namespace Detect

--[[ -------------------------------------------------------------------------------- --                                                                            -- --                            NAMESPACE DETECT                                -- --                                                                            -- -- This module implements the {{namespace detect}} 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. The     -- -- module can also use the corresponding subject namespace value if it is     -- -- used on a talk page. Parameter names can be configured for different wikis -- -- by altering the values in the "cfg" table in                               -- -- Module:Namespace detect/config.                                            -- --                                                                            -- -------------------------------------------------------------------------------- --]]  local data = mw.loadData('Module:Namespace detect/data') local argKeys = data.argKeys local cfg = data.cfg local mappings = data.mappings  local yesno = require('Module:Yesno') local mArguments -- Lazily initialise Module:Arguments local mTableTools -- Lazily initilalise Module:TableTools local ustringLower = mw.ustring.lower  local p = {}  local function fetchValue(t1, t2) -- Fetches a value from the table t1 for the first key in array t2 where -- a non-nil value of t1 exists. for i, key in ipairs(t2) do local value = t1[key] if value ~= nil then return value end end return nil end  local function equalsArrayValue(t, value) -- Returns true if value equals a value in the array t. Otherwise -- returns false. for i, arrayValue in ipairs(t) do if value == arrayValue then return true end end return false end  function p.getPageObject(page) -- Get the page object, passing the function through pcall in case of -- errors, e.g. being over the expensive function count limit. if page then local success, pageObject = pcall(mw.title.new, page) if success then return pageObject else return nil end else return mw.title.getCurrentTitle() end end  -- Provided for backward compatibility with other modules function p.getParamMappings() return mappings end  local function getNamespace(args) -- This function gets the namespace name from the page object. local page = fetchValue(args, argKeys.demopage) if page == '' then page = nil end local demospace = fetchValue(args, argKeys.demospace) if demospace == '' then demospace = nil end local subjectns = fetchValue(args, argKeys.subjectns) local ret if demospace then -- Handle "demospace = main" properly. if equalsArrayValue(argKeys.main, ustringLower(demospace)) then ret = mw.site.namespaces[0].name else ret = demospace end else local pageObject = p.getPageObject(page) if pageObject then if pageObject.isTalkPage then -- Get the subject namespace if the option is set, -- otherwise use "talk". if yesno(subjectns) then ret = mw.site.namespaces[pageObject.namespace].subject.name else ret = 'talk' end else ret = pageObject.nsText end else return nil -- return nil if the page object doesn't exist. end end ret = ret:gsub('_', ' ') return ustringLower(ret) end  function p._main(args) -- Check the parameters stored in the mappings table for any matches. local namespace = getNamespace(args) or 'other' -- "other" avoids nil table keys local params = mappings[namespace] or {} local ret = fetchValue(args, params) --[[ -- If there were no matches, return parameters for other namespaces. -- This happens if there was no text specified for the namespace that -- was detected or if the demospace parameter is not a valid -- namespace. Note that the parameter for the detected namespace must be -- completely absent for this to happen, not merely blank. --]] if ret == nil then ret = fetchValue(args, argKeys.other) end return ret end  function p.main(frame) mArguments = require('Module:Arguments') local args = mArguments.getArgs(frame, {removeBlanks = false}) local ret = p._main(args) return ret or '' end  function p.table(frame) --[[ -- Create a wikitable table-responsive  of all subject namespace parameters, for -- documentation purposes. The talk parameter is optional, in case it -- needs to be excluded in the documentation. --]]  -- Load modules and initialise variables. mTableTools = require('Module:TableTools') local namespaces = mw.site.namespaces local cfg = data.cfg local useTalk = type(frame) == 'table'  and type(frame.args) == 'table'  and yesno(frame.args.talk) -- Whether to use the talk parameter.  -- Get the header names. local function checkValue(value, default) if type(value) == 'string' then return value else return default end end local nsHeader = checkValue(cfg.wikitable table-responsive NamespaceHeader, 'Namespace') local aliasesHeader = checkValue(cfg.wikitable table-responsive AliasesHeader, 'Aliases')  -- Put the namespaces in order. local mappingsOrdered = {} for nsname, params in pairs(mappings) do if useTalk or nsname ~= 'talk' then local nsid = namespaces[nsname].id -- Add 1, as the array must start with 1; nsid 0 would be lost otherwise. nsid = nsid + 1  mappingsOrdered[nsid] = params end end mappingsOrdered = mTableTools.compressSparseArray(mappingsOrdered)  -- Build the table. local ret = '{| class="duhoc-fo wikitable table-responsive "' .. '\n|-' .. '\n! ' .. nsHeader .. '\n! ' .. aliasesHeader for i, params in ipairs(mappingsOrdered) do for j, param in ipairs(params) do if j == 1 then ret = ret .. '\n|-' .. '\n| ' .. param .. '' .. '\n| ' elseif j == 2 then ret = ret .. '' .. param .. '' else ret = ret .. ', ' .. param .. '' end end end ret = ret .. '\n|-' .. '\n|}' return ret end  return p