Disentangle CiteEngines and Modules

These two are different beasts and thus should be handled differently.

lib/Makefile.am

@@ -2107,7 +2107,6 @@ dist_layouts_DATA =\
 	layouts/arab-article.layout \
 	layouts/article.layout \
 	layouts/article-beamer.layout \
-	layouts/basic.module \
 	layouts/beamer.layout \
 	layouts/beamerposter.layout \
 	layouts/bicaption.module \
@@ -2185,7 +2184,6 @@ dist_layouts_DATA =\
 	layouts/jsarticle.layout \
 	layouts/jsbook.layout \
 	layouts/jss.layout \
-	layouts/jurabib.module \
 	layouts/kluwer.layout \
 	layouts/knitr.module \
 	layouts/latex8.layout \
@@ -2205,7 +2203,6 @@ dist_layouts_DATA =\
 	layouts/mwart.layout \
 	layouts/mwbk.layout \
 	layouts/mwrep.layout \
-	layouts/natbib.module \
 	layouts/natbibapa.module \
 	layouts/noweb.module \
 	layouts/numarticle.inc \
@@ -2302,6 +2299,12 @@ dist_layouts_DATA =\
 	layouts/tufte-handout.layout \
 	layouts/varwidth.module
 
+citeenginesdir = $(pkgdatadir)/citeengines
+dist_citeengines_DATA = \
+	citeengines/basic.citeengine \
+        citeengines/jurabib.citeengine \
+        citeengines/natbib.citeengine
+
 scriptsdir = $(pkgdatadir)/scripts
 dist_scripts_DATA = \
 	scripts/bash_completion \

lib/chkconfig.ltx

@@ -492,6 +492,7 @@
 % configure script.
 \input{chklayouts}
 \input{chkmodules}
+\input{chkciteengines}
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %%%%% END ACTUAL CONFIGURATION INSPECTION CODE %%%%%%%%%%%%%%%%%%%%%%%%%%%%

lib/citeengines/basic.citeengine

@@ -1,9 +1,8 @@
-# \DeclareLyXModule{Default (basic)}
+# \DeclareLyXCiteEngine{BibTeX (basic)}
 # DescriptionBegin
 #   Use the basic citation capabilities provided by plain LaTeX.
 # DescriptionEnd
 # Excludes: jurabib | natbib
-# Category: Citation engine
 
 # Author: Julien Rioux <jrioux@lyx.org>
 

lib/citeengines/jurabib.citeengine

@@ -1,11 +1,10 @@
-# \DeclareLyXModule[jurabib.sty]{Jurabib}
+# \DeclareLyXCiteEngine[jurabib.sty]{Jurabib}
 # DescriptionBegin
 #   Loads the LaTeX package jurabib, a citation engine. Jurabib supports annotations,
 #   author-year style citations and hyphenation patterns for bibliography entries in
 #   English, German, French, Dutch, Spanish and Italian.
 # DescriptionEnd
 # Excludes: basic | natbib
-# Category: Citation engine
 
 # Author: Julien Rioux <jrioux@lyx.org>
 

lib/citeengines/natbib.citeengine

@@ -1,4 +1,4 @@
-# \DeclareLyXModule[natbib.sty]{Natbib}
+# \DeclareLyXCiteEngine[natbib.sty]{Natbib}
 # DescriptionBegin
 #   Loads the LaTeX package natbib, a citation engine. Natbib supports
 #   both author-year and numerical styles for citations, automatic sorting
@@ -6,7 +6,6 @@
 #   `van' part of author names, shortened and full author lists, and more.
 # DescriptionEnd
 # Excludes: basic | jurabib
-# Category: Citation engine
 
 # Author: Julien Rioux <jrioux@lyx.org>
 

lib/configure.py

@@ -1502,6 +1502,132 @@ def processModuleFile(file, filename, bool_docbook):
     return '"%s" "%s" "%s" "%s" "%s" "%s" "%s"\n' % (modname, filename, desc, pkgs, req, excl, catgy)
 
