Module:Args

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

local Arg = {}
Arg.__index = Arg

function Arg.new( value )
  return setmetatable( {
    __value = value
  }, Arg )
end

-- get the Arg node's value, if it has one
function Arg:val()
  return self.__value
end

-- get the values of the Arg node's direct children
-- this is used to re-flatten/unwrap a particular piece of an Arg tree
function Arg:values()
  local vals = {}
  for k, v in pairs( self ) do
    if type( v ) == 'table' and v.val then
      vals[k] = v:val()
    end
  end

  return vals
end

local p = {}

function insertInto( tbl, key, value )
  local first, rest = string.match( key, '^(.-)_(.*)$' )
  local myKey = first or key
  myKey = tonumber( myKey ) or myKey

  -- make sure the node exists
  if not tbl[myKey] then tbl[myKey] = Arg.new() end

  if first then -- this is an internal node so insert children
    insertInto( tbl[myKey], rest, value )
  else -- this is a leaf so set value
    tbl[myKey].__value = value
  end
end

function p.parse( args )
  local parsedArgs = Arg.new()
  for k, v in pairs( args ) do
    insertInto( parsedArgs, k, v )
  end

  return parsedArgs
end

function p.expandInto( args, key, value )
  local first, rest = string.match( key, '^(.-)_(.*)$' )
  local myKey = first or key
  myKey = tonumber( myKey ) or myKey

  if first then -- this is an internal node so insert children
    -- note this will overwrite values in the case of { arg = 'val', arg_sub = 'val' }
    args[myKey] = type( args[myKey] ) == 'table' and args[myKey] or {}
    p.expandInto( args[myKey], rest, value )
  else -- this is a leaf so set value
    args[myKey] = args[myKey] or value -- don't overwrite a table
  end
end

function p.expand( args )
  local expandedArgs = {}
  for k, v in pairs( args ) do
    p.expandInto( expandedArgs, k, v )
  end

  return expandedArgs
end

function p.fromPageContent( content, templateName )
  templateName = templateName or 'Properties'
  local parsedArgs = {}

  local templateContents = string.match( content, '{{%s*' .. templateName .. '%s*|%s*(.-)%s*}}' )

  if templateContents then
    for prop in mw.text.gsplit( templateContents, '%s*|%s*' ) do
      local k, v = unpack( mw.text.split( prop, '%s*=%s*' ) )
      p.expandInto( parsedArgs, k, v )
    end
  end

  return parsedArgs
end

return p