local fileFilters = {
	["model/vehicle"] = { },
	["model/person"] = { },
	["model/car"] = { },
	["model/rock"] = { },
	["model/tree"] = { },
	["model/signal"] = { },
	["model/other"] = { },

	multipleUnit = { },
	street = { },
	track = { },
	bridge = { },
	tunnel = { },
	railroadCrossing = { },
	trafficLight = { },
	environment = { },
	construction = { },
	["module"] = {},
	autoGroundTex = { },
	groundTex = { },
	terrainGenerator = { },
	terrainMaterial = { },
	cargoType = { },
	grass = { },
	gameScript = { },
	climate = { },
}

function addFileFilter(cat, fn)
	local ff = fileFilters[cat]
	ff[#ff + 1] = fn
end

function clearFileFilter(cat)
	fileFilters[cat] = {}
end

function applyFileFilters(cat, fileName, data)
	local function filter(filters, fileName, data)
		for i, fn in ipairs(filters) do
			if not fn(fileName, data) then
				return nil
			end
		end

		return data
	end

	if string.ends(cat, "/") then
		for k, v in pairs(fileFilters) do
			if string.starts(k, cat) then
				local result = filter(v, fileName, data)
				if result then
					return result
				end
			end
		end

		return nil
	end

	return filter(fileFilters[cat], fileName, data)
end



local modifiers = {
	loadModel = { },
	loadModule = { },
	loadMultipleUnit = { },
	loadStreet = { },
	loadTrack = { },
	loadBridge = { },
	loadTunnel = { },
	loadRailroadCrossing = { },
	loadTrafficLight = { },
	loadEnvironment = { },
	loadConstruction = { },
	loadConstructionCategory = { },
	loadConstructionMenu = { },
	loadSoundSet = { },
	loadScript = { },
	loadTerrainMaterial = { },
	loadGrass = { },
	loadGameScript = { },
	loadGroundTex = { },
	loadTerrainGenerator = { },
	loadClimate = { },
	loadCargoType = { },
}

function addModifier(key, fun)
	table.insert(modifiers[key], fun)
end

function applyModifiers(key, name, data)
	for i, v in ipairs(modifiers[key]) do
		data = v(name, data)
	end

	return data
end



local i18n = { }

function setStrings(mod, strings)
	i18n[mod] = {
		strings = strings
	}
end

function translateModStr(modId, locale, id)
	--print("translate: ", id, " to ", locale, "\n")

	if not i18n[modId] then
		return id
	end

	local strings = i18n[modId].strings

	if strings[locale] then
		local result = strings[locale][id]
		if result then return result end
	end
	
	if locale:len() > 2 then
		local shortLocale = string.sub(locale, 1, 2)
		--print("  shortLocale: ", shortLocale, "\n")
		if strings[shortLocale] then
			local result = strings[shortLocale][id]
			if result then return result end
		end
	end
	
	if locale ~= "en" then
		if strings["en"] then
			local result = strings["en"][id]
			if result then return result end
		end
	end
	
	return id
end

function _(id)
	if id == nil or _locale:len() == 0  then
		return id
	end
	if _currentModIdTr ~= nil then
		local txt = translateModStr(_currentModIdTr, _locale, id)
		if txt ~= id then
			return txt
		end
	end
	if _getTextNow then
		return getTextRes(id)
	end
	return id
end
-- relozu_find_modifiers_and_filefilters_script
local rReduceErrorMessagesToMinimum = true

local rErrMessages = { }

local rModifierFns   = table.copy(modifiers)
local rFileFilterFns = table.copy(fileFilters)

local rLuaTypes = {
	typeString  = type(""),
	typeNil     = type(nil),
	typeTable   = type({ }),
	typeBoolean = type(true),
}

local rFnType = {
	modifier   = 0,
	fileFilter = 1,
}

local rErrType = {
	errDefault = 0,
	errReturn  = 1,
}

local rUnknownMod    = "unknown mod"
local rUnknownFile   = "unknown file"
local rUnknownError  = "unknown error"
local rPrefix        = "[relozu_find_modifiers_and_filefilters] "
local rDirSeparator  = "/"
local rQuotationMark = "\""

local rErrorFileFilterDefault = "Error in a fileFilter function: Mod: "
local rErrorModifierDefault   = "Error in a modifier function: Mod: "
local rErrorFileFilterReturn  = "Get back wrong value type from a fileFilter function: Mod: "
local rErrorModifierReturn    = "Get back wrong value type from a modifier function: Mod: "

local rGetType          = ", Get value type: "
local rExpectedTypeText = ", Expected value type: "
local rHandledFile      = ", Handled file: "
local rErrorMsg         = ", Error message: "
local rModifierType     = ", Modifier type: "
local rFileFilterType   = ", FileFilter type: "