 
+def checkCiteEnginesConfig():
+  removeFiles(['lyxciteengines.lst', 'chkciteengines.tex'])
+
+  logger.info('+checking list of cite engines... ')
+  tx = open('lyxciteengines.lst', 'w')
+  tx.write('''## This file declares cite engines and their associated definition files.
+## It has been automatically generated by configure
+## Use "Options/Reconfigure" if you need to update it after a
+## configuration change.
+## "CiteEngineName" "filename" "CiteEngineType" "Description" "Packages" "Requires" "Excludes"
+''')
+
+  # build the list of available modules
+  seen = []
+  # note that this searches the local directory first, then the
+  # system directory. that way, we pick up the user's version first.
+  for file in glob.glob( os.path.join('citeengines', '*.citeengine') ) + \
+      glob.glob( os.path.join(srcdir, 'citeengines', '*.citeengine' ) ) :
+      # valid file?
+      logger.info(file)
+      if not os.path.isfile(file):
+          continue
+
+      filename = file.split(os.sep)[-1]
+      filename = filename[:-11]
+      if seen.count(filename):
+          continue
+
+      seen.append(filename)
+      retval = processCiteEngineFile(file, filename, bool_docbook)
+      if retval != "":
+          tx.write(retval)
+  tx.close()
+  logger.info('\tdone')
+
+
+def processCiteEngineFile(file, filename, bool_docbook):
+    ''' process cite engines file and get a line of result
+
+        The top of a cite engine file should look like this:
+          #\DeclareLyXCiteEngine[LaTeX Packages]{CiteEngineName}
+          #DescriptionBegin
+          #...body of description...
+          #DescriptionEnd
+          #Requires: [list of required engines]
+          #Excludes: [list of excluded engines]
+        The last two lines are optional.
+        We expect output:
+          "CiteEngineName" "filename" "CiteEngineType" "Description" "Packages" "Requires" "Excludes"
+    '''
+    remods = re.compile(r'\DeclareLyXCiteEngine\s*(?:\[([^]]*?)\])?{(.*)}')
+    rereqs = re.compile(r'#+\s*Requires: (.*)')
+    reexcs = re.compile(r'#+\s*Excludes: (.*)')
+    redbeg = re.compile(r'#+\s*DescriptionBegin\s*$')
+    redend = re.compile(r'#+\s*DescriptionEnd\s*$')
+    recet = re.compile(r'\s*CiteEngineType (.*)')
+
+    modname = desc = pkgs = req = excl = cet = ""
+    readingDescription = False
+    descLines = []
+
+    for line in open(file).readlines():
+      if readingDescription:
+        res = redend.search(line)
+        if res != None:
+          readingDescription = False
+          desc = " ".join(descLines)
+          # Escape quotes.
+          desc = desc.replace('"', '\\"')
+          continue
+        descLines.append(line[1:].strip())
+        continue
+      res = redbeg.search(line)
+      if res != None:
+        readingDescription = True
+        continue
+      res = remods.search(line)
+      if res != None:
+          (pkgs, modname) = res.groups()
+          if pkgs == None:
+            pkgs = ""
+          else:
+            tmp = [s.strip() for s in pkgs.split(",")]
+            pkgs = ",".join(tmp)
+          continue
+      res = rereqs.search(line)
+      if res != None:
+        req = res.group(1)
+        tmp = [s.strip() for s in req.split("|")]
+        req = "|".join(tmp)
+        continue
+      res = reexcs.search(line)
+      if res != None:
+        excl = res.group(1)
+        tmp = [s.strip() for s in excl.split("|")]
+        excl = "|".join(tmp)
+        continue
+      res = recet.search(line)
+      if res != None:
+        cet = res.group(1)
+        continue
+
+    if modname == "":
+      logger.warning("Cite Engine File file without \DeclareLyXCiteEngine line. ")
+      return ""
+
+    if pkgs != "":
+        # this cite engine has some latex dependencies:
+        # append the dependencies to chkciteengines.tex,
+        # which is \input'ed by chkconfig.ltx
+        testpackages = list()
+        for pkg in pkgs.split(","):
+            if "->" in pkg:
+                # this is a converter dependency: skip
+                continue
+            if pkg.endswith(".sty"):
+                pkg = pkg[:-4]
+            testpackages.append("\\TestPackage{%s}" % (pkg,))
+        cm = open('chkciteengines.tex', 'a')
+        for line in testpackages:
+            cm.write(line + '\n')
+        cm.close()
+
+    return '"%s" "%s" "%s" "%s" "%s" "%s" "%s"\n' % (modname, filename, cet, desc, pkgs, req, excl)
+
+
 def checkTeXAllowSpaces():
     ''' Let's check whether spaces are allowed in TeX file names '''
     tex_allows_spaces = 'false'
@@ -1543,8 +1669,8 @@ def removeTempFiles():
     # Final clean-up
     if not lyx_keep_temps:
         removeFiles(['chkconfig.vars', 'chklatex.ltx', 'chklatex.log',
-            'chklayouts.tex', 'chkmodules.tex', 'missfont.log',
-            'wrap_chkconfig.ltx', 'wrap_chkconfig.log'])
+            'chklayouts.tex', 'chkmodules.tex', 'chkciteengines.tex',
+            'missfont.log', 'wrap_chkconfig.ltx', 'wrap_chkconfig.log'])
 
