/******************************************************************************
 *
 *  file:  ValueArg.h
 *
 *  Copyright (c) 2003, Michael E. Smoot .
 *  Copyright (c) 2004, Michael E. Smoot, Daniel Aarno.
 *  All rights reverved.
 *
 *  See the file COPYING in the top directory of this distribution for
 *  more information.
 *
 *  THE SOFTWARE IS PROVIDED _AS IS_, WITHOUT WARRANTY OF ANY KIND, EXPRESS
 *  OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 *  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 *  THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 *  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 *  FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 *  DEALINGS IN THE SOFTWARE.
 *
 *****************************************************************************/


#ifndef TCLAP_VALUE_ARGUMENT_H
#define TCLAP_VALUE_ARGUMENT_H

#include <string>
#include <vector>

#include <tclap/Arg.h>
#include <tclap/Constraint.h>

namespace TCLAP
{
	/**
	 * The basic labeled argument that parses a value.
	 * This is a template class, which means the type T defines the type
	 * that a given object will attempt to parse when the flag/name is matched
	 * on the command line.  While there is nothing stopping you from creating
	 * an unflagged ValueArg, it is unwise and would cause significant problems.
	 * Instead use an UnlabeledValueArg.
	 */
	template<class T>
	class ValueArg : public Arg
	{
		protected:
			/**
			   * The value parsed from the command line.
			   * Can be of any type, as long as the >> operator for the type
			   * is defined.
			   */
			T _value;

			/**
			 * Used to support the reset() method so that ValueArg can be
			 * reset to their constructed value.
			 */
			T _default;

			/**
			   * A human readable description of the type to be parsed.
			   * This is a hack, plain and simple.  Ideally we would use RTTI to
			   * return the name of type T, but until there is some sort of
			   * consistent support for human readable names, we are left to our
			   * own devices.
			   */
			std::string _typeDesc;

			/**
			   * A Constraint this Arg must conform to.
			   */
			Constraint<T> *_constraint;

			/**
			   * Extracts the value from the string.
			   * Attempts to parse string as type T, if this fails an exception
			   * is thrown.
			   * \param val - value to be parsed.
			   */
			void _extractValue(const std::string &val);

		public:
			/**
			   * Labeled ValueArg constructor.
			   * You could conceivably call this constructor with a blank flag,
			   * but that would make you a bad person.  It would also cause
			   * an exception to be thrown.   If you want an unlabeled argument,
			   * use the other constructor.
			   * \param flag - The one character flag that identifies this
			   * argument on the command line.
			   * \param name - A one word name for the argument.  Can be
			   * used as a long flag on the command line.
			   * \param desc - A description of what the argument is for or
			   * does.
			   * \param req - Whether the argument is required on the command
			   * line.
			   * \param value - The default value assigned to this argument if it
			   * is not present on the command line.
			   * \param typeDesc - A short, human readable description of the
			   * type that this object expects.  This is used in the generation
			   * of the USAGE statement.  The goal is to be helpful to the end user
			   * of the program.
			   * \param v - An optional visitor.  You probably should not
			   * use this unless you have a very good reason.
			   */
			ValueArg(const std::string &flag, const std::string &name, const std::string &desc, bool req,
			        T value, const std::string &typeDesc, Visitor *v = NULL);


			/**
			   * Labeled ValueArg constructor.
			   * You could conceivably call this constructor with a blank flag,
			   * but that would make you a bad person.  It would also cause
			   * an exception to be thrown.   If you want an unlabeled argument,
			   * use the other constructor.
			   * \param flag - The one character flag that identifies this
			   * argument on the command line.
			   * \param name - A one word name for the argument.  Can be
			   * used as a long flag on the command line.
			   * \param desc - A description of what the argument is for or
			   * does.
			   * \param req - Whether the argument is required on the command
			   * line.
			   * \param value - The default value assigned to this argument if it
			   * is not present on the command line.
			   * \param typeDesc - A short, human readable description of the
			   * type that this object expects.  This is used in the generation
			   * of the USAGE statement.  The goal is to be helpful to the end user
			   * of the program.
			   * \param parser - A CmdLine parser object to add this Arg to
			   * \param v - An optional visitor.  You probably should not
			   * use this unless you have a very good reason.
			   */
			ValueArg(const std::string &flag, const std::string &name, const std::string &desc, bool req,
			        T value, const std::string &typeDesc, CmdLineInterface &parser, Visitor *v = NULL);

			/**
			   * Labeled ValueArg constructor.
			   * You could conceivably call this constructor with a blank flag,
			   * but that would make you a bad person.  It would also cause
			   * an exception to be thrown.   If you want an unlabeled argument,
			   * use the other constructor.
			   * \param flag - The one character flag that identifies this
			   * argument on the command line.
			   * \param name - A one word name for the argument.  Can be
			   * used as a long flag on the command line.
			   * \param desc - A description of what the argument is for or
			   * does.
			   * \param req - Whether the argument is required on the command
			   * line.
			   * \param value - The default value assigned to this argument if it
			   * is not present on the command line.
			   * \param constraint - A pointer to a Constraint object used
			* to constrain this Arg.
			   * \param parser - A CmdLine parser object to add this Arg to.
			   * \param v - An optional visitor.  You probably should not
			   * use this unless you have a very good reason.
			   */
			ValueArg(const std::string &flag, const std::string &name, const std::string &desc, bool req,
			        T value, Constraint<T> *constraint, CmdLineInterface &parser, Visitor *v = NULL);

