//
// Cforall Version 1.0.0 Copyright (C) 2015 University of Waterloo
//
// The contents of this file are covered under the licence agreement in the
// file "LICENCE" distributed with Cforall.
//
// Cost.h --
//
// Author           : Richard C. Bilson
// Created On       : Sun May 17 09:39:50 2015
// Last Modified By : Aaron B. Moss
// Last Modified On : Fri Oct 05 14:32:00 2018
// Update Count     : 7
//

#pragma once

#include <iostream>

namespace ResolvExpr {
	class Cost {
	  private:
		Cost( int unsafeCost, int polyCost, int safeCost, int signCost, 
			int varCost, int specCost, int referenceCost );

	  public:
		Cost & incUnsafe( int inc = 1 );
		Cost & incPoly( int inc = 1 );
		Cost & incSafe( int inc = 1 );
		Cost & incSign( int inc = 1 );
		Cost & incVar( int inc = 1 );
		Cost & decSpec( int inc = 1 );
		Cost & incReference( int inc = 1 );

		int get_unsafeCost() const { return unsafeCost; }
		int get_polyCost() const { return polyCost; }
		int get_safeCost() const { return safeCost; }
		int get_signCost() const { return signCost; }
		int get_varCost() const { return varCost; }
		int get_specCost() const { return specCost; }
		int get_referenceCost() const { return referenceCost; }

		Cost operator+( const Cost &other ) const;
		Cost &operator+=( const Cost &other );
		bool operator<( const Cost &other ) const;
		bool operator==( const Cost &other ) const;
		bool operator!=( const Cost &other ) const;
		friend std::ostream &operator<<( std::ostream &os, const Cost &cost );
		// returns negative for *this < other, 0 for *this == other, positive for *this > other
		int compare( const Cost &other ) const;

		static const Cost zero;
		static const Cost infinity;

		static const Cost unsafe;
		static const Cost poly;
		static const Cost safe;
		static const Cost sign;
		static const Cost var;
		static const Cost spec;
		static const Cost reference;

	  private:
		int unsafeCost;     ///< Unsafe (narrowing) conversions
		int polyCost;       ///< Count of parameters and return values bound to some poly type
		int safeCost;       ///< Safe (widening) conversions
		int signCost;       ///< Count of safe sign conversions
		int varCost;        ///< Count of polymorphic type variables
		int specCost;       ///< Polymorphic type specializations (type assertions), negative cost
		int referenceCost;  ///< reference conversions
	};

	inline Cost::Cost( int unsafeCost, int polyCost, int safeCost, int signCost, 
			int varCost, int specCost, int referenceCost ) 
		: unsafeCost( unsafeCost ), polyCost( polyCost ), safeCost( safeCost ), signCost( signCost ), 
		  varCost( varCost ), specCost( specCost ), referenceCost( referenceCost ) {}

	inline Cost & Cost::incUnsafe( int inc ) {
		if ( *this == infinity ) return *this;
		unsafeCost += inc;
		return *this;
	}

	inline Cost & Cost::incPoly( int inc ) {
		if ( *this == infinity ) return *this;
		polyCost += inc;
		return *this;
	}

	inline Cost & Cost::incSafe( int inc ) {
		if ( *this == infinity ) return *this;
		safeCost += inc;
		return *this;
	}

	inline Cost & Cost::incSign( int inc ) {
		if ( *this == infinity ) return *this;
		signCost += inc;
		return *this;
	}

	inline Cost & Cost::incVar( int inc ) {
		if ( *this == infinity ) return *this;
		varCost += inc;
		return *this;
	}

	inline Cost& Cost::decSpec( int dec ) {
		if ( *this == infinity ) return *this;
		specCost -= dec;
		return *this;
	}

	inline Cost & Cost::incReference( int inc ) {
		if ( *this == infinity ) return *this;
		referenceCost += inc;
		return *this;
	}

	inline Cost Cost::operator+( const Cost &other ) const {
		if ( *this == infinity || other == infinity ) return infinity;
		return Cost{ 
			unsafeCost + other.unsafeCost, polyCost + other.polyCost, safeCost + other.safeCost, 
			signCost + other.signCost, varCost + other.varCost, specCost + other.specCost, 
			referenceCost + other.referenceCost };
	}

	inline Cost &Cost::operator+=( const Cost &other ) {
		if ( *this == infinity ) return *this;
		if ( other == infinity ) {
			*this = infinity;
			return *this;
		}
		unsafeCost += other.unsafeCost;
		polyCost += other.polyCost;
		safeCost += other.safeCost;
		signCost += other.signCost;
		varCost += other.varCost;
		specCost += other.specCost;
		referenceCost += other.referenceCost;
		return *this;
	}

	inline bool Cost::operator<( const Cost &other ) const {
		if ( *this == infinity ) return false;
		if ( other == infinity ) return true;

		if ( unsafeCost > other.unsafeCost ) {
			return false;
		} else if ( unsafeCost < other.unsafeCost ) {
			return true;
		} else if ( polyCost > other.polyCost ) {
			return false;
		} else if ( polyCost < other.polyCost ) {
			return true;
		} else if ( safeCost > other.safeCost ) {
			return false;
		} else if ( safeCost < other.safeCost ) {
			return true;
		} else if ( signCost > other.signCost ) {
			return false;
		} else if ( signCost < other.signCost ) {
			return true;
		} else if ( varCost > other.varCost ) {
			return false;
		} else if ( varCost < other.varCost ) {
			return true;
		} else if ( specCost > other.specCost ) {
			return false;
		} else if ( specCost > other.specCost ) {
			return true;
		} else if ( referenceCost > other.referenceCost ) {
			return false;
		} else if ( referenceCost < other.referenceCost ) {
			return true;
		} else {
			return false;
		} // if
	}

	inline int Cost::compare( const Cost &other ) const {
		if ( *this == infinity ) return +1;
		if ( other == infinity ) return -1;

		int c = unsafeCost - other.unsafeCost; if ( c ) return c;
		c = polyCost - other.polyCost; if ( c ) return c;
		c = safeCost - other.safeCost; if ( c ) return c;
		c = signCost - other.signCost; if ( c ) return c;
		c = varCost - other.varCost; if ( c ) return c;
		c = specCost - other.specCost; if ( c ) return c;
		return referenceCost - other.referenceCost;
	}

	inline bool Cost::operator==( const Cost &other ) const {
		return unsafeCost == other.unsafeCost
			&& polyCost == other.polyCost
			&& safeCost == other.safeCost
			&& signCost == other.signCost
			&& varCost == other.varCost
			&& specCost == other.specCost
			&& referenceCost == other.referenceCost;
	}

	inline bool Cost::operator!=( const Cost &other ) const {
		return !( *this == other );
	}

	inline std::ostream &operator<<( std::ostream &os, const Cost &cost ) {
		return os << "( " << cost.unsafeCost << ", " << cost.polyCost << ", " 
		          << cost.safeCost << ", " << cost.signCost << ", " 
				  << cost.varCost << ", " << cost.specCost << ", "
		          << cost.referenceCost << " )";
	}
} // namespace ResolvExpr

// Local Variables: //
// tab-width: 4 //
// mode: c++ //
// compile-command: "make install" //
// End: //