 
 if __name__ == '__main__':
@@ -1623,6 +1749,7 @@ Format %i
     if lyx_kpsewhich:
         rescanTeXFiles()
     checkModulesConfig()
+    checkCiteEnginesConfig()
     # --without-latex-config can disable lyx_check_config
     ret = checkLatexConfig(lyx_check_config and LATEX != '', bool_docbook)
     removeTempFiles()

po/Rules-lyx

@@ -34,7 +34,7 @@ layouts_l10n.pot: $(top_srcdir)/lib/layouts/*.layout \
 # Read translatable strings from layouts and translations from the po files and
 # create the layouttranslations file containing all LaTeX relevant translations
 $(top_srcdir)/lib/layouttranslations: $(POFILES) $(top_srcdir)/lib/layouts/*.layout \
-                $(top_srcdir)/lib/layouts/*.inc $(top_srcdir)/lib/layouts/*.module
+                $(top_srcdir)/lib/layouts/*.inc $(top_srcdir)/lib/layouts/*.module $(top_srcdir)/lib/citeengines/*.citeengines
 	$(LYX_POT) -o $@ -t layouttranslations ${top_srcdir}/lib/layouts/*.layout ${top_srcdir}/lib/layouts/*.inc ${top_srcdir}/lib/layouts/*.module
 
 languages_l10n.pot: $(top_srcdir)/lib/languages

po/lyx_pot.py

@@ -91,6 +91,7 @@ def layouts_l10n(input_files, output, base, layouttranslations):
     ListName = re.compile(r'^\s*ListName\s+(.*\S)\s*$', re.IGNORECASE)
     CategoryName = re.compile(r'^\s*Category\s+(.*\S)\s*$', re.IGNORECASE)
     NameRE = re.compile(r'^\s*#\s*\\DeclareLyXModule.*{(.*)}$', re.IGNORECASE)
+    CiteNameRE = re.compile(r'^\s*#\s*\\DeclareLyXCiteEngine.*{(.*)}$', re.IGNORECASE)
     InsetLayout = re.compile(r'^InsetLayout\s+\"?(.*)\"?\s*$', re.IGNORECASE)
     FlexCheck = re.compile(r'^Flex:(.*)', re.IGNORECASE)
     CaptionCheck = re.compile(r'^Caption:(.*)', re.IGNORECASE)
@@ -229,6 +230,12 @@ def layouts_l10n(input_files, output, base, layouttranslations):
                 readingI18nPreamble = True
                 continue
             res = NameRE.search(line)
+            if res != None:
+                string = res.group(1)
+                if not layouttranslations:
+                    writeString(out, src, base, lineno + 1, string)
+                continue
+            res = CiteNameRE.search(line)
             if res != None:
                 string = res.group(1)
                 if not layouttranslations:

src/BufferParams.cpp

@@ -2333,6 +2333,7 @@ void BufferParams::makeDocumentClass(bool const clone)
 
 	invalidateConverterCache();
 	LayoutModuleList mods;
+	LayoutModuleList ces;
 	LayoutModuleList::iterator it = layout_modules_.begin();
 	LayoutModuleList::iterator en = layout_modules_.end();
 	for (; it != en; ++it)
@@ -2341,9 +2342,9 @@ void BufferParams::makeDocumentClass(bool const clone)
 	it = cite_engine_.begin();
 	en = cite_engine_.end();
 	for (; it != en; ++it)
-		mods.push_back(*it);
+		ces.push_back(*it);
 
