ComputerCraft Flatten Area Script

local sizex, sizey, right = ...
local sizex = tonumber(sizex or 50)
local sizey = tonumber(sizey or 50)

function digForward()
    while not turtle.forward() do
        turtle.dig()
    end
end

function match(s)
    s = s:lower()
    local a = false
    for i, p in ipairs(blocks) do
        a = a or string.find(s, p:lower())
    end
    return a
end

function clear()
    local height = 0
    while turtle.detectUp() or turtle.detect() do
        if turtle.detectUp() then turtle.digUp() end
        if turtle.detect() then turtle.dig() end
        if turtle.up() then
            height = height + 1
        end
    end
    digForward()
    digForward()
    while turtle.detectUp() or turtle.detect() do
        if turtle.detectUp() then turtle.digUp() end
        if turtle.up() then
            height = height + 1
        end
    end
    for i = 1, height do
        if turtle.detect() then turtle.dig() end
        while not turtle.down() do turtle.digDown() end
    end
    digForward()
end

turtle.select(1)
for x = 1, sizex do
    for y = 1, math.ceil(sizey/4) do
        --[[local a, b = turtle.inspectDown()
        if a and not (b.name:lower():find('dirt') or b.name:lower():find('grass')) then
            turtle.digDown()
        end
        if ((not turtle.detectDown()) and (turtle.getItemCount(1) > 1)) then
            turtle.placeDown()
        end]]
        clear()
        digForward()
    end
    if right then
        turtle.turnRight()
        digForward()
        turtle.turnRight()
    else
        turtle.turnLeft()
        digForward()
        turtle.turnLeft()
    end
    right = not right
    digForward()
end