Module:scripts

Documentation for this module may be created at Module:scripts/doc

local export = {}
local Script = {}

function Script:getCode()
	return self._code
end

function Script:getCanonicalName()
	return self._rawData.canonicalName
end

function Script:getDisplayForm()
	return self:getCategoryName()
end

function Script:getOtherNames(onlyOtherNames)
	return require("Module:language-like").getOtherNames(self, onlyOtherNames)
end

function Script:getAliases()
	return self._rawData.aliases or {}
end

function Script:getVarieties(flatten)
	return require("Module:language-like").getVarieties(self, flatten)
end

function Script:getParent()
	return self._rawData.parent
end

function Script:getSystems()
	if not self._systemObjects then
		local m_systems = require("Module:writing systems")
		self._systemObjects = {}
		
		for _, sys in ipairs(self._rawData.systems or {}) do
			table.insert(self._systemObjects, m_systems.getByCode(sys))
		end
	end
	
	return self._systemObjects
end

--function Script:getAllNames()
--	return self._rawData.names
--end


function Script:getType()
	return "script"
end


function Script:getCategoryName()
	local name = self._rawData.canonicalName
	
	-- If the name already has "code" or "semaphore" in it, don't add it.
	-- No names contain "script".
	if name:find("[Cc]ode$") or name:find("[Ss]emaphore$") then
		return name
	else
		return name .. " script"
	end
end


function Script:makeCategoryLink()
	return "[[:Category:" .. self:getCategoryName() .. "|" .. self:getDisplayForm() .. "]]"
end


function Script:getWikipediaArticle()
	return self._rawData.wikipedia_article or self:getCategoryName()
end


function Script:getCharacters()
	if self._rawData.characters then
		return self._rawData.characters
	else
		return nil
	end
end


function Script:countCharacters(text)
	if not self._rawData.characters then
		return 0
	else
		local _, num = mw.ustring.gsub(text, "[" .. self._rawData.characters .. "]", "")
		return num
	end
end

function Script:getDirection()
	local direction = self._rawData.direction
	if not direction then
		return nil
	else
		return direction
	end
end


function Script:getRawData()
	return self._rawData
end


function Script:toJSON()
	local ret = {
		canonicalName = self:getCanonicalName(),
		categoryName = self:getCategoryName(),
		code = self._code,
		otherNames = self:getOtherNames(true),
		aliases = self:getAliases(),
		varieties = self:getVarieties(),
		type = self:getType(),
		direction = self:getDirection(),
		characters = self:getCharacters(),
		parent = self:getParent(),
		systems = self._rawData.systems or {},
		wikipediaArticle = self._rawData.wikipedia_article,
	}
	
	return require("Module:JSON").toJSON(ret)
end


Script.__index = Script


function export.makeObject(code, data)
	return data and setmetatable({ _rawData = data, _code = code }, Script) or nil
end


function export.getByCode(code, paramForError, disallowNil)
	if code == nil and not disallowNil then
		return nil
	end
	if code == "IPAchar" then
		require("Module:debug").track("IPAchar")
	end
	local retval = export.makeObject(code, mw.loadData("Module:scripts/data")[code])
	if not retval and paramForError then
		require("Module:languages").err(code, paramForError, "script code", nil, "not real lang")
	end
	return retval
end

function export.getByCanonicalName(name)
	local code = mw.loadData("Module:scripts/by name")[name]
	
	if not code then
		return nil
	end
	
	return export.makeObject(code, mw.loadData("Module:scripts/data")[code])
end

-- Find the best script to use, based on the characters of a string.
-- If forceDetect is set, run the detection algorithm even if there's only one
-- possible script; in that case, if the text isn't in the script, the return
-- value will be None.
function export.findBestScript(text, lang, forceDetect)
	if not text or not lang or not lang.getScripts then
		return export.getByCode("None")
	end
	
	local scripts = lang:getScripts()
	
	if not scripts[2] and not forceDetect then
		return scripts[1]
	end
	
	--[=[
		Remove any HTML entities; catfix function in [[Module:utilities]]
		adds tagging to a no-break space ( ), which contains Latin characters;
		hence Latin was returned as the script if "Latn" is one of the language's scripts.
	]=]
	text = string.gsub(text, "&[a-zA-Z0-9]+;", "")
	
