-- ********************************************************************************** --

-- **                                                                              ** --

-- **   Minecraft AE2 Auto-Stocker by RandomBlue (E.J. Wilburn)                    ** --

-- **   ----------------------------------------------------                       ** --

-- **                                                                              ** --

-- **   This program automatically crafts items necessary to maintain a minimum    ** --

-- **   stock level of specific items.  The items are configured in a file on      ** --

-- **   a computercraft computer named stock_list.txt in the stocker directory.    ** --

-- **   Examine that file for example formatting and details.                      ** --

-- **                                                                              ** --

-- **   Minimum stock levels and crafting batch sizes are configurable per item.   ** --

-- **                                                                              ** --

-- **   The computer must be placed adjacent to a full block ME Interface attached ** --

-- **   to an ME Network where both the items are stored and the crafting CPUs are ** --

-- **   located.  Each item you wish to maintain a stock level for must have       ** --

-- **   autocrafting enabled for it.                                               ** --

-- **                                                                              ** --

-- **   Arguments                                                                  ** --

-- **   ----------------------------------------------------                       ** --

-- **   checkFrequency (optional) - How often inventory levels are checked in      ** --

-- **                               seconds.                                       ** --

-- **   attachSide (optional)     - Side the computer is attached to the           ** --

-- **                               ME Interface (full block version).             ** --

-- **   stockFileName (optional)  - Full path to the file containing stocking      ** --

-- **                               requirements.                                  ** --

-- **                                                                              ** --

-- **  Change Log:                                                                 ** --

-- **    8th Sep 2015:  [v0.1]  Initial Release                                    ** --

-- **    11th Sep 2015: [v0.11] Minor bug fix - attempting to crafting 0 items     ** --

-- **                           when current quantity equals minQuantity           ** --

-- **                                                                              ** --

-- **  TODO:                                                                       ** --

-- **    1) Save command line parameters to startup script.                        ** --

-- **                                                                              ** --

-- ********************************************************************************** --

-- Parameters with default values.

local checkFrequency = 15 -- How often inventory levels are checked in seconds.  Overridden by passing as the first argument.

local attachSide = "bottom" -- Side the computer is attached to the ME Interface (full block version).

                            -- Overridden by passing as the second argument.

local stockFileName = "stocker/stock_list.txt" -- Change this if you want the file somewhere else.  Can be

                                               -- overridden via a parameter.

local recraftDelay = 300 -- Delay, in seconds, before allowing an item to be crafted again.  If them item in question exceeds

                         -- its min quantity before the delay expires, the delay is reset as it's assumed the job

                         -- completed.  300 seconds = 5 minutes

local delayedItems = {} -- List of delayed items by id:variant with delay time in seconds.  Decremented each loop by

                        -- checkFrequency ammount.  When the delay hits 0 or lower then the item is removed from

                        -- the list.

local DEBUG = false

-- Process the input arguments - storing them to global variables

local args = { ... }

function main(args)

	processArgs(args)

	local ae2 = attachToAe2(attachSide)

	local stocks = loadStockFile(stockFileName)

	displayStockingInfo(stocks)

	enableAutoRestart()

	while (true) do

		print("[" .. getDisplayTime() .. "] Checking inventory.")

		updateDelayedItems(delayedItems)

		local allItems = getAllItems(ae2)

		for i=1, #allItems do

			if (allItems[i].is_craftable == true) then

				stockItem(allItems[i], stocks, ae2)

			end

		end

		os.sleep(checkFrequency)

	end

end

function isValidSide(side)

	if (side == "left" or side == "right" or side == "top" or side == "bottom" or side == "front" or side == "back") then

		return true

	else

		return false

	end

end

function processArgs(args)

	if (#args >= 1) then

		assert(type(args[1]) == "number", "The first parameter (checkFrequency) must be a number.")

		checkFrequency = args[1]

	end

	if (#args > 1) then

		assert(type(args[2]) == "string", "The second parameter (attachSide) must be a string.")

		attachSide = args[2]:lower()

	end

	assert(isValidSide(attachSide),	"The attachSide parameter must be a valid side: left, right, front, back, top, bottom")

	if (#args > 2) then

		assert(type(args[3]) == "string", "The third parameter (stockFileName) must be a string.")

		stockFileName = args[3]

	end

	assert(fs.exists(stockFileName), "The stock file does not exist: " .. stockFileName)

end

function attachToAe2(attachSide)

	-- Make sure the attached device is actually an ME Interface.

	assert(peripheral.getType(attachSide) == "tileinterface", "The computer must be attached to a full block " ..

