-- Remember to put a chest directly behind the turtle at it's current location.
-- It will deliver it's resources to this chest when full

-- Y Level to Branch-mine at
local BranchMineLevel = 5

-- How many blocks on the ignore list
-- that you put in the first number of slots
local IgnoreSlots = 4

-- Set this to true if it is ok for the turtle to mine strait down to the y level for the Branch mine
local MineDown = true
local TunnelLength = 1000

-- Set this to false if you don't have a working GPS system
local UseGPS = true
--ALL THIS MUST BE FILLED IN IF YOU DON"T USE GPS
local StartX = 0
local StartY = 0
local StartZ = 0
-- EX: "SOUTH", "NORTH", "EAST", "WEST"
local ForwardFacingDirection = ""
--END NO GPS FILL INFORMATION



--DO NOT TOUCH ANYTHING BELOW THIS LINE
local mov = {}
local rot = {}
local dig = {}
local PositionInBranchMine = 0
local RotatePosition = "FORWARD"

local InsertedIntoLeftWall = false
local InsertedIntoRightWall = false
local InsertionAmount = 0

local XX, YY, ZZ = 0;
local PrimaryAxis = ""
local SecondaryAxis = ""

local function Refuel()
	currentFuelRequired = 10 + ((PositionInBranchMine/TunnelLength)*20)
	if turtle.getFuelLevel() < currentFuelRequired then
		turtle.select(16)
		return turtle.refuel(currentFuelRequired)
	else
		return true
	end
end


local function readLines(sPath)
  local file = fs.open(sPath, "r") -- open the file
  if file then -- check if it's open
    local tLines = {} -- table to store the lines
    local sLine = file.readLine() -- read a line from the file
    while sLine do -- while there's a line in the file
          table.insert(tLines, sLine) -- add it to the table
          sLine = file.readLine() -- get the next line
    end
    file.close() -- close the file
    return tLines -- return the table with the lines
  end
  return nil -- there was an error opening the file, return nil to let the user know
end

local function writeLines(sPath, tLines)
  local file = fs.open(sPath, "w") -- open the file
  if file then -- check if the file is open
    for _, sLine in ipairs(tLines) do -- for each line in the table
          file.writeLine(sLine) -- write the line
    end
    file.close() -- close the file
  end
end

function filereadline(filename, line)
  local tLines = readLines(filename) -- read the lines from the file (using the previous functions)
  if not tLines then -- if there was an error
    return nil -- return nil/error
  end
  return tLines[line] -- return the line
end

function filewriteline(filename, line, text)
  local tLines = readLines(filename) -- read the lines from the file (using the previous functions)
  if tLines then -- if there was no error
    tLines[line] = text -- set the line
    writeLines(filename, tLines) -- write the lines back to the file (using the previous functions)
  end
end

local function incrementCoordinates(incX,incY,incZ)
XX = XX + incX
YY = YY + incY
ZZ = ZZ + incZ
filewriteline("BranchMineData", 7, XX)
filewriteline("BranchMineData", 8, YY)
filewriteline("BranchMineData", 9, ZZ)
end

--directionInteger 0 = forward, 1 = left, 2 = backward, 3 = right, 4 = up, 5 = down
local function updateCoordinates(directionInteger)
	--Displace the direction by the current Rotation
	if directionInteger <= 3 then
		if directionInteger == 0 then
			if string.match(RotatePosition,"LEFT") then
				directionInteger = 1
			elseif string.match(RotatePosition,"BACKWARD") then
				directionInteger = 2
			elseif string.match(RotatePosition,"RIGHT") then
				directionInteger = 3
			end
		elseif directionInteger == 2 then
			if string.match(RotatePosition,"LEFT") then
				directionInteger = 3
			elseif string.match(RotatePosition,"BACKWARD") then
				directionInteger = 0
			elseif string.match(RotatePosition,"RIGHT") then
				directionInteger = 1
			end
		end
	end

