Modul:Wikidata utilities

Die Dokumentation für dieses Modul kann unter Modul:Wikidata utilities/doc erstellt werden

local fw = {}

function fw.checkId( id ) -- only syntax check
	if ( not id ) or ( type( id ) ~= 'string' ) or ( id == '' ) then
		return ''
	end
	local i = id:upper()
	if mw.ustring.match( i, '^Q[%d]+$') == nil then
		if mw.ustring.match( i, '^[%d]+$') ~= nil then -- only number
			return 'Q' .. i
		else -- invalid id
			return ''
		end
	end
	return i
end

function fw.getEntity( id )
	local wrongQualifier = false
	local entity = nil

	local i = fw.checkId( id )
	if i ~= '' then
		-- expensive function call
		entity = mw.wikibase.getEntity( i )
		if not entity then
			i = ''
			wrongQualifier = true
		end
	else
		if id ~= '' then wrongQualifier = true end
	end
	return i, entity, wrongQualifier
end

local function getFirstValue( statements )
	if #statements == 0 then
		return nil
	end

	for i = 1, #statements, 1 do
		if statements[i].mainsnak.snaktype == 'value' then
			return statements[i].mainsnak.datavalue.value
		end
	end

	return nil
end

local function getNValues( statements, count )
	local ar = {}
	if count > #statements then count = #statements end
	if ( #statements == 0 ) or ( count <= 0 ) then
		return ar
	end

	local i = 0
	repeat
		i = i + 1
		if statements[i].mainsnak.snaktype == 'value' then
			table.insert( ar, statements[i].mainsnak.datavalue.value )
		end
	until ( i >= #statements ) or ( #ar >= count )

	return ar
end

function fw.getStatements( entity, p, count )
	local ar = {}
	if ( not entity ) or ( entity == '' ) then
		return ar
	end

	local statements
	if type( entity ) == 'string' then
		statements = mw.wikibase.getBestStatements( entity, p )
	else
		statements = entity:getBestStatements( p )
	end

	count = count or #statements
	if count > #statements then count = #statements end
	if ( #statements == 0 ) or ( count <= 0 ) then
		return ar
	end

	local i = 0
	repeat
		i = i + 1
		if statements[i].mainsnak.snaktype == 'value' then
			table.insert( ar, statements[i] )
		end
	until ( i >= #statements ) or ( #ar >= count )

	return ar
end

function fw.getValue( entity, p )
	if ( not entity ) or ( entity == '' ) then
		return ''
	end

	local value
	if type( entity ) == 'string' then
		value = getFirstValue( mw.wikibase.getBestStatements( entity, p ) )
	else
		value = getFirstValue( entity:getBestStatements( p ) )
	end
	if value then
		return value
	end

	return ''
end

function fw.getId( entity, p )
	if ( not entity ) or ( entity == '' ) then
		return ''
	end
	
	local value
	if type( entity ) == 'string' then
		value = getFirstValue( mw.wikibase.getBestStatements( entity, p ) )
	else
		value = getFirstValue( entity:getBestStatements( p ) )
	end
	if value then
		return value.id
	end

	return ''
end

function fw.getValues( entity, p, count )
	if ( not entity ) or ( entity == '' ) then
		return ''
	end

	local statements
	if type( entity ) == 'string' then
		statements = mw.wikibase.getBestStatements( entity, p )
	else
		statements = entity:getBestStatements( p )
	end

	return getNValues( statements, count or #statements )
end

function fw.getValuesWithQualifierIds( entity, p, qualifierP, defaultId )
	local result = {}
	local statements = fw.getStatements( entity, p, nil )
	if #statements == 0 then return result end
	-- defaultId is used if a qualifier is missing
	local default = defaultId
	if ( default == nil ) or ( default == '' ) or type( default ) ~= 'string'
		then default = 'unknown' end

	local value, id, i, j
	for i = 1, #statements, 1 do
		value = statements[i].mainsnak.datavalue.value
		id = default
		if statements[i].qualifiers and statements[i].qualifiers[ qualifierP ]
			and ( #statements[i].qualifiers[ qualifierP ] > 0 ) then
			for j = 1, #statements[i].qualifiers[ qualifierP ], 1 do
				if statements[i].qualifiers[ qualifierP ][ j ].snaktype == 'value' then
					id = statements[i].qualifiers[ qualifierP ][ j ].datavalue.value.id
					break
				end
			end
		end
		result[ id ] = value
	end

	return result
end

-- get values array for monolingual text
function fw.getValuesWithLanguages( entity, p )
	local result = {}
	local statements = fw.getStatements( entity, p, nil )
	if #statements == 0 or statements[1].mainsnak.datatype ~= 'monolingualtext'
		then return result end

	local hyphen, i, lng, value
	for i = 1, #statements, 1 do
		value = statements[i].mainsnak.datavalue.value
		lng = value.language
		hyphen = lng:find( '-' )
		if hyphen then
			lng = lng:sub( 1, hyphen - 1 )
		end
		result[ lng ] = value.text
	end

	return result
end

local function getValueFromDatavalue( datavalue )
	local v = datavalue.value
	local t = datavalue.type
	if type( v ) == 'table' then
		-- items which can be reduced to a string
		if t == 'wikibase-entityid' then v = v.id
		elseif t == 'time' then v = v.time
		end
	end
	return v, t
end

-- The following function is an experimental one, not for extensive use
function fw.getValuesWithQualifiers( entity, p, qualifiers, count )
	local result = {}
	local statements = fw.getStatements( entity, p, count )
	if #statements == 0 then return result end

	if qualifiers and ( type( qualifiers ) == 'string' ) then
		qualifiers = { qualifiers }
	end

	local array, key, value, i, j
	for i = 1, #statements, 1 do
		array = { value = statements[i].mainsnak.datavalue.value,
			['value-type'] = statements[i].mainsnak.datavalue.type }
		if statements[i].qualifiers then
			if not qualifiers then -- all qualifier properties
				for key, value in pairs( statements[i].qualifiers ) do
					if #value > 0 then
						for j = 1, #value, 1 do
							if value[ j ].snaktype == 'value' then
								array[ key ], array[ key .. '-type' ] =
									getValueFromDatavalue( value[ j ].datavalue )
								break
							end
						end
					end
				end
			else -- table of selected qualifier properties
				for key, value in pairs( qualifiers ) do
					if statements[i].qualifiers[ value ] and
						( #statements[i].qualifiers[ value ] > 0 ) then
						for j = 1, #statements[i].qualifiers[ value ], 1 do
							if statements[i].qualifiers[ value ][ j ].snaktype == 'value' then
								array[ value ], array[ value .. '-type' ] =
									getValueFromgetValueFromDatavalue( statements[i].qualifiers[ value ][ j ].datavalue )
								break
							end
						end
					end
				end
			end
		end
		table.insert( result, array )
	end
	return result
end

function fw.typeSearch( p31, list, limit )
	-- p31: array of Wikidata values
	-- list: array of q id - types relations
	-- limit: maximum levels to analyse
	if (not p31) or (#p31 == 0) then return 'error' end
	local aType, i, id, j

	for i = 1, #p31, 1 do
		id = p31[i].id
		aType = list[id]

		if aType then
			return aType
		else
			j = 0
			repeat
				id = fw.getId( id, 'P279' )
				if id ~= '' then
					aType = list[id]
					if aType then return aType end
				end
				j = j + 1
			until (j >= limit) or (id == '')
		end
	end
	return 'error'
end

return fw