વિભાગ:Namespace detect

--[[

-- --
-- NAMESPACE DETECT --
-- --
-- This module implements the Template: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 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.wikitableNamespaceHeader, 'Namespace')
 local aliasesHeader = checkValue(cfg.wikitableAliasesHeader, '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="wikitable"'
 .. '\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