MusicUtil = require("musicutil")
engine.name = "PolyPerc"

-- we can extract a list of scale names from musicutil using the following
scale_names = {}
for i = 1, #MusicUtil.SCALES do
  table.insert(scale_names, MusicUtil.SCALES[i].name)
end

playing = false -- whether notes are playing

function init()
  engine.release(2)

  -- setting root notes using params
  params:add{type = "number", id = "root_note", name = "root note",
    min = 0, max = 127, default = 60, formatter = function(param) return MusicUtil.note_num_to_name(param:get(), true) end,
    action = function() build_scale() end} -- by employing build_scale() here, we update the scale

  -- setting scale type using params
  params:add{type = "option", id = "scale", name = "scale",
    options = scale_names, default = 5,
    action = function() build_scale() end} -- by employing build_scale() here, we update the scale
  
  -- setting how many notes from the scale can be played
  params:add{type = "number", id = "pool_size", name = "note pool size",
    min = 1, max = 32, default = 16,
    action = function() build_scale() end}

  build_scale() -- builds initial scale
end

function build_scale()
  notes_nums = MusicUtil.generate_scale_of_length(params:get("root_note"), params:get("scale"), params:get("pool_size")) -- builds scale
  notes_freq = MusicUtil.note_nums_to_freqs(notes_nums) -- converts note numbers to an array of frequencies
end

function play_notes()
  while true do
    clock.sync(1/2)
    local rnd = math.random(1,#notes_nums) -- a random integer
    current_note_num = notes_nums[rnd] -- select a random note from the scale
    engine.hz(notes_freq[rnd]) -- play note using the corresponding frequency
    current_note_name = MusicUtil.note_num_to_name(current_note_num,true) -- convert note number to name
    redraw()
  end
end

function stop_play() -- stops the coroutine playing the notes
  clock.cancel(play)
  playing = false
  redraw()
end

function key(n,z)
  if n == 2 and z == 1 then
    if not playing then
      play = clock.run(play_notes) -- starts the clock coroutine which plays a random note from the scale
      playing = true
    elseif playing then
      stop_play()
    end
  end
end

function redraw()
  screen.clear()
  screen.level(14)
  screen.move(64,32)
  if playing == true then
    screen.font_size(24)
    screen.text_center(current_note_name) -- display the name of the note that is playing
  else
    screen.font_size(8)
    screen.text_center("press k2 to play")
  end
  screen.update()
end

MusicUtil = require("musicutil")
engine.name = "PolyPerc"

playing = false -- whether notes are playing

function init()
  engine.release(2)
  build_scale() -- builds initial scale
end

function build_scale()
  notes_array = MusicUtil.generate_scale_of_length(60, "dorian", 16) -- builds quantization scale
end

function play_notes()
  while true do
    clock.sync(1/2)
    rnd = math.random(40,80)
    print("random: "..rnd)
    current_note_num = MusicUtil.snap_note_to_array(rnd,notes_array) -- snap the random number to the scale array
    print("snapped: "..current_note_num)
    engine.hz(MusicUtil.note_num_to_freq(current_note_num)) -- convert note number to freq and play
    current_note_name = MusicUtil.note_num_to_name(current_note_num,true) -- convert note number to name
    redraw()
  end
end

function stop_play() -- stops the coroutine playing the notes
  clock.cancel(play)
  playing = false
  redraw()
end

function key(n,z)
  if n == 2 and z == 1 then
    if not playing then
      play = clock.run(play_notes) -- starts the clock coroutine which plays a random note from the scale
      playing = true
    elseif playing then
      stop_play()
    end
  end
end

function redraw()
  screen.clear()
  screen.level(14)
  screen.move(64,32)
  if playing == true then
    screen.font_size(24)
    screen.text_center(current_note_name) -- display the name of the note that is playing
    screen.font_size(8)
    screen.move(128,50)
    screen.text_right("raw: "..rnd)
    screen.move(128,60)
    screen.text_right("snapped: "..current_note_num)
  else
    screen.font_size(8)
    screen.text_center("press k2 to play")
  end
  screen.update()
end