OCStepSequencer

local computer = require("computer")
local fs = require("filesystem")
local serial = require("serialization")
local term = require("term")
local event = require("event")
local component = require("component")
local gpu = component.gpu
local note = component.note_block

a = {...}
filename = "c/songs/"..a[1]
timeSig = tonumber(a[2])
detail = tonumber(a[3])

currentBar = 1
bpm = 120

if not fs.isDirectory("c/songs") then fs.makeDirectory("c/songs") end
if timeSig == nil then timeSig = 4 end
if bpm == nil then bpm = 120 end
if detail == nil then detail = 4 end

if detail == nil then detail = 4 end

function newScore()
    score = nil
    score = {}
    score.bpm = bpm
    barCount = 0
end

function loadScore(filepath)
    file = io.open(filepath, "r")
    score = serial.unserialize(file:read("*all"))
    file:close()
    barCount = score.barCount
    bpm = score.bpm
end

function saveScore()
    score.barCount = barCount
    score.bpm = bpm
    file = io.open(filename, "w")
    file:write(serial.serialize(score))
    file:close()
end

function fixTempo(beats)
    tempo = 60 / beats
    tempo = tempo / detail
    gpu.setBackground(0x000000)
    gpu.setForeground(0xFFFFFF)
    gpu.set(1, y, currentBar.."/"..barCount.."            "..bpm.." BPM")
end

function addBar(beats)
    barCount = barCount + 1
    score[barCount] = {}
    for i = 1, beats * detail do
        score[barCount][i] = "rest"
    end
end

function playNote(note)
    note.trigger(note)
end

function noteCaller()
    octCount = 0
    noteCount = 0
    noteString = "A1BC2D3EF4G5"
    notePos = 0
    noteTab = {}
    for i = 1, 25 do
        notePos = notePos + 1
        noteCount = noteCount + 1
        noteVal = string.sub(noteString, notePos, notePos)
        if noteVal == "1" then
            noteVal = "A#"
        elseif noteVal == "2" then
            noteVal = "C#"
        elseif noteVal == "3" then
            noteVal = "D#"
        elseif noteVal == "4" then
            noteVal = "F#"
        elseif noteVal == "5" then
            noteVal = "G#"
        end
        label = noteVal..octCount
        noteTab[noteCount] = {}
        noteTab[noteCount]["label"] = label
        noteTab[noteCount]["note"] = i
        if noteVal == "G#" then
            notePos = 0
            octCount = octCount + 1
        end
    end
end

function addButton(label, bType, xPos, yPos, w, h, col1, col2, retVal, retVal2)
    if buttonTab == nil then
        buttonTab = {}
        buttonCount = 0
    end
    buttonCount = buttonCount + 1
    buttonTab[buttonCount] = {
        label = label,
        bType = bType,
        xPos = xPos,
        yPos = yPos,
        width = w,
        height = h,
        colour = col1,
        pCol = col1,
        tCol = col2,
        retVal = retVal,
        retVal2 = retVal2,
        active = false,
        }
end

function initKeys()
    x, y = gpu.getResolution()
    bWidth = 4
    yStart = y - 15
    for i = 1, #noteTab do
        if string.sub(noteTab[i]["label"], 2, 2) == "#" then
            col = 0x000000
            tCol = 0xFFFFFF
            pCol = 0xFF0000
            bCol = 0x0000FF
            pTCol = 0x000000
        else
            col = 0xFFFFFF
            tCol = 0x000000
            pCol = 0xFF6666
            bCol = 0x6666FF
            pTCol = 0x000000
        end
        addButton(noteTab[i]["label"], "note", 1, yStart - i, 10, 1, col, tCol, noteTab[i]["note"])
        for j = 1, timeSig * detail do
            if j % detail == 1 then
                addButton("[<>]", "pad", 11 + (bWidth), yStart - i, 3, 1, bCol, pTCol, j, noteTab[i]["note"])
            else
                addButton("[<>]", "pad", 11 + (bWidth), yStart - i, 3, 1, pCol, pTCol, j, noteTab[i]["note"])
            end
            if j == timeSig * detail then
                bWidth = 4
            else
                bWidth = bWidth + 4
            end
        end
    end
end

function drawScreen(bar)
    gpu.setBackground(0x000000)
    term.clear()
    for i = 1, #buttonTab do
        gpu.setBackground(buttonTab[i]["colour"])
        gpu.setForeground(buttonTab[i]["tCol"])
        if buttonTab[i]["bType"] ~= "pad" then
            gpu.fill(buttonTab[i]["xPos"], buttonTab[i]["yPos"], buttonTab[i]["width"], buttonTab[i]["height"], " ")
            offset = math.floor((buttonTab[i]["width"] - #buttonTab[i]["label"]) / 2)
            if buttonTab[i]["height"] > 1 then
                yOffset = math.floor((buttonTab[i]["height"] /2))
                gpu.set(buttonTab[i]["xPos"] + offset, buttonTab[i]["yPos"] + yOffset, buttonTab[i]["label"])
            else
                gpu.set(buttonTab[i]["xPos"] + offset, buttonTab[i]["yPos"], buttonTab[i]["label"])
            end
        else
            if score[bar][buttonTab[i]["retVal"]] == buttonTab[i]["retVal2"] then
                buttonTab[i]["label"] = "[><]"
                buttonTab[i]["active"] = true
                buttonTab[i]["colour"] = 0x66FF66
            else
                buttonTab[i]["label"] = "[<>]"
                buttonTab[i]["active"] = true
                buttonTab[i]["colour"] = buttonTab[i]["pCol"]
            end
            gpu.setBackground(buttonTab[i]["colour"])
            gpu.set(buttonTab[i]["xPos"], buttonTab[i]["yPos"], buttonTab[i]["label"])
        end
    end
    gpu.setBackground(0x000000)
    gpu.setForeground(0xFFFFFF)
    gpu.set(1, y, currentBar.."/"..barCount.."            "..bpm.." BPM")
end

