Module:User:Erutuon/Unicode data/sandbox

local export = {}

local floor = math.floor

local function errorf(...)
	local first_arg = ...
	if type(first_arg) == "number" then
		return error(string.format(select(2, ...)), first_arg + 1)
	else
		return error(string.format(...), 2)
	end
end

local function binary_range_search(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
		if codepoint < range then
			high = mid - 1
		elseif codepoint <= range then
			return range, mid
		else
			low = mid + 1
		end
	end
	return nil, mid
end
export.binary_range_search = binary_range_search

local function linear_range_search(codepoint, ranges)
	for i, range in ipairs(ranges) do
		if codepoint < range then
			break
		elseif codepoint <= range then
			return range
		end
	end
end

-- Load a module by indexing "loader" with the name of the module minus the
-- "Module:Unicode data/" part. For instance, loader.blocks returns
-- ]. If a module cannot be loaded, false will be
-- returned.
local loader = setmetatable({}, {
	__index = function (self, key)
		local success, data = pcall(mw.loadData, "Module:Unicode data/" .. key)
		if not success then
			data = false
		end
		self = data
		return data
	end
})

-- For the algorithm used to generate Hangul Syllable names,
-- see "Hangul Syllable Name Generation" in section 3.12 of the
-- Unicode Specification:
-- https://www.unicode.org/versions/Unicode11.0.0/ch03.pdf
local name_hooks = {
	{     0x00,     0x1F, "<control-%04X>" }, -- C0 control characters
	{     0x7F,     0x9F, "<control-%04X>" }, -- DEL and C1 control characters
	{   0x2800,   0x28FF, function (codepoint)
		-- assert(0x2801 <= codepoint and codepoint <= 0x28FF)
		local pattern_num = codepoint - 0x2800
		if pattern_num == 0 then return "BRAILLE PATTERN BLANK" end
		local name = {}
		local i = 0
		repeat
			i = i + 1
			if pattern_num % 2 == 0 then
				pattern_num = pattern_num / 2
			else
				table.insert(name, i)
				pattern_num = floor(pattern_num / 2)
			end
		until pattern_num == 0
		table.insert(name, 1, "BRAILLE PATTERN DOTS-")
		return table.concat(name)
	end },
	{   0x3400,   0x4DB5, "CJK UNIFIED IDEOGRAPH-%04X" }, -- CJK Ideograph Extension A
	{   0x4E00,   0x9FEF, "CJK UNIFIED IDEOGRAPH-%04X" }, -- CJK Ideograph
	{   0xAC00,   0xD7A3, function (codepoint) -- Hangul Syllables
		local Hangul_data = loader.Hangul
		local syllable_index = codepoint - 0xAC00

