use crate::*;
/// MIDI message structural
pub type PhraseData   = Vec<Vec<MidiMessage>>;
/// MIDI message serialized
pub type PhraseMessage = Vec<u8>;
/// Collection of serialized MIDI messages
pub type PhraseChunk   = [Vec<PhraseMessage>];
/// Root level object for standalone `tek_sequencer`
pub struct Sequencer<E: Engine> {
    /// Which view is focused
    pub focus_cursor: (usize, usize),
    /// Controls the JACK transport.
    pub transport:    Option<Arc<RwLock<TransportToolbar<E>>>>,
    /// Pool of all phrases available to the sequencer
    pub phrases:      Arc<RwLock<PhrasePool<E>>>,
    /// Phrase editor view
    pub editor:       PhraseEditor<E>,
}
/// 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,
}
/// Status bar for sequencer app
pub enum SequencerStatusBar {
    Transport,
    PhrasePool,
    PhraseEditor,
}
/// Contains all phrases in a project
pub struct PhrasePool<E: Engine> {
    _engine:     PhantomData<E>,
    /// Scroll offset
    pub scroll:  usize,
    /// Highlighted phrase
    pub phrase:  usize,
    /// Phrases in the pool
    pub phrases: Vec<Arc<RwLock<Phrase>>>,
    /// Whether this widget is focused
    pub focused: bool,
    /// Mode switch
    pub mode:    Option<PhrasePoolMode>,
}
/// Modes for phrase pool
pub enum PhrasePoolMode {
    /// Renaming a pattern
    Rename(usize, String),
    /// Editing the length of a pattern
    Length(usize, usize, PhraseLengthFocus),
}
/// A MIDI sequence.
#[derive(Debug, Clone)]
pub struct Phrase {
    pub uuid:        uuid::Uuid,
    /// Name of phrase
    pub name:        String,
    /// Temporal resolution in pulses per quarter note
    pub ppq:         usize,
    /// Length of phrase in pulses
    pub length:      usize,
    /// Notes in phrase
    pub notes:       PhraseData,
    /// Whether to loop the phrase or play it once
    pub loop_on:     bool,
    /// Start of loop
    pub loop_start:  usize,
    /// Length of loop
    pub loop_length: usize,
    /// All notes are displayed with minimum length
    pub percussive:  bool,
    /// Identifying color of phrase
    pub color:       Color,
}
/// Contains state for viewing and editing a phrase
pub struct PhraseEditor<E: Engine> {
    _engine:       PhantomData<E>,
    /// Phrase being played
    pub phrase:    Option<Arc<RwLock<Phrase>>>,
    /// Length of note that will be inserted, in pulses
    pub note_len:  usize,
    /// The full piano keys are rendered to this buffer
    pub keys:      Buffer,
    /// The full piano roll is rendered to this buffer
    pub buffer:    BigBuffer,
    /// Cursor/scroll/zoom in pitch axis
    pub note_axis: FixedAxis<usize>,
    /// Cursor/scroll/zoom in time axis
    pub time_axis: ScaledAxis<usize>,
    /// Whether this widget is focused
    pub focused:   bool,
    /// Whether note enter mode is enabled
    pub entered:   bool,
    /// Display mode
    pub mode:      bool,
    /// Notes currently held at input
    pub notes_in:  Arc<RwLock<[bool; 128]>>,
    /// Notes currently held at output
    pub notes_out: Arc<RwLock<[bool; 128]>>,
}
/// Phrase player.
pub struct PhrasePlayer<E: Engine> {
    _engine:            PhantomData<E>,
    /// Phrase being played
    pub phrase:         Option<Arc<RwLock<Phrase>>>,
    /// Notes currently held at input
    pub notes_in:       Arc<RwLock<[bool; 128]>>,
    /// Notes currently held at output
    pub notes_out:      Arc<RwLock<[bool; 128]>>,
    /// Current point in playing phrase
    pub now:            usize,
    /// Play input through output.
    pub monitoring:     bool,
    /// Write input to sequence.
    pub recording:      bool,
    /// Overdub input to sequence.
    pub overdub:        bool,
    /// Output from current sequence.
