Protoplug LUA midi plugin - play midi channel 2 exclusive, note off other notes during playing (perfect arp melody maker)

protoplug-channel2-exclusive.lua

require "include/protoplug"


local buffer = {}
local channelOneActive = false

function mydebug(ev, skipped)
    local onoff = "On"
    local skip = "skipped"
    if not skipped then
        skip = ""
    end
    if ev:isNoteOff() then
        onoff = "Off"
    end
    if ev:getChannel()==1 then
        --print("Note " .. onoff .. " " .. ev:getNote() .. ";" .. ev.time .. ";" .. skip)
    elseif ev:getChannel()==2 then
        --print("            ;Note " .. onoff .. " " .. ev:getNote() .. ";"  .. ev.time .. ";" .. skip)
    end
end

function plugin.processBlock(samples, smax, midiBuf)
    for ev in midiBuf:eachEvent() do
        if ev:isNoteOn() or ev:isNoteOff() then
            table.insert(buffer, ev)
        end
    end
    midiBuf:clear()
    for k,n in ipairs(buffer) do
        if buffer[k]:getChannel()==1 then
            if buffer[k]:isNoteOn() then
                channelOneActive = true
            elseif buffer[k]:isNoteOff() then
                channelOneActive = false
            end
        end
        local skipped = true
        if not channelOneActive or buffer[k]:getChannel()==1 then
            skipped = false
            mydebug(buffer[k],skipped)
            if buffer[k]:isNoteOn() then
                midiBuf:addEvent(midi.Event.noteOn(1,buffer[k]:getNote(),buffer[k]:getVel()))
            end
            if buffer[k]:isNoteOff() then
                midiBuf:addEvent(midi.Event.noteOff(1,buffer[k]:getNote()))
            end
        else
            mydebug(buffer[k],skipped)
        end
    end    
    buffer = {}
end