		return ("HANGUL SYLLABLE %s%s%s"):format(
			Hangul_data.leads,
			Hangul_data.vowels[floor((syllable_index % Hangul_data.final_count)
				/ Hangul_data.trail_count)],
			Hangul_data.trails
		)
	end },
	-- High Surrogates, High Private Use Surrogates, Low Surrogates
	{   0xD800,   0xDFFF, "<surrogate-%04X>" },
	{   0xE000,   0xF8FF, "<private-use-%04X>" }, -- Private Use
	-- CJK Compatibility Ideographs
	{   0xF900,   0xFA6D, "CJK COMPATIBILITY IDEOGRAPH-%04X" },
	{   0xFA70,   0xFAD9, "CJK COMPATIBILITY IDEOGRAPH-%04X" },
	{  0x17000,  0x187F1, "TANGUT IDEOGRAPH-%04X" }, -- Tangut
	{  0x18800,  0x18AF2, function (codepoint)
		return ("TANGUT COMPONENT-%03d"):format(codepoint - 0x18800 + 1)
	end },
	{  0x1B170,  0x1B2FB, "NUSHU CHARACTER-%04X" }, -- Nushu
	{  0x1D200,  0x1D21C, function (codepoint)
		return ("GREEK VOCAL NOTATION SYMBOL-%d"):format(codepoint - 0x1D200 + 1)
	end },
	{  0x1D21D,  0x1D241, function (codepoint)
		return ("GREEK INSTRUMENTAL NOTATION SYMBOL-%d"):format(codepoint - 0x1D21D + 1)
	end },
	{  0x1F031,  0x1F061, function (codepoint)
		local num = codepoint - 0x1F031
		return ("DOMINO TILE HORIZONTAL-%02d-%02d"):format(num % 7, floor(num / 7))
	end },
	{  0x1F063,  0x1F093, function (codepoint)
		local num = codepoint - 0x1F063
		return ("DOMINO TILE VERTICAL-%02d-%02d"):format(num % 7, floor(num / 7))
	end },
	{  0x1F0E1,  0x1F0F5, function (codepoint)
		return ("PLAYING CARD TRUMP-%d"):format(codepoint - 0x1F0E1 + 1)
	end },
	{  0x1F1E6,  0x1F1FF, function (codepoint)
		return ("REGIONAL INDICATOR SYMBOL LETTER %c"):format(codepoint - 0x1F1E6 + ("A"):byte())
	end },
	{  0x20000,  0x2A6D6, "CJK UNIFIED IDEOGRAPH-%04X" }, -- CJK Ideograph Extension B
	{  0x2A700,  0x2B734, "CJK UNIFIED IDEOGRAPH-%04X" }, -- CJK Ideograph Extension C
	{  0x2A740,  0x2B81D, "CJK UNIFIED IDEOGRAPH-%04X" }, -- CJK Ideograph Extension D
	{  0x2B820,  0x2CEA1, "CJK UNIFIED IDEOGRAPH-%04X" }, -- CJK Ideograph Extension E
	{  0x2CEB0,  0x2EBE0, "CJK UNIFIED IDEOGRAPH-%04X" }, -- CJK Ideograph Extension F
	-- CJK Compatibility Ideographs Supplement (Supplementary Ideographic Plane)
	{  0x2F800,  0x2FA1D, "CJK COMPATIBILITY IDEOGRAPH-%04X" },
	{  0xE0100,  0xE01EF, function (codepoint) -- Variation Selectors Supplement
		return ("VARIATION SELECTOR-%d"):format(codepoint - 0xE0100 + 17)
	end},
	{  0xF0000,  0xFFFFD, "<private-use-%04X>" }, -- Plane 15 Private Use
	{ 0x100000, 0x10FFFD, "<private-use-%04X>" }  -- Plane 16 Private Use
}
name_hooks.length = #name_hooks

local name_range_cache

local function generate_name(data, codepoint)
	if type(data) == "string" then
		return data:format(codepoint)
	else
		return data(codepoint)
	end
end

--[[
-- Checks that the code point is a number and in range.
-- Does not check whether code point is an integer.
-- Not used
local function check_codepoint(funcName, argIdx, val)
	require 'libraryUtil'.checkType(funcName, argIdx, val, 'number')
	if codepoint < 0 or 0x10FFFF < codepoint then
		errorf("Codepoint %04X out of range", codepoint)
	end
end
--]]

-- https://www.unicode.org/versions/Unicode11.0.0/ch04.pdf, section 4.8
function export.get_name(codepoint)
	-- U+FDD0-U+FDEF and all code points ending in FFFE or FFFF are Unassigned
	-- (Cn) and specifically noncharacters:
	-- https://www.unicode.org/faq/private_use.html#nonchar4
	if 0xFDD0 <= codepoint and (codepoint <= 0xFDEF
			or floor(codepoint % 0x10000) >= 0xFFFE) then
		return ("<noncharacter-%04X>"):format(codepoint)
	end

	if name_range_cache -- Check if previously used "name hook" applies to this code point.
			and codepoint >= name_range_cache
			and codepoint <= name_range_cache then
		return generate_name(name_range_cache, codepoint)
	end
	
	local range = binary_range_search(codepoint, name_hooks)
	if range then
		name_range_cache = range
		return generate_name(range, codepoint)
	end

	local data = loader
	
	if data and data then
		return data
	
	-- Unassigned (Cn) consists of noncharacters and reserved characters.
	-- The character has been established not to be a noncharacter,
	-- and if it were assigned, its name would already been retrieved,
	-- so it must be reserved.
	else
		return ("<reserved-%04X>"):format(codepoint)
	end
end

function export.get_image(codepoint)
	local data = loader
	
	if data then
		return data
	end
end

local planes = {
	 = "Basic Multilingual Plane";
	 = "Supplementary Multilingual Plane";
	 = "Supplementary Ideographic Plane";
	 = "Supplementary Special-purpose Plane";
	 = "Supplementary Private Use Area-A";
	 = "Supplementary Private Use Area-B";
}

