/* Woodstox XML processor
 *
 * Copyright (c) 2004- Tatu Saloranta, tatu.saloranta@iki.fi
 *
 * Licensed under the License specified in the file LICENSE which is
 * included with the source code.
 * You may not use this file except in compliance with the License.
 *
 * 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 com.ctc.wstx.dtd;

import java.net.URI;

Simple key object class, used for accessing (external) DTDs when stored for
caching. Main idea is that the primary id of a DTD (public or system id;
latter normalized if possible)
has to match, as well as couple of on/off settings for parsing (namespace
support, text normalization).
Latter restriction is needed since although DTDs do not deal
with (or understand) namespaces, some parsing is done to be able to validate
namespace aware/non-aware documents, and handling differs between the two.
As to primary key part, public id is used if one was defined; if so,
comparison is String equality. If not, then system id is compared: system
id has to be expressed as URL if so.
/**
 * Simple key object class, used for accessing (external) DTDs when stored for
 * caching. Main idea is that the primary id of a DTD (public or system id;
 * latter normalized if possible)
 * has to match, as well as couple of on/off settings for parsing (namespace
 * support, text normalization).
 * Latter restriction is needed since although DTDs do not deal
 * with (or understand) namespaces, some parsing is done to be able to validate
 * namespace aware/non-aware documents, and handling differs between the two.
 * As to primary key part, public id is used if one was defined; if so,
 * comparison is String equality. If not, then system id is compared: system
 * id has to be expressed as URL if so.
 */
public final class DTDId
{
    protected final String mPublicId;

    protected final URI mSystemId;

    protected final int mConfigFlags;

    protected final boolean mXml11;

    protected int mHashCode = 0;

    /*
    ///////////////////////////////////////////////////////////////////////
    // Life-cycle:
    ///////////////////////////////////////////////////////////////////////
     */

    private DTDId(String publicId, URI systemId, int configFlags, boolean xml11)
    {
        mPublicId = publicId;
        mSystemId = systemId;
        mConfigFlags = configFlags;
        mXml11 = xml11;
    }

    public static DTDId constructFromPublicId(String publicId, int configFlags,
                                              boolean xml11)
    {
        if (publicId == null || publicId.length() == 0) {
            throw new IllegalArgumentException("Empty/null public id.");
        }
        return new DTDId(publicId, null, configFlags, xml11);
    }

    public static DTDId constructFromSystemId(URI systemId, int configFlags,
                                              boolean xml11)
    {
        if (systemId == null) {
            throw new IllegalArgumentException("Null system id.");
        }
        return new DTDId(null, systemId, configFlags, xml11);
    }

    public static DTDId construct(String publicId, URI systemId, int configFlags, boolean xml11)
    {
        if (publicId != null && publicId.length() > 0) {
            return new DTDId(publicId, null, configFlags, xml11);
        }
        if (systemId == null) {
            throw new IllegalArgumentException("Illegal arguments; both public and system id null/empty.");
        }
        return new DTDId(null, systemId, configFlags, xml11);
    }

    /*
    ///////////////////////////////////////////////////////////////////////
    // Overridden standard methods
    ///////////////////////////////////////////////////////////////////////
     */

    @Override
    public int hashCode() {
        int hash = mHashCode;
        if (hash == 0) {
            hash = mConfigFlags;
            if (mPublicId != null) {
                hash ^= mPublicId.hashCode();
            } else {
                hash ^= mSystemId.hashCode();
            }
            if (mXml11) {
                hash ^= 1;
            }
            mHashCode = hash;
        }
        return hash;
    }

    @Override
    public String toString() {
        StringBuffer sb = new StringBuffer(60);
        sb.append("Public-id: ");
        sb.append(mPublicId);
        sb.append(", system-id: ");
        sb.append(mSystemId);
        sb.append(" [config flags: 0x");
        sb.append(Integer.toHexString(mConfigFlags));
        sb.append("], xml11: ");
        sb.append(mXml11);
        return sb.toString();
    }

    @Override
    public boolean equals(Object o)
    {
        if (o == this) return true;
        if (o == null || o.getClass() != getClass()) return false;
        DTDId other = (DTDId) o;
        if (other.mConfigFlags != mConfigFlags
            || other.mXml11 != mXml11) {
            return false;
        }
        if (mPublicId != null) {
            String op = other.mPublicId;
            return (op != null) && op.equals(mPublicId);
        }
        return mSystemId.equals(other.mSystemId);
    }
}