-	doc_class_ = getDocumentClass(*baseClass(), mods, clone);
+	doc_class_ = getDocumentClass(*baseClass(), mods, ces, clone);
 
 	TextClass::ReturnValues success = TextClass::OK;
 	if (!forced_local_layout_.empty())

src/CiteEnginesList.cpp

@@ -0,0 +1,280 @@
+// -*- C++ -*-
+/**
+ * \file CiteEnginesList.cpp
+ * This file is part of LyX, the document processor.
+ * Licence details can be found in the file COPYING.
+ *
+ * \author Richard Heck
+ * \author Jürgen Spitzmüller
+ *
+ * Full author contact details are available in file CREDITS.
+ */
+
+#include <config.h>
+
+#include "CiteEnginesList.h"
+
+#include "LaTeXFeatures.h"
+#include "Lexer.h"
+
+#include "support/debug.h"
+#include "support/FileName.h"
+#include "support/gettext.h"
+#include "support/filetools.h"
+#include "support/lstrings.h"
+
+#include <algorithm>
+
+using namespace std;
+using namespace lyx::support;
+
+namespace lyx {
+
+
+//global variable: cite engine list
+CiteEnginesList theCiteEnginesList;
+
+
+LyXCiteEngine::LyXCiteEngine(string const & n, string const & i,
+			     vector<string> const & cet, string const & d,
+			     vector<string> const & p,
+			     vector<string> const & r, vector<string> const & e):
+	name_(n), id_(i), engine_types_(cet), description_(d), package_list_(p),
+	required_engines_(r), excluded_engines_(e),
+	checked_(false), available_(false)
+{
+	filename_ = id_ + ".citeengine";
+}
+
+
+vector<string> LyXCiteEngine::prerequisites() const
+{
+	if (!checked_)
+		isAvailable();
+	return prerequisites_;
+}
+
+
+bool LyXCiteEngine::isAvailable() const
+{
+	if (package_list_.empty())
+		return true;
+	if (checked_)
+		return available_;
+	checked_ = true;
+	available_ = true;
+	//check whether all of the required packages are available
+	vector<string>::const_iterator it  = package_list_.begin();
+	vector<string>::const_iterator end = package_list_.end();
+	for (; it != end; ++it) {
+		if (!LaTeXFeatures::isAvailable(*it)) {
+			available_ = false;
+			prerequisites_.push_back(*it);
+		}
+	}
+	return available_;
+}
+
+
+bool LyXCiteEngine::isCompatible(string const & cename) const
+{
+	// do we exclude it?
+	if (find(excluded_engines_.begin(), excluded_engines_.end(), cename) !=
+			excluded_engines_.end())
+		return false;
+
+	LyXCiteEngine const * const lm = theCiteEnginesList[cename];
+	if (!lm)
+		return true;
+
+	// does it exclude us?
+	vector<string> const excengs = lm->getExcludedEngines();
+	if (find(excengs.begin(), excengs.end(), id_) != excengs.end())
+		return false;
+
+	return true;
+}
+
+
+bool LyXCiteEngine::areCompatible(string const & eng1, string const & eng2)
+{
+	LyXCiteEngine const * const lm1 = theCiteEnginesList[eng1];
+	if (lm1)
+		return lm1->isCompatible(eng2);
+	LyXCiteEngine const * const lm2 = theCiteEnginesList[eng2];
+	if (lm2)
+		return lm2->isCompatible(eng1);
+	// Can't check it either way.
+	return true;
+}
+
+
+// used when sorting the cite engine list.
+class EngineSorter {
+public:
+	int operator()(LyXCiteEngine const & ce1, LyXCiteEngine const & ce2) const
+	{
+		return _(ce1.getName()) < _(ce2.getName());
+	}
+};
+
+
+// Much of this is borrowed from LayoutFileList::read()
+bool CiteEnginesList::read()
+{
+	FileName const real_file = libFileSearch("", "lyxciteengines.lst");
+	LYXERR(Debug::TCLASS, "Reading cite engines from `" << real_file << '\'');
+
+	if (real_file.empty()) {
+		LYXERR0("unable to find cite engines file `citeengines.lst'.\n"
+			<< "No cite engines will be available.");
+		return false;
+	}
+
+	Lexer lex;
+	if (!lex.setFile(real_file)) {
+		LYXERR0("lyxlex was not able to set file: "
