1 files changed, 138 insertions, 0 deletions
diff --git a/paper/lua-filters/cito/cito.lua b/paper/lua-filters/cito/cito.lua
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+++ b/paper/lua-filters/cito/cito.lua
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+-- Copyright © 2017–2019 Albert Krewinkel, Robert Winkler
+--
+-- This library is free software; you can redistribute it and/or modify it
+-- under the terms of the MIT license. See LICENSE for details.
+
+local _version = '1.0.0'
+local properties_and_aliases = {
+  agrees_with = {
+    'agree_with'
+  },
+  citation = {
+  },
+  cites = {
+  },
+  cites_as_authority = {
+    'as_authority',
+    'authority'
+  },
+  cites_as_data_source = {
+    "as_data_source",
+    "data_source"
+  },
+  cites_as_evidence = {
+    'as_evidence',
+    'evidence'
+  },
+  cites_as_metadata_document = {
+    'as_metadata_document',
+    'metadata_document',
+    'metadata'
+  },
+  cites_as_recommended_reading = {
+    'as_recommended_reading',
+    'recommended_reading'
+  },
+  disagrees_with = {
+    'disagree',
+    'disagrees'
+  },
+  disputes = {
+  },
+  documents = {
+  },
+  extends = {
+  },
+  includes_excerpt_from = {
+    'excerpt',
+    'excerpt_from'
+  },
+  includes_quotation_from = {
+    'quotation',
+    'quotation_from'
+  },
+  obtains_background_from = {
+    'background',
+    'background_from'
+  },
+  refutes = {
+  },
+  replies_to = {
+  },
+  updates = {
+  },
+  uses_data_from = {
+    'data',
+    'data_from'
+  },
+  uses_method_in = {
+    'method',
+    'method_in'
+  },
+}
+
+local default_cito_property = 'citation'
+
+--- Map from cito aliases to the actual cito property.
+local properties_by_alias = {}
+for property, aliases in pairs(properties_and_aliases) do
+  -- every property is an alias for itself
+  properties_by_alias[property] = property
+  for _, alias in pairs(aliases) do
+    properties_by_alias[alias] = property
+  end
+end
+
+--- Split citation ID into cito property and the actual citation ID. If
+--- the ID does not seem to contain a CiTO property, the
+--- `default_cito_property` will be returned, together with the
+--- unchanged input ID.
+local function split_cito_from_id (citation_id)
+  local pattern = '^(.+):(.+)$'
+  local prop_alias, split_citation_id = citation_id:match(pattern)
+
+  if properties_by_alias[prop_alias] then
+    return properties_by_alias[prop_alias], split_citation_id
+  end
+
+  return default_cito_property, citation_id
+end
+
+--- Citations by CiTO properties.
+local function store_cito (cito_cites, prop, cite_id)
+  if not prop then
+    return
+  end
+  if not cito_cites[prop] then
+    cito_cites[prop] = {}
+  end
+  table.insert(cito_cites[prop], cite_id)
+end
+
+--- Returns a Cite filter function which extracts CiTO information and
+--- add it to the given collection table.
+local function extract_cito (cito_cites)
+  return function (cite)
+    for k, citation in pairs(cite.citations) do
+      local cito_prop, cite_id = split_cito_from_id(citation.id)
+      store_cito(cito_cites, cito_prop, cite_id)
+      citation.id = cite_id
+    end
+    return cite
+  end
+end
+
+--- Lists of citation IDs, indexed by CiTO properties.
+local citations_by_property = {}
+
+return {
+  {
+    Cite = extract_cito(citations_by_property)
+  },
+  {
+    Meta = function (meta)
+      meta.cito_cites = citations_by_property
+      return meta
+    end
+  }
+}