    pub midi_out:       Option<Port<MidiOut>>,
    /// MIDI output buffer
    pub midi_out_buf:   Vec<Vec<Vec<u8>>>,
    /// Send all notes off
    pub reset:          bool, // TODO?: after Some(nframes)
}
/// Focus layout of sequencer app
impl<E: Engine> FocusGrid<SequencerFocus> for Sequencer<E> {
    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 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;
    }
}
impl<E: Engine> PhrasePool<E> {
    pub fn new () -> Self {
        Self {
            _engine: Default::default(),
            scroll:  0,
            phrase:  0,
            phrases: vec![Arc::new(RwLock::new(Phrase::default()))],
            focused: false,
            mode:    None,
        }
    }
    pub fn phrase (&self) -> &Arc<RwLock<Phrase>> {
        &self.phrases[self.phrase]
    }
    pub fn index_of (&self, phrase: &Phrase) -> Option<usize> {
        for i in 0..self.phrases.len() {
            if *self.phrases[i].read().unwrap() == *phrase {
                return Some(i)
            }
        }
        return None
    }
    pub fn len (&self) -> usize {
        self.phrases.len()
    }
    pub fn index_before (&self, index: usize) -> usize {
        index.overflowing_sub(1).0.min(self.len() - 1)
    }
    pub fn index_after (&self, index: usize) -> usize {
        (index + 1) % self.len()
    }
    pub fn select_prev (&mut self) {
        self.phrase = self.index_before(self.phrase)
    }
    pub fn select_next (&mut self) {
        self.phrase = self.index_after(self.phrase)
    }
    pub fn append_new (&mut self, name: Option<&str>, color: Option<Color>) {
        let mut phrase = Phrase::default();
        phrase.name   = String::from(name.unwrap_or("(new)"));
        phrase.color  = color.unwrap_or_else(random_color);
        phrase.length = 4 * PPQ;
        phrase.notes  = vec![Vec::with_capacity(16);phrase.length];
        self.phrases.push(Arc::new(RwLock::new(phrase)));
        self.phrase = self.phrases.len() - 1;
    }
    pub fn insert_new (&mut self, name: Option<&str>, color: Option<Color>) {
        let mut phrase = Phrase::default();
        phrase.name   = String::from(name.unwrap_or("(new)"));
        phrase.color  = color.unwrap_or_else(random_color);
        phrase.length = 4 * PPQ;
        phrase.notes  = vec![Vec::with_capacity(16);phrase.length];
        self.phrases.insert(self.phrase + 1, Arc::new(RwLock::new(phrase)));
        self.phrase += 1;
    }
    pub fn insert_dup (&mut self) {
        let mut phrase = self.phrases[self.phrase].read().unwrap().duplicate();
        phrase.color = random_color_near(phrase.color, 0.2);
        self.phrases.insert(self.phrase + 1, Arc::new(RwLock::new(phrase)));
        self.phrase += 1;
    }
    pub fn randomize_color (&mut self) {
        let mut phrase = self.phrases[self.phrase].write().unwrap();
        phrase.color = random_color();
    }
    pub fn begin_rename (&mut self) {
        self.mode = Some(PhrasePoolMode::Rename(
            self.phrase,
            self.phrases[self.phrase].read().unwrap().name.clone()
        ));
    }
    pub fn begin_length (&mut self) {
        self.mode = Some(PhrasePoolMode::Length(
            self.phrase,
            self.phrases[self.phrase].read().unwrap().length,
            PhraseLengthFocus::Bar
        ));
    }
    pub fn move_up (&mut self) {
        if self.phrase > 1 {
            self.phrases.swap(self.phrase - 1, self.phrase);
            self.phrase -= 1;
        }
    }
    pub fn move_down (&mut self) {
        if self.phrase < self.phrases.len().saturating_sub(1) {
            self.phrases.swap(self.phrase + 1, self.phrase);
            self.phrase += 1;
        }
    }
}
impl<E: Engine> PhraseEditor<E> {
    pub fn new () -> Self {
        Self {
            _engine:   Default::default(),
            phrase:    None,
            note_len:  24,
            notes_in:  Arc::new(RwLock::new([false;128])),
            notes_out: Arc::new(RwLock::new([false;128])),
            keys:      keys_vert(),
            buffer:    Default::default(),
            note_axis: FixedAxis { start: 12, point: Some(36) },
            time_axis: ScaledAxis { start: 0, scale: 24, point: Some(0) },
            focused:   false,
            entered:   false,
            mode:      false,
        }
    }
}
impl Phrase {
    pub fn new (
        name:    impl AsRef<str>,