	-- Try to match every script against the text,
	-- and return the one with the most matching characters.
	local bestcount = 0
	local bestscript = nil
	
	-- Get length of text minus any spacing or punctuation characters.
	-- Counting instances of UTF-8 character pattern is faster than mw.ustring.len.
	local _, length = string.gsub(mw.ustring.gsub(text, "[%s%p]+", ""), "[\1-\127\194-\244][\128-\191]*", "")
	
	if length == 0 then
		return export.getByCode("None")
	end
	
	for i, script in ipairs(scripts) do
		local count = script:countCharacters(text)
		
		if count >= length then
			return script
		end
		
		if count > bestcount then
			bestcount = count
			bestscript = script
		end
	end
	
	if bestscript then
		return bestscript
	end
	
	-- No matching script was found. Return "None".
	return export.getByCode("None")
end

-- Copied from [[Module:Unicode data]].
local floor = math.floor
local function binaryRangeSearch(codepoint, ranges)
	local low, mid, high
	low, high = 1, ranges.length or require "Module:table".length(ranges)
	while low <= high do
		mid = floor((low + high) / 2)
		local range = ranges[mid]
		if codepoint < range[1] then
			high = mid - 1
		elseif codepoint <= range[2] then
			return range, mid
		else
			low = mid + 1
		end
	end
	return nil, mid
end

-- Copied from [[Module:Unicode data]].
local function linearRangeSearch(codepoint, ranges)
	for i, range in ipairs(ranges) do
		if codepoint < range[1] then
			break
		elseif codepoint <= range[2] then
			return range
		end
	end
end

local function compareRanges(range1, range2)
	return range1[1] < range2[1]
end

-- Save previously used codepoint ranges in case another character is in the
-- same range.
local rangesCache = {}

--[=[
	Takes a codepoint or a character and finds the script code (if any) that is
	appropriate for it based on the codepoint, using the data module
	[[Module:scripts/recognition data]]. The data module was generated from the
	patterns in [[Module:scripts/data]] using [[Module:User:Erutuon/script recognition]].

	Converts the character to a codepoint. Returns a script code if the codepoint
	is in the list of individual characters, or if it is in one of the defined
	ranges in the 4096-character block that it belongs to, else returns "None".
]=]
local charToScriptData
function export.charToScript(char)
	charToScriptData = charToScriptData or mw.loadData("Module:scripts/recognition data")
	local t = type(char)
	local codepoint
	if t == "string" then
		local etc
		codepoint, etc = mw.ustring.codepoint(char, 1, 2)
		if etc then
			error("bad argument #1 to 'charToScript' (expected a single character)")
		end
	elseif t == "number" then
		codepoint = char
	else
		error(("bad argument #1 to 'charToScript' (expected string or a number, got %s)")
			:format(t))
	end

	local individualMatch = charToScriptData.individual[codepoint]
	if individualMatch then
		return individualMatch
	else
		local range
		if rangesCache[1] then
			range = linearRangeSearch(codepoint, rangesCache)
			if range then
				return range[3]
			end
		end

		local index = floor(codepoint / 0x1000)

		range = linearRangeSearch(index, charToScriptData.blocks)
		if not range and charToScriptData[index] then
			range = binaryRangeSearch(codepoint, charToScriptData[index])
			if range then
				table.insert(rangesCache, range)
				table.sort(rangesCache, compareRanges)
			end
		end
		
		return range and range[3] or "None"
	end
end

function export.findBestScriptWithoutLang(text)
	local scripts = {}
	for character in text:gmatch("[%z\1-\127\194-\244][\128-\191]*") do
		local script = export.charToScript(character)
		scripts[script] = (scripts[script] or 0) + 1
	end
	
	local bestScript
	local greatestCount = 0
	for script, count in pairs(scripts) do
		if count > greatestCount then
			bestScript = script
			greatestCount = count
		end
	end
	
	return bestScript
end

return export