Modul:lo-translit

local export = {}
local gsub = mw.ustring.gsub
local len = mw.ustring.len
local match = mw.ustring.match
local sub = mw.ustring.sub

local initial_conv = {
	["ກ"] = "k", ["ຂ"] = "kh", ["ຄ"] = "kh", ["ງ"] = "ng", 
	["ຈ"] = "ch", ["ສ"] = "s", ["ຊ"] = "s", ["ຍ"] = "ny", 
	["ດ"] = "d", ["ຕ"] = "t", ["ຖ"] = "th", ["ທ"] = "th", ["ນ"] = "n", 
	["ບ"] = "b", ["ປ"] = "p", ["ຜ"] = "ph", ["ຝ"] = "f", ["ພ"] = "ph", ["ຟ"] = "f", ["ມ"] = "m", 
	["ຢ"] = "y", ["ຣ"] = "r", ["ລ"] = "l", ["ວ"] = "w",
	["ຫ"] = "h", ["ອ"] = "ʼ", ["ຮ"] = "h",
	
	["ຫງ"] = "ng",
	["ຫຍ"] = "ny",
	["ໜ"] = "n", ["ຫນ"] = "n", 
	["ໝ"] = "m", ["ຫມ"] = "m",
	["ຫຼ"] = "r", ["ຫຣ"] = "r",
	["ຫຼ"] = "l", ["ຫລ"] = "l",
	["ຫວ"] = "w"
}

local vowel_conv = {
	["ະ"] = "a", ["ັ"] = "a", 
	["ິ"] = "i", 
	["ຶ"] = "ư", ["ຸ"] = "u", 
	["ເະ"] = "e", ["ເັ"] = "e", 
	["ແະ"] = "æ", ["ແັ"] = "æ", 
	["ໂະ"] = "o", ["ົ"] = "o", 
	["ເາະ"] = "ǫ", ["ັອ"] = "ǫ", 
	["ເິ"] = "œ", 
	["ເັຍ"] = "ia", ["ັຽ"] = "ia", 
	["ເຶອ"] = "ưa", 
	["ົວະ"] = "ua", ["ັວ"] = "ua", ["ວັ"] = "ua",
	["ໄ"] = "ai", ["ໃ"] = "ai", ["ັຍ"] = "ai", 
	["ເົາ"] = "ao", 
	["ົາວ"] = "uau",
	["ຳ"] = "am", ["ໍາ"] = "am", 
	["ວຳ"] = "uam",
	
	["າ"] = "ā", 
	["າວ"] = "āo", 
	["ີ"] = "ī", 
	["ື"] = "ư̄", 
	["ູ"] = "ū", 
	["ເ"] = "ē", 
	["ແ"] = "ǣ", 
	["ໂ"] = "ō", 
	["ໂຍ"] = "ōi", ["ໂຽ"] = "ōi",
	["ໍ"] = "ǭ", ["ອ"] = "ǭ", 
	["ອຍ"] = "ǭi", ["ອຽ"] = "ǭi",
	["ເີ"] = "œ̄", 
	["ເີຽ"] = "œ̄i", ["ເີຍ"] = "œ̄i",
	["ເຍ"] = "īa", ["ເັຽ"] = "īa", ["ຽ"] = "īa", 
	["ເືອ"] = "ư̄a", 
	["ົວ"] = "ūa", ["ວ"] = "ūa", 
	["ວຍ"] = "uāi", ["ວຽ"] = "uāi", ["ວຽນ"] = "uīan",
	["າຍ"] = "āi", ["າຽ"] = "āi",
	["ວາ"] = "uā",
	["ວາຍ"] = "uāi", ["ວາຽ"] = "uāi",
	["ແວ"] = "ǣu", -- ແ_ວ can bo both ǣu and uǣ. The first is more common.
	["ີວ"] = "īu", ["ິວ"] = "iu",
	["ຽວ"] = "iāu",
	["ວີວ"] = "uīu",
}

