/**
 * \file InsetCitation.cpp
 * This file is part of LyX, the document processor.
 * Licence details can be found in the file COPYING.
 *
 * \author Angus Leeming
 * \author Herbert Voß
 *
 * Full author contact details are available in file CREDITS.
 */

#include <config.h>

#include "InsetCitation.h"

#include "Buffer.h"
#include "BufferParams.h"
#include "DispatchResult.h"
#include "support/gettext.h"
#include "EmbeddedFiles.h"
#include "FuncRequest.h"
#include "LaTeXFeatures.h"

#include "support/debug.h"
#include "support/docstream.h"
#include "support/lstrings.h"

#include <algorithm>

using namespace std;
using namespace lyx::support;

namespace lyx {

namespace {

vector<string> const init_possible_cite_commands()
{
	char const * const possible[] = {
		"cite", "nocite", "citet", "citep", "citealt", "citealp",
		"citeauthor", "citeyear", "citeyearpar",
		"citet*", "citep*", "citealt*", "citealp*", "citeauthor*",
		"Citet",  "Citep",  "Citealt",  "Citealp",  "Citeauthor",
		"Citet*", "Citep*", "Citealt*", "Citealp*", "Citeauthor*",
		"fullcite",
		"footcite", "footcitet", "footcitep", "footcitealt",
		"footcitealp", "footciteauthor", "footciteyear", "footciteyearpar",
		"citefield", "citetitle", "cite*"
	};
	size_t const size_possible = sizeof(possible) / sizeof(possible[0]);

	return vector<string>(possible, possible + size_possible);
}


vector<string> const & possible_cite_commands()
{
	static vector<string> const possible = init_possible_cite_commands();
	return possible;
}


//FIXME See the header for the issue.
string const default_cite_command(biblio::CiteEngine engine)
{
	string str;
	switch (engine) {
		case biblio::ENGINE_BASIC:
			str = "cite";
			break;
		case biblio::ENGINE_NATBIB_AUTHORYEAR:
			str = "citet";
			break;
		case biblio::ENGINE_NATBIB_NUMERICAL:
			str = "citep";
			break;
		case biblio::ENGINE_JURABIB:
			str = "cite";
			break;
	}
	return str;
}

		
string const 
		asValidLatexCommand(string const & input, biblio::CiteEngine const engine)
{
	string const default_str = default_cite_command(engine);
	if (!InsetCitation::isCompatibleCommand(input))
		return default_str;

	string output;
	switch (engine) {
		case biblio::ENGINE_BASIC:
			output = input;
			break;

		case biblio::ENGINE_NATBIB_AUTHORYEAR:
		case biblio::ENGINE_NATBIB_NUMERICAL:
			if (input == "cite" || input == "citefield" ||
							input == "citetitle" || input == "cite*")
				output = default_str;
			else if (prefixIs(input, "foot"))
				output = input.substr(4);
			else
				output = input;
			break;

		case biblio::ENGINE_JURABIB: {
			// Jurabib does not support the 'uppercase' natbib style.
			if (input[0] == 'C')
				output = string(1, 'c') + input.substr(1);
			else
				output = input;

			// Jurabib does not support the 'full' natbib style.
			string::size_type const n = output.size() - 1;
			if (output != "cite*" && output[n] == '*')
				output = output.substr(0, n);

			break;
		}
	}

	return output;
}


docstring const getComplexLabel(Buffer const & buffer,
			    string const & citeType, docstring const & keyList,
			    docstring const & before, docstring const & after,
			    biblio::CiteEngine engine)
{
	// Only start the process off after the buffer is loaded from file.
	if (!buffer.isFullyLoaded())
		return docstring();

	// Cache the labels
	typedef map<Buffer const *, BiblioInfo> CachedMap;
	static CachedMap cached_keys;

	// and cache the timestamp of the bibliography files.
	static map<FileName, time_t> bibfileStatus;

	BiblioInfo biblist;