-- Load ] if needed and assign it to this variable.
local blocks

local function block_iter(blocks, i)
	i = i + 1
	local data = blocks
	if data then
		 -- Unpack doesn't work on tables loaded with mw.loadData.
		return i, data, data, data
	end
end

-- An ipairs-type iterator generator for the list of blocks.
function export.enum_blocks()
	local blocks = loader.blocks
	return block_iter, blocks, 0
end

function export.get_block_range(name)
	local range
	
	for i, block in ipairs(loader.blocks) do
		if block == name then
			range = block
		end
	end
	
	if range then
		return range, range
	end
end

function export.get_plane(codepoint)
	local i = floor(codepoint / 0x10000)
	return planes or ("Plane %u"):format(i)
end

function export.get_block(codepoint)
	local blocks = loader.blocks
	local range = binary_range_search(codepoint, blocks)
	if range then
		return range
	else
		return "No Block"
	end
end

function export.get_block_info(name)
	for i, block in ipairs(loader.blocks) do
		if block == name then
			return block
		end
	end
end

function export.is_valid_pagename(pagename)
	local has_nonws = false

	for cp in mw.ustring.gcodepoint(pagename) do
		if (cp == 0x0023) -- #
		or (cp == 0x005B) -- [
		or (cp == 0x005D) -- ]
		or (cp == 0x007B) -- {
		or (cp == 0x007C) -- |
		or (cp == 0x007D) -- }
		or (cp == 0x180E) -- MONGOLIAN VOWEL SEPARATOR
		or ((cp >= 0x2000) and (cp <= 0x200A)) -- spaces in General Punctuation block
		or (cp == 0xFFFD) -- REPLACEMENT CHARACTER
		then
			return false
		end

		local printable, result = export.is_printable(cp)
		if not printable then
			return false
		end

		if result ~= "space-separator" then
			has_nonws = true
		end
	end

	return has_nonws
end

local function manual_unpack(what, from)
	if what == nil then
		return what
	end
	
	local result = {}
	from = from or 1
	for i, item in ipairs(what) do
		if i >= from then
			table.insert(result, item)
		end
	end
	return unpack(result)
end

local function compare_ranges(range1, range2)
	return range1 < range2
end

-- Creates a function to look up data in a module that contains "singles" (a
-- code point-to-data map) and "ranges" (an array containing arrays that contain
-- the low and high code points of a range and the data associated with that
-- range).
-- "loader" loads and returns the "singles" and "ranges" tables.
-- "match_func" is passed the code point and either the data or the "dots", and
-- generates the final result of the function.
-- The varargs ("dots") describes the default data to be returned if there wasn't
-- a match.
-- In case the function is used more than once, "cache" saves ranges that have
-- already been found to match, or a range whose data is the default if there
-- was no match.
local function memo_lookup(data_module_subpage, match_func, ...)
	local dots = { ... }
	local cache = {}
	local singles, ranges

	return function (codepoint)
		if not singles then
			local data_module = loader
			singles, ranges = data_module.singles, data_module.ranges
		end

		if singles then
			return match_func(codepoint, singles)
		end

		local range = binary_range_search(codepoint, cache)
		if range then
			return match_func(codepoint, manual_unpack(range, 3))
		end
		
		local range, index = binary_range_search(codepoint, ranges)
		if range then
			table.insert(cache, range)
			table.sort(cache, compare_ranges)
			return match_func(codepoint, manual_unpack(range, 3))
		end
		
		if ranges then
			local dots_range
			if codepoint > ranges then
				dots_range = {
					ranges + 1,
					ranges and ranges - 1 or 0x10FFFF,
					unpack(dots)
				}
			else -- codepoint < range
				dots_range = {
					ranges and ranges + 1 or 0,
					ranges - 1,
					unpack(dots)
				}
			end
			table.sort(cache, compare_ranges)
		end
		