        loop_on: bool,
        length:  usize,
        notes:   Option<PhraseData>,
        color:   Option<Color>,
    ) -> Self {
        Self {
            uuid:        uuid::Uuid::new_v4(),
            name:        name.as_ref().to_string(),
            ppq:         PPQ,
            length,
            notes:       notes.unwrap_or(vec![Vec::with_capacity(16);length]),
            loop_on,
            loop_start:  0,
            loop_length: length,
            percussive:  true,
            color:       color.unwrap_or_else(random_color)
        }
    }
    pub fn duplicate (&self) -> Self {
        let mut clone = self.clone();
        clone.uuid = uuid::Uuid::new_v4();
        clone
    }
    pub fn toggle_loop (&mut self) {
        self.loop_on = !self.loop_on;
    }
    pub fn record_event (&mut self, pulse: usize, message: MidiMessage) {
        if pulse >= self.length {
            panic!("extend phrase first")
        }
        self.notes[pulse].push(message);
    }
    /// Check if a range `start..end` contains MIDI Note On `k`
    pub fn contains_note_on (&self, k: u7, start: usize, end: usize) -> bool {
        //panic!("{:?} {start} {end}", &self);
        for events in self.notes[start.max(0)..end.min(self.notes.len())].iter() {
            for event in events.iter() {
                match event {
                    MidiMessage::NoteOn {key,..} => {
                        if *key == k {
                            return true
                        }
                    }
                    _ => {}
                }
            }
        }
        return false
    }
}
impl Default for Phrase {
    fn default () -> Self { Self::new("(empty)", false, 0, None, Some(Color::Rgb(0, 0, 0))) }
}
impl std::cmp::PartialEq for Phrase {
    fn eq (&self, other: &Self) -> bool {
        self.uuid == other.uuid
    }
}
impl Eq for Phrase {}
impl<E: Engine> PhrasePlayer<E> {
    pub fn new () -> Self {
        Self {
            _engine:      Default::default(),
            phrase:       None,
            notes_in:     Arc::new(RwLock::new([false;128])),
            notes_out:    Arc::new(RwLock::new([false;128])),
            monitoring:   false,
            recording:    false,
            overdub:      true,
            midi_out:     None,
            midi_out_buf: vec![Vec::with_capacity(16);16384],
            reset:        true,
            now:          0,
        }
    }
    pub fn toggle_monitor (&mut self) {
        self.monitoring = !self.monitoring;
    }
    pub fn toggle_record (&mut self) {
        self.recording = !self.recording;
    }
    pub fn toggle_overdub (&mut self) {
        self.overdub = !self.overdub;
    }
}
/// Displays and edits phrase length
pub struct PhraseLength<E: Engine> {
    _engine: PhantomData<E>,
    /// Pulses per beat (quaver)
    pub ppq:    usize,
    /// Beats per bar
    pub bpb:    usize,
    /// Length of phrase in pulses
    pub pulses: usize,
    /// Selected subdivision
    pub focus:  Option<PhraseLengthFocus>,
}
impl<E: Engine> PhraseLength<E> {
    pub fn new (pulses: usize, focus: Option<PhraseLengthFocus>) -> Self {
        Self {
            _engine: Default::default(),
            ppq: PPQ,
            bpb: 4,
            pulses,
            focus
        }
    }
    pub fn bars (&self) -> usize {
        self.pulses / (self.bpb * self.ppq)
    }
    pub fn beats (&self) -> usize {
        (self.pulses % (self.bpb * self.ppq)) / self.ppq
    }
    pub fn ticks (&self) -> usize {
        self.pulses % self.ppq
    }
    pub fn bars_string (&self) -> String {
        format!("{}", self.bars())
    }
    pub fn beats_string (&self) -> String {
        format!("{}", self.beats())
    }
    pub fn ticks_string (&self) -> String {
        format!("{:>02}", self.ticks())
    }
}
#[derive(Copy,Clone)]
pub enum PhraseLengthFocus {
    /// Editing the number of bars
    Bar,
    /// Editing the number of beats
    Beat,
    /// Editing the number of ticks
    Tick,
}
impl PhraseLengthFocus {
    pub fn next (&mut self) {
        *self = match self {
            Self::Bar  => Self::Beat,
            Self::Beat => Self::Tick,
            Self::Tick => Self::Bar,
        }
    }
    pub fn prev (&mut self) {
        *self = match self {
            Self::Bar  => Self::Tick,
            Self::Beat => Self::Bar,
            Self::Tick => Self::Beat,
        }
    }
}