	EmbeddedFileList const & bibfilesCache = buffer.getBibfilesCache();
	// compare the cached timestamps with the actual ones.
	bool changed = false;
	for (EmbeddedFileList::const_iterator it = bibfilesCache.begin();
			it != bibfilesCache.end(); ++ it) {
		FileName const f = *it;
		time_t lastw = f.lastModified();
		if (lastw != bibfileStatus[f]) {
			changed = true;
			bibfileStatus[f] = lastw;
		}
	}

	// build the list only if the bibfiles have been changed
	if (cached_keys[&buffer].empty() || bibfileStatus.empty() || changed) {
		biblist.fillWithBibKeys(&buffer);
		cached_keys[&buffer] = biblist;
	} else {
		// use the cached keys
		biblist = cached_keys[&buffer];
	}

	if (biblist.empty())
		return docstring();

	// the natbib citation-styles
	// CITET:	author (year)
	// CITEP:	(author,year)
	// CITEALT:	author year
	// CITEALP:	author, year
	// CITEAUTHOR:	author
	// CITEYEAR:	year
	// CITEYEARPAR:	(year)
	// jurabib supports these plus
	// CITE:	author/<before field>

	// We don't currently use the full or forceUCase fields.
	string cite_type = asValidLatexCommand(citeType, engine);
	if (cite_type[0] == 'C')
		//If we were going to use them, this would mean ForceUCase
		cite_type = string(1, 'c') + cite_type.substr(1);
	if (cite_type[cite_type.size() - 1] == '*')
		//and this would mean FULL
		cite_type = cite_type.substr(0, cite_type.size() - 1);

	docstring before_str;
	if (!before.empty()) {
		// In CITET and CITEALT mode, the "before" string is
		// attached to the label associated with each and every key.
		// In CITEP, CITEALP and CITEYEARPAR mode, it is attached
		// to the front of the whole only.
		// In other modes, it is not used at all.
		if (cite_type == "citet" ||
		    cite_type == "citealt" ||
		    cite_type == "citep" ||
		    cite_type == "citealp" ||
		    cite_type == "citeyearpar")
			before_str = before + ' ';
		// In CITE (jurabib), the "before" string is used to attach
		// the annotator (of legal texts) to the author(s) of the
		// first reference.
		else if (cite_type == "cite")
			before_str = '/' + before;
	}

	docstring after_str;
	// The "after" key is appended only to the end of the whole.
	if (cite_type == "nocite")
		after_str =  " (" + _("not cited") + ')';
	else if (!after.empty()) {
		after_str = ", " + after;
	}

	// One day, these might be tunable (as they are in BibTeX).
	char op, cp;	// opening and closing parenthesis.
	char * sep;	// punctuation mark separating citation entries.
	if (engine == biblio::ENGINE_BASIC) {
		op  = '[';
		cp  = ']';
		sep = ",";
	} else {
		op  = '(';
		cp  = ')';
		sep = ";";
	}

	docstring const op_str = ' ' + docstring(1, op);
	docstring const cp_str = docstring(1, cp) + ' ';
	docstring const sep_str = from_ascii(sep) + ' ';

	docstring label;
	vector<docstring> keys = getVectorFromString(keyList);
	vector<docstring>::const_iterator it  = keys.begin();
	vector<docstring>::const_iterator end = keys.end();
	for (; it != end; ++it) {
		// get the bibdata corresponding to the key
		docstring const author(biblist.getAbbreviatedAuthor(*it));
		docstring const year(biblist.getYear(*it));

		// Something isn't right. Fail safely.
		if (author.empty() || year.empty())
			return docstring();

		// authors1/<before>;  ... ;
		//  authors_last, <after>
		if (cite_type == "cite") {
			if (engine == biblio::ENGINE_BASIC) {
				label += *it + sep_str;
			} else if (engine == biblio::ENGINE_JURABIB) {
				if (it == keys.begin())
					label += author + before_str + sep_str;
				else
					label += author + sep_str;
			}

