/*
 *    GeoTools - The Open Source Java GIS Toolkit
 *    http://geotools.org
 *
 *    (C) 2014, Open Source Geospatial Foundation (OSGeo)
 *
 *    This library is free software; you can redistribute it and/or
 *    modify it under the terms of the GNU Lesser General Public
 *    License as published by the Free Software Foundation;
 *    version 2.1 of the License.
 *
 *    This library is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *    Lesser General Public License for more details.
 */
package org.geotools.styling.css.selector;

import java.util.ArrayList;
import java.util.LinkedHashSet;
import java.util.List;
import java.util.Set;

public class PseudoClass extends Selector {

    public static Selector combineAnd(List<PseudoClass> selectors, Object ctx) {
        // just remove duplicate pseudo classes
        return new And(new ArrayList<>(new LinkedHashSet<Selector>(selectors)));
	}

	public static final PseudoClass ROOT = new PseudoClass(null, -1) {
		public String toString() {
			return "ROOT";
		};
	};

	String className;

	int number = -1;

	public String getClassName() {
		return className;
	}

	public int getNumber() {
		return number;
	}

	public static PseudoClass newPseudoClass(String className) {
		return newPseudoClass(className, -1);
	}
	
	public static PseudoClass newPseudoClass(String className, int number) {
		return new PseudoClass(className, number);
	}


	private PseudoClass(String className, int number) {
		this.className = className;
		this.number = number;
	}

	@Override
	public String toString() {
		return "PseudoClass [className=" + className + ", number=" + number
				+ "]";
	}

	@Override
	public int hashCode() {
		final int prime = 31;
		int result = 1;
		result = prime * result
				+ ((className == null) ? 0 : className.hashCode());
		result = prime * result + number;
		return result;
	}

	@Override
	public boolean equals(Object obj) {
		if (this == obj)
			return true;
		if (obj == null)
			return false;
		if (getClass() != obj.getClass())
			return false;
		PseudoClass other = (PseudoClass) obj;
		if (className == null) {
			if (other.className != null)
				return false;
		} else if (!className.equals(other.className))
			return false;
		if (number != other.number)
			return false;
		return true;
	}

	@Override
	public Specificity getSpecificity() {
		if (number < 0) {
			return Specificity.PSEUDO_1;
		} else {
			return Specificity.PSEUDO_2;
		}
	}

	public Object accept(SelectorVisitor visitor) {
		return visitor.visit(this);
	}

    /**
     * Returns true if this pseudo class is equals, or contains, the other
     * 
     * @param pc
     * @return
     */
    public boolean contains(PseudoClass pc) {
        if (this.equals(PseudoClass.ROOT)) {
            return true;
        } else if (pc == null || PseudoClass.ROOT.equals(pc)) {
            return false;
        }

        // contain all case, or same class
        if ("symbol".equals(className) || className.equals(pc.className)) {
            return number < 0 || pc.number == number;
        }

        return false;
    }

    /**
     * Returns the most specific pseudo class in the set, or null if the set contains inconsistent
     * pseudo classes (e.g., "mark" and "fill")
     * 
     * @param pseudoClasses
     * @return
     */
    public static PseudoClass getMostSpecific(Set<PseudoClass> pseudoClasses) {
        PseudoClass mostSpecific = null;
        for (PseudoClass pc : pseudoClasses) {
            if (mostSpecific == null || mostSpecific.contains(pc)) {
                mostSpecific = pc;
            } else if (!pc.contains(mostSpecific)) {
                // found two that are not compatible
                return null;
            }
        }

        return mostSpecific;
    }

}