padestalManagement

local padestals
local PADESTALS_ORDER_FILE = "padestals.dat"
local m = peripheral.wrap("right")

function table.getSingleKey(tab)
	if table.size(tab) ~= 1 then error("This method expects exactly 1 key in the table, was "..#tab) end
	
	for key in pairs(tab) do
		return key
	end
end

function removeFromArray(array, object)
	if array == nil then error("Array is nil") end
	local keyToRemove
	repeat
		keyToRemove = nil
		for key, value in pairs(array) do
			if value == object then
				keyToRemove = key
				break
			end
		end
		table.remove(array, keyToRemove)
	until keyToRemove ~= nil
end

function table.size(t)
	local count = 0
	for _ in pairs(t) do
		count = count + 1
	end
	return count
end

function shallowCopy(orig)
    local orig_type = type(orig)
    local copy
    if orig_type == 'table' then
        copy = {}
        for orig_key, orig_value in pairs(orig) do
            copy[orig_key] = orig_value
        end
    else -- number, string, boolean, etc
        copy = orig
    end
    return copy
end

function table.arrayToSet(array)
	local set = {}
	for k, v in pairs(array) do
		set[v] = 1
	end
	return set
end

function listMethods(o)
	local count = 0
	for i,v in pairs(o) do
		print(i)
		count = count + 1
		if count >= 7 then
			local res = io.read()
			if res == "q" then
				return
			end
			count = 0
		end
	end

end

function listValues(o)
	local count = 0
	for i,v in pairs(o) do
		print(v)
		count = count + 1
		if count >= 7 then
			local res = io.read()
			if res == "q" then
				return
			end
			count = 0
		end
	end
end

-- nacte seznam ender chest pod padestaly
function listPadestals()
	local padestals = {}
	local peripheralSides = peripheral.getNames()
	for _, side in pairs(peripheralSides) do
		if peripheral.getType(side) == 'ender_chest' then
			table.insert(padestals, side)
		end
	end
	
	return padestals
end

function withPeripheralsDo(peripheralSides,fun)
	local collect = {}
	for _, side in pairs(peripheralSides) do
		local result = fun(side)
		if result ~= nil then 
			collect[side] = result
		end
	end
	return collect
end

function opStack_getSize(stack)
	if stack == nil then
		return 0
	end
	
	return stack.qty
end

function chestOperation_detectItemInPadestal(side) 
	--print('Processing side'..side)
	local chest = peripheral.wrap(side)
	chest.condenseItems()
	local countSlot27 = opStack_getSize(chest.getStackInSlot(27))
	if countSlot27 > 0 then
		error("Slot 27 in ender chest is not empty...")
	end
	chest.pullItem('up',1,1,27)
	countSlot27 = opStack_getSize(chest.getStackInSlot(27))
	if countSlot27 > 0 then
		return 1
	else
		return nil
	end
end

function saveTable(t,name)
	local file = fs.open(name,"w")
	file.write(textutils.serialize(t))
	file.close()
end

function loadTable(name)
	local file = fs.open(name,"r")
	local data = file.readAll()
	file.close()
	return textutils.unserialize(data)
end


function _orderPadestals()
	local notOrderedPadestals = shallowCopy(padestals)
	local limit = 5000
	local padestalOrder = {}
	while #padestalOrder < #padestals and limit > 0 do
		local padestalsWithItems = withPeripheralsDo(notOrderedPadestals,chestOperation_detectItemInPadestal)
		print("Padestals found:")
		listMethods(padestalsWithItems)
		if table.size(padestalsWithItems) > 1 then
			print("Error: Item was detected in 2 padestals at the same time. Ignoring this attempt!") 
		elseif table.size(padestalsWithItems) == 1 then
			local identifiedPadestal = table.getSingleKey(padestalsWithItems)
			table.insert(padestalOrder, identifiedPadestal)
			removeFromArray(notOrderedPadestals, identifiedPadestal)
			print("Identified "..identifiedPadestal)
		end
		limit = limit - 1
	end
	return padestalOrder
end

function initializePadestalOrder(padestals)
	local padestalOrder
	local savedPadestalsInvalid = false
	if fs.exists(PADESTALS_ORDER_FILE) then
		local loadedOrder = loadTable(PADESTALS_ORDER_FILE)
		--verify all padestals computer has are in order file and vise versa
		local computerPadestalsSet = table.arrayToSet(padestals)
		local loadedPadestalsSet = table.arrayToSet(loadedOrder)
		local computerPadestalsNotInLoaded = false
		local loadedPadestalsNotInComputer = false
		for key in pairs(computerPadestalsSet) do
			if loadedPadestalsSet[key] == nil then
				computerPadestalsNotInLoaded = true
			end
		end
		for key in pairs(loadedPadestalsSet) do
			if computerPadestalsSet[key] == nil then
				loadedPadestalsNotInComputer = true
			end
		end
		
		if computerPadestalsNotInLoaded or loadedPadestalsNotInComputer then
			padestalOrder = nil
			savedPadestalsInvalid = true
		else
			padestalOrder = loadedOrder
		end
	end
	
	if padestalOrder == nil then
		if savedPadestalsInvalid then
			print("Warning: padestals saved in the file are no longer matching padestals of the computer. Reinitialization needed.")
		end
		print("Padestal order initialization - put dirt onto padestals in order, which will imply symetry of padestals. This order will be stored in computer and will be loaded next time. Before putting next item onto padestal wait for previous item to disappear")
		padestalOrder = _orderPadestals()
		saveTable(padestalOrder, PADESTALS_ORDER_FILE)
	end
end

padestals = listPadestals()
padestalOrder = initializePadestalOrder(padestals)