		// nocite
		} else if (cite_type == "nocite") {
			label += *it + sep_str;

		// (authors1 (<before> year);  ... ;
		//  authors_last (<before> year, <after>)
		} else if (cite_type == "citet") {
			switch (engine) {
			case biblio::ENGINE_NATBIB_AUTHORYEAR:
				label += author + op_str + before_str +
					year + cp + sep_str;
				break;
			case biblio::ENGINE_NATBIB_NUMERICAL:
				label += author + op_str + before_str + '#' + *it + cp + sep_str;
				break;
			case biblio::ENGINE_JURABIB:
				label += before_str + author + op_str +
					year + cp + sep_str;
				break;
			case biblio::ENGINE_BASIC:
				break;
			}

		// author, year; author, year; ...
		} else if (cite_type == "citep" ||
			   cite_type == "citealp") {
			if (engine == biblio::ENGINE_NATBIB_NUMERICAL) {
				label += *it + sep_str;
			} else {
				label += author + ", " + year + sep_str;
			}

		// (authors1 <before> year;
		//  authors_last <before> year, <after>)
		} else if (cite_type == "citealt") {
			switch (engine) {
			case biblio::ENGINE_NATBIB_AUTHORYEAR:
				label += author + ' ' + before_str +
					year + sep_str;
				break;
			case biblio::ENGINE_NATBIB_NUMERICAL:
				label += author + ' ' + before_str + '#' + *it + sep_str;
				break;
			case biblio::ENGINE_JURABIB:
				label += before_str + author + ' ' +
					year + sep_str;
				break;
			case biblio::ENGINE_BASIC:
				break;
			}

		// author; author; ...
		} else if (cite_type == "citeauthor") {
			label += author + sep_str;

		// year; year; ...
		} else if (cite_type == "citeyear" ||
			   cite_type == "citeyearpar") {
			label += year + sep_str;
		}
	}
	label = rtrim(rtrim(label), sep);

	if (!after_str.empty()) {
		if (cite_type == "citet") {
			// insert "after" before last ')'
			label.insert(label.size() - 1, after_str);
		} else {
			bool const add =
				!(engine == biblio::ENGINE_NATBIB_NUMERICAL &&
				  (cite_type == "citeauthor" ||
				   cite_type == "citeyear"));
			if (add)
				label += after_str;
		}
	}

	if (!before_str.empty() && (cite_type == "citep" ||
				    cite_type == "citealp" ||
				    cite_type == "citeyearpar")) {
		label = before_str + label;
	}

	if (cite_type == "citep" || cite_type == "citeyearpar" || 
	    (cite_type == "cite" && engine == biblio::ENGINE_BASIC) )
		label = op + label + cp;

	return label;
}


docstring const getBasicLabel(docstring const & keyList, docstring const & after)
{
	docstring keys = keyList;
	docstring label;

	if (contains(keys, ',')) {
		// Final comma allows while loop to cover all keys
		keys = ltrim(split(keys, label, ',')) + ',';
		while (contains(keys, ',')) {
			docstring key;
			keys = ltrim(split(keys, key, ','));
			label += ", " + key;
		}
	} else
		label = keys;

	if (!after.empty())
		label += ", " + after;

	return '[' + label + ']';
}

} // anon namespace


ParamInfo InsetCitation::param_info_;


InsetCitation::InsetCitation(InsetCommandParams const & p)
	: InsetCommand(p, "citation")
{}


