-- Advanced Tunnel by Henness
-- Version 1.3.4 1/4/2013

-- Config
Version = "v1.3.4"
HeightQuestion = false
height = 2
WidthQuestion = false
width = 2
length = 15
LengthQuestion = false
TorchesQuestion = false
torches = false

-- Functions
function version() -- Version function
    return Version
end

function clearscreen() -- Clearscreen function
    term.clear()
    regwrite( "Advanced Tunnel", 12, 1 )
    regwrite( version(), 2, 12 )
    regwrite( "Designed by Henness", 17, 12 )
    term.setCursorPos( 1, 3 )
end

function regwrite(string, columnVar, rowVar) -- Write a string to the cords
    term.setCursorPos( columnVar, rowVar )
    write (string)
end

function arcwrite(number, columnVar, rowVar) -- Write a number "right to left" to the cords
    digits = math.ceil(math.log10(number))
    if 10^digits == number then
        digits = digits + 1
    end
    term.setCursorPos( columnVar, rowVar )
    while digits > 1 do
        digits = digits - 1
        columnVar = columnVar - 1
        term.setCursorPos( columnVar, rowVar )
    end
    write (number)
end

function createtable() -- Make a table function
clearscreen()
print ( [[
 +--------------------------------+
 |Blocks Mined:                 0 |
 |Torches Placed:               0 |
 +--------------------------------+
 |             Status             |
 |[                              ]|
 |                0%              |
 +--------------------------------+
]] )
placedValue = 0
minedValue = 0
end

function updatetable() -- Update the table
    -- Update Blocks Mined
    minedValue = minedValue + 1
    arcwrite(minedValue, 33, 4)

    -- Update Percentage
    if length > 0 then
        area = (height * width * length)
    else
        area = minedValue
    end
    percentage = math.ceil((minedValue / area) * 100)
    arcwrite(percentage, 19, 9)

    -- Update Percentage Bar
    percentageBar = math.floor(percentage * 0.3)
    columnVar = 4
    while percentageBar > 0 do
        regwrite( "=", columnVar, 8 )
        percentageBar = percentageBar - 1
        columnVar = columnVar + 1
    end
end

function placetorch() -- Place a torch
    if torches == true then
        if lengthSpacingVar == 0 and ( spaceFromWallVar == 0 or widthSpacingVar == 0 ) then
            turtle.placeDown()
            if turtle.getItemCount(1) == 0 then
                noTorches = true
            end
            spaceFromWallVar = -1
            widthSpacingVar = widthSpacing
            -- Update Torches Placed
            placedValue = placedValue + 1
            arcwrite(placedValue, 33, 5)
        else
            spaceFromWallVar = spaceFromWallVar - 1
            widthSpacingVar = widthSpacingVar - 1
        end
    end
end

function widthtest() -- Test width for numbers that = 4+10n
    widthTestVar = width
    while widthTestVar > 4 do
        widthTestVar = widthTestVar - 10
    end
    if widthTestVar == 4 then
        return true
    end
end

function setspacing() -- Calculate spacing of torches
    if width < 6 then
        if math.fmod( width, 2 ) == 0 then -- If even
            if width == 2 then
                lengthSpacing = 9
                spaceFromWall = ( 1 + ( -1 )^placedValue ) / 2
            else
                lengthSpacing = 7
                spaceFromWall = (( 1 + ( -1 )^placedValue ) / 2 ) + 1
            end
        else -- If odd
            spaceFromWall = math.floor( width / 2 )
            if width == 5 then
                lengthSpacing = 6
            elseif width == 3 then
                lengthSpacing = 8
            else
                lengthSpacing = 10
            end
        end
        widthSpacing = -1
    else
        if math.fmod( width, 2 ) == 0 then -- If even
            widthSpacing = 4
            lengthSpacing = 4
            if widthtest() == true or width == 6 then
                spaceFromWall = 0
            else
                spaceFromWallVar = width
                while spaceFromWallVar > 7 do
                    spaceFromWallVar = spaceFromWallVar - ( widthSpacing + 1 )
                end
                spaceFromWall = ( spaceFromWallVar - 1 ) / 2
            end
        else -- If odd
            widthSpacing = 5
            lengthSpacing = 4
            if width == 7 then
                spaceFromWall = 0
            else
                spaceFromWallVar = width
                while spaceFromWallVar > 7 do
                    spaceFromWallVar = spaceFromWallVar - ( widthSpacing + 1 )
                end
                spaceFromWall = ( spaceFromWallVar - 1 ) / 2
            end
        end
    end
    spaceFromWallVar = spaceFromWall
    widthSpacingVar = widthSpacing
    lengthSpacingVar = lengthSpacing
end

function digdown() -- Dig down and update the table
    if turtle.detectDown() then
        turtle.digDown()
    end
    updatetable()
end

function digup() -- Dig up and update the table
    while turtle.detectUp() do
        turtle.digUp()
        sleep(0.5)
    end
    updatetable()
end

function digforward() -- Dig forward and update the table
    local moved = moveforward()
    if not moved and turtle.detect() then
        repeat turtle.dig() until moveforward()
        local moved = true
    elseif not moved and not turtle.detect() then
        repeat turtle.attack() until moveforward()
    end
    updatetable()
end