		"ME Inteface on the specified side.")

	return peripheral.wrap(attachSide)

end

function loadStockFile(stockFileName)

	local stockFile = fs.open(stockFileName, "r")

	local stockFileContents = stockFile.readAll();

	stockFile.close();

	local outputStocks = textutils.unserialize(stockFileContents)

	if (DEBUG) then

		print("Stock file: ")

		print(stockFileContents)

		print("Output stocks length: " .. #outputStocks)

		print("Output stocks: ")

		for i=1, #outputStocks do

			print("itemId: " .. outputStocks[i].itemId)

			print("variant: " .. outputStocks[i].variant)

			print("minQuantity: " .. outputStocks[i].minQuantity)

			print("batchSize: " .. outputStocks[i].batchSize)

		end

	end

	assert(#outputStocks > 0, "There are no entries in the " .. stockFileName .. " file.")

	return outputStocks

end

function displayStockingInfo(stocks)

	print("Stocking info:")

	for i=1, #stocks do

		print(" itemId: " .. stocks[i].itemId .. ":" .. stocks[i].variant .. " minQuantity: " .. stocks[i].minQuantity ..

			" batchSize: " .. stocks[i].batchSize)

	end

end

function getAllItems(ae2)

	local outputAllItems = ae2.getAvailableItems()

	assert(outputAllItems ~= nil, "No craftable items found in this AE2 network.")

	assert(#outputAllItems > 0, "No craftable items found in this AE2 network.")

	return outputAllItems

end

function isCpuAvailable(ae2)

	local cpus = ae2.getCraftingCPUs()

	for i=1, #cpus do

		if (cpus[i].busy == false) then return true end

	end

	return false

end

function findStockSetting(fingerprint, stocks)

	for i=1, #stocks do

		if (stocks[i].itemId == fingerprint.id and stocks[i].variant == fingerprint.dmg) then

			return stocks[i]

		end

	end

	return nil

end

function stockItem(currItem, stocks, ae2)

	local stockSetting = findStockSetting(currItem.fingerprint, stocks)

	if (stockSetting == nil or currItem.size >= stockSetting.minQuantity or isDelayed(currItem.fingerprint, delayedItems)

	    or isCpuAvailable(ae2) == false) then return end

	local neededAmount = math.ceil((stockSetting.minQuantity - currItem.size) / stockSetting.batchSize) * stockSetting.batchSize

	ae2.requestCrafting(currItem.fingerprint, neededAmount)

	delayItem(currItem.fingerprint, delayedItems)

	print("[" .. getDisplayTime() .. "] Item " .. stockSetting.displayName ..

		" is below its min stock level of " .. stockSetting.minQuantity .. ".  Crafting " .. neededAmount .. " more.")

end

function getDisplayTime()

	return textutils.formatTime(os.time(), false)

end

function delayItem(fingerprint, delayedItems)

	local fullItemName = fingerprintToFullName(fingerprint)

	if(delayedItems == nil) then

		delayedItems = {}

	end

	for i=1, #delayedItems do

		if (delayedItems[i].fullName == fullItemName) then

			delayedItems[i].delay = recraftDelay

			return

		end

	end

	local delayedItem = {fullName = fullItemName, delay = recraftDelay}

	delayedItems[#delayedItems+1] = delayedItem

end

function updateDelayedItems(delayedItems)

	if (delayedItems == nil or #delayedItems < 1) then return end

	local removeIndexes = {}

	for i=1, #delayedItems do

		currItem = delayedItems[i]

		currItem.delay = currItem.delay - checkFrequency

		if (currItem.delay < 0) then

			table.insert(removeIndexes, i)

		end

	end

	-- This should remove items from the end of the list towards the beginning

	-- so the list being reordered won't matter.

	for i=1, #removeIndexes do

		table.remove(delayedItems, removeIndexes[i])

	end

end

function fingerprintToFullName(fingerprint)

	return fingerprint.id .. ":" .. fingerprint.dmg

end

function isDelayed(fingerprint, delayedItems)

	if (delayedItems == nil or #delayedItems < 1) then return false end

	local fullItemName = fingerprintToFullName(fingerprint)

	for i=1, #delayedItems do

		if (delayedItems[i].fullName == fullItemName and delayedItems[i].delay > 0) then

			return true

		end

	end

	return false

end

function enableAutoRestart()

	-- Skip this if any startup file already exists.

	-- Let the user manaully delete or edit the startup file at that point.

	-- Notify the user.

	if (fs.exists("startup") == true) then

		print("Startup file already exists.")

		return

	end

	outputFile = fs.open("startup", "w")

	-- Write an info message so that people know how to get out of auto-resume

	outputFile.write("\nprint(\"Running auto-restart...\")\n")

	outputFile.write("print(\"If you want to stop auto-resume and restore original state:\")\n")

	outputFile.write("print(\"1) Hold Ctrl-T until the program terminates\")\n")

	outputFile.write("print(\"2) Type \\\"rm startup\\\" (without quotes) and hit Enter\")\n")

	outputFile.write("print(\"\")\n\n")

	-- Write the code required to restart the turtle

	outputFile.write("shell.run(\"")

	outputFile.write(shell.getRunningProgram())

	outputFile.write("\")\n")

	outputFile.close()

end

-- Start the actual program

main(args)