function play()
    for j = 1, #score do
        for k = 1, #score[j] do
            if score[j][k] ~= "rest" then
                note.trigger(score[j][k])
            end
            ev = event.pull(tempo, _, ev)
            if ev == "touch" then
                return true
            end
        end
    end
end

function run()
    ev, sa, p1, p2, p3, p4 = event.pull(.1, _, ev, sa, p1, p2, p3, p4)
    if ev == "key_down" then
        running = false
        return
    elseif ev == "touch" or ev =="drag" then
        for i = 1, #buttonTab do
            if p1 >= buttonTab[i]["xPos"] and p1 <= buttonTab[i]["xPos"] + buttonTab[i]["width"] then
                if p2 >= buttonTab[i]["yPos"] and p2 <= buttonTab[i]["yPos"] + (buttonTab[i]["height"] - 1) then
                    if buttonTab[i]["bType"] == "note" then
                        gpu.setBackground(0x66FF66)
                        gpu.fill(buttonTab[i]["xPos"], buttonTab[i]["yPos"], buttonTab[i]["width"], buttonTab[i]["height"], " ")
                        note.trigger(buttonTab[i]["retVal"])
                        gpu.setBackground(buttonTab[i]["colour"])
                        gpu.setForeground(buttonTab[i]["tCol"])
                        gpu.fill(buttonTab[i]["xPos"], buttonTab[i]["yPos"], buttonTab[i]["width"], buttonTab[i]["height"], " ")
                        offset = math.floor((buttonTab[i]["width"] - #buttonTab[i]["label"]) / 2)
                        gpu.set(buttonTab[i]["xPos"] + offset, buttonTab[i]["yPos"], buttonTab[i]["label"])
                        return
                    elseif buttonTab[i]["bType"] == "pad" then
                        buttonTab[i]["active"] = not buttonTab[i]["active"]
                        if buttonTab[i]["active"] then
                            buttonTab[i]["colour"] = 0x66FF66
                            buttonTab[i]["label"] = "[><]"
                            score[currentBar][buttonTab[i]["retVal"]] = buttonTab[i]["retVal2"]
                            note.trigger(buttonTab[i]["retVal2"])
                        else
                            buttonTab[i]["colour"] = buttonTab[i]["pCol"]
                            buttonTab[i]["label"] = "[<>]"
                            score[currentBar][buttonTab[i]["retVal"]] = "rest"
                        end
                        gpu.setBackground(buttonTab[i]["colour"])
                        gpu.setForeground(buttonTab[i]["tCol"])
                        gpu.set(buttonTab[i]["xPos"], buttonTab[i]["yPos"], buttonTab[i]["label"])
                    elseif buttonTab[i]["bType"] == "save" then
                        saveScore()
                    elseif buttonTab[i]["bType"] == "loop" then
                        if buttonTab[i]["active"] then
                            loopBool = false
                            buttonTab[i]["active"] = false
                        else
                            loopBool = true
                            buttonTab[i]["active"] = true
                        end
                    elseif buttonTab[i]["bType"] == "play" then
                        if loopBool then
                            while true do
                                if play() then return end
                            end
                        else
                            play()
                        end
                    elseif buttonTab[i]["bType"] == "<<" then
                        if currentBar > 1 then currentBar = currentBar - 1 end
                        drawScreen(currentBar)
                    elseif buttonTab[i]["bType"] == ">>" then
                        if currentBar < barCount then
                            currentBar = currentBar + 1
                            drawScreen(currentBar)
                        else
                            addBar(timeSig)
                            currentBar = currentBar + 1
                            drawScreen(currentBar)
                        end
                    elseif buttonTab[i]["bType"] == "^" then
                        bpm = bpm + 1
                        fixTempo(bpm)
                    elseif buttonTab[i]["bType"] == "v" then
                        bpm = bpm - 1
                        fixTempo(bpm)
                    end
                end
            end
        end
    end
end

noteCaller()
initKeys()
if fs.exists(filename) then
    loadScore(filename)
else
    newScore()
end
addBar(timeSig)
currentBar = 1
fixTempo(bpm)
addButton("Save", "save", 1, 1, 10, 3, 0xFFFFFF, 0x000000)
addButton("Loop", "loop", 21, 1, 10, 3, 0x00FFFF, 0x000000)
addButton("Play", "play", 31, 1, 10, 3, 0x66FF66, 0x000000)
addButton("<<", "<<", 41, 1, 10, 3, 0x6666FF, 0x000000)
addButton(">>", ">>", 51, 1, 10, 3, 0x6666FF, 0x000000)
addButton("^", "^", 61, 1, 10, 3, 0x66FF66, 0x000000)
addButton("v", "v", 71, 1, 10, 3, 0x66FF66, 0x000000)
drawScreen(currentBar)
running = true
while running do
    run()
end
gpu.setBackground(0x000000)
gpu.setForeground(0xFFFFFF)
term.clear()