Module:Category handler

    From Nonbinary Wiki

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

    --------------------------------------------------------------------------------
    --                                                                            --
    --                              CATEGORY HANDLER                              --
    --                                                                            --
    --      This module implements the {{category handler}} template in Lua,      --
    --      with a few improvements: all namespaces and all namespace aliases     --
    --      are supported, and namespace names are detected automatically for     --
    --      the local wiki. This module requires [[Module:Namespace detect]]      --
    --      and [[Module:Yesno]] to be available on the local wiki. It can be     --
    --      configured for different wikis by altering the values in              --
    --      [[Module:Category handler/config]], and pages can be blacklisted      --
    --      from categorisation by using [[Module:Category handler/blacklist]].   --
    --                                                                            --
    --------------------------------------------------------------------------------
    
    -- Load required modules
    local yesno = require('Module:Yesno')
    
    -- Lazily load things we don't always need
    local mShared, mappings
    
    local p = {}
    
    --------------------------------------------------------------------------------
    -- Helper functions
    --------------------------------------------------------------------------------
    
    local function trimWhitespace(s, removeBlanks)
    	if type(s) ~= 'string' then
    		return s
    	end
    	s = s:match('^%s*(.-)%s*$')
    	if removeBlanks then
    		if s ~= '' then
    			return s
    		else
    			return nil
    		end
    	else
    		return s
    	end
    end
    
    --------------------------------------------------------------------------------
    -- CategoryHandler class
    --------------------------------------------------------------------------------
    
    local CategoryHandler = {}
    CategoryHandler.__index = CategoryHandler
    
    function CategoryHandler.new(data, args)
    	local obj = setmetatable({ _data = data, _args = args }, CategoryHandler)
    
    	-- Set the title object
    	do
    		local pagename = obj:parameter('demopage')
    		local success, titleObj
    		if pagename then
    			success, titleObj = pcall(mw.title.new, pagename)
    		end
    		if success and titleObj then
    			obj.title = titleObj
    			if titleObj == mw.title.getCurrentTitle() then
    				obj._usesCurrentTitle = true
    			end
    		else
    			obj.title = mw.title.getCurrentTitle()
    			obj._usesCurrentTitle = true
    		end
    	end
    
    	-- Set suppression parameter values
    	for _, key in ipairs{'nocat', 'categories'} do
    		local value = obj:parameter(key)
    		value = trimWhitespace(value, true)
    		obj['_' .. key] = yesno(value)
    	end
    	do
    		local subpage = obj:parameter('subpage')
    		local category2 = obj:parameter('category2')
    		if type(subpage) == 'string' then
    			subpage = mw.ustring.lower(subpage)
    		end
    		if type(category2) == 'string' then
    			subpage = mw.ustring.lower(category2)
    		end
    		obj._subpage = trimWhitespace(subpage, true)
    		obj._category2 = trimWhitespace(category2) -- don't remove blank values
    	end
    	return obj
    end
    
    function CategoryHandler:parameter(key)
    	local parameterNames = self._data.parameters[key]
    	local pntype = type(parameterNames)
    	if pntype == 'string' or pntype == 'number' then
    		return self._args[parameterNames]
    	elseif pntype == 'table' then
    		for _, name in ipairs(parameterNames) do
    			local value = self._args[name]
    			if value ~= nil then
    				return value
    			end
    		end
    		return nil
    	else
    		error(string.format(
    			'invalid config key "%s"',
    			tostring(key)
    		), 2)
    	end
    end
    
    function CategoryHandler:isSuppressedByArguments()
    	return
    		-- See if a category suppression argument has been set.
    		self._nocat == true
    		or self._categories == false
    		or (
    			self._category2
    			and self._category2 ~= self._data.category2Yes
    			and self._category2 ~= self._data.category2Negative
    		)
    