+			<< real_file << ".\nNo cite engines will be available.");
+		return false;
+	}
+
+	if (!lex.isOK()) {
+		LYXERR0("unable to open cite engines file  `"
+			<< to_utf8(makeDisplayPath(real_file.absFileName(), 1000))
+			<< "'\nNo cite engines will be available.");
+		return false;
+	}
+
+	bool finished = false;
+	// Parse cite engines files
+	LYXERR(Debug::TCLASS, "Starting parsing of lyxciteengines.lst");
+	while (lex.isOK() && !finished) {
+		LYXERR(Debug::TCLASS, "\tline by line");
+		switch (lex.lex()) {
+		case Lexer::LEX_FEOF:
+			finished = true;
+			break;
+		default:
+			string const cename = lex.getString();
+			LYXERR(Debug::TCLASS, "Engine name: " << cename);
+			if (!lex.next())
+				break;
+			string const fname = lex.getString();
+			LYXERR(Debug::TCLASS, "Filename: " << fname);
+			if (!lex.next(true))
+				break;
+			string cet = lex.getString();
+			LYXERR(Debug::TCLASS, "Engine Type: " << cet);
+			vector<string> cets;
+			while (!cet.empty()) {
+				string p;
+				cet = split(cet, p, '|');
+				cets.push_back(p);
+			}
+			if (!lex.next(true))
+				break;
+			string const desc = lex.getString();
+			LYXERR(Debug::TCLASS, "Description: " << desc);
+			//FIXME Add packages
+			if (!lex.next())
+				break;
+			string str = lex.getString();
+			LYXERR(Debug::TCLASS, "Packages: " << str);
+			vector<string> pkgs;
+			while (!str.empty()) {
+				string p;
+				str = split(str, p, ',');
+				pkgs.push_back(p);
+			}
+			if (!lex.next())
+				break;
+			str = lex.getString();
+			LYXERR(Debug::TCLASS, "Required: " << str);
+			vector<string> req;
+			while (!str.empty()) {
+				string p;
+				str = split(str, p, '|');
+				req.push_back(p);
+			}
+			if (!lex.next())
+				break;
+			str = lex.getString();
+			LYXERR(Debug::TCLASS, "Excluded: " << str);
+			vector<string> exc;
+			while (!str.empty()) {
+				string p;
+				str = split(str, p, '|');
+				exc.push_back(p);
+			}
+			// This code is run when we have
+			// cename, fname, desc, pkgs, req and exc
+			addCiteEngine(cename, fname, cets, desc, pkgs, req, exc);
+		} // end switch
+	} //end while
+
+	LYXERR(Debug::TCLASS, "End of parsing of lyxciteengines.lst");
+
+	if (!theCiteEnginesList.empty())
+		sort(theCiteEnginesList.begin(), theCiteEnginesList.end(), EngineSorter());
+	return true;
+}
+
+
+void CiteEnginesList::addCiteEngine(string const & cename,
+	string const & filename, vector<string> const & cets, string const & description,
+	vector<string> const & pkgs, vector<string> const & req,
+	vector<string> const & exc)
+{
+	LyXCiteEngine ce(cename, filename, cets, description, pkgs, req, exc);
+	englist_.push_back(ce);
+}
+
+
+LyXCiteEnginesList::const_iterator CiteEnginesList::begin() const
+{
+	return englist_.begin();
+}
+
+
+LyXCiteEnginesList::iterator CiteEnginesList::begin()
+{
+	return englist_.begin();
+}
+
+
+LyXCiteEnginesList::const_iterator CiteEnginesList::end() const
+{
+	return englist_.end();
+}
+
+
+LyXCiteEnginesList::iterator CiteEnginesList::end()
+{
+	return englist_.end();
+}
+
+
+LyXCiteEngine const * CiteEnginesList::operator[](string const & str) const
+{
+	LyXCiteEnginesList::const_iterator it = englist_.begin();
+	for (; it != englist_.end(); ++it)
+		if (it->getID() == str) {
+			LyXCiteEngine const & eng = *it;
+			return &eng;
+		}
+	return 0;
+}
+
+
+LyXCiteEngine * CiteEnginesList::operator[](string const & str)
+{
+	LyXCiteEnginesList::iterator it = englist_.begin();
+	for (; it != englist_.end(); ++it)
+		if (it->getID() == str) {
+			LyXCiteEngine & eng = *it;
+			return &eng;
+		}
+	return 0;
+}
+
+} // namespace lyx