-- relozu_find_modifiers_and_filefilters function
local function getErrorStrings(t, name, fn)
	local modCurrent = nil
	
	for i = 1, #t, 1 do
		if t[i].fn == fn then
			modCurrent = t[i].mod
			break
		end
	end
	
	if type(t)          ~= rLuaTypes.typeTable  then t = { }                  end
	if type(modCurrent) ~= rLuaTypes.typeString then modCurrent = rUnknownMod end
	if type(name)       ~= rLuaTypes.typeString then name = rUnknownFile      end

	return modCurrent, name
end

-- relozu_find_modifiers_and_filefilters function
local function printErrorMessage(fn, fnType, key, fileName, val, errType)
	local modCurrent, errorTypeText, expectedType, fnTypeText, errMessageKey, printMiddlePart

	if fnType == rFnType.fileFilter then
		modCurrent, fileName = getErrorStrings(rFileFilterFns[key], fileName, fn)
		expectedType         = rLuaTypes.typeBoolean
		fnTypeText           = rFileFilterType
		
		if errType == rErrType.errReturn then
			errorTypeText = rErrorFileFilterReturn
		else
			errorTypeText = rErrorFileFilterDefault
		end
	else
		modCurrent, fileName = getErrorStrings(rModifierFns[key], fileName, fn)
		expectedType         = rLuaTypes.typeTable
		fnTypeText           = rModifierType
		
		if errType == rErrType.errReturn then
			errorTypeText = rErrorModifierReturn
		else
			errorTypeText = rErrorModifierDefault
		end
	end

	if errType == rErrType.errReturn then
		errMessageKey = errorTypeText .. modCurrent .. key .. val .. expectedType
	else
		if type(val) ~= rLuaTypes.typeString then val = rUnknownError end

		if rReduceErrorMessagesToMinimum then
			errMessageKey = errorTypeText .. modCurrent .. key
		else
			errMessageKey = errorTypeText .. modCurrent .. key .. val
		end
	end
	
	if type(rErrMessages[errMessageKey]) == rLuaTypes.typeNil then
		rErrMessages[errMessageKey] = 1

		if errType == rErrType.errReturn then		
			printMiddlePart = rGetType .. rQuotationMark .. val .. rQuotationMark .. rExpectedTypeText .. rQuotationMark .. expectedType .. rQuotationMark
		else
			printMiddlePart = rErrorMsg .. rQuotationMark .. val .. rQuotationMark
		end
		
		print(rPrefix .. errorTypeText .. rQuotationMark .. modCurrent .. rQuotationMark .. fnTypeText .. rQuotationMark .. key .. rQuotationMark .. printMiddlePart .. rHandledFile .. rQuotationMark .. fileName .. rQuotationMark)
	end
end

-- relozu_find_modifiers_and_filefilters function
addFileFilter = function(cat, fn)
	table.insert(fileFilters[cat], fn)
	table.insert(rFileFilterFns[cat], { mod = getCurrentModId(), fn = fn })
end

-- relozu_find_modifiers_and_filefilters function
clearFileFilter = function(cat)
	fileFilters[cat] = { }
	rFileFilterFns[cat] = { }
end

-- relozu_find_modifiers_and_filefilters function
applyFileFilters = function(cat, fileName, data)
	local function filter(filters, fileName, data)
		local worked, modCurrent, val

		for i, fn in ipairs(filters) do
			worked, val = pcall(fn, fileName, data)

			if not worked then
				printErrorMessage(fn, rFnType.fileFilter, cat, fileName, val, rErrType.errDefault)
			else
				if type(val) == rLuaTypes.typeBoolean then
					if not val then return nil end
				else
					printErrorMessage(fn, rFnType.fileFilter, cat, fileName, type(val), rErrType.errReturn)
				end
			end
		end

		return data
	end

	if string.ends(cat, rDirSeparator) then
		for k, v in pairs(fileFilters) do
			if string.starts(k, cat) then
				local result = filter(v, fileName, data)

				if result then
					return result
				end
			end
		end

		return nil
	end

	return filter(fileFilters[cat], fileName, data)
end

-- relozu_find_modifiers_and_filefilters function
addModifier = function(key, fun)
	table.insert(modifiers[key], fun)
	table.insert(rModifierFns[key], { mod = getCurrentModId(), fn = fun })
end

-- relozu_find_modifiers_and_filefilters function
applyModifiers = function(key, name, data)
	local worked, modCurrent, val

	for k, fn in ipairs(modifiers[key]) do
		worked, val = pcall(fn, name, data)

		if not worked then
			printErrorMessage(fn, rFnType.modifier, key, name, val, rErrType.errDefault)
		else
			if type(val) == rLuaTypes.typeTable then
				data = val
			else
				printErrorMessage(fn, rFnType.modifier, key, name, type(val), rErrType.errReturn)
			end
		end
	end

	return data
end