    		-- Check whether we are on a subpage, and see if categories are
    		-- suppressed based on our subpage status.
    		or self._subpage == self._data.subpageNo and self.title.isSubpage
    		or self._subpage == self._data.subpageOnly and not self.title.isSubpage
    end
    
    function CategoryHandler:shouldSkipBlacklistCheck()
    	-- Check whether the category suppression arguments indicate we
    	-- should skip the blacklist check.
    	return self._nocat == false
    		or self._categories == true
    		or self._category2 == self._data.category2Yes
    end
    
    function CategoryHandler:matchesBlacklist()
    	if self._usesCurrentTitle then
    		return self._data.currentTitleMatchesBlacklist
    	else
    		mShared = mShared or require('Module:Category handler/shared')
    		return mShared.matchesBlacklist(
    			self.title.prefixedText,
    			mw.loadData('Module:Category handler/blacklist')
    		)
    	end
    end
    
    function CategoryHandler:isSuppressed()
    	-- Find if categories are suppressed by either the arguments or by
    	-- matching the blacklist.
    	return self:isSuppressedByArguments()
    		or not self:shouldSkipBlacklistCheck() and self:matchesBlacklist()
    end
    
    function CategoryHandler:getNamespaceParameters()
    	if self._usesCurrentTitle then
    		return self._data.currentTitleNamespaceParameters
    	else
    		if not mappings then
    			mShared = mShared or require('Module:Category handler/shared')
    			mappings = mShared.getParamMappings(true) -- gets mappings with mw.loadData
    		end
    		return mShared.getNamespaceParameters(
    			self.title,
    			mappings
    		)
    	end
    end
    
    function CategoryHandler:namespaceParametersExist()
    	-- Find whether any namespace parameters have been specified.
    	-- We use the order "all" --> namespace params --> "other" as this is what
    	-- the old template did.
    	if self:parameter('all') then
    		return true
    	end
    	if not mappings then
    		mShared = mShared or require('Module:Category handler/shared')
    		mappings = mShared.getParamMappings(true) -- gets mappings with mw.loadData
    	end
    	for ns, params in pairs(mappings) do
    		for i, param in ipairs(params) do
    			if self._args[param] then
    				return true
    			end
    		end
    	end
    	if self:parameter('other') then
    		return true
    	end
    	return false
    end
    
    function CategoryHandler:getCategories()
    	local params = self:getNamespaceParameters()
    	local nsCategory
    	for i, param in ipairs(params) do
    		local value = self._args[param]
    		if value ~= nil then
    			nsCategory = value
    			break
    		end
    	end
    	if nsCategory ~= nil or self:namespaceParametersExist() then
    		-- Namespace parameters exist - advanced usage.
    		if nsCategory == nil then
    			nsCategory = self:parameter('other')
    		end
    		local ret = {self:parameter('all')}
    		local numParam = tonumber(nsCategory)
    		if numParam and numParam >= 1 and math.floor(numParam) == numParam then
    			-- nsCategory is an integer
    			ret[#ret + 1] = self._args[numParam]
    		else
    			ret[#ret + 1] = nsCategory
    		end
    		if #ret < 1 then
    			return nil
    		else
    			return table.concat(ret)
    		end
    	elseif self._data.defaultNamespaces[self.title.namespace] then
    		-- Namespace parameters don't exist, simple usage.
    		return self._args[1]
    	end
    	return nil
    end
    
    --------------------------------------------------------------------------------
    -- Exports
    --------------------------------------------------------------------------------
    
    local p = {}
    
    function p._exportClasses()
    	-- Used for testing purposes.
    	return {
    		CategoryHandler = CategoryHandler
    	}
    end
    
    function p._main(args, data)
    	data = data or mw.loadData('Module:Category handler/data')
    	local handler = CategoryHandler.new(data, args)
    	if handler:isSuppressed() then
    		return nil
    	end
    	return handler:getCategories()
    end
    
    function p.main(frame, data)
    	data = data or mw.loadData('Module:Category handler/data')
    	local args = require('Module:Arguments').getArgs(frame, {
    		wrappers = data.wrappers,
    		valueFunc = function (k, v)
    			v = trimWhitespace(v)
    			if type(k) == 'number' then
    				if v ~= '' then
    					return v
    				else
    					return nil
    				end
    			else
    				return v
    			end
    		end
    	})
    	return p._main(args, data)
    end
    
    return p