function moveforward() -- Move forward
    return turtle.forward()
end

function largetunnel() -- Mine a tunnel larger then one wide
    widthvar = width - 1
    while widthvar > 0 do
        if tunnelheight == 1 then
            digdown()
            placetorch()
            moveforward()
        end
        if tunnelheight == 2 then
            digdown()
            placetorch()
            digforward()
        end
        if tunnelheight == 3 then
            digup()
            digdown()
            placetorch()
            digforward()
        end
        if tunnelheight > 3 then
            digup()
            digdown()
            digforward()
        end
        widthvar = widthvar - 1
    end
    if tunnelheight == 1 then
        digdown()
        tunnelheight = tunnelheight - 1
    elseif tunnelheight == 2 then
        digdown()
        tunnelheight = tunnelheight - 2
    elseif tunnelheight == 3 then
        digup()
        digdown()
        tunnelheight = tunnelheight - 3
    else
        digup()
        digdown()
        tunnelheight = tunnelheight - 3
        if tunnelheight == 1 then
            turtle.down()
        end
        if tunnelheight == 2 then
            turtle.down()
            digdown()
            turtle.down()
        end
        if tunnelheight >= 3 then
            turtle.down()
            digdown()
            turtle.down()
            digdown()
            turtle.down()
        end
    end
end

function smalltunnel() -- Mine a one wide tunnel
    if tunnelheight == 2 then
        digdown()
    end
    if tunnelheight == 3 then
        digup()
        digdown()
    end
    if tunnelheight > 3 then
        digup()
        digdown()
        turtle.down()
        tunnelheight = tunnelheight - 3
        while tunnelheight > 1 do
            digdown()
            turtle.down()
            tunnelheight = tunnelheight - 1
        end
        digdown()
    end
    placetorch()
end

-- Questions
clearscreen()
while HeightQuestion == true do -- Height Question
    print("Height of tunnel?")
    height = tonumber(read())
    clearscreen()
    if height == nil then
        print( "Please answer with a number." )
    elseif height >= 2 then
        HeightQuestion = false
        startheight = height - 3
    elseif height == 1 then
        print( "The tunnel height must be larger than one." )
    elseif height == 0 then
        print( "The tunnel height can't be infinite." )
    else
        print( "The tunnel height must be positive." )
    end
end

clearscreen()
while WidthQuestion == true do -- Width Question
    print("Width of tunnel?")
    width = tonumber(read())
    clearscreen()
    if width == nil then
        print( "Please answer with a number." )
    elseif width > 0 then
        WidthQuestion = false
    elseif width == 0 then
        print( "The tunnel width can't be infinite." )
    else
        print( "The tunnel width must be positive." )
    end
end

clearscreen()
while LengthQuestion == true do -- Length Question
    print("Length of tunnel?")
    length = tonumber(read())
    clearscreen()
    if length == nil then
        print( "Please answer with a number." )
    elseif length > 0 then
        LengthQuestion = false
        lengthVar = 0
    elseif length == 0 then
        LengthQuestion = false
        Infinitelength = true
        TorchesQuestion = false
        TorchSpacingQuestion = false
        lengthVar = (-1)
    else
        print( "The tunnel length must be positive." )
    end
end

clearscreen()
while TorchesQuestion == true do -- Torch Question
    print("Place torches?")
    light = string.lower(read())
    clearscreen()
    if light == ( 'yes' ) then
        if turtle.getItemCount(1) == 0 then
            print("Please place torches in the first inventory slot.")
        else
        torches = true
        TorchesQuestion = false
        noTorches = false
        setspacing()
        lengthSpacingVar = 0
        end
    elseif light == ( 'no' ) then
        torches = false
        TorchesQuestion = false
    else
        print("Please answer yes or no.")
    end
end

-- Create the gui
createtable()

-- Mining Loop
turtle.up()
while startheight > 0 do
    local moved = turtle.up()
    if not moved and turtle.detectUp() then
        repeat turtle.digUp() until turtle.up()
        local moved = true
    elseif not moved and not turtle.detectUp() then
        repeat turtle.attackUp() until turtle.up()
    end
    startheight = startheight - 1
end
while lengthVar < length do
    lengthVar = lengthVar + 1
    digforward()
    if width > 1 then
        turtle.turnRight()
    end

    -- Mine a one wide tunnel or a larger tunnel.
    tunnelheight = height
    if width > 1 then
        while tunnelheight > 0 do
            largetunnel()
            turtle.turnRight()
            turtle.turnRight()
            if tunnelheight > 0 then
                largetunnel()
                if tunnelheight > 0 then
                    turtle.turnRight()
                    turtle.turnRight()
                end
            else
                widthvar = width - 1
                while widthvar > 0 do
                    moveforward()
                    widthvar = widthvar - 1
                end
            end
        end
    else
        smalltunnel()
    end
    if torches == true then
        if lengthSpacingVar == 0 then
            spaceFromWallVar = spaceFromWall
            widthSpacingVar = widthSpacing
            lengthSpacingVar = lengthSpacing
        else
            spaceFromWallVar = spaceFromWall
            widthSpacingVar = widthSpacing
            lengthSpacingVar = lengthSpacingVar - 1
        end
    end
    startheight = height - 3
    while startheight > 0 do
        turtle.up()
        startheight = startheight - 1
    end

    -- Infinite Length
    if Infinitelength == true then
        lengthVar = lengthVar - 1
    end

    -- Stop or Continue
    if lengthVar == length or noTorches == true then
        if width > 1 then
            turtle.turnLeft()
        else
            turtle.turnRight()
            turtle.turnRight()
        end
        while lengthVar > 0 do
            moveforward()
            lengthVar = lengthVar - 1
        end
        while startheight < ( height - 3 ) do
            turtle.down()
            startheight = startheight + 1
        end
        turtle.turnLeft()
        turtle.turnLeft()
        lengthVar = length
        term.setCursorPos( 1, 11 )
        if noTorches == true then
            print ("Out of Torches!")
        else
            print ("Tunnel Complete!")
        end
        term.setCursorPos( 1, 2 )
    else
        if width > 1 then
            turtle.turnRight()
        end
    end
end