require("pathfinding")
pretty = require("cc.pretty")
pp = pretty.pretty_print()

isFluid = {
	water = true,
	lava = true,
	milk = true,
	blood = true,
	molten_rose_gold = true,
	molten_copper = true,
	molten_gold = true,
	molten_bronze = true,
	molten_tin = true,
	molten_zinc = true,
	compound_mixture = true,
}

fluidDevicePos = {
	trash = vector.new(2, 0, -1),
	water_source = vector.new(0, 0, -1),
	mixer = vector.new(-1, 0, -1),
	compactor = vector.new(-2, 0, -1),
	spout = vector.new(-3, 0, -1),
	melter = vector.new(-4, 0, -1),
}

tankPos = {
	vector.new(4, 0, -3),
	vector.new(3, 0, -3),
	vector.new(2, 0, -3),
	vector.new(1, 0, -3),
	vector.new(0, 0, -3),
	vector.new(-1, 0, -3),
	vector.new(-2, 0, -3),
	vector.new(-3, 0, -3),
	vector.new(-4, 0, -3),
}

function setRedRouter(state)
	peripheral.call("bottom", "setOutput", "bottom", state)
	peripheral.call("bottom", "setOutput", "front", state)
end

function loadFluidInventory()
	return require("fluid_state")
end

function saveFluids()
	fs.delete("fluid_state.lua")
	repeat
		file = fs.open("fluid_state.lua", "w")
	until file
	file.write("return ")
	file.write(textutils.serialise(_G.fluidTanks))
	file.close()
end

function getFluidAmount(type)
	for index, tank in pairs(_G.fluidTanks) do
		if tank.name == type then
			return tank.amount
		end
	end
	return 0
end

function pumpToDevices(enable)
	goTo(vector.new(4, 0, -1))
	-- clutches invert the signal
	setRedRouter(not enable)
end

function pumpToTanks(enable)
	goTo(vector.new(3, 0, -1))
	-- clutches invert the signal
	setRedRouter(not enable)
end

function resetAllFluidDevices()
	pumpToDevices(false)
	pumpToTanks(false)
	-- for name, pos in pairs(fluidDevicePos) do
	-- 	goTo(pos)
	-- 	setRedRouter(false)
	-- end
	for x = 2, -4, -1 do
		goTo(vector.new(x, 0, -1))
		setRedRouter(false)
	end
	for x = -4, 4 do
		goTo(vector.new(x, 0, -3))
		setRedRouter(false)
	end
	_G.activeFluidDevice = nil
	for i = 1, 9 do
		_G.fluidTanks[i].connected = false
	end
end

function selectFluidDevice(name)
	if fluidDevicePos[name] == nil then
		error("selectFluidDevice(" .. name .. "); not a known fluid device", 2)
	end

	if _G.activeFluidDevice ~= nil then
		goTo(fluidDevicePos[_G.activeFluidDevice])
		_G.activeFluidDevice = nil
		setRedRouter(false)
	end
	goTo(fluidDevicePos[name])
	setRedRouter(true)
	_G.activeFluidDevice = name
end

function connectTankOrAssign(fluid)
	local has_fluid = false
	for index, tank in pairs(_G.fluidTanks) do
		if tank.name == fluid then
			has_fluid = true
			print(fluid, "already assigned to", index)
		end
	end
	if not has_fluid then
		print(fluid, "not in tanks, assigning new")
		for index = 1, 9 do
			if _G.fluidTanks[index].name == nil or _G.fluidTanks[index].amount == 0 then
				_G.fluidTanks[index] = {
					name = fluid,
					amount = 0,
					connected = false
				}
				print("assigned tank", index, "to", fluid)
				break
			end
		end
	end
	connectTanks({ fluid })
end

function connectTanks(fluid_list)
	print("connecting tanks")
	pp(fluid_list)
	for index, tank in pairs(_G.fluidTanks) do
		should_be_connected = false
		for _, fluid in pairs(fluid_list) do
			if tank.name == fluid then
				should_be_connected = true
				break
			end
		end
		if should_be_connected ~= tank.connected then
			print("setting", tank.name, index, "to", should_be_connected)
			goTo(tankPos[index])
			setRedRouter(should_be_connected)
			_G.fluidTanks[index].connected = should_be_connected
		end
	end
end

function fluidInvAdd(name, amount)
	print("added", amount, "to", name)
	for index, tank in pairs(_G.fluidTanks) do
		if tank.name == name then
			tank.amount = tank.amount + amount
			-- TODO limit capacity
		end
	end
	saveFluids()
end

_G.fluidTanks = _G.fluidTanks or loadFluidInventory()