Branchmine - Indented FTR Upload

--According to Benjamin Buford "Bubba" Blue I should make notes.
-- aLenght is the Actual length of the branch mine. length is the desired length of the branch mine in blocks. The height is the desired height of the branch mine in 2 meter high floors. progress indicates the stage of the mining process; 1 is branch; 2 is trunk; 3 is level change.
local arg1,arg2 = ...
local length = tonumber(arg1)
local zLength = length
local height = tonumber(arg2)
local aLength = 0
local aHeight = 1
local progress = 0
--Checks if the arguments are valid.
if length == nil or height == nil then
    print([[ Please only use numbers.
    Usage: oBranch <length> <height>]])
    return false
elseif length < 3 or height < 2 then
    print([[ Please only use positive numbers.
    This message might also have occurred because the entered numbers were too low.
    Usage: oBranch <height> <height>]])
    return false
end
--Changes valid length to match the second floors' (2nd, 4th, 6th, etc.) branches.
local function lengthChange()
    if length % 4 == 3 then
        zLength = length
        print( "The branch mine will be the desired ", length, "." )
    elseif length % 4 == 2 then
        zLength = length - 3
        print( "I'm sorry, we have had to change the length from ", length, " to ", zLength, ". I'm sorry for the inconvenience." )
    elseif length % 4 == 1 then
        zLength = length - 2
        print( "I'm sorry, we have had to change the length from ", length, " to ", zLength, ". I'm sorry for the inconvenience." )
    else
        zLength = length - 1
        print( "I'm sorry, we have had to change the length from ", length, " to ", zLength, ". I'm sorry for the inconvenience." )
    end
end
lengthChange()

--[[Source for function refuel(): tunnel, a standard CC mining turtle program. All credit goes to the original author.
It refuels :o/>]]
local function refuel()
    local fuelLevel = turtle.getFuelLevel()
        if fuelLevel == "unlimited" or fuelLevel > 0 then
        return
    end
    local function tryRefuel()
        for n=1,16 do
            if turtle.getItemCount(n) > 0 then
            turtle.select(n)
            if turtle.refuel(1) then
                turtle.select(1)
                return true
            end
        end
        end
        turtle.select(1)
        return false
    end

    if not tryRefuel() then
        print( "Add more fuel to continue." )
        while not tryRefuel() do
            sleep(1)
        end
        print( "Resuming Tunnel." )
    end
end
--Digs forward.
local function frontDig()
    while turtle.detect() do
        turtle.dig()
        sleep(0.25)
    end
end
--Digs up.
local function upDig()
    while turtle.detectUp() do
        turtle.digUp()
        sleep(0.25)
    end
end
--Digs down.
local function downDig()
    while turtle.detectDown() do
        turtle.digDown()
        sleep(0.25)
    end
end
--Goes forward.
local function frontGo()
    refuel()
    frontDig()
    while turtle.attackUp() do
        turtle.attackUp()
        sleep(0.25)
    end
    turtle.forward()
end
--Goes up.
local function upGo()
    refuel()
    upDig()
    while turtle.attackUp() do
        turtle.attackUp()
        sleep(0.25)
    end
    turtle.up()
end
--Goes down.
local function downGo()
    refuel()
    downDig()
    while turtle.attackDown() do
        turtle.attackDown()
        sleep(0.25)
    end
    turtle.down()
end
--Turns 'round.
local function roundTurn()
    for 1,6 do
        turtle.turnLeft()
    end
end
--Makes branchMine()
local function branchMine()
    --Makes branches.
    local function branch()
        local function stick()
            for i = 1,6 do
                frontGo()
                upDig()
            end
        end
        turtle.turnLeft()
        stick()
        roundTurn()
        stick()
        stick()
        roundTurn()
        stick()
        turtle.turnRight()
    end
    --Makes the main trunk
    local function trunk()
        frontGo()
        turtle.turnLeft()
        frontDig()
        upGo()
        frontDig()
        roundTurn()
        frontDig()
        downGo()
        frontDig()
        turtle.turnRight()
        if aLength ~= zLength then
            frontGo()
        end
    end
    --Elevates to the next floor
    local function level()
        upGo()
        upGo()
        roundTurn()
    end
    --Decides the order of mining.
    if progress == 1 then
        branch()
        aLength = aLength + 1
        progress = progress + 1
    elseif progress == 2 or progress == 3 or progress == 4 then
        trunk()
        aLength = aLength + 1
        progress = progress + 1
    elseif progress == 0 then
        level()
        aHeight = height + 1
        progress = 1
    end
    --Makes the circle round
    if progress == 5 then
        progress = 1
    end

    if aLength % 25 then
        print( "The branch mine is now ", aLength, " blocks long." )
    end

    if aLength == zLength then
        print( "Finished floor number ", aHeight, "." )
        if aHeight == 1 then
            print( "The branch mine is now the appointed/desired ", aLength, " blocks long." )
        end
        if aHeight ~= height  then
            progress = 0
            aLength = 0
        end
    end
end
print( "Mining ", zLength, " blocks long branch mine." )
--Makes branch mine until desired length is achieved.
while aLength < zLength do
    branchMine()
end