/*
 * This file is a part of PikoTools
 * and is distributed under the (new) BSD licence.
 * Author: Tomasz Sowa <t.sowa@ttmath.org>
 */

/* 
 * Copyright (c) 2011-2012, Tomasz Sowa
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * 
 *  * Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 *    
 *  * Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *    
 *  * Neither the name Tomasz Sowa nor the names of contributors to this
 *    project may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef headerfile_picotools_mainparser_mainparser
#define headerfile_picotools_mainparser_mainparser


namespace PT
{


/*
	a very little parser for main(int argc, char ** argv) parameters
	look in sample/sample.cpp how to use the parser
*/
class MainParser
{
public:

	MainParser();
	MainParser(int argc, const char ** argv);

	// setting arguments passed to main(int argc, char ** argv) function
	void Set(int argc, const char ** argv);

	// reseting the current state of parsing
	// now you can start parsing from the beginning
	// you don't have to call it for the first time
	// (is automatically called by the Set method)
	void Reset();

	// checking if there is a next single or double parameter
	// this method represents the main loop of checking parameters
	bool NextParam();

	// returning a single parameter (if exists) or '\0' otherwise
	// single parameter means a parameter with '-' at the beginning e.g. "-a"
	// next call to this method (without calling NextParam) returns the same value
	// this method should be called after NextParam()
	char GetSingleParam();

	// calling GetSingleParam() and comparign with 'c'
	bool IsSingleParam(char c);

	// returning a string for a double parameter or an empty string if there is no such a parameter
	// double parameter means a parameter with '--' at the beginning e.g. "--output"
	// next call to this method (without calling NextParam) returns the same value
	// GetDoubleParam() should be called after NextParam()
	// this method never returns a null pointer -- if there is no a param name (end of the string)
	// a pointer to en empty string will be returned
	const char * GetDoubleParam();

	// calling GetDoubleParam() and comparing with 'param'
	// so you don't have to call strcmp directly
	bool IsDoubleParam(const char * param);

	// returning a string representing a value
	// you have to know which parameter requires a value
	// and if such a parameter is found then use this method to obtain the value
	// the method advances the current pointer so next call to this method return a next value
	// you can call GetValue() even when NextParam() has returned false
	// in such a case this gets you the last values (those at the end of the parameter list)
	// this method never returns a null pointer -- if there is no a value (end of the string)
	// a pointer to en empty string will be returned
	const char * GetValue();

	// returning true if the input string is finished
	// there are no more parameters or values
	bool IsEnd();

	// returning true if there is a single parameter
	// should be called after NextParam()
	bool HasSingleParam();

	// returning true if there is a double parameter
	// should be called after NextParam()
	bool HasDoubleParam();

private:

	bool Advance();

	int argindex;
	int offset;
	int argsize;
	const char ** arg;
	char empty;
	bool has_single_param;
	bool has_double_param;
	char last_single_param;
	const char * last_double_param;
};


} // namespace


#endif