Documentation for this module may be created at Module:syl-translit/doc

-- Transliteration for Sylheti in Sylheti Nagri script

local export = {}
local gsub = mw.ustring.gsub
local match = mw.ustring.match
 
local conv = {
	-- consonants
	['ꠇ'] = 'x',	['ꠈ'] = 'x',	['ꠉ'] = 'g',	['ꠊ'] = 'g',
	['ꠌ'] = 's',	['ꠍ'] = 's',	['ꠎ'] = 'z',	['ꠏ'] = 'z',
	['ꠐ'] = 'ṭ',	['ꠑ'] = 'ṭ',	['ꠒ'] = 'ḍ',	['ꠓ'] = 'ḍ',
	['ꠔ'] = 't',	['ꠕ'] = 't',	['ꠖ'] = 'd',	['ꠗ'] = 'd',	['ꠘ'] = 'n',
	['ꠙ'] = 'f',	['ꠚ'] = 'f',	['ꠛ'] = 'b',	['ꠜ'] = 'b',	['ꠝ'] = 'm',
	['ꠞ'] = 'r',	['ꠟ'] = 'l',	['ꠠ'] = 'ṛ', 
	['ꠡ'] = 'ś',    ['ꠢ'] = 'h', ['ꠋ'] = 'ng', 

	-- vowel diacritics
	['ꠣ'] = 'a', ['ꠤ'] = 'i',	['ꠥ'] = 'u', ['ꠦ'] = 'e', ['ꠧ'] = 'o',

	-- vowel signs
	['ꠀ'] = 'a', ['ꠁ'] = 'i', ['ꠃ'] = 'u', ['ꠄ'] = 'e', ['ꠅ'] = 'o',

	-- virama
	['꠆'] = '',
		
	-- anusvar
	[' ꠋ'] = 'ṅ',

	-- dvisvara
	['ꠂ'] = 'i',

	-- numerals
	['০'] = '0', ['১'] = '1', ['২'] = '2', ['৩'] = '3', ['৪'] = '4', ['৫'] = '5', ['৬'] = '6', ['৭'] = '7', ['৮'] = '8', ['৯'] = '9',
 
	-- punctuation
	['꠪'] = '.', -- dari/purn virama
	['꠫'] = '.'
}

local consonant, vowel, vowel_sign = "ꠇ-ꠊꠌ-ꠢ", "ꠣ-ꠧ", "ꠀꠁꠃ-ꠅ"
local c = "[" .. consonant .. "]"
local v = "[" .. vowel .. vowel_sign .. "]"
local syncope_pattern = "(" .. v .. c .. v .. c .. ")ô(" .. c .. "ঁ?" .. v .. ")"

local function rev_string(text)
	local result, length = "", mw.ustring.len(text)
	for i = 1, length do
		result = result .. mw.ustring.sub(text, -i, -i)
	end
	return result
end

function export.tr(text, lang, sc)
	-- from [[MOD:as-translit]]
	text = gsub(text, "(" .. c .. ")([" .. vowel .. "’?꠆]?)", function(a, b)
		return a .. (b == "" and "ô" or b) end)
	
	for word in mw.ustring.gmatch(text, "[ꠀ-ꠧô’]+") do
		local orig_word = word
		word = rev_string(word)
		word = gsub(word, "^ô(" .. c .. ")(" .. v .. ")", "%1%2")
		while match(word, syncope_pattern) do
			word = gsub(word, syncope_pattern, "%1%2")
		end
		text = gsub(text, orig_word, rev_string(word))
	end
	
	text = gsub(text, ".", conv)

	-- ô is really just o
	text = mw.ustring.gsub(text, 'ô', 'o')
	
	-- velars
	text = mw.ustring.gsub(text, 'x([iu])', 'k%1')
	text = mw.ustring.gsub(text, '([iu])x', '%1k')
	text = mw.ustring.gsub(text, 'xx', 'kk')
	
	-- palatals (I think?)
	text = mw.ustring.gsub(text, 'ss', 'cc')
	
	-- affricates (I'm just guessing now)
	text = mw.ustring.gsub(text, 'jj', 'zz')
	text = mw.ustring.gsub(text, 'zs', 'jc')
	
	-- final r/l
	text = mw.ustring.gsub(text, '([xrl])o$', '%1')
	text = mw.ustring.gsub(text, '([xrl])o ', '%1 ')
	
	return text
end
 
return export