src/CiteEnginesList.h

@@ -0,0 +1,156 @@
+// -*- C++ -*-
+/**
+ * \file CiteEnginesList.h
+ * This file is part of LyX, the document processor.
+ * Licence details can be found in the file COPYING.
+ *
+ * \author Richard Heck
+ * \author Jürgen Spitzmüller
+ *
+ * Full author contact details are available in file CREDITS.
+ */
+
+#ifndef CITEENGINESLIST_H
+#define CITEENGINESLIST_H
+
+#include <string>
+#include <vector>
+
+namespace lyx {
+
+/**
+ *  This class represents a particular LyX "cite engine", which defines the features
+ * of a particular citation backend such as natbib or biblatex. In that sense, it is more like
+ *  a LaTeX package, where a layout file corresponds to a LaTeX class.
+ *
+ *  In general, a given cite engine can be used with any document class. That said,
+ *  one cite engine may `require' another, or it may `exclude' some other cite engine.
+ *  The requires and excludes are given in comments within the cite engine file,
+ *  which must begin roughly so:
+ *  # \DeclareLyXCiteEngine[natbib.sty]{Natbib}
+ *  # DescriptionBegin
+ *  #   Loads the LaTeX package natbib, a citation engine. Natbib supports
+ *  #   both author-year and numerical styles for citations, automatic sorting
+ *  #   and merging of numerical citations, annotations, capitalization of the
+ *  #   `van' part of author names, shortened and full author lists, and more.
+ *  # DescriptionEnd
+ *  # Excludes: basic | jurabib
+ *  The description might be used in the gui to give information to the user. The
+ *  Requires and Excludes lines are read by the configuration script
+ *  and written to a file citeengines.lst in the user configuration directory.
+ *  That file is then read on startup to populate the CiteEnginesList, below.
+ *
+ *  Engines can also be "provided" or "excluded" by document classes, using
+ *  the ProvidesEngine and ExcludesEngine tags.
+ */
+
+class LyXCiteEngine {
+public:
+	///
+	LyXCiteEngine(std::string const & name, std::string const & id,
+		      std::vector<std::string> const & enginetypes,
+		      std::string const & description,
+		      std::vector<std::string> const & packagelist,
+		      std::vector<std::string> const & requires,
+		      std::vector<std::string> const & excludes);
+	/// whether the required packages are available
+	bool isAvailable() const;
+	/// the missing prerequisites, if any
+	std::vector<std::string> prerequisites() const;
+	///
+	std::string const & getName() const { return name_; }
+	///
+	std::string const & getID() const { return id_; }
+	///
+	std::string const & getFilename() const { return filename_; }
+	///
+	std::vector<std::string> const & getEngineType() const { return engine_types_; }
+	///
+	std::string const & getDescription() const { return description_; }
+	///
+	std::vector<std::string> const & getPackageList() const
+		{ return package_list_; }
+	///
+	std::vector<std::string> const & getRequiredEngines() const
+		{ return required_engines_; }
+	/// Engines this one excludes: the list should be treated disjunctively
+	std::vector<std::string> const & getExcludedEngines() const
+		{ return excluded_engines_; }
+	/// \return true if the engine is compatible with this one, i.e.,
+	/// it does not exclude us and we do not exclude it.
+	/// this will also return true if cename is unknown and we do not
+	/// exclude it, since in that case we cannot check its exclusions.
+	bool isCompatible(std::string const & cename) const;
+	///
+	static bool areCompatible(std::string const & eng1, std::string const & eng2);
+private:
+	/// what appears in the ui
+	std::string name_;
+	/// the engine's unique identifier
+	/// at present, this is the filename, without the extension
+	std::string id_;
+	/// the filename
+	std::string filename_;
+	/// the engine type(s)
+	std::vector<std::string> engine_types_;
+	/// a short description for use in the ui
+	std::string description_;
+	/// the LaTeX packages on which this depends, if any
+	std::vector<std::string> package_list_;
+	/// Engines this one requires: at least one
+	std::vector<std::string> required_engines_;
+	/// Engines this one excludes: none of these
+	std::vector<std::string> excluded_engines_;
+	// these are mutable because they are used to cache the results
+	// or an otherwise const operation.
+	///
+	mutable bool checked_;
+	///
+	mutable bool available_;
+	///
+	mutable std::vector<std::string> prerequisites_;
+};
+
+typedef std::vector<LyXCiteEngine> LyXCiteEnginesList;
+
+/**
+ *  The CiteEnginesList represents the various LyXCiteEngine's that are available at
+ *  present.
+ */
+class CiteEnginesList {
+public:
+	///
+	CiteEnginesList() {}
+	/// reads the engines from a file generated by configure.py
+	bool read();
+	///
+	LyXCiteEnginesList::const_iterator begin() const;
+	///
+	LyXCiteEnginesList::iterator begin();
+	///
+	LyXCiteEnginesList::const_iterator end() const;
+	///
+	LyXCiteEnginesList::iterator end();
+	///
+	bool empty() const { return englist_.empty(); }
+	/// Returns a pointer to the LyXCiteEngine with filename str.
+	/// Returns a null pointer if no such engine is found.
+	LyXCiteEngine const * operator[](std::string const & str) const;
+	///
+	LyXCiteEngine * operator[](std::string const & str);
+	private:
+	/// noncopyable
+	CiteEnginesList(CiteEnginesList const &);
+	///
+	void operator=(CiteEnginesList const &);
+	/// add an engine to the list
+	void addCiteEngine(std::string const &, std::string const &,
+		std::vector<std::string> const &, std::string const &, std::vector<std::string> const &,
+		std::vector<std::string> const &, std::vector<std::string> const &);
+	///
+	std::vector<LyXCiteEngine> englist_;
+};
+
+extern CiteEnginesList theCiteEnginesList;
+}
+#endif

