Reworked "find" to allow for more sophisticated searches.

The usage of the "find" command is as follows:
	find SEARCH
where SEARCH is either a simple string to search for, or key:value pairs
with the following keys:
	artist
	album
	title

4 files changed, 97 insertions, 25 deletions

diff --git a/commands.cpp b/commands.cpp
index 84c1e5f..76ce2ff 100644
--- a/commands.cpp
+++ b/commands.cpp
@@ -3,9 +3,13 @@
 #include <boost/format.hpp>
 #include <boost/algorithm/string/join.hpp>
 #include <boost/bind.hpp>
+#include <boost/spirit/include/qi.hpp>
+#include <boost/fusion/include/std_pair.hpp>
 
 #include <iostream>
 
+namespace qi = boost::spirit::qi;
+
 std::vector<std::string> Commands::ls() {
 	if(args.size() != 2) {
 		throw CommandException("usage: ls DIR");
@@ -29,24 +33,39 @@ std::vector<std::string> Commands::ls() {
 	return result;
 }
 
+typedef std::map<std::string, std::string> stringmap;
+
+static bool find_parse(std::string str, stringmap& foo) {
+	typedef std::string::const_iterator Iterator;
+
+	Iterator begin = str.begin();
+	Iterator end = str.end();
+
+	return qi::parse(begin, end,
+		// pairs wrapped in "quotes"
+		(('"' >> +(qi::char_ - ':') >> ':' >> +(qi::char_ - '"') >> '"') |
+		// simple key:value pairs
+		(+(qi::char_ - ':' - ' ') >> ':' >> +(qi::char_ - ' ')))
+		// skip spaces between pairs
+		% +qi::char_(' '),
+		foo) && begin == end;
+}
+
 std::vector<std::string> Commands::find() {
-	if(args.size() != 3) {
-		throw CommandException("usage: find TYPE SEARCH");
+	if(args.size() < 2) {
+		throw CommandException("usage: find SEARCH");
 	}
 
-	FindFunction ff;
-	if(find_handlers.find(args[1]) != find_handlers.end()) {
-		ff = find_handlers[args[1]];
+	stringmap find_args;
+	args.erase(args.begin());
+	std::string search = boost::algorithm::join(args, " ");
+	std::vector<MusicListing::p> ml;
+	if(find_parse(search, find_args)) {
+		ml = music::find(find_args);
 	} else {
-		std::vector<std::string> types;
-		for(std::map<std::string, FindFunction>::iterator it = find_handlers.begin(); it != find_handlers.end(); it++) {
-			types.push_back(it->first);
-		}
-		std::string s = boost::str(boost::format("unknown search type, must be one of %s") % boost::algorithm::join(types, ", "));
-		throw CommandException(s.c_str());
+		ml = music::find(search);
 	}
 
-	std::vector<MusicListing::p> ml = ff(args[2]);
 	if(!ml.size()) {
 		throw CommandException("no results");
 	}
@@ -56,7 +75,6 @@ std::vector<std::string> Commands::find() {
 		result.push_back((*it)->path.string());
 	}
 
-
 	return result;
 }
 
@@ -74,7 +92,6 @@ std::vector<std::string> Commands::update() {
 Commands::Commands(boost::asio::io_service& io_service_, std::vector<std::string>& args_) : io_service(io_service_), args(args_) {
 	handlers["ls"] = &Commands::ls;
 	handlers["find"] = &Commands::find;
-	find_handlers["artist"] = music::find_artist;
 	handlers["update"] = &Commands::update;
 }
 
diff --git a/commands.h b/commands.h
index 78ecf48..3c351cf 100644
--- a/commands.h
+++ b/commands.h
@@ -24,10 +24,6 @@ class Commands {
 		typedef boost::function<std::vector<std::string> (Commands*)> Handler;
 		std::map<std::string, Handler> handlers;
 
-		typedef boost::function<std::vector<MusicListing::p> (const std::string artist)> FindFunction;
-		//! Handlers for the find command.
-		std::map<std::string, FindFunction> find_handlers;
-
 		boost::asio::io_service& io_service;
 		//! Command arguments.
 		std::vector<std::string>& args;
diff --git a/music.cpp b/music.cpp
index eb16226..7356274 100644
--- a/music.cpp
+++ b/music.cpp
@@ -24,7 +24,7 @@ void music::init(std::string root) {
 	root_directory = root;
 }
 
-/** Fetches a MusicListing object from the given path.
+/** Fetches a MusicListing object from the given \p path.
  *  Prefixes the given path with the music root directory.
  *  This can be either a track (file) or a directory.
  */
@@ -52,7 +52,7 @@ MusicListing::p music::get(const HTTP::Connection::PathList& path) {
 	return MusicListing::p();
 }
 
