--This code is developed by me (onix331) and is available under the GNU General Public License (Version 3)
--For all CC-Versions Universal
--See http://opensource.org/licenses/GPL-3.0
--Have fun

space = 16--Defines the space of the turtle (If an update comes out and I don't update the program)
ver = "2.8"--For updates
status = "---"--You can modify the init-status that will be transferred to the host at the beginning

--It is usually not necessary to modify the next variables 

fw = 0--Unnecessary to know:P
chest = 0--If the turtle has stopped at a chest
stop = 0--If the turtle has stopped at a chest
shaftrun = 0--How many shafts the turtle has run
senderId = 65534--Because RedNet is a bitch:D
gravel = 3--Used to avoid gavel, sand, etc.

function startturtle()
	function smartfuel()--Check for fuel and asks for refueling
		clear()
		local fuelneeded = (length * count) * 2 + count * 3 --Calculate Fuel for mining blocks
		local movefuelneeded = ((length * count) * 2 + count) * 0.6  --Calculate Fuel for movement
		local fuelneeded = fuelneeded + movefuelneeded
		if turtle.getFuelLevel() < fuelneeded then
			insert = fuelneeded - turtle.getFuelLevel()
			print ("Current fuel-level is too low (", turtle.getFuelLevel(), ")")
			print ("Needed:" , fuelneeded)
			print ("Please insert ", insert, " fuel anywhere")
			print ("When done, press ENTER")
			debugfuel = turtle.getFuelLevel()
			while true do
				local sEvent, param = os.pullEvent("key")
				if sEvent == "key" then
					if param == 28 then
						for i = 1, space do
							for i = 1, 64 do
								clear()
								if turtle.getFuelLevel() < fuelneeded then
									shell.run("refuel")
								else
									turtle.select(1)
									break
								end
							end
							if debugfuel > turtle.getFuelLevel() then
								turtle.select(debugi)
							else
								debugi = i
								turtle.select(i)
							end
						end
						turtle.select(1)
						break
					end
				end
			end
		if turtle.getFuelLevel() < fuelneeded then
			smartfuel()
		end
		end
	end

	function pair()
		print ("Sending pairing requests")
		local i = 0
		rednet.broadcast("pair")
		os.sleep(0.1)
		rednet.broadcast("pair")
		os.sleep(0.1)
		rednet.broadcast("pair")
		os.sleep(0.1)
		rednet.broadcast("pair")
		os.sleep(0.1)
		rednet.broadcast("pair")
		os.sleep(0.1)
		rednet.broadcast("pair")
		os.sleep(0.1)
		senderId, message, protocol = rednet.receive()
		if message=="succesfull" then
			print("Succesfull paired, continuing...")
			os.sleep(0.1)
		end
	end

	function clear()--To clear the screen
		term.clear()
		term.setCursorPos(1,1)
	end

	function sendinitial()--Send the initial data
		if enablerednet=="y" then
			os.sleep(1)
			rednet.send(senderId, length)
			os.sleep(0.1)
			rednet.send(senderId, count)
			os.sleep(0.1)
			rednet.send(senderId, direction)
			os.sleep(0.1)
		end
	end

	function senddata()--To send all the data
		if enablerednet=="y" then
			rednet.send(senderId, lengthleft)
			rednet.send(senderId, count)
			rednet.send(senderId, turtle.getFuelLevel())
			rednet.send(senderId, status)
		end
	end

	function main()--Main Program
		smartfuel()
		if enablerednet=="y" then
			pair()
			sendinitial()
		end
		status = "Called main"
		senddata()
		if called==1 then
			called = 0
			countn = countn - 1
		end
		while true do
			if tonumber(count)>=1 then	
				senddata()
				fw = 1
				move()
				turnaround()
				fw = 0
				move()
				count = count - 1
				checkspace()
			else
				break
			end
		end
	end

	function returnmining()--To return to the latest shaft
		status = "Return to mine..."
		senddata()
		chest = 0
		stop = 1
		if direction=="r" then
			turtle.turnRight()
			for i = 0, shaftrun do
				turtle.forward()
				turtle.forward()
				turtle.forward()
			end
			turtle.turnLeft()
			main()
		elseif direction=="l" then
			turtle.turnLeft()
			for i = 0, shaftrun do
				turtle.forward()
				turtle.forward()
				turtle.forward()
			end
			turtle.turnRight()
			main()
		end
	end