			/**
			   * Labeled ValueArg constructor.
			   * You could conceivably call this constructor with a blank flag,
			   * but that would make you a bad person.  It would also cause
			   * an exception to be thrown.   If you want an unlabeled argument,
			   * use the other constructor.
			   * \param flag - The one character flag that identifies this
			   * argument on the command line.
			   * \param name - A one word name for the argument.  Can be
			   * used as a long flag on the command line.
			   * \param desc - A description of what the argument is for or
			   * does.
			   * \param req - Whether the argument is required on the command
			   * line.
			   * \param value - The default value assigned to this argument if it
			   * is not present on the command line.
			   * \param constraint - A pointer to a Constraint object used
			* to constrain this Arg.
			   * \param v - An optional visitor.  You probably should not
			   * use this unless you have a very good reason.
			   */
			ValueArg(const std::string &flag, const std::string &name, const std::string &desc, bool req,
			        T value, Constraint<T> *constraint, Visitor *v = NULL);

			/**
			   * Handles the processing of the argument.
			   * This re-implements the Arg version of this method to set the
			   * _value of the argument appropriately.  It knows the difference
			   * between labeled and unlabeled.
			   * \param i - Pointer the the current argument in the list.
			   * \param args - Mutable list of strings. Passed
			   * in from main().
			   */
			virtual bool processArg(int *i, std::vector<std::string> &args);

			/**
			   * Returns the value of the argument.
			   */
			T& getValue();

			/**
			   * Specialization of shortID.
			   * \param val - value to be used.
			   */
			virtual std::string shortID(const std::string &val = "val") const;

			/**
			   * Specialization of longID.
			   * \param val - value to be used.
			   */
			virtual std::string longID(const std::string &val = "val") const;

			virtual void reset();
	};


	/**
	 * Constructor implementation.
	 */
	template<class T>
	ValueArg<T>::ValueArg(const std::string &flag, const std::string &name, const std::string &desc,
	        bool req, T val, const std::string &typeDesc, Visitor *v) :
			Arg(flag, name, desc, req, true, v), _value(val), _default(val), _typeDesc(typeDesc),
			_constraint(NULL)
	{
	}

	template<class T>
	ValueArg<T>::ValueArg(const std::string &flag, const std::string &name, const std::string &desc,
	        bool req, T val, const std::string &typeDesc, CmdLineInterface &parser,
	        Visitor *v) :
			Arg(flag, name, desc, req, true, v), _value(val), _default(val), _typeDesc(typeDesc),
			_constraint(NULL)
	{
		parser.add(this);
	}

	template<class T>
	ValueArg<T>::ValueArg(const std::string &flag, const std::string &name, const std::string &desc,
	        bool req, T val, Constraint<T> *constraint, Visitor *v) :
			Arg(flag, name, desc, req, true, v), _value(val), _default(val), _typeDesc(
				constraint->shortID()), _constraint(constraint)
	{
	}

	template<class T>
	ValueArg<T>::ValueArg(const std::string &flag, const std::string &name, const std::string &desc,
	        bool req, T val, Constraint<T> *constraint, CmdLineInterface &parser,
	        Visitor *v) :
			Arg(flag, name, desc, req, true, v), _value(val), _default(val), _typeDesc(
				constraint->shortID()), _constraint(constraint)
	{
		parser.add(this);
	}

	/**
	 * Implementation of getValue().
	 */
	template<class T>
	T& ValueArg<T>::getValue()
	{
		return _value;
	}

	/**
	 * Implementation of processArg().
	 */
	template<class T>
	bool ValueArg<T>::processArg(int *i, std::vector<std::string> &args)
	{
		if (_ignoreable && Arg::ignoreRest())
		{
			return false;
		}

		if (_hasBlanks(args[*i]))
		{
			return false;
		}

		std::string flag = args[*i];

		std::string value = "";
		trimFlag(flag, value);

		if (argMatches(flag))
		{
			if (_alreadySet)
			{
				throw (CmdLineParseException("Argument already set!", toString()));
			}

			if (Arg::delimiter() != ' ' && value == "")
			{
				throw (ArgParseException(
								"Couldn't find delimiter for this argument!", toString()));
			}

			if (value == "")
			{
				(*i)++;
				if (static_cast<unsigned int>(*i) < args.size())
				{
					_extractValue(args[*i]);
				}
				else
				{
					throw (ArgParseException("Missing a value for this argument!", toString()));
				}
			}
			else
			{
				_extractValue(value);
			}

			_alreadySet = true;
			_checkWithVisitor();
			return true;
		}
		else
		{
			return false;
		}
	}

	/**
	 * Implementation of shortID.
	 */
	template<class T>
	std::string ValueArg<T>::shortID(const std::string &val) const
	{
		static_cast<void>(val); // Ignore input, don't warn
		return Arg::shortID(_typeDesc);
	}

	/**
	 * Implementation of longID.
	 */
	template<class T>
	std::string ValueArg<T>::longID(const std::string &val) const
	{
		static_cast<void>(val); // Ignore input, don't warn
		return Arg::longID(_typeDesc);
	}

	template<class T>
	void ValueArg<T>::_extractValue(const std::string &val)
	{
		try
		{
			ExtractValue(_value, val, typename ArgTraits<T>::ValueCategory());
		}
		catch (ArgParseException &e)
		{
			throw ArgParseException(e.error(), toString());
		}

		if (_constraint != NULL)
		{
			if (!_constraint->check(_value))
			{
				throw (CmdLineParseException("Value '" + val + +"' does not meet constraint: " +
				      _constraint->description(), toString()));
			}
		}
	}

	template<class T>
	void ValueArg<T>::reset()
	{
		Arg::reset();
		_value = _default;
	}
}

#endif