	local incrementPrimary = true
	local incrementBy = 0
	local incrementX = 0
	local incrementY = 0
	local incrementZ = 0
	--if we are moving forward
	if directionInteger == 0 then
		incrementPrimary = true
		incrementBy = 1
	--if we are moving left
	elseif directionInteger == 1 then
		incrementPrimary = false
		incrementBy = 1
	--if we are moving backward
	elseif directionInteger == 2 then
		incrementPrimary = true
		incrementBy = -1
	--if we are moving right
	elseif directionInteger == 3 then
		incrementPrimary =false
		incrementBy = -1
	elseif directionInteger == 4 then
		incrementY = 1
	elseif directionInteger == 5 then
		incrementY = -1
	end

	if incrementPrimary then
		if PrimaryAxis == "X" then
			incrementX = incrementBy
		elseif PrimaryAxis == "-X" then
			incrementX = -1 * incrementBy
		elseif PrimaryAxis == "Z" then
			incrementZ = incrementBy
		elseif PrimaryAxis == "-Z" then
			incrementZ = -1 * incrementBy
		end
	else
		if SecondaryAxis == "X" then
			incrementX = incrementBy
		elseif SecondaryAxis == "-X" then
			incrementX = -1 * incrementBy
		elseif SecondaryAxis == "Z" then
			incrementZ = incrementBy
		elseif SecondaryAxis == "-Z" then
			incrementZ = -1 * incrementBy
		end
	end
	incrementCoordinates(incrementX,incrementY,incrementZ)
end

mov.forward = function(times)
	local boolean v = false
	for i=1,times do
		if turtle.detect() == false then
			while not turtle.forward() do
				Refuel()
				sleep(1)
			end
			updateCoordinates(0)
			v = true
		else
			v = false
			return v
		end
	end
	return v
end

mov.back = function(times)
	local boolean v = false
	for i=1,times do
		while not turtle.back() do
			Refuel()
			sleep(1)
		end
		updateCoordinates(2)
		v = true
	end
	return v
end

mov.up = function(times)
	local boolean v = false
	for i=1,times do
		if turtle.detectUp() == false then
			while not turtle.up() do
				Refuel()
				sleep(1)
			end
			updateCoordinates(4)
			v = true
		else
			v = false
			return v
		end
	end
	return v
end

mov.down = function(times)
	local boolean v = false
	for i=1,times do
		if turtle.detectDown() == false then
			while not turtle.down() do
				Refuel()
				sleep(1)
			end
			updateCoordinates(5)
			v = true
		else
			v = false
			return v
		end
	end
	return v
end

mov.place = function()
    while not turtle.place() do
          sleep(1)
    end
    return true
end

rot.right = function()
    while not turtle.turnRight() do
            sleep(1)
    end
	
	if RotatePosition == "FORWARD" then
		RotatePosition = "RIGHT"
	elseif RotatePosition == "RIGHT" then
		RotatePosition = "BACKWARD"
	elseif RotatePosition == "BACKWARD" then
		RotatePosition = "LEFT"
	elseif RotatePosition == "LEFT" then
		RotatePosition = "FORWARD"
	end
	filewriteline("BranchMineData", 5, RotatePosition)
    return true
end

rot.left = function()
    while not turtle.turnLeft() do
            sleep(1)
    end
	
	if RotatePosition == "FORWARD" then
		RotatePosition = "LEFT"
	elseif RotatePosition == "LEFT" then
		RotatePosition = "BACKWARD"
	elseif RotatePosition == "BACKWARD" then
		RotatePosition = "RIGHT"
	elseif RotatePosition == "RIGHT" then
		RotatePosition = "FORWARD"
	end
	filewriteline("BranchMineData", 5, RotatePosition)
    return true
end

