/* -*- C++ -*-
 * Copyright ©2005 Hugo Mills <hugo@carfax.org.uk>
 *
 * This software is distributed under the terms of the GNU GPL
 * For more information on the GPL, see the file COPYING or 
 * visit http://www.gnu.org/
 *
 * This software is distributed without warranty
 */

#include "magellan/options.h"
#include "config.h"

#include <getopt.h>
#include <cstdlib>
#include <string>
#include <cstring>
#include <fstream>
#include <sys/types.h>
#include <sys/stat.h>

Options* opts;

const int NO_PLUGIN_PATH = 256;
const int NO_DATA_PATH = 257;

struct option LONG_OPTS[] = {
	{ "help", no_argument, NULL, 'h' },
	{ "version", no_argument, NULL, 'v' },
	{ "config", required_argument, NULL, 'c' },
	{ "plugin-path", required_argument, NULL, 'P' },
	{ "no-plugin-path", no_argument, NULL, NO_PLUGIN_PATH },
	{ "include", required_argument, NULL, 'I' },
	{ "no-include-path", no_argument, NULL, NO_DATA_PATH },
	{ "debug", required_argument, NULL, 'D' }
};

const char* SHORT_OPTS = "hvc:P:I:D::";

Options::Options(int argc, char* argv[])
	: _debug_plugin(0),
	  _debug_parse(0),
	  _debug_render(0),
	  _debug_lexer(0)
{
	int index;
	int opt;
	int i;
	std::string path;

	std::string cfilename = "";
	std::string homedir_str = "";
	char* homedir = getenv("HOME");
	if(homedir != NULL)
	{
		homedir_str = homedir;
		if(homedir_str[homedir_str.length()-1] != '/')
			homedir_str += "/";
	}
	cfilename = homedir_str + ".magellanrc";

	add_plugin_path("/usr/lib/magellan/plugins/");
	add_plugin_path("/usr/local/lib/magellan/plugins/");
	add_plugin_path(homedir_str + "lib/magellan/plugins/");
	add_plugin_path("./plugins/");

	add_data_path("/usr/lib/magellan/");
	add_data_path("/usr/local/lib/magellan/");
	add_data_path(homedir_str + "lib/magellan/");

	while((opt = getopt_long(argc, argv, SHORT_OPTS, LONG_OPTS, &index))
		  != -1)
	{
		switch(opt)
		{
		case 'h':
			help();
			exit(0);
			break;
		case 'v':
			std::cout << "Magellan v" PACKAGE_VERSION " ©2008 HRMills";
			std::cout << std::endl;
			exit(0);
			break;
		case 'c':
			cfilename = optarg;
			break;
		case 'D':
			if(optarg)
			{
				i = 0;
				char c;
				while((c = optarg[i++]) != 0)
				{
					switch(c)
					{
					case 'p': _debug_plugin++; break;
					case 'c': _debug_parse++; break;
					case 'r': _debug_render++; break;
					case 'l': _debug_lexer++; break;
					default:
						std::cerr << "Debug option " << c 
								  << " not known" << std::endl;
						help();
						exit(2);
						break;
					}
				}
			}
			else
			{
				_debug_plugin 
					= _debug_parse
					= 1;
			}
			break;
		case NO_PLUGIN_PATH:
			clear_plugin_path();
			break;
		case 'P':
			path = optarg;
			if(optarg[strlen(optarg)-1] != '/')
				path += "/";
			add_plugin_path(path);
			break;
		case NO_DATA_PATH:
			clear_data_path();
			break;
		case 'I':
			path = optarg;
			if(optarg[strlen(optarg)-1] != '/')
				path += "/";
			add_data_path(path);
			break;
		}
	}

	if(cfilename == "-")
	{
		if(debug_parse() >= 1)
			std::cerr << "Opening config from standard input" << std::endl;
		_configfile = &std::cin;
	}
	else
	{
		if(debug_parse() >= 1)
			std::cerr << "Opening config file " << cfilename << std::endl;
		_configfile = new std::ifstream(cfilename.c_str());
		if(!_configfile->good())
		{
			std::cerr << "Unable to open config file " << cfilename
					  << std::endl;
			exit(1);
		}
	}
}

Options::~Options()
{
	if(_configfile != NULL)
		delete _configfile;
}

void Options::help(void) const
{
	std::cerr << "Usage: magellan [options]\n"
			  << "Options:\n"
			  << "\t-h, --help\t\tShow this text\n"
			  << "\t-c, --config=<file>\tUse specified configuration file\n"
			  << "\t-P, --plugin-path=<dir>\tAdd <dir> to search path for plugins\n"
			  << "\t    --no-plugin-path\tStart with empty plugin path\n"
			  << "\t-I, --include=<dir>\tAdd <dir> to search path for data\n"
			  << "\t    --no-include-path\tStart with empty include path\n"
			  << "\t-D, --debug[=key]\tPrint debug info. key is one or more of:\n"
			  << "\t\t\t\t\tp\tPlugin loader\n"
			  << "\t\t\t\t\tc\tConfiguration parser\n"
			  << "\t\t\t\t\tr\tRender engine\n"
			  << "\t\t\t\t\tl\tLexer\n"
			  << std::flush;
}

bool fileexists(const std::string& name)
{
	struct stat buf;
	return stat(name.c_str(), &buf) == 0;
}

std::string Options::find_data_file(
	const std::string& sub_path,
	const std::string& filename
	) const
{
	if(debug_parse() >= 3)
		std::cerr << "Looking for data file: " << sub_path << " " 
				  << filename << std::endl;
	if(filename[0] == '/')
	{
		// It's an absolute path, so don't search
		if(fileexists(filename))
			return filename;
		if(debug_parse() >= 3)
			std::cerr << "Absolute path not found" << std::endl;
	}
	else
	{
		std::string spath = sub_path;
		if(spath[spath.length()-1] != '/')
			spath += "/";

		for(std::list<std::string>::const_iterator it1 = data_search_path.begin();
			it1 != data_search_path.end();
			it1++)
		{
			std::string fullname = *it1 + spath + filename;

			if(debug_parse() >= 3)
				std::cerr << "Looking in " << fullname << std::endl;
				
			if(fileexists(fullname))
				return fullname;
		}
	}

	return "";
}