// The transport is selected.
    Transport,
    /// The arranger is selected.
    Arranger,
    /// The sequencer is selected.
    Sequencer,
    /// The device chain is selected.
    Chain,
}

impl Default for AppFocus {
    fn default () -> Self { Self::Arranger }
}

impl AppFocus {
    pub fn prev (&mut self) {
        *self = match self {
            Self::Transport => Self::Chain,
            Self::Arranger  => Self::Transport,
            Self::Sequencer => Self::Arranger,
            Self::Chain     => Self::Sequencer,
        }
    }
    pub fn next (&mut self) {
        *self = match self {
            Self::Transport => Self::Arranger,
            Self::Arranger  => Self::Sequencer,
            Self::Sequencer => Self::Chain,
            Self::Chain     => Self::Transport,
        }
    }
}