ParamInfo const & InsetCitation::findInfo(string const & /* cmdName */)
{
	// standard cite does only take one argument if jurabib is
	// not used, but jurabib extends this to two arguments, so
	// we have to allow both here. InsetCitation takes care that
	// LaTeX output is nevertheless correct.
	if (param_info_.empty()) {
		param_info_.add("after", true);
		param_info_.add("before", true);
		param_info_.add("key", false);
	}
	return param_info_;
}


bool InsetCitation::isCompatibleCommand(string const & cmd)
{
	vector<string> const & possibles = possible_cite_commands();
	vector<string>::const_iterator const end = possibles.end();
	return find(possibles.begin(), end, cmd) != end;
}


docstring const InsetCitation::generateLabel(Buffer const & buffer) const
{
	docstring const before = getParam("before");
	docstring const after  = getParam("after");

	docstring label;
	biblio::CiteEngine const engine = buffer.params().getEngine();
	label = getComplexLabel(buffer, getCmdName(), getParam("key"),
			       before, after, engine);

	// Fallback to fail-safe
	if (label.empty())
		label = getBasicLabel(getParam("key"), after);

	return label;
}


docstring const InsetCitation::getScreenLabel(Buffer const & buffer) const
{
	biblio::CiteEngine const engine = buffer.params().getEngine();
	if (cache.params == params() && cache.engine == engine)
		return cache.screen_label;

	// The label has changed, so we have to re-create it.
	docstring const glabel = generateLabel(buffer);

	unsigned int const maxLabelChars = 45;

	docstring label = glabel;
	if (label.size() > maxLabelChars) {
		label.erase(maxLabelChars-3);
		label += "...";
	}

	cache.engine  = engine;
	cache.params = params();
	cache.generated_label = glabel;
	cache.screen_label = label;

	return label;
}


int InsetCitation::plaintext(Buffer const & buffer, odocstream & os,
			     OutputParams const &) const
{
	docstring str;

	if (cache.params == params() &&
	    cache.engine == buffer.params().getEngine())
		str = cache.generated_label;
	else
		str = generateLabel(buffer);

	os << str;
	return str.size();
}


static docstring const cleanupWhitespace(docstring const & citelist)
{
	docstring::const_iterator it  = citelist.begin();
	docstring::const_iterator end = citelist.end();
	// Paranoia check: make sure that there is no whitespace in here
	// -- at least not behind commas or at the beginning
	docstring result;
	char_type last = ',';
	for (; it != end; ++it) {
		if (*it != ' ')
			last = *it;
		if (*it != ' ' || last != ',')
			result += *it;
	}
	return result;
}


int InsetCitation::docbook(Buffer const &, odocstream & os,
			   OutputParams const &) const
{
	os << from_ascii("<citation>")
	   << cleanupWhitespace(getParam("key"))
	   << from_ascii("</citation>");
	return 0;
}


void InsetCitation::textString(Buffer const & buf, odocstream & os) const
{
	plaintext(buf, os, OutputParams(0));
}


// Have to overwrite the default InsetCommand method in order to check that
// the \cite command is valid. Eg, the user has natbib enabled, inputs some
// citations and then changes his mind, turning natbib support off. The output
// should revert to \cite[]{}
int InsetCitation::latex(Buffer const & buffer, odocstream & os,
			 OutputParams const &) const
{
	biblio::CiteEngine cite_engine = buffer.params().getEngine();
	// FIXME UNICODE
	docstring const cite_str = from_utf8(
		asValidLatexCommand(getCmdName(), cite_engine));

	os << "\\" << cite_str;

	docstring const & before = getParam("before");
	docstring const & after  = getParam("after");
	if (!before.empty() && cite_engine != biblio::ENGINE_BASIC)
		os << '[' << before << "][" << after << ']';
	else if (!after.empty())
		os << '[' << after << ']';

	os << '{' << cleanupWhitespace(getParam("key")) << '}';

	return 0;
}


void InsetCitation::validate(LaTeXFeatures & features) const
{
	switch (features.bufferParams().getEngine()) {
	case biblio::ENGINE_BASIC:
		break;
	case biblio::ENGINE_NATBIB_AUTHORYEAR:
	case biblio::ENGINE_NATBIB_NUMERICAL:
		features.require("natbib");
		break;
	case biblio::ENGINE_JURABIB:
		features.require("jurabib");
		break;
	}
}


} // namespace lyx