		return match_func(codepoint)
	end
end

-- Get a code point's combining class value in ],
-- and return whether this value is not zero. Zero is assigned as the default
-- if the combining class value is not found in this data module.
-- That is, return true if character is combining, or false if it is not.
-- See https://www.unicode.org/reports/tr44/#Canonical_Combining_Class_Values for
-- more information.
export.is_combining = memo_lookup(
	"combining",
	function (codepoint, combining_class)
		return combining_class and combining_class ~= 0 or false
	end,
	0)

function export.add_dotted_circle(str)
	return (mw.ustring.gsub(str, ".",
		function(char)
			if export.is_combining(mw.ustring.codepoint(char)) then
				return '◌' .. char
			end
		end))
end

local get_control = memo_lookup(
	"control",
	function (codepoint, ccc)
		return ccc or "assigned"
	end,
	"assigned")
export.get_control = get_control

function export.is_assigned(codepoint)
	return get_control(codepoint) ~= "unassigned"
end

function export.is_printable(codepoint)
	local result = get_control(codepoint)
	return (result == "assigned") or (result == "space-separator"), result
end

function export.is_whitespace(codepoint)
	local result = get_control(codepoint)
	return (result == "space-separator"), result
end

export.get_category = memo_lookup(
	"category",
	function (codepoint, category)
		return category
	end,
	"Cn")

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

--[=[
	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
	]. The data module was generated from the
	patterns in ] using ].

	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".
]=]
function export.char_to_script(char)
	local lookup = loader.scripts
	local t = type(char)
	local codepoint
	if t == "string" then
		local etc
		codepoint, etc = mw.ustring.codepoint(char)
		if etc then
			error("Argument to char_to_script should be a single character.")
		end
	elseif t == "number" then
		codepoint = char
	else
		error(("bad argument #1 to 'char_to_script' (expected string or a number, got %s)")
			:format(t))
	end

	local individual_match = lookup.individual
	if individual_match then
		return individual_match
	else
		local range
		if ranges_cache then
			range = linear_range_search(codepoint, ranges_cache)
			if range then
				return range
			end
		end

		local index = floor(codepoint / 0x1000)

		range = linear_range_search(index, lookup.blocks)
		if not range and lookup then
			range = binary_range_search(codepoint, lookup)
			if range then
				table.insert(ranges_cache, range)
				table.sort(ranges_cache, compare_ranges)
			end
		end
		
		return range and range or "None"
	end
end

function export.find_best_script(text)
	local scripts = {}
	for character in text:gmatch("*") do
		local script = export.char_to_script(character)
		scripts = (scripts or 0) + 1
	end
	
	local best_script
	local greatest_count = 0
	for script, count in pairs(scripts) do
		if count > greatest_count then
			best_script = script
			greatest_count = count
		end
	end
	
	return best_script
end

local unsupported_title = {
	 = "Unsupported titles/Space";
	 = "Unsupported titles/Number sign";
	 = "Unsupported titles/Full stop";
	 = "Unsupported titles/Colon";
	 = "Unsupported titles/Less than";
	 = "Unsupported titles/Greater than";
	 = "Unsupported titles/Left square bracket";
	 = "Unsupported titles/Right square bracket";
	 = "Unsupported titles/Low line";
	 = "Unsupported titles/Left curly bracket";
	 = "Unsupported titles/Vertical line";
	 = "Unsupported titles/Right curly bracket";
	 = "Unsupported titles/Ogham space";
	 = "Unsupported titles/Replacement character";
}

function export.get_entry_title(codepoint)
	if unsupported_title then
		return unsupported_title
	end
	if get_control(codepoint) ~= "assigned" then
		return nil
	end
	return mw.ustring.char(codepoint)
end

setmetatable(export, {
	__index = function(self, key)
		if type(key) == "string" then
			local count
			key, count = key:gsub("^lookup_", "get_")
			if count == 1 then
				return rawget(self, key)
			end
		end
	end,
})

return export