-- RotateTo is a number where 0 = Forward, 1 = Left, 2 = Backward, and 3 = Right
local function look(RotateTo)
	--This rids one odd occurance
	if RotatePosition == "RIGHT" and RotateTo == 0 then
		rot.left()
		return
	end
	--

	rotateNumber = 0
	if RotatePosition == "LEFT" then
		rotateNumber = 1
	elseif RotatePosition == "BACKWARD" then
		rotateNumber = 2
	elseif RotatePosition == "RIGHT" then
		rotateNumber = 3
	end

	rotateRight = rotateNumber - RotateTo
	if rotateRight >= 0 then
			for i = 1,rotateRight do
				rot.right()
			end
	else
			for i = 1,math.abs(rotateRight) do
				rot.left()
			end
	end

end

dig.forward = function()
	if turtle.detect() then
		while not turtle.dig() do
				sleep(1)
		end
		return true
	else
		print("No Block to mine forward")
		return false
	end
end

dig.up = function()
	if turtle.detectUp() then
		while not turtle.digUp() do
				sleep(1)
		end
		return true
	else
		print("No Block to mine up")
		return false
	end
end

dig.down = function()
	if turtle.detectDown() then
		while not turtle.digDown() do
				sleep(1)
		end
		return true
	else
		print("No Block to mine down")
		return false
	end
end

local function DigMoveForward()
	if mov.forward(1) == false then
		dig.forward()
		sleep(0.5)
		DigMoveForward()
	end
end

local function DigMoveUp()
	if mov.up(1) == false then
		dig.up()
		sleep(0.5)
		DigMoveUp()
	end
end

local function DigMoveDown()
	if mov.down(1) == false then
		dig.down()
		sleep(0.5)
		DigMoveDown()
	end
end

-- Begin BranchMining Code
if UseGPS then
	if rednet.open("right") == nil then
		print("You had GPS Enabled but there is not a modem on this turtle")
		return
	end
end
-- Mine to BranchMining level
local function MineToMine()
	local x, y, z = 0
if UseGPS then
	x, y, z = gps.locate(5)
else
	x = XX
	y = YY
	z = ZZ
end
if MineDown then
	x = tonumber(x)
	y = tonumber(y)
	z = tonumber(z)
	if y > BranchMineLevel then
		MineCount = y - BranchMineLevel
		for i = 1,MineCount do
			if mov.down(1) then
--				Print("Coords: ",x," ",y - i," ",z)
			else
				dig.down()
				mov.down(1)
--				Print("Coords: ",x," ",y - i," ",z)
			end
		end
	elseif y < BranchMineLevel then
		MineCount = BranchMineLevel - y
		for i = 1,MineCount do
			if mov.up(1) then
--				Print("Coords: ",x," ",y - i," ",z)
			else
				dig.up()
				mov.up(1)
--				Print("Coords: ",x," ",y - i," ",z)
			end
		end
	end
end
	for i = 1,tonumber(PositionInBranchMine) do
		DigMoveForward()
	end
end

local function DepositChest()
	print("Depositing the Load...")
	for i = IgnoreSlots + 1,15 do
		turtle.select(i)
		turtle.drop()
	end
end

local function GetCoalChest()
	look(1) -- look left
	turtle.select(15)
	if turtle.suck() == false then
		rot.right()
		return false
	else
		if turtle.compareTo(16) then
			turtle.transferTo(16)
			turtle.drop()
			rot.right()
			return true
		else
			turtle.drop()
			rot.right()
			return false
		end
	end
end

local function ReturnBack()
	local xC, yC, zC  = 0
if UseGPS then
	xC, yC, zC = gps.locate(5)
else
	xC = XX
	yC = YY
	zC = ZZ
end
look(2) -- look backward
Distance = 0
xC = tonumber(xC)
yC = tonumber(yC)
zC = tonumber(zC)
StartX = tonumber(StartX)
StartY = tonumber(StartY)
StartZ = tonumber(StartZ)
if xC < StartX then
	Distance = StartX - xC
elseif xC > StartX then
	Distance = xC - StartX
elseif zC < StartZ then
	Distance = StartZ - zC
elseif zC > StartZ then
	Distance = zC - StartZ
end

