--[[
ScholarlyMeta – normalize author/affiliation meta variables
Copyright (c) 2017-2021 Albert Krewinkel, Robert Winkler
Permission to use, copy, modify, and/or distribute this software for any purpose
with or without fee is hereby granted, provided that the above copyright notice
and this permission notice appear in all copies.
THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
THIS SOFTWARE.
]]
local List = require 'pandoc.List'
--- Returns the type of a metadata value.
--
-- @param v a metadata value
-- @treturn string one of `Blocks`, `Inlines`, `List`, `Map`, `string`, `boolean`
local function metatype (v)
if PANDOC_VERSION[1] <= 2 and PANDOC_VERSION[2] <= 16 then
local metatag = type(v) == 'table' and v.t and v.t:gsub('^Meta', '')
return metatag and metatag ~= 'Map' and metatag or type(v)
end
return pandoc.utils.type(v)
end
local type = pandoc.utils.type or metatype
-- Split a string at commas.
local function comma_separated_values(str)
local acc = List:new{}
for substr in str:gmatch('([^,]*)') do
acc[#acc + 1] = substr:gsub('^%s*', ''):gsub('%s*$', '') -- trim
end
return acc
end
--- Ensure the return value is a list.
local function ensure_list (val)
if type(val) == 'List' then
return val
elseif type(val) == 'Inlines' then
-- check if this is really a comma-separated list
local csv = comma_separated_values(pandoc.utils.stringify(val))
if #csv >= 2 then
return csv
end
return List:new{val}
elseif type(val) == 'table' and #val > 0 then
return List:new(val)
else
-- Anything else, use as a singleton (or empty list if val == nil).
return List:new{val}
end
end
--- Returns a function which checks whether an object has the given ID.
local function has_id (id)
return function(x) return x.id == id end
end
--- Copy all key-value pairs of the first table into the second iff there is no
-- such key yet in the second table.
-- @returns the second argument
function add_missing_entries(a, b)
for k, v in pairs(a) do
b[k] = b[k] or v
end
return b
end
--- Create an object with a name. The name is either taken directly from the
-- `name` field, or from the *only* field name (i.e., key) if the object is a
-- dictionary with just one entry. If neither exists, the name is left unset
-- (`nil`).
function to_named_object (obj)
local named = {}
if type(obj) == 'Inlines' then
-- Treat inlines as the name
named.name = obj
named.id = pandoc.utils.stringify(obj)
elseif type(obj) ~= 'table' then
-- if the object isn't a table, just use its value as a name.
named.name = pandoc.MetaInlines{pandoc.Str(tostring(obj))}
named.id = tostring(obj)
elseif obj.name ~= nil then
-- object has name attribute → just create a copy of the object
add_missing_entries(obj, named)
named.id = pandoc.utils.stringify(named.id or named.name)
elseif next(obj) and next(obj, next(obj)) == nil then
-- Single-entry table. The entry's key is taken as the name, the value
-- contains the attributes.
key, attribs = next(obj)
if type(attribs) == 'string' or type(attribs) == 'Inlines' then
named.name = attribs
else
add_missing_entries(attribs, named)
named.name = named.name or pandoc.MetaInlines{pandoc.Str(tostring(key))}
end
named.id = named.id and pandoc.utils.stringify(named.id) or key
else
-- this is not a named object adhering to the usual conventions.
error('not a named object: ' .. tostring(obj))
end
return named
end
--- Resolve institute placeholders to full named objects
local function resolve_institutes (institute, known_institutes)
local unresolved_institutes
if institute == nil then
unresolved_institutes = {}
elseif type(institute) == "string" or type(institute) == "number" then
unresolved_institutes = {institute}
else
unresolved_institutes = institute
end
local result = List:new{}
for i, inst in ipairs(unresolved_institutes) do
result[i] =
known_institutes[tonumber(inst)] or
known_institutes:find_if(has_id(pandoc.utils.stringify(inst))) or
to_named_object(inst)
end
return result
end
--- Insert a named object into a list; if an object of the same name exists
-- already, add all properties only present in the new object to the existing
-- item.
function merge_on_id (list, namedObj)
local elem, idx = list:find_if(has_id(namedObj.id))
local res = elem and add_missing_entries(namedObj, elem) or namedObj
local obj_idx = idx or (#list + 1)
-- return res, obj_idx
list[obj_idx] = res
return res, #list
end
--- Flatten a list of lists.
local function flatten (lists)
local result = List:new{}
for _, lst in ipairs(lists) do
result:extend(lst)
end
return result
end
--- Canonicalize authors and institutes
local function canonicalize(raw_author, raw_institute)
local institutes = ensure_list(raw_institute):map(to_named_object)
local authors = ensure_list(raw_author):map(to_named_object)
for _, author in ipairs(authors) do
author.institute = resolve_institutes(
ensure_list(author.institute),
institutes
)
end
-- Merge institutes defined in author objects with those defined in the
-- top-level list.
local author_insts = flatten(authors:map(function(x) return x.institute end))
for _, inst in ipairs(author_insts) do
merge_on_id(institutes, inst)
end
-- Add list indices to institutes for numbering and reference purposes
for idx, inst in ipairs(institutes) do
inst.index = pandoc.MetaInlines{pandoc.Str(tostring(idx))}
end
-- replace institutes with their indices
local to_index = function (inst)
return tostring(select(2, institutes:find_if(has_id(inst.id))))
end
for _, author in ipairs(authors) do
author.institute = pandoc.MetaList(author.institute:map(to_index))
end
return authors, institutes
end
return {
{
Meta = function(meta)
meta.author, meta.institute = canonicalize(meta.author, meta.institute)
return meta
end
}
}