	function checkl() --To check if length is valid (>0, not a String), also transforms the string into a number
		length = tonumber(length)
		if length==nil then
			print ("Invalid number!")
			length = read()
			checkl()
		elseif length <= 0 then
			print ("Invalid number!")
			length = read()
			checkl()
		end
	end

	function checka()--To check if count is valid (>0, not a String), also transforms the string into a number
		count = tonumber(count)
		if count==nil then
			print ("Invalid number!")
			count = read()
			checka()
		elseif count <= 0 then
			print ("Invalid number!")
			count = read()
			checka()
		end
	end

	function checkr()--To check if direction is valid ((r) or (l))
		if direction=="r" then
			print ("")
		elseif direction=="l" then
			print ("")
		else
			print ("Invalid input!")
			direction = io.read()
			checkr()
		end
	end

	function checkfue()--To check if fuel is valid (ok))
		if fuel=="ok" then
			print ("")
		else
			print ("Invalid input!")
			fuel = io.read()
			checkfue()
		end
	end

	function checkred()--To check if enablerednet is valid ((y) or (n))
		if enablerednet=="y" then
			print ("")
		elseif enablerednet=="n" then
			print ("")
		else
			print ("Invalid input!")
			enablerednet = io.read()
			checkred()
		end
	end

	function move()--Basic movement function
		status = "Moving..."
		for i = 1, length do
			senddata()
			for i = 1, gravel do
				turtle.dig()
			end
			turtle.forward()
			if fw==1 then
				lengthleft = lengthleft - 1
			end
			turtle.digDown()
			for i = 1, gravel do
				turtle.digUp()
			end
			for i = 1, gravel do
				turtle.digDown()
			end
		end
	end

	function turnaround()--Turns the turtle at 90 degrees
		status = "Turning around..."
		senddata()
		turtle.turnRight()
		turtle.turnRight()
	end

	function nextshaftr()--Next shaft (right)
		status = "Going to next shaft..."
		senddata()
		countn = countn - 1
		if countn>=2 then
			shaftrun = shaftrun + 1
			lengthleft = lengthleftstore
			turtle.turnLeft()
			turtle.dig()
			turtle.digUp()
			turtle.digDown()
			turtle.forward()
			turtle.dig()
			turtle.digUp()
			turtle.digDown()
			turtle.forward()
			senddata()
			turtle.dig()
			turtle.digUp()
			turtle.digDown()
			turtle.forward()
			turtle.digUp()
			turtle.digDown()
			turtle.turnLeft()
		end
	end

	function nextshaftl()--Next shaft (left)
		status = "Going to next shaft..."
		senddata()
		countn = countn - 1
		if countn>=2 then	
			shaftrun = shaftrun + 1
			lengthleft = lengthleftstore
			turtle.turnRight()
			turtle.dig()
			turtle.digUp()
			turtle.digDown()
			turtle.forward()
			turtle.dig()
			turtle.digUp()
			turtle.digDown()
			turtle.forward()
			senddata()
			turtle.dig()
			turtle.digUp()
			turtle.digDown()
			turtle.forward()
			turtle.digUp()
			turtle.digDown()
			turtle.turnRight()
		end
	end

	function returnpoint()--Return to initial point (Chest)
		status = "Returning to chest..."
		senddata()
		if direction=="r" then
			turtle.turnRight()
			for i = 1, shaftrun do
				turtle.forward()
				turtle.forward()
				senddata()
				turtle.forward()
			end
			if stop==1 then
				turtle.forward()
				turtle.forward()
				senddata()
				turtle.forward()
			end
			turtle.turnLeft()
			status = "Dropping things in chest..."
			senddata()
			for i = 1, space do
				turtle.select(i)
				turtle.drop()
			end
			turtle.select(1)
		elseif direction=="l" then
			turtle.turnLeft()
			for i = 1, shaftrun do
				turtle.forward()
				turtle.forward()
				senddata()
				turtle.forward()
			end
			if stop==1 then
				turtle.forward()
				turtle.forward()
				senddata()
				turtle.forward()
			end
			turtle.turnRight()
			status = "Dropping things in chest..."
			senddata()
			for i = 1, space do
				turtle.select(i)
				turtle.drop()
			end
			turtle.select(1)
		end
		turnaround()
		if chest==1 then
			returnmining()
		end
	end

