#include "music.h"
#include "decoder.h"
#include "encoder.h"
#include "tag.h"
#include "config.h"

#include <boost/format.hpp>
#include <boost/algorithm/string/predicate.hpp>
#include <boost/algorithm/string/classification.hpp>
#include <boost/algorithm/string/split.hpp>
#include <boost/algorithm/string/join.hpp>
#include <boost/cast.hpp>
#include <boost/filesystem/fstream.hpp>
#include <boost/foreach.hpp>
#include <soci/soci.h>

fs::path music::root_directory;

void music::init(std::string root) {
	// remove trailing slash
	if(boost::algorithm::ends_with(root, "/"))
		root = root.substr(0, root.size()-1);
	root_directory = root;
}

/** 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.
 */
MusicListing::p music::get(const HTTP::Connection::PathList& path) {
	// prefix path with our root_directory
	fs::path p = root_directory;
	
	for(HTTP::Connection::PathList::const_iterator it = path.begin(); it != path.end(); it++) {
		// don't allow requests with /../ in the path
		if(*it == "..") {
			return MusicListing::p();
		}
		
		p /= *it;
	}
	
	if(fs::is_directory(p)) {
		boost::shared_ptr<MusicListing> ml(new MusicDirectory(p));
		return ml;
	} else if(fs::is_regular_file(p)) {
		boost::shared_ptr<MusicListing> ml(new MusicTrack(p));
		return ml;
	}

	return MusicListing::p();
}

/** 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) {
	HTTP::Connection::PathList path_vector;
	boost::algorithm::split(path_vector, path, boost::algorithm::is_any_of("/\\"));
	return get(path_vector);
}

/** Fetches a directory.
 *  This is a helper function which returns a null pointer if the fetched MusicListing isn't a directory.
 */
MusicDirectory::p music::get_directory(const std::string& path) {
	MusicListing::p ml = get(path);
	if(!ml || !fs::is_directory(ml->path)) {
		return MusicDirectory::p();
	}
	MusicDirectory::p dir(boost::dynamic_pointer_cast<MusicDirectory>(ml));

	return dir;
}

/** 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();
	st.execute(true);

	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>());

	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++) {
		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;
	if(dir) {
		update(dir->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) {
		std::cout << "track " << t << std::endl;
		Tag::p tag = Tag::load(t.string());
		BOOST_FOREACH(Tag::Fields::value_type& f, tag->fields) {
			std::cout << boost::format("  %s: %s") % f.first % f.second << std::endl;
		}

		int artist_id = 0, album_id = 0, track_id = 0;

		if(tag->has_field("artist")) {
			sql << "SELECT id FROM artists WHERE name = :name", soci::use(tag->fields["artist"]), soci::into(artist_id);
			if(!sql.got_data())
				sql << "INSERT INTO artists (name) VALUES (:name) RETURNING id", soci::use(tag->fields["artist"]), soci::into(artist_id);
		}

		if(tag->has_field("album")) {
			std::string query(boost::str(boost::format("SELECT id FROM albums WHERE %s AND name = :name") %
						(artist_id ? boost::str(boost::format("artist_id = %d") % artist_id) : "artist_id IS NULL")));
			sql << query, soci::use(tag->fields["album"]), soci::into(album_id);
			if(!sql.got_data()) {
				soci::indicator ind = (artist_id ? soci::i_ok : soci::i_null);
				sql << "INSERT INTO albums (artist_id, name) VALUES (:artist_id, :name) RETURNING id",
					soci::use(artist_id, ind), soci::use(tag->fields["album"]), soci::into(album_id);
			}
		}

		if(tag->has_field("title")) {
			std::string query(boost::str(boost::format("SELECT id FROM tracks WHERE %s AND %s AND name = :name") %
						(artist_id ? boost::str(boost::format("artist_id = %d") % artist_id) : "artist_id IS NULL") %
						(album_id ? boost::str(boost::format("album_id = %d") % album_id) : "album_id IS NULL")));
			sql << query, soci::use(tag->fields["title"]), soci::into(track_id);
			if(!sql.got_data()) {
				soci::indicator artist_ind = (artist_id ? soci::i_ok : soci::i_null),
					album_ind = (album_id ? soci::i_ok : soci::i_null);
				sql << "INSERT INTO tracks (artist_id, album_id, name, file_name) VALUES (:artist_id, :album_id, :name, :file_name)",
					soci::use(artist_id, artist_ind), soci::use(album_id, album_ind), soci::use(tag->fields["title"]), soci::use(t.string());
			}
		}
	}
	sql.close();

	std::for_each(dir.directories.begin(), dir.directories.end(), update);
}

void MusicDirectory::render(HTTP::Connection::p req) {
	req->add_header("content-type", "text/html");

	std::string base_path = boost::algorithm::join(req->base_path, "/");

	// strip root_directory from the absolute file path
	std::string rel_base(path.string().substr(music::root_directory.string().size()));
	// set relative base to "/" if we're at the root_directory
	if(!rel_base.size())
		rel_base = "/";
	req->send_data(boost::str(boost::format("<h1>%s</h1>") % rel_base));

	// link to parent directory if we're not at the root_directory
	if(rel_base != "/") {
		std::string rel_parent(rel_base.substr(0, rel_base.find_last_of('/')));
		req->send_data(boost::str(boost::format("<a href=\"/%s%s/\">..</a><br />") % base_path % rel_parent));
	}

	for(PathListings::iterator it = directories.begin(); it != directories.end(); it++) {
		std::string rel_path = it->string().substr(music::root_directory.string().size());
		req->send_data(boost::str(boost::format("<a href=\"/%s%s/\">%s</a><br />") % base_path % rel_path % it->filename()));
	}
	for(PathListings::iterator it = tracks.begin(); it != tracks.end(); it++) {
		std::string rel_path = it->string().substr(music::root_directory.string().size());
		req->send_data(boost::str(boost::format("<a href=\"/%s%s\">%s</a><br />") % base_path % rel_path % it->filename()));
	}
}

MusicTrack::MusicTrack(const fs::path path) {
	std::cout << path << std::endl;
	this->path = path;
}

MusicDirectory::MusicDirectory(const fs::path root) {
	this->path = root;
	std::cout << this->path << std::endl;

	fs::directory_iterator end_itr;
	for(fs::directory_iterator it(this->path); it != end_itr; it++) {
		if(fs::is_directory(it->status())) {
			directories.push_back(it->path());
		} else if(fs::is_regular_file(it->status())) {
			tracks.push_back(it->path());
		}
	}
}

void MusicTrack::render(HTTP::Connection::p req) {
	req->add_header("content-type", "application/octet-stream");

	if(req->args.count("decoder") && req->args.count("encoder")) {
		Decoder::p decoder = Decoder::get(req->args["decoder"], path.string());
		Encoder::p encoder = Encoder::get(req->args["encoder"], decoder);
		
		// TODO: Make an encoder-to-istream adapter to get rid of this:
		char data[0x10000];
		std::streamsize size = 1;
		while(size) {
			size = encoder->read(data, 0x10000);
			if(size > 0)
				req->send_data(data, size);
		}
		
	} else {
		fs::ifstream is(path, std::ios::in | std::ios::binary);
		is.seekg(0, std::ios::end);
		req->add_header("content-length", boost::str(boost::format("%d") % is.tellg()));
		is.seekg(0, std::ios::beg);

		req->send_data(is);
	}
}