local args = {...}

function split (inputstr, sep)
    if sep == nil then
            sep = "%s"
    end
    local t={}
    for str in string.gmatch(inputstr, "([^"..sep.."]+)") do
            table.insert(t, str)
    end
    return t
end

local commands = {}

commands["w"] = function()
    return turtle.forward()
end

commands["up"] = function()
    return turtle.up()
end

commands["down"] = function()
    return turtle.down()
end

commands["a"] = function()
    return turtle.turnLeft()
end

commands["d"] = function()
    return turtle.turnRight()
end

commands["dig"] = function()
    return turtle.dig()
end

commands["digup"] = function()
    return turtle.digUp()
end

commands["digdown"] = function()
    return turtle.digDown()
end

commands["place"] = function()
    return turtle.place()
end

commands["placeup"] = function()
    return turtle.placeUp()
end

commands["placedown"] = function()
    return turtle.placeDown()
end

commands["refuel"] = function()
    turtle.refuel()
    return "Fuel: " .. turtle.getFuelLevel()
end

local cnum = 1
commands["nextslot"] = function()
    cnum = cnum + 1
    if turtle.select(cnum) then
        if turtle.getItemDetail(turtle.getSelectedSlot()) == nil then
            return "Empty Slot " .. turtle.getSelectedSlot()
        end
        return turtle.getItemDetail(turtle.getSelectedSlot()).name .. ": " .. turtle.getSelectedSlot()
    end
end

commands["prevslot"] = function()
    cnum = cnum - 1
    if turtle.select(cnum) then
        if turtle.getItemDetail(turtle.getSelectedSlot()) == nil then
            return "Empty Slot " .. turtle.getSelectedSlot()
        end
        return turtle.getItemDetail(turtle.getSelectedSlot()).name .. ": " .. turtle.getSelectedSlot()
    end
end

local side = args[1]
if side == nil then
    side = "left"
end


rednet.open(side)
while true do
    senderID, message, distance = rednet.receive()

    local cmds = split(message, " ")
    for i,v in pairs(cmds) do
        local toExec = commands[v]
        if toExec then
            local rmsg = toExec()
            rednet.send(senderID, rmsg)
        else
            rednet.send(senderID, "Invalid command!")
        end
    end
end
rednet.close(side)