src/LyX.cpp

@@ -22,6 +22,7 @@
 #include "Buffer.h"
 #include "BufferList.h"
 #include "CmdDef.h"
+#include "CiteEnginesList.h"
 #include "ColorSet.h"
 #include "ConverterCache.h"
 #include "Converter.h"
@@ -935,8 +936,10 @@ bool LyX::init()
 	LYXERR(Debug::INIT, "Reading layouts...");
 	// Load the layouts
 	LayoutFileList::get().read();
-	//...and the modules
+	//... the modules
 	theModuleList.read();
+	//... and the cite engines
+	theCiteEnginesList.read();
 
 	// read keymap and ui files in batch mode as well
 	// because InsetInfo needs to know these to produce
@@ -1020,7 +1023,8 @@ bool LyX::queryUserLyXDir(bool explicit_userdir)
 		return configFileNeedsUpdate("lyxrc.defaults")
 			|| configFileNeedsUpdate("lyxmodules.lst")
 			|| configFileNeedsUpdate("textclass.lst")
-			|| configFileNeedsUpdate("packages.lst");
+			|| configFileNeedsUpdate("packages.lst")
+			|| configFileNeedsUpdate("lyxciteengines.lst");
 	}
 
 	first_start = !explicit_userdir;

src/Makefile.am

@@ -108,6 +108,7 @@ SOURCEFILESCORE = \
 	Bullet.cpp \
 	Changes.cpp \
 	Chktex.cpp \
+	CiteEnginesList.cpp \
 	CmdDef.cpp \
 	Color.cpp \
 	ConverterCache.cpp \
@@ -201,6 +202,7 @@ HEADERFILESCORE = \
 	BufferView.h \
 	Bullet.h \
 	Citation.h \
+	CiteEnginesList.h \
 	Changes.h \
 	Chktex.h \
 	CmdDef.h \

src/TextClass.cpp

@@ -17,6 +17,7 @@
 #include "TextClass.h"
 
