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/**
 * Copyright (c) 2015, Ecole des Mines de Nantes
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. 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.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *    This product includes software developed by the .
 * 4. Neither the name of the  nor the
 *    names of its contributors may be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY  ''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  BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
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package org.chocosolver.samples.real;

import org.chocosolver.samples.AbstractProblem;
import org.chocosolver.solver.Solver;
import org.chocosolver.solver.constraints.real.Ibex;
import org.chocosolver.solver.constraints.real.RealConstraint;
import org.chocosolver.solver.search.loop.monitors.SearchMonitorFactory;
import org.chocosolver.solver.search.strategy.selectors.values.RealDomainMiddle;
import org.chocosolver.solver.search.strategy.selectors.variables.Cyclic;
import org.chocosolver.solver.search.strategy.strategy.RealStrategy;
import org.chocosolver.solver.variables.IntVar;
import org.chocosolver.solver.variables.RealVar;
import org.chocosolver.solver.variables.VariableFactory;

/**
 * The cyclo hexan problem but hybrids finite/continuous problems
 * 

 *
 * @author Jean-Guillaume Fages, Charles Prud'homme
 * @since 18/07/12
 */
public class HybridCycloHexan extends AbstractProblem {

	RealVar[] vars;
	RealVar x, y, z;
	IntVar intx;

	@Override
	public void printDescription() {
		System.out.println("The CycloHexan problem consists in finding the 3D configuration of a cyclohexane molecule.\n"
				+ "It is decribed with a system of three non linear equations : \n"
				+ " y^2 * (1 + z^2) + z * (z - 24 * y) = -13 \n" +
				" x^2 * (1 + y^2) + y * (y - 24 * x) = -13 \n" +
				" z^2 * (1 + x^2) + x * (x - 24 * z) = -13 \n" +
				"This example comes from the Elisa project (LINA) examples. \n" +
				"This example restricts x to be integer, as an illustration to hybrid finite/continuous problems. \n" +
				"It has no solution. \n");
	}

	@Override
	public void createSolver() {
		solver = new Solver("HybridCycloHexan");
	}

	@Override
	public void buildModel() {
		double precision = 1.0e-3;
		// finite domain
		intx = VariableFactory.enumerated("x", new int[]{-10,-9,0,2,42}, solver);
		// continuous view
		x = VariableFactory.real(intx,precision);
		y = VariableFactory.real("y", -1.0e8, 1.0e8, precision, solver);
		z = VariableFactory.real("z", -1.0e8, 1.0e8, precision, solver);

		vars = new RealVar[]{x, y, z};
		solver.post(new RealConstraint(
				"CycloHexan",
				"{1}^2 * (1 + {2}^2) + {2} * ({2} - 24 * {1}) = -13;" +
						"{0}^2 * (1 + {1}^2) + {1} * ({1} - 24 * {0}) = -13;" +
						"{2}^2 * (1 + {0}^2) + {0} * ({0} - 24 * {2}) = -13",
				Ibex.HC4_NEWTON,
				vars)
		);
	}

	@Override
	public void configureSearch() {
		solver.set(new RealStrategy(vars, new Cyclic(), new RealDomainMiddle()));
		SearchMonitorFactory.limitTime(solver,10000);
	}

	@Override
	public void solve() {
		solver.findSolution();
	}

	@Override
	public void prettyOut() {
		solver.getIbex().release();
	}

	public static void main(String[] args) {
		new HybridCycloHexan().execute(args);
	}
}