local coda_conv = {
	["ກ"] = "k", ["ຂ"] = "k", ["ຄ"] = "k", 
	["ງ"] = "ng", 
	["ຈ"] = "t", ["ສ"] = "t", ["ຊ"] = "t", 
	["ຍ"] = "ny", 
	["ດ"] = "t", ["ຕ"] = "t", ["ຖ"] = "t", ["ທ"] = "t", 
	["ນ"] = "n", 
	["ບ"] = "p", ["ປ"] = "p", ["ຜ"] = "p", ["ຝ"] = "p", ["ພ"] = "p", ["ຟ"] = "p", 
	["ມ"] = "m", 
	["ຢ"] = "y", 
	["ຣ"] = "n", ["ລ"] = "n", 
	["ວ"] = "w",
	[""] = "",
}

local sp_symbols = {
	["ຯ"] = "〃", ["ໆ"] = "〃",
	["໌"] = "",
	["໐"] = "0", ["໑"] = "1", ["໒"] = "2", ["໓"] = "3", ["໔"] = "4",
	["໕"] = "5", ["໖"] = "6", ["໗"] = "7", ["໘"] = "8", ["໙"] = "9"
}

local char_type = {
	['ກ'] = 'coda',	['ຂ'] = 'coda',	['ຄ'] = 'coda',	['ງ'] = 'coda',
	['ຈ'] = 'coda',	['ຊ'] = 'coda',	['ຍ'] = 'ambig',
	['ດ'] = 'coda',	['ຕ'] = 'coda',	['ຖ'] = 'coda',	['ທ'] = 'coda',	['ນ'] = 'coda',
	['ບ'] = 'coda',	['ປ'] = 'coda',	['ຜ'] = 'coda',	['ຝ'] = 'coda',	['ພ'] = 'coda',	['ຟ'] = 'coda',	['ມ'] = 'coda',
	['ຢ'] = 'coda',	['ຣ'] = 'coda',	['ລ'] = 'coda',	['ວ'] = 'ambig',
	['ສ'] = 'coda',	['ຫ'] = 'cons',	['ອ'] = 'ambig', ['ຮ'] = 'cons',
	['ຯ'] = 'iter_symbol',
	['ະ'] = 'vowel_let', ['ັ'] = 'suf_vowel', ['າ'] = 'vowel_let', ['ຳ'] = 'suf_vowel',
	['ິ'] = 'suf_vowel', ['ີ'] = 'suf_vowel', ['ຶ'] = 'suf_vowel', ['ື'] = 'suf_vowel',
	['ຸ'] = 'suf_vowel', ['ູ'] = 'suf_vowel', ['ົ'] = 'suf_vowel',
	['ຼ'] = 'cons',
	['ຽ'] = 'vowel_let',
	['ເ'] = 'pref_vowel', ['ແ'] = 'pref_vowel',
	['ໂ'] = 'pref_vowel', ['ໃ'] = 'pref_vowel', ['ໄ'] = 'pref_vowel',
	['ໆ'] = 'iter_symbol',
	['່'] = 'tone', ['້'] = 'tone', ['໊'] = 'tone', ['໋'] = 'tone',
	['໌'] = 'canc_symbol', ['ໍ'] = 'suf_vowel',
	['໐'] = 'number', ['໑'] = 'number', ['໒'] = 'number', ['໓'] = 'number', ['໔'] = 'number',
	['໕'] = 'number', ['໖'] = 'number', ['໗'] = 'number', ['໘'] = 'number', ['໙'] = 'number',
	['ໜ'] = 'cons', ['ໝ'] = 'cons'
}

function export.tr(text, lang, sc, debug_mode)
	text = gsub(text, '[່້໊໋​]', '')

	for lao_text in mw.ustring.gmatch(text, '[ກ-ໝ]+') do
		local word, c, chartype, output = {}, {}, {}, {}
		local curr_word, curr_initial, curr_vowel, curr_coda = {}, {}, {}, {}
		local i = 1
		local original_text = lao_text
		
		for i = 1, len(lao_text) do
			c[i] = sub(lao_text, i, i)
			chartype[i] = char_type[c[i]] or table.insert(word, c[i])
		end
	
		for i = 1, #c + 1 do
			if chartype[i] == 'pref_vowel' or i == #c + 1 then
				if #curr_word ~= 0 then
					table.insert(word, table.concat(curr_word))
					curr_word, curr_initial, curr_vowel, curr_coda = {c[i]}, {}, {c[i]}, {}
				else
					table.insert(curr_vowel, c[i])
					table.insert(curr_word, c[i])
				end
				
			elseif chartype[i] == 'suf_vowel' then
				table.insert(curr_vowel, c[i])
				table.insert(curr_word, c[i])
				