for i = 1,Distance do
	if mov.forward(1) == false then
		dig.forward()
		mov.forward(1)
	end
end
look(0) -- look forward
filewriteline("BranchMineData", 5, RotatePosition)
if UseGPS then
	xC, yC, zC = gps.locate(5)
else
	xC = XX
	yC = YY
	zC = ZZ
end
xC = tonumber(xC)
yC = tonumber(yC)
zC = tonumber(zC)
StartX = tonumber(StartX)
StartY = tonumber(StartY)
StartZ = tonumber(StartZ)
	if StartY > yC then
		mov.up(StartY - yC)
	elseif StartY < yC then
		mov.down(yC - StartY)
	end
	
	DepositChest()
	if GetCoalChest() == false then
		if Refuel() == false then
			print("***Out of fuel***")
			print("***NO FUEL IN CHEST, PROGRAM HALT***")
			return
		else
			print("Returning to Mine")
			MineToMine()
			StartMining()
		end
	else
		print("Returning to Mine")
		MineToMine()
		StartMining()
	end
end

local function Finish()
	local xC, yC, zC = 0
if UseGPS then
	xC, yC, zC = gps.locate(5)
else
	xC = XX
	yC = YY
	zC = ZZ
end
look(2) -- look Backward
RotatePosition = "BACKWARD"
filewriteline("BranchMineData", 5, RotatePosition)
Distance = 0
if xC < StartX then
	Distance = StartX - xC
elseif xC > StartX then
	Distance = xC - StartX
elseif zC < StartZ then
	Distance = StartZ - zC
elseif zC > StartZ then
	Distance = zC - StartZ
end

for i = 1,Distance do
	if mov.forward(1) == false then
		dig.forward()
		mov.forward(1)
	end
end
look(0) -- look Forward
RotatePosition = "FORWARD"
filewriteline("BranchMineData", 5, RotatePosition)
if UseGPS then
	xC, yC, zC = gps.locate(5)
else
	xC = XX
	yC = YY
	zC = ZZ
end

	if StartY > yC then
		mov.up(StartY - yC)
	elseif StartY < yC then
		mov.down(yC - StartY)
	end
	
	DepositChest()
	print("Finished!")
end

local function checkDown()
	TimesChecked = 0
	for i = 1,tonumber(IgnoreSlots) do
		turtle.select(i)
		if turtle.compareDown() == false then
			TimesChecked = TimesChecked + 1
			if TimesChecked == IgnoreSlots then
				dig.down()
			end
		else
			return
		end
	end
end

local function checkUp()
	TimesChecked = 0
	for i = 1,tonumber(IgnoreSlots) do
		turtle.select(i)
		if turtle.compareUp() == false then
			TimesChecked = TimesChecked + 1
			if TimesChecked == IgnoreSlots then
				dig.up()
			end
		else
			return
		end
	end
end