-/** Fetches a MusicListing object from the given path.
+/** Fetches a MusicListing object from the given \p path.
  *  Splits the given string and calls the above function.
  */
 MusicListing::p music::get(const std::string& path) {
@@ -74,21 +74,76 @@ MusicDirectory::p music::get_directory(const std::string& path) {
 	return dir;
 }
 
-std::vector<MusicListing::p> music::find_artist(const std::string artist) {
+/** Find tracks in the database.
+ *  Does a search on specific fields given by \p search.
+ */
+std::vector<MusicListing::p> music::find(std::map<std::string, std::string> search) {
+	soci::session sql(config::vm["audist.database"].as<std::string>());
+	soci::statement st(sql);
+	std::string filename, artist, album, title;
+	st.exchange(soci::into(filename));
+	std::string query = "SELECT file_name FROM tracks WHERE ";
+	std::vector<std::string> where_conditions;
+
+	if(search.find("artist") != search.end()) {
+		where_conditions.push_back("artist_id IN (SELECT id FROM artists WHERE name LIKE :artist)");
+		artist = "%"+search["artist"]+"%";
+		st.exchange(soci::use(artist, "artist"));
+	}
+
+	if(search.find("album") != search.end()) {
+		where_conditions.push_back("album_id IN (SELECT id FROM albums WHERE name LIKE :album)");
+		album = "%"+search["album"]+"%";
+		st.exchange(soci::use(album, "album"));
+	}
+
+	if(search.find("title") != search.end()) {
+		where_conditions.push_back("name LIKE :title");
+		artist = "%"+search["title"]+"%";
+		st.exchange(soci::use(title, "title"));
+	}
+
+	query += boost::algorithm::join(where_conditions, " AND ");
+	st.alloc();
+	st.prepare(query);
+	st.define_and_bind();
+	std::cout << "query: " << query << std::endl;
+	std::cout << "st.execute: " << st.execute(true) << std::endl;
+	std::cout << "st.got_data: " << st.got_data() << std::endl;
+
+	std::vector<MusicListing::p> results;
+	while(st.fetch()) {
+		MusicListing::p ml(new MusicTrack(filename));
+		results.push_back(ml);
+	}
+	sql.close();
+
+	return results;
+}
+
+/** Find tracks in the database.
+ *  Returns tracks where title, artist, album or filename matches \p search.
+ */
+std::vector<MusicListing::p> music::find(std::string search) {
 	soci::session sql(config::vm["audist.database"].as<std::string>());
 
-	soci::rowset<std::string> rs = (sql.prepare << "SELECT file_name FROM tracks WHERE artist_id IN (SELECT id FROM artists WHERE name LIKE :name)",
-		soci::use("%"+artist+"%"));
+	search = "%"+search+"%";
+	soci::rowset<std::string> rs = (sql.prepare << "SELECT DISTINCT file_name FROM tracks WHERE name LIKE :search OR file_name LIKE :search OR "
+		"artist_id IN (SELECT id FROM artists WHERE name LIKE :search) OR album_id IN (SELECT id FROM albums WHERE name LIKE :search)",
+		soci::use(search, "search"));
 
 	std::vector<MusicListing::p> results;
 	for(soci::rowset<std::string>::const_iterator it = rs.begin(); it != rs.end(); it++) {
-		boost::shared_ptr<MusicListing> ml(new MusicTrack(*it));
+		MusicListing::p ml(new MusicTrack(*it));
 		results.push_back(ml);
 	}
 
 	return results;
 }
 
+/** Initiate an update on \p path and its subdirs.
+ *  music::update does the actual work.
+ */
 void music::begin_update(const std::string path) {
 	MusicDirectory::p dir = get_directory(path);
 	std::cout << boost::format("updater(%s) called") % path << std::endl;
@@ -97,7 +152,10 @@ void music::begin_update(const std::string path) {
 	}
 }
 
+/** Recursively update \p dir and its subdirectories.
+ */
 void music::update(const MusicDirectory& dir) {
+	// TODO: Fix engine-specific SQL syntax inside this function.
 	soci::session sql(config::vm["audist.database"].as<std::string>());
 
 	BOOST_FOREACH(fs::path t, dir.tracks) {
diff --git a/music.h b/music.h
index ed47657..f7d06bd 100644
--- a/music.h
+++ b/music.h
@@ -43,7 +43,8 @@ namespace music {
 	MusicListing::p get(const HTTP::Connection::PathList& path);
 	MusicListing::p get(const std::string& path);
 	MusicDirectory::p get_directory(const std::string& path);
-	std::vector<MusicListing::p> find_artist(const std::string artist);
+	std::vector<MusicListing::p> find(const std::map<std::string, std::string> search);
+	std::vector<MusicListing::p> find(std::string search);
 	void begin_update(const std::string path);
 	void update(const MusicDirectory& dir);
 };