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#ifndef FILTER_H
#define FILTER_H

#include <vector>
#include <xercesc/dom/DOMElement.hpp>
#include "Item.h"
#include "State.h"
#include "VariableValue.h"

/**
	This class represents a filter in a set object of the oval definition schema.
	A Filter refers to a state that is used by a set object to filter out items from a set
	when creating a set of items to analyze.
*/
class Filter {

public:
	Filter(xercesc::DOMElement *filterElm);


	/**
	 * Returns the selected action for this filter.
	 * \return true if the selected action for this filter is "exclude",
	 * or false otherwise.
	 */
	bool IsExcluding(){return excluding;}

	/**
	 * Sets the action for this filter.  See IsExcluding().
	 */
	void SetExcluding(bool excluding)
	{ this->excluding = excluding; }

	/**
	 * Test the specified Item and return a boolean result.
	 * The return value reflects whether the item "passed" the filter.  E.g.
	 * if the item satisfied the state and the filter action is "include", then
	 * true is returned.  Or if the item did not satisfy the state and the filter
	 * Action is "exclude", then true is returned.  Otherwise false is returned.
	 */
	bool DoFilter(Item* item);	

	/**
	 * Get variable values used in the referenced state.
	 */
	VariableValueVector *GetVariableValues()
	{ return state->GetVariableValues(); }

private:

	/** Parse the provided filter from a definition file into a Filter object. */
	void Parse(xercesc::DOMElement* filterElm);

	/**
	 * A filter may have one of two values for its "action" attribute: "include" or
	 * "exclude".  This field represents the selected action for this filter.
	 */
	bool excluding;

	/**
	 * This filter's associated state.
	 */
	State *state;
};

typedef std::vector<Filter*> FilterVector;

/**
 * A handy dandy functor to assist in the use of filters with
 * STL algorithms.
 */
class FilterFunctor
{
public:
	FilterFunctor(Filter *filter):filter(filter){}
	bool operator()(Item *item);
private:
	Filter *filter;
};

#endif