local function checkFront(leftWall,shouldCheckUp)
	TimesChecked = 0
	for i = 1,tonumber(IgnoreSlots) do
		turtle.select(i)
		if turtle.detect() and turtle.compare() == false then
			TimesChecked = TimesChecked + 1
			if TimesChecked == IgnoreSlots then
				DigMoveForward()
				InsertionAmount = InsertionAmount + 1
				InsertedIntoLeftWall = leftWall
				if leftWall == false then
					InsertedIntoRightWall = true
				else
					InsertedIntoRightWall = false
				end
				filewriteline("BranchMineData", 10, InsertedIntoLeftWall)
				filewriteline("BranchMineData", 11, InsertedIntoRightWall)
				filewriteline("BranchMineData", 12, InsertionAmount)
				filewriteline("BranchMineData", 13, shouldCheckUp)
				if shouldCheckUp then
					checkUp()
				else
					checkDown()
				end
				return checkFront(leftWall, shouldCheckUp)
			end
		else
			if InsertedIntoLeftWall then
				look(3) --look right
				for i = 1,tonumber(InsertionAmount) do
					DigMoveForward()
				end
				InsertedIntoRightWall = false
				InsertedIntoLeftWall = false
				InsertionAmount = 0
			elseif InsertedIntoRightWall then
				look(1) --look left
				for i = 1,tonumber(InsertionAmount) do
					DigMoveForward()
				end
				InsertedIntoRightWall = false
				InsertedIntoLeftWall = false
				InsertionAmount = 0
			else
				filewriteline("BranchMineData", 10, InsertedIntoLeftWall)
				filewriteline("BranchMineData", 11, InsertedIntoRightWall)
				filewriteline("BranchMineData", 12, InsertionAmount)
				return false
			end
				filewriteline("BranchMineData", 10, InsertedIntoLeftWall)
				filewriteline("BranchMineData", 11, InsertedIntoRightWall)
				filewriteline("BranchMineData", 12, InsertionAmount)
			return true
		end
	end
end

local function checkOresLEVEL1()
	look(1) --look left
	checkFront(true, false)
	look(3) --look Right
	checkFront(false, false)
	look(0) --look forward
	checkDown()
end

local function checkOresLEVEL2()
	look(1) --look left
	checkFront(true, true)
	look(3) --look Right
	checkFront(false, true)
	look(0) --look forward
	checkUp()
end

local function InventoryFull()
	SlotsFull = 0
	for i=1,16 do
		if turtle.getItemCount(i) > 0 then
			SlotsFull = SlotsFull + 1
		end
	end
	
	if SlotsFull == 16 then
		return true;
	else
		return false;
	end
end

function StartMining()

level2 = false
BlocksTillEnd = TunnelLength - PositionInBranchMine

	for i = 1,tonumber(BlocksTillEnd) do
			if Refuel() == false then
				print("***Out of fuel***")
				ReturnBack()
				return
			end
			
			if InventoryFull() then
				print("***Inventory Full***")
				ReturnBack()
				return
			end
			DigMoveForward()
	
		if level2 == false then
			checkOresLEVEL1()
			
			DigMoveUp()
			
			checkOresLEVEL2()
			
			level2 = true
			PositionInBranchMine = PositionInBranchMine + 1
			filewriteline("BranchMineData", 4, PositionInBranchMine)
			print("Position in BranchMine:",PositionInBranchMine)
		else
			checkOresLEVEL2()
			
			DigMoveDown()
			
			checkOresLEVEL1()
			
			level2 = false
			PositionInBranchMine = PositionInBranchMine + 1
			filewriteline("BranchMineData", 4, PositionInBranchMine)
			print("Position in BranchMine:",PositionInBranchMine)
		end
	end
	Finish()
end


-- Create or read data file
if fs.exists("BranchMineData") then
	readLines("BranchMineData")
	StartX = tonumber(filereadline("BranchMineData", 1))
	StartY = tonumber(filereadline("BranchMineData", 2))
	StartZ = tonumber(filereadline("BranchMineData", 3))
	PositionInBranchMine = tonumber(filereadline("BranchMineData", 4))
	RotatePosition = filereadline("BranchMineData", 5)
	print("Read Saved data. Start Position: "..StartX.." "..StartY.." "..StartZ..".")
	print("With a mine position of: "..PositionInBranchMine.." .")
	print("RotatePosition: "..RotatePosition..".")