 #include "LayoutFile.h"
+#include "CiteEnginesList.h"
 #include "Color.h"
 #include "Counters.h"
 #include "Floating.h"
@@ -123,6 +124,8 @@ string translateReadType(TextClass::ReadType rt)
 		return "input file";
 	case TextClass::MODULE:
 		return "module file";
+	case TextClass::CITE_ENGINE:
+		return "cite engine";
 	case TextClass::VALIDATION:
 		return "validation";
 	}
@@ -1585,6 +1588,7 @@ Layout TextClass::createBasicLayout(docstring const & name, bool unknown) const
 
 DocumentClassPtr getDocumentClass(
 		LayoutFile const & baseClass, LayoutModuleList const & modlist,
+		LayoutModuleList const & celist,
 		bool const clone)
 {
 	DocumentClassPtr doc_class =
@@ -1623,6 +1627,42 @@ DocumentClassPtr getDocumentClass(
 			frontend::Alert::warning(_("Read Error"), msg);
 		}
 	}
+
+	LayoutModuleList::const_iterator cit = celist.begin();
+	LayoutModuleList::const_iterator cen = celist.end();
+	for (; cit != cen; ++cit) {
+		string const ceName = *cit;
+		LyXCiteEngine * ce = theCiteEnginesList[ceName];
+		if (!ce) {
+			docstring const msg =
+						bformat(_("The cite engine %1$s has been requested by\n"
+						"this document but has not been found in the list of\n"
+						"available engines. If you recently installed it, you\n"
+						"probably need to reconfigure LyX.\n"), from_utf8(ceName));
+			if (!clone)
+				frontend::Alert::warning(_("Cite Engine not available"), msg);
+			continue;
+		}
+		if (!ce->isAvailable() && !clone) {
+			docstring const prereqs = from_utf8(getStringFromVector(ce->prerequisites(), "\n\t"));
+			docstring const msg =
+				bformat(_("The cite engine %1$s requires a package that is not\n"
+					"available in your LaTeX installation, or a converter that\n"
+					"you have not installed. LaTeX output may not be possible.\n"
+					"Missing prerequisites:\n"
+						"\t%2$s\n"
+					"See section 3.1.2.3 (Modules) of the User's Guide for more information."),
+				from_utf8(ceName), prereqs);
+			frontend::Alert::warning(_("Package not available"), msg, true);
+		}
+		FileName layout_file = libFileSearch("citeengines", ce->getFilename());
+		if (!doc_class->read(layout_file, TextClass::CITE_ENGINE)) {
+			docstring const msg =
+						bformat(_("Error reading cite engine %1$s\n"), from_utf8(ceName));
+			frontend::Alert::warning(_("Read Error"), msg);
+		}
+	}
+
 	return doc_class;
 }
 

src/TextClass.h

@@ -151,6 +151,7 @@ public:
 		BASECLASS, //>This is a base class, i.e., top-level layout file
 		MERGE, //>This is a file included in a layout file
 		MODULE, //>This is a layout module
+		CITE_ENGINE, //>This is a cite engine
 		VALIDATION //>We're just validating
 	};
 	/// return values for read()
@@ -498,6 +499,7 @@ private:
 	/// The only way to make a DocumentClass is to call this function.
 	friend DocumentClassPtr
 		getDocumentClass(LayoutFile const &, LayoutModuleList const &,
+				 LayoutModuleList const &,
 				 bool const clone);
 };
 
@@ -508,6 +510,7 @@ private:
 /// on the CutStack.
 DocumentClassPtr getDocumentClass(LayoutFile const & baseClass,
 			LayoutModuleList const & modlist,
+			LayoutModuleList const & celist,
 			bool const clone = false);
 
 /// convert page sides option to text 1 or 2

src/tex2lyx/Makefile.am

@@ -83,6 +83,7 @@ updatetests: tex2lyx
 
 LINKED_FILES = \
 	../Author.cpp \
+	../CiteEnginesList.cpp \
 	../Color.cpp \
 	../Counters.cpp \
 	../Encoding.cpp \

src/tex2lyx/tex2lyx.cpp

@@ -282,10 +282,11 @@ void initModules()
 		for (; it != end; ++it) {
 			string const module = it->getID();
 			LayoutModuleList m;
+			LayoutModuleList c;
 			vector<string> v;
 			if (!addModule(module, baseClass, m, v))
 				continue;
-			modules[module] = getDocumentClass(baseClass, m);
+			modules[module] = getDocumentClass(baseClass, m, c);
 		}
 		init = false;
 	}