Module:Namespace detect

---

-- -- -- NAMESPACE DETECT -- -- -- -- This module implements the 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. Function names -- -- can be configured for different wikis by altering the -- -- values in the "cfg" table. -- -- --

---

---

-- Configuration data -- -- Language-specific parameter names can be set here. --

---

local cfg = {}

-- The name for the parameter to display content for the main namespace: cfg.main = 'main'

-- The name for the parameter to display content in talk namespaces: cfg.talk = 'talk'

-- The name for the parameter to display content for "other" namespaces -- (namespaces for which parameters have not been specified, or for when -- cfg.demospace is set to cfg.other): cfg.other = 'other'

-- The name for the parameter to set a demonstration namespace: cfg.demospace = 'demospace'

-- The name for the parameter to set a specific page to compare: cfg.page = 'page'

-- The header for the namespace column in the wikitable containing the -- list of possible subject-space parameters. cfg.wikitableNamespaceHeader = 'Namespace'

-- The header for the wikitable containing the list of possible -- subject-space parameters. cfg.wikitableAliasesHeader = 'Aliases'

---

-- End configuration data --

---

-- Specify variables available to the whole module local p = {} local args = {}

-- Get the page object. This will return the page object for the page -- specified, or nil if there are errors in the title or if the -- expensive function count has been exceeded. local function getPageObject()

   -- Get the title object for args.page if it is specified. Otherwise
   -- get the title object for the current page.
   if args[cfg.page] then
       -- Get the page object, passing the function through pcall 
       -- in case we are over the expensive function count limit.
       local noError, pageObject = pcall(mw.title.new, args[cfg.page])
       if not noError then
           return nil
       else
           return pageObject
       end
   else
       return mw.title.getCurrentTitle()
   end    

end

-- Detects the namespace for a page object. local function detectNamespace(pageObject)

   if pageObject.isTalkPage then
       -- Returns the value of cfg.talk or the local "Talk" namespace name. 
       return cfg.talk or mw.site.namespaces[1].name
   else
       return pageObject.nsText
   end

end

-- Gets the namespace name to compare to the arguments. The returned value -- is lower-case. local function getNamespace()

   local ret
   if args[cfg.demospace] then
       -- Handle "demospace = main" properly.
       if mw.ustring.lower( args[cfg.demospace] ) == cfg.main then
           ret = mw.site.namespaces[0].name
       else
           ret = args[cfg.demospace]
       end
   else
       local pageObject = getPageObject()
       if pageObject then
           ret = detectNamespace( getPageObject() )
       else
           return nil -- return nil if the page object doesn't exist.
       end
   end
   return mw.ustring.lower(ret)

end

-- Compare the namespace found with the parameters that have been -- specified, and return content of the appropriate parameter. local function compare()

   local namespace = getNamespace()
   
   -- First, compare mainspace parameters.
   if namespace == mw.site.namespaces[0].name and args[cfg.main] then
       return args[cfg.main]
   end
   
   -- Next, compare parameters for non-main namespaces.
   for nsid, ns in pairs( mw.site.namespaces ) do
       local nsname = mw.ustring.lower( ns.name )
       local canonicalName = mw.ustring.lower( ns.canonicalName )
       -- Check the namespace, and ignore main namespace values.
       if nsid ~= 0 and nsname == namespace then
           -- Check local namespace name.
           if args[nsname] then
               return args[nsname]
           -- Check canonical namespace name.
           elseif args[canonicalName] then
               return args[canonicalName]
           else
               -- Check alias names.
               for _, alias in ipairs( ns.aliases ) do
                   local aliasArg = args[ mw.ustring.lower( alias ) ]
                   if aliasArg then
                       return aliasArg
                   end
               end
           end
       end
   end
   
   -- Finally, 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 args[cfg.other] then
       return args[cfg.other]
   end

end

-- Process the arguments. function p.main(frame)

   -- If called via #invoke, use the args passed into the invoking
   -- template, or the args passed to #invoke if any exist. Otherwise
   -- assume args are being passed directly in.
   local origArgs
   if frame == mw.getCurrentFrame() then
       origArgs = frame:getParent().args
       for k, v in pairs( frame.args ) do
           origArgs = frame.args
           break
       end
   else
       origArgs = frame
   end
   
   -- Trim whitespace and remove blank arguments for demospace and 
   -- page parameters.
   for k, v in pairs(origArgs) do
       v = mw.text.trim(v) -- Trim whitespace.
       if k == cfg.demospace or k == cfg.page then
           if v ~=  then
               args[k] = v
           end
       else
           args[k] = v
       end
   end
   
   return compare()

end

-- Create a wikitable of all possible namespace parameters. function p.table()

   -- Start the wikitable.
   local ret = '{| class="wikitable"'
       .. '\n|-'
       .. '\n! ' .. cfg.wikitableNamespaceHeader
       .. '\n! ' .. cfg.wikitableAliasesHeader
   
   -- Generate the row for the main namespace.
   ret = ret .. '\n|-'
       .. '\n| ' .. cfg.main
       .. '\n|'
   
   -- Generate the other wikitable rows.
   for nsid, ns in pairs( mw.site.subjectNamespaces ) do
       if nsid ~= 0 then -- Ignore the main namespace, as it is set in cfg.
           local name = '' .. mw.ustring.lower( ns.name ) .. ''
           local aliases = {}
           if ns.canonicalName ~= ns.name then
               table.insert( aliases, '' .. mw.ustring.lower( ns.canonicalName ) .. '' )
           end
           for _, v in ipairs( ns.aliases ) do
               table.insert( aliases, '' .. mw.ustring.lower(v) .. '' )
           end
           ret = ret .. '\n|-'
               .. '\n| ' .. name
               .. '\n| ' .. table.concat( aliases, ', ' )
       end
   end
   
   -- End the wikitable.
   ret = ret .. '\n|-'
       .. '\n|}'
   
   return ret

end

return p