	if UseGPS == false then
		ForwardFacingDirection = filereadline("BranchMineData", 6)
		XX = filereadline("BranchMineData", 7)
		YY = filereadline("BranchMineData", 8)
		ZZ = filereadline("BranchMineData", 9)
		if ForwardFacingDirection == "SOUTH" then
			PrimaryAxis = "Z"
			SecondaryAxis = "X"
		elseif ForwardFacingDirection == "NORTH" then
			PrimaryAxis = "-Z"
			SecondaryAxis = "-X"
		elseif ForwardFacingDirection == "EAST" then
			PrimaryAxis = "X"
			SecondaryAxis = "-Z"
		elseif ForwardFacingDirection == "WEST" then
			PrimaryAxis = "-X"
			SecondaryAxis = "Z"
		end
		print("ForwardFacingDirection: "..ForwardFacingDirection..",")
	end

	InsertedIntoLeftWall = filereadline("BranchMineData", 10)
	InsertedIntoRightWall = filereadline("BranchMineData", 11)
	InsertionAmount = filereadline("BranchMineData", 12)
	local shouldCheckUp = filereadline("BranchMineData", 13)
	if string.match(InsertedIntoLeftWall, "true") or string.match(InsertedIntoRightWall, "true")  then
		if turtle.detect() == false then
			DigMoveForward()
			InsertionAmount = InsertionAmount + 1
			if string.match(shouldCheckUp,"true") then
				shouldCheckUp = true
				checkUp()
			else
				shouldCheckUp = false
				checkDown()
			end
			checkFront(InsertedIntoLeftWall,shouldCheckUp)
		else
			if string.match(shouldCheckUp,"true") then
				shouldCheckUp = true
				checkUp()
			else
				shouldCheckUp = false
				checkDown()
			end
			checkFront(InsertedIntoLeftWall,shouldCheckUp)
		end
	end
	sleep(1)
	ReturnBack()
else
	local x, y, z = 0
	if UseGPS then
		x, y, z = gps.locate(5)
	else
		x = StartX
		y = StartY
		z = StartZ
	end

	if x == nil then
		print("Could not obtain a GPS Connection.")
		print("Please make sure you have a working GPS system.")
		return
	else
		print("Current Coords: ",x," ",y," ",z)
		StartX = x
		StartY = y
		StartZ = z
	end
	local tLines = {}
	tLines[1] = StartX
	tLines[2] = StartY
	tLines[3] = StartZ
	tLines[4] = PositionInBranchMine
	tLines[5] = RotatePosition
	if UseGPS == false then
		if string.match(ForwardFacingDirection, "SOUTH") or string.match(ForwardFacingDirection, "NORTH") or string.match(ForwardFacingDirection, "EAST") or string.match(ForwardFacingDirection, "WEST") then
		tLines[6] = ForwardFacingDirection
		XX = x
		YY = y
		ZZ = z
		tLines[7] = XX
		tLines[8] = YY
		tLines[9] = ZZ
		if ForwardFacingDirection == "SOUTH" then
			PrimaryAxis = "Z"
			SecondaryAxis = "X"
		elseif ForwardFacingDirection == "NORTH" then
			PrimaryAxis = "-Z"
			SecondaryAxis = "-X"
		elseif ForwardFacingDirection == "EAST" then
			PrimaryAxis = "X"
			SecondaryAxis = "-Z"
		elseif ForwardFacingDirection == "WEST" then
			PrimaryAxis = "-X"
			SecondaryAxis = "Z"
		end
		else
			print("ForwardFacingDirection not correctly formatted.")
			return
		end
	else
		tLines[6] = 0
		tLines[7] = 0
		tLines[8] = 0
		tLines[9] = 0
	end
	tLines[10] = InsertedIntoLeftWall
	tLines[11] = InsertedIntoRightWall
	tLines[12] = InsertionAmount
	tLines[13] = false
	writeLines("BranchMineData", tLines)
	
	-- Check fuel
local FuelCount = turtle.getItemCount(16)
	if FuelCount == 0 then
		print("please put fuel in the last slot of the Turtle.")
		return
	else
		if FuelCount < 10 then
			print("Please put at least 10 of the fuel you are using in the Turtle.")
			return
		end
	end
	Refuel()
	MineToMine()
	StartMining()
end