text_utils.lua

local utils = {}

function utils.replaceArgs(text, args)
	for k, v in pairs(args) do
		text = text:gsub("%$" .. tostring(k) .. "%$", tostring(v))
	end
	return text
end

-- Jaro-Winkler distance algorithm
function utils.distance(s1, s2)
	local math_max, math_min = math.max, math.min
	if s1 == s2 then
		return 1.0
	end

	local s1len, s2len = #s1, #s2

	if s1len == 0 or s2len == 0 then
		return 0.0
	end

	local maxDist = math.floor(math_max(s1len, s2len) / 2) - 1
	local hashS1, hashS2 = {}, {}
	local matches, transpositions = 0, 0

	for i = 1, s1len do
		local start = math_max(1, i - maxDist)
		local stop = math_min(s2len, i + maxDist)
		for j = start, stop do
			if not hashS2[j] and s1:sub(i, i) == s2:sub(j, j) then
				hashS1[i], hashS2[j] = true, true
				matches = matches + 1
				break
			end
		end
	end

	if matches == 0 then
		return 0.0
	end

	local k = 1

	for i = 1, s1len do
		if hashS1[i] then
			while not hashS2[k] do
				k = k + 1
			end
			if s1:sub(i, i) ~= s2:sub(k, k) then
				transpositions = transpositions + 1
			end
			k = k + 1
		end
	end

	local jaroSim = (matches / s1len + matches / s2len + (matches - transpositions / 2) / matches) / 3
	local weight = 0.1
	local prefixLen = 0

	for i = 1, math_min(s1len, s2len, 4) do
		if s1:sub(i, i) == s2:sub(i, i) then
			prefixLen = prefixLen + 1
		else
			break
		end
	end

	return jaroSim + (prefixLen * weight * (1 - jaroSim))
end

return utils