chamber

print ("How long should the room be?")
local length = tonumber(io.read())
print ("How wide should the room be?")
local width = tonumber(io.read())
print ("How high should the room be?")
local height = tonumber(io.read())

xPos = 0 -- Initalise positions. Positive x = forward from starting direction
yPos = 0 -- Positive y = right from starting position
zPos = 0 -- Positive z = up from starting position
dir = 1  -- initalize direction 1 = ahead, 2 = right, 3 = back, 4 = left, relative to inital position
xMods = {1,0,-1,0} -- index xMods[dir] indicates how x will change on a turtle.forward()
yMods = {0,1,0,-1} --  index xMods[dir] indicates how x will change on a turtle.forward()
fuelThreshold = 10 -- below what fuel level will the turtle refuel itself?


local function setHeight(targetZ) -- moves the turtle to the target height, bashing any obstructions clear
    while zPos < targetZ do
        if turtle.detectUp() then
            turtle.digUp()
        end
        if turtle.up() then
            zPos = zPos + 1
        end
    end
    while zPos > targetZ do
        if turtle.detectDown() then
            turtle.digDown()
        end
        if turtle.down() then
            zPos = zPos - 1
        end
    end
end

local function right() -- turns right once
    turtle.turnRight()
    dir = dir + 1
    if dir > 4 then --makes sure dir is in the 1-4 range
        dir = dir - 4
    end
end

local function left() -- turns left once
    turtle.turnLeft()
    dir = dir - 1
    if dir < 1 then --makes sure dir is in the 1-4 range
        dir = dir + 4
    end
end


local function turnTo(targetDir) -- turns right untl facing the right way (TODO: Find a way of making it turn the shortest way whish isn't just one long list of special cases)
    while  targetDir ~= dir do
        right()
    end
end

local function checkFuel() -- ensure the turtle as enough fuel
    if turtle.getFuelLevel ~= "unlimited" -- check that turtles even need fuel
    then
        if turtle.getFuelLevel() < fuelThreshold -- if fuel is below the threshold...
        then
            i = 1
            needFuel = true
            while  needFuel do
                turtle.select(i) -- then step through the slots
                if turtle.refuel(1) -- and try to use 1 fuel
                then
                    if turtle.getFuelLevel() > fuelThreshold            -- if fueled, then done
                    then
                        needFuel = false
                    end
                else
                    if i < 16
                    then
                        i = i + 1
                    else
                        print("No fuel left!")
                        sleep(1)
                        needFuel = false
                    end
                end
            end
        end
    end
end

local function forward(distance)  -- Simple go forward, smash anything in the way. (TODO: add a simple evasion routine)
    local i = 0
    while i < distance do
        if turtle.detect() then --  is there anything in the way? Smash it then
            turtle.dig()
        end
        checkFuel()
        if turtle.forward() then  -- go forward, count if you actually move
            i = i + 1
            xPos = xPos + xMods[dir]
            yPos = yPos + yMods[dir]
        end
    end
    -- print("At end of forward command, I am at ("..xPos..","..yPos..","..zPos..")") -- decomment this to see where the turtle thinks it is
end

local function navigateTo(targetX,targetY,targetZ)  -- navigates to a relative coordinate, smashing everything it it's way. USE WITH CAUTION
    -- print("Moving to (" .. targetX ..","..targetY..","..targetZ..")")  -- decomment this to see where the turtle thinks it is going
    if xPos < targetX then
        turnTo(1)
        forward(targetX - xPos)
    end
    if xPos > targetX then
        turnTo(3)
        forward(xPos - targetX)
    end
    if yPos < targetY then
        turnTo(2)
        forward(targetY - yPos)
    end
    if yPos > targetY then
        turnTo(4)
        forward(yPos - targetY)
    end
    setHeight(targetZ)
end

for z=0,(height-1),3 do
    if z < (height -1) then
        zLevel = z+1
        digDown = true
        if z < (height - 2)
        then
            digUp = true
        else
            digUp = false
        end
    else
        zLevel = z
        digUp = false
        digDown = false
    end
    upTheRow = true
    for y = 0, (width - 1) do
        if upTheRow
        then
            startX = 0
            endX = (length -1)
            modX = 1
            upTheRow = false
        else
            startX = (length -1)
            endX = 0
            modX = -1
            upTheRow = true
        end
        for x = startX, endX, modX do
            navigateTo(x,y,zLevel)
            if digUp then
                while turtle.detectUp() do
                    turtle.digUp()
                end
            end
            if digDown then
                while turtle.detectDown() do
                    turtle.digDown()
                end
            end
        end
    end
end

navigateTo(0,0,0)