/* 
    Copyright (C) 2006 Paul Davis

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

    $Id$
*/

#include <pbd/enumwriter.h>
#include <pbd/error.h>
#include <pbd/compose.h>

using namespace std;
using namespace PBD;

#include "i18n.h"

EnumWriter* EnumWriter::_instance = 0;

EnumWriter::EnumWriter ()
{
	if (_instance == 0) {
		_instance = this;
	}
}

EnumWriter::~EnumWriter ()
{
}

void
EnumWriter::register_distinct (string type, vector<int> v, vector<string> s)
{
	pair<string,EnumRegistration> newpair;
	pair<Registry::iterator,bool> result;

	newpair.first = type;
	newpair.second = EnumRegistration (v, s, false);
	
	result = registry.insert (newpair);

	if (!result.second) {
		warning << string_compose (_("enum type \"%1\" already registered with the enum writer"), type) << endmsg;
	}
}

void
EnumWriter::register_bits (string type, vector<int> v, vector<string> s)
{
	pair<string,EnumRegistration> newpair;
	pair<Registry::iterator,bool> result;

	newpair.first = type;
	newpair.second = EnumRegistration (v, s, true);
	
	result = registry.insert (newpair);

	if (!result.second) {
		warning << _("enum type \"%1\" already registered with the enum writer") << endmsg;
	}
}

string
EnumWriter::write (string type, int value)
{
	Registry::iterator x = registry.find (type);

	if (x == registry.end()) {
		error << string_compose (_("EnumWriter: unknown enumeration type \"%1\""), type) << endmsg;
		throw unknown_enumeration();
	}

	if (x->second.bitwise) {
		return write_bits (x->second, value);
	} else {
		return write_distinct (x->second, value);
	}
}

int
EnumWriter::read (string type, string value)
{
	Registry::iterator x = registry.find (type);

	if (x == registry.end()) {
		error << string_compose (_("EnumWriter: unknown enumeration type \"%1\""), type) << endmsg;
		throw unknown_enumeration();
	}

	if (x->second.bitwise) {
		return read_bits (x->second, value);
	} else {
		return read_distinct (x->second, value);
	}
}	

string
EnumWriter::write_bits (EnumRegistration& er, int value)
{
	vector<int>::iterator i;
	vector<string>::iterator s;
	string result;

	for (i = er.values.begin(), s = er.names.begin(); i != er.values.end(); ++i, ++s) {
		if (value & (*i)) {
			if (!result.empty()) {
				result += ',';
			} 
			result += (*s);
		}
	}

	return result;
}

string
EnumWriter::write_distinct (EnumRegistration& er, int value)
{
	vector<int>::iterator i;
	vector<string>::iterator s;

	for (i = er.values.begin(), s = er.names.begin(); i != er.values.end(); ++i, ++s) {
		if (value == (*i)) {
			return (*s);
		}
	}

	return string();
}

int
EnumWriter::read_bits (EnumRegistration& er, string str)
{
	vector<int>::iterator i;
	vector<string>::iterator s;
	int result = 0;
	bool found = false;
	string::size_type comma;

	do {
		
		comma = str.find_first_of (',');
		string segment = str.substr (0, comma);

		for (i = er.values.begin(), s = er.names.begin(); i != er.values.end(); ++i, ++s) {
			if (segment == (*s)) {
				result |= (*i);
				found = true;
			}
		}

		if (comma == string::npos) {
			break;
		}

		str = str.substr (comma+1);

	} while (true);

	if (!found) {
		throw unknown_enumeration();
	}

	return result;
}

int
EnumWriter::read_distinct (EnumRegistration& er, string str)
{
	vector<int>::iterator i;
	vector<string>::iterator s;

	for (i = er.values.begin(), s = er.names.begin(); i != er.values.end(); ++i, ++s) {
		if (str == (*s)) {
			return (*i);
		}
	}

	throw unknown_enumeration();
}