/*
 * Copyright (c) 2007 Mozilla Foundation
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 */

package nu.validator.checker;

import java.util.HashSet;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Set;

import org.xml.sax.Attributes;
import org.xml.sax.Locator;
import org.xml.sax.SAXException;

public class UsemapChecker extends Checker {

    private final Map<String, Locator> usemapLocationsByName = new LinkedHashMap<>();

    private final Set<String> mapNames = new HashSet<>();

    private Locator locator = null;

    public UsemapChecker() {
    }

    /**
     * @see nu.validator.checker.Checker#startElement(java.lang.String,
     *      java.lang.String, java.lang.String, org.xml.sax.Attributes)
     */
    @Override
    public void startElement(String uri, String localName, String qName,
            Attributes atts) throws SAXException {
        if ("http://www.w3.org/1999/xhtml" == uri) {
            if ("map" == localName) {
                String name = atts.getValue("", "name");
                if (name != null && !"".equals(name)) {
                    mapNames.add(name);
                }
            } else if ("img" == localName || "object" == localName) {
                String usemap = atts.getValue("", "usemap");
                if (usemap != null) {
                    int hashIndex = usemap.indexOf('#');
                    if ((hashIndex > -1) && (hashIndex < usemap.length() - 1)) {
                        // XXX not complaining about bad values here as
                        // the schema takes care of that.
                        String ref = usemap.substring(hashIndex + 1);
                        usemapLocationsByName.put(ref,
                                new LocatorImpl(locator));
                    }
                }
            }
        }
    }

    /**
     * @see org.xml.sax.helpers.XMLFilterImpl#endDocument()
     */
    @Override
    public void endDocument() throws SAXException {
        for (Map.Entry<String, Locator> entry : usemapLocationsByName.entrySet()) {
            if (!mapNames.contains(entry.getKey())) {
                err("The hash-name reference in attribute “usemap”"
                    + " referred to “"
                        + entry.getKey()
                        + "”, but there is no “map” element"
                        + " with a “name” attribute with that value.",
                        entry.getValue());
            }
        }
    }

    /**
     * @see org.xml.sax.helpers.XMLFilterImpl#startDocument()
     */
    @Override
    public void startDocument() throws SAXException {
        usemapLocationsByName.clear();
        mapNames.clear();
    }

    /**
     * @see org.xml.sax.helpers.XMLFilterImpl#setDocumentLocator(org.xml.sax.Locator)
     */
    @Override
    public void setDocumentLocator(Locator locator) {
        this.locator = locator;
    }

    /**
     * @see nu.validator.checker.Checker#reset()
     */
    @Override
    public void reset() {
        usemapLocationsByName.clear();
        mapNames.clear();
    }

}