	function checkspace()--Check for space and if necessary, return to initial point to the chest
		status = "Checking space"
		senddata()
		local spaceleft = 0
		for i = 1, space do
			if turtle.getItemSpace(i) > 10 then
				spaceleft = spaceleft + 1
			end
		end
		if spaceleft < 3 then
			chest = 1
			called = 1
			status = "Inventory full, returning to chest"
			returnpoint()
		elseif direction=="r" then
			nextshaftr()
		else
			nextshaftl()
		end
	end

	--Print header
	clear()
	print ("Strip-mining-program by onix331")
	print ("Version ", ver)
	os.sleep(2)

	--Start user input and define some variables
	clear()
	print ("Length of the single shaft(s):(Type help for help)")
	length = read()
	if length=="help" then
		print ("How long the shafts the turtle will mine be")
		length = read()
		checkl()
	else
		checkl()
	end
	lengthleft = length
	lengthleftstore = length

	clear()
	print ("Count of the shafts:(Type help for help)")
	count = read()
	if count=="help" then
		print ("How much shafts the turtle will mine")
		count = read()
		checka()
	else
	end
	countn = count
	countn = countn + 1

	clear()
	print ("Direction of the shafts (Left (l), Right (r):(Type help for help)")
	direction = read()
	if direction=="help" then
		print ("In which direction the shafts will go")
		direction = read()
		checkr()
	else
		checkr()
	end

	clear()
	print ("Use rednet? (Yes (y), No (n):(Type help for help)")
	enablerednet = read()
	if enablerednet=="help" then
		print ("If RedNet and a hostcomputer should be used (See my thread at http://www.computercraft.info/forums2/index.php?/topic/19835-mining-turtle-stripmining/page__fromsearch__1")
		enablerednet = read()
	else
		checkred()
		end
	if enablerednet=="y" then
		rednet.open("right")--Defines the place of the modem (Usually right on the turtle)
	end

	--Print user inputs
	clear()
	print ("Input of Length:")
	print (length)
	print ("Input of count")
	print (count)
	print ("Direction of the shafts:")
	if direction=="r" then
		print (direction, "ight")
	else
		print (direction, "eft")
	end

	print ("3")
	os.sleep(1)
	print ("2")
	os.sleep(1)
	print ("1")


	--Fire up the main program
	main()

	returnpoint()

	status = "Done!"
	senddata()--Sends the status "Done!" to the host
	print ("Done!")
end

function startcomputer()
rednet.open("right")
ver = "2.8"--For updates
status = "---"--Because i can

function clear()--To clear the screen and set the cursor to 1,1
	term.clear()
	term.setCursorPos(1,1)
end

	function receive()
		senderId, length, protocol = rednet.receive()
		storedlength = length
		senderId, count, protocol = rednet.receive()
		storedcount = count
		senderId, direction, protocol = rednet.receive()
		storeddirection = direction
			
		while true do
			clear()
			print("Length of the shaft(s): ", storedlength)
			print("Count of the shaft(s): ", storedcount)
			print("Direction of the shaft(s): ", storeddirection, "ight")
			print("Length of the shaft left: ", length)
			print("Shafts left: ", count)
			print("Fuel: ", fuel)
			print("Status: ", status)	
			if status=="Done!" then
				break
			else
				senderId, length, protocol = rednet.receive()
				senderId, count, protocol = rednet.receive()
				senderId, fuel, protocol = rednet.receive()
				senderId, status, protocol = rednet.receive()
			end
		end
	end

	function pair()
		senderId, message, protocol = rednet.receive()
		if message=="pair" then--To pair to the turtle
			for i = 1, 10 do
				rednet.send(senderId, "succesfull")
				os.sleep(0.1)
			end
			print("Succesfull paired, continuing...")
		end
		clear()
		receive()
	end


	clear()
	print ("Strip-mining-program by onix331")
	print ("Version ", ver)
	print ("Place of the modem can be modified in the program, right is recommended")
	print ("Trying to receive pair request")

	pair()

	print ("Done!")
end

if turtle then--To find out if program is run on a turtle or computer
	startturtle()
else
	startcomputer()
end