			elseif chartype[i] == 'ambig' then
				if #curr_initial ~= 0 and vowel_conv[table.concat(curr_vowel)..c[i]] and (chartype[i+1] ~= 'suf_vowel' or match(c[i+1], '[ໍຳີັ]')) and #curr_coda == 0 then
					table.insert(curr_vowel, c[i])
					table.insert(curr_word, c[i])
				elseif (#curr_initial == 0 and char_type[table.concat(curr_vowel)] == 'pref_vowel') or (#curr_initial ~= 0 and initial_conv[table.concat(curr_initial)..c[i]]) then
					table.insert(curr_initial, c[i])
					table.insert(curr_word, c[i])
				else
					if #curr_word ~= 0 then
						table.insert(word, table.concat(curr_word))
					end
					curr_word, curr_initial, curr_vowel, curr_coda = {c[i]}, {c[i]}, {}, {}
				end
			
			elseif chartype[i] == 'vowel_let' then
				table.insert(curr_vowel, c[i])
				table.insert(curr_word, c[i])
		
			elseif chartype[i] == 'coda' and #curr_coda == 0 and #curr_initial ~= 0 and chartype[i+1] ~= 'suf_vowel' and chartype[i+1] ~= 'vowel_let' and not (chartype[i+1] == 'ambig' and match(chartype[i+2] or '', 'co')) and table.concat(curr_vowel) ~= "ວີວ" then
				table.insert(curr_coda, c[i])
				table.insert(curr_word, c[i])

			elseif chartype[i] == 'cons' or chartype[i] == 'coda' then
				if #curr_coda == 0 and initial_conv[table.concat(curr_initial)..c[i]] and (#curr_vowel == 0 or char_type[table.concat(curr_vowel)] == 'pref_vowel') then
					table.insert(curr_initial, c[i])
					table.insert(curr_word, c[i])
				else
					table.insert(word, table.concat(curr_word))
					curr_word, curr_initial, curr_vowel, curr_coda = {c[i]}, {c[i]}, {}, {}
				end
			
			elseif chartype[i] == 'iter_symbol' then
				if #curr_word ~= 0 then
					table.insert(word, table.concat(curr_word))
				end
				curr_word, curr_initial, curr_vowel, curr_coda = {c[i]}, {}, {}, {}
		
			elseif chartype[i] == 'canc_symbol' then
				table.insert(curr_word, c[i])
		
			elseif chartype[i] == 'number' then
				table.insert(curr_word, sp_symbols[c[i]])
			end
		end
		for i = 1, #word do
			word[i] = gsub(word[i], '^([ເແໂໄໃຽ]?)(ຫ?[ກຂຄງຈສຊຍດຕຖທນບປຜຝພຟມຢຣລວຫອຮໜໝ]ຼ?)([^໌]*)(໌?)$', function(a, b, c, e)
				if match(sub(c, -1, -1), '[ກຂຄງຈສຊຍດຕຖທນບປຜຝພຟມຢຣລວ]') then
					d = sub(c, -1, -1)
					c = sub(c, 1, -2)
				else
					d = ''
				end
				if a..c == '' then
					c = 'ະ'
				end
				vowel = vowel_conv[a..c..d] or (vowel_conv[a..c] or a .. c) .. (coda_conv[d] or d)
				if match(vowel, '[ກ-ໝ]') then
					vowel = gsub(vowel, '^(.*)([ຍອວ])(.*)$', function(x, y, z)
						return (vowel_conv[x] or x) .. ' ' .. (initial_conv[y] or y) .. (vowel_conv[z] or z) end)
				end
				return (initial_conv[b] or b) .. vowel .. e end)
			
			if char_type[word[i]] == 'iter_symbol' and i >= 2 then
				word[i] = '<small><u>' .. word[i-1] .. '</u></small>'
			end
		
			if match(word[i], '໌') and len(word[i]) > 1 then
				word[i] = gsub(word[i], '(.)໌', '<small><del>%1</del></small>')
			end
			
			table.insert(output, word[i])
		end
		lao_text = table.concat(output, " ")
		lao_text = gsub(lao_text, '.', sp_symbols)
	
		text = gsub(text, original_text, lao_text)
	end

	if match(text, '[ກ-ໝ]') and not debug_mode then
		return nil
	else
		return text
	end
end

return export