/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.xerces.impl.xs;

import org.apache.xerces.impl.xs.util.XSObjectListImpl;
import org.apache.xerces.xs.XSAnnotation;
import org.apache.xerces.xs.XSConstants;
import org.apache.xerces.xs.XSModelGroup;
import org.apache.xerces.xs.XSNamespaceItem;
import org.apache.xerces.xs.XSObjectList;

/**
 * Store schema model group declaration.
 *
 * @xerces.internal 
 *
 * @author Sandy Gao, IBM
 *
 * @version $Id: XSModelGroupImpl.java 699902 2008-09-28 21:40:49Z mrglavas $
 */
public class XSModelGroupImpl implements XSModelGroup {

    // types of model groups
    // REVISIT: can't use same constants as those for particles, because
    // there are place where the constants are used together. For example,
    // to check whether the content is an element or a sequence.
    public static final short MODELGROUP_CHOICE       = 101;
    public static final short MODELGROUP_SEQUENCE     = 102;
    public static final short MODELGROUP_ALL          = 103;

    // compositor of the model group
    public short fCompositor;

    // particles
    public XSParticleDecl[] fParticles = null;
    public int fParticleCount = 0;

    // this particle's optional annotations
    public XSObjectList fAnnotations = null;

    // whether this model group contains nothing
    public boolean isEmpty() {
        for (int i = 0; i < fParticleCount; i++) {
            if (!fParticles[i].isEmpty())
                return false;
        }
        return true;
    }

    /**
     * 3.8.6 Effective Total Range (all and sequence) and
     *       Effective Total Range (choice)
     * The following methods are used to return min/max range for a particle.
     * They are not exactly the same as it's described in the spec, but all the
     * values from the spec are retrievable by these methods.
     */
    public int minEffectiveTotalRange() {
        if (fCompositor == MODELGROUP_CHOICE)
            return minEffectiveTotalRangeChoice();
        else
            return minEffectiveTotalRangeAllSeq();
    }

    // return the sum of all min values of the particles
    private int minEffectiveTotalRangeAllSeq() {
        int total = 0;
        for (int i = 0; i < fParticleCount; i++)
            total += fParticles[i].minEffectiveTotalRange();
        return total;
    }

    // return the min of all min values of the particles
    private int minEffectiveTotalRangeChoice() {
        int min = 0, one;
        if (fParticleCount > 0)
            min = fParticles[0].minEffectiveTotalRange();

        for (int i = 1; i < fParticleCount; i++) {
            one = fParticles[i].minEffectiveTotalRange();
            if (one < min)
                min = one;
        }

        return min;
    }

    public int maxEffectiveTotalRange() {
        if (fCompositor == MODELGROUP_CHOICE)
            return maxEffectiveTotalRangeChoice();
        else
            return maxEffectiveTotalRangeAllSeq();
    }

    // if one of the max value of the particles is unbounded, return unbounded;
    // otherwise return the sum of all max values
    private int maxEffectiveTotalRangeAllSeq() {
        int total = 0, one;
        for (int i = 0; i < fParticleCount; i++) {
            one = fParticles[i].maxEffectiveTotalRange();
            if (one == SchemaSymbols.OCCURRENCE_UNBOUNDED)
                return SchemaSymbols.OCCURRENCE_UNBOUNDED;
            total += one;
        }
        return total;
    }

    // if one of the max value of the particles is unbounded, return unbounded;
    // otherwise return the max of all max values
    private int maxEffectiveTotalRangeChoice() {
        int max = 0, one;
        if (fParticleCount > 0) {
            max = fParticles[0].maxEffectiveTotalRange();
            if (max == SchemaSymbols.OCCURRENCE_UNBOUNDED)
                return SchemaSymbols.OCCURRENCE_UNBOUNDED;
        }

        for (int i = 1; i < fParticleCount; i++) {
            one = fParticles[i].maxEffectiveTotalRange();
            if (one == SchemaSymbols.OCCURRENCE_UNBOUNDED)
                return SchemaSymbols.OCCURRENCE_UNBOUNDED;
            if (one > max)
                max = one;
        }
        return max;
    }

    /**
     * get the string description of this particle
     */
    private String fDescription = null;
    public String toString() {
    	// REVISIT: Commented code may help to eliminate redundant parentheses (test first before committing)
        if (fDescription == null) {
            StringBuffer buffer = new StringBuffer();
            if (fCompositor == MODELGROUP_ALL)
                buffer.append("all(");
            else  //if (fMinOccurs != 1 || fMaxOccurs != 1)
                buffer.append('(');
            if (fParticleCount > 0)
                buffer.append(fParticles[0].toString());
            for (int i = 1; i < fParticleCount; i++) {
                if (fCompositor == MODELGROUP_CHOICE)
                    buffer.append('|');
                else
                    buffer.append(',');
                buffer.append(fParticles[i].toString());
            }
            //if (fCompositor == MODELGROUP_ALL || fMinOccurs != 1 || fMaxOccurs != 1)
                  buffer.append(')');
            fDescription = buffer.toString();
        }
        return fDescription;
    }

    public void reset(){
        fCompositor = MODELGROUP_SEQUENCE;
        fParticles = null;
        fParticleCount = 0;
        fDescription = null;
        fAnnotations = null;
    }

    /**
     * Get the type of the object, i.e ELEMENT_DECLARATION.
     */
    public short getType() {
        return XSConstants.MODEL_GROUP;
    }

    /**
     * The <code>name</code> of this <code>XSObject</code> depending on the
     * <code>XSObject</code> type.
     */
    public String getName() {
        return null;
    }

    /**
     * The namespace URI of this node, or <code>null</code> if it is
     * unspecified.  defines how a namespace URI is attached to schema
     * components.
     */
    public String getNamespace() {
        return null;
    }

    /**
     * {compositor} One of all, choice or sequence. The valid constants values
     * are: ALL, CHOICE, SEQUENCE.
     */
    public short getCompositor() {
        if (fCompositor == MODELGROUP_CHOICE)
            return XSModelGroup.COMPOSITOR_CHOICE;
        else if (fCompositor == MODELGROUP_SEQUENCE)
            return XSModelGroup.COMPOSITOR_SEQUENCE;
        else
            return XSModelGroup.COMPOSITOR_ALL;
    }

    /**
     * {particles} A list of particles
     */
    public XSObjectList getParticles() {
        return new XSObjectListImpl(fParticles, fParticleCount);
    }

    /**
     * Optional. Annotation.
     */
    public XSAnnotation getAnnotation() {
        return (fAnnotations != null) ? (XSAnnotation) fAnnotations.item(0) : null;
    }

    /**
     * Optional. Annotations.
     */
    public XSObjectList getAnnotations() {
        return (fAnnotations != null) ? fAnnotations : XSObjectListImpl.EMPTY_LIST;
    }

    /**
     * @see org.apache.xerces.xs.XSObject#getNamespaceItem()
     */
    public XSNamespaceItem getNamespaceItem() {
        return null;
    }

} // class XSModelGroupImpl
