Copyright Microsoft Corporation
Licensed 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.
/**
 * Copyright Microsoft Corporation
 * 
 * Licensed 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 com.microsoft.azure.storage.file;

import java.io.IOException;
import java.io.InputStream;
import java.net.URISyntaxException;
import java.text.ParseException;
import java.util.Stack;

import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;

import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.DefaultHandler;

import com.microsoft.azure.storage.Constants;
import com.microsoft.azure.storage.StorageException;
import com.microsoft.azure.storage.core.ListResponse;
import com.microsoft.azure.storage.core.SR;
import com.microsoft.azure.storage.core.Utility;

RESERVED FOR INTERNAL USE. A class used to deserialize a list of shares.
/**
 * RESERVED FOR INTERNAL USE. A class used to deserialize a list of shares.
 */
final class ShareListHandler extends DefaultHandler {

    private final Stack<String> elementStack = new Stack<String>();
    private StringBuilder bld = new StringBuilder();

    private final CloudFileClient serviceClient;

    private final ListResponse<CloudFileShare> response = new ListResponse<CloudFileShare>();
    private FileShareAttributes attributes;
    private String shareName;
    private String snapshotID;

    private ShareListHandler(CloudFileClient serviceClient) {
        this.serviceClient = serviceClient;
    }

    
Parses a ShareListResponse form the given XML stream. 
Params:
serviceClient – 
           a reference to the client object associated with this object.
stream – 
           the stream from which to parse the share list
Throws:
SAXException – 
ParserConfigurationException – 
IOException – /**
     * Parses a {@link ShareListResponse} form the given XML stream.
     * 
     * @param serviceClient
     *            a reference to the client object associated with this object.
     * @param stream
     *            the stream from which to parse the share list
     * @throws SAXException
     * @throws ParserConfigurationException
     * @throws IOException
     */
    protected static ListResponse<CloudFileShare> getShareList(final InputStream stream,
            final CloudFileClient serviceClient) throws ParserConfigurationException, SAXException, IOException {
        SAXParser saxParser = Utility.getSAXParser();
        ShareListHandler handler = new ShareListHandler(serviceClient);
        saxParser.parse(stream, handler);

        return handler.response;
    }

    @Override
    public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException {
        this.elementStack.push(localName);

        if (FileConstants.SHARE_ELEMENT.equals(localName)) {
            this.shareName = Constants.EMPTY_STRING;
            this.snapshotID = null;
            this.attributes = new FileShareAttributes();
        }
    }

    @Override
    public void endElement(String uri, String localName, String qName) throws SAXException {
        String currentNode = this.elementStack.pop();

        // if the node popped from the stack and the localName don't match, the xml document is improperly formatted
        if (!localName.equals(currentNode)) {
            throw new SAXException(SR.INVALID_RESPONSE_RECEIVED);
        }

        String parentNode = null;
        if (!this.elementStack.isEmpty()) {
            parentNode = this.elementStack.peek();
        }

        String value = this.bld.toString();
        if (value.isEmpty()) {
            value = null;
        }

        if (FileConstants.SHARE_ELEMENT.equals(currentNode)) {
            try {
                CloudFileShare retShare = this.serviceClient.getShareReference(this.shareName);
                retShare.setMetadata(this.attributes.getMetadata());
                retShare.setProperties(this.attributes.getProperties());
                retShare.snapshotID = this.snapshotID;

                this.response.getResults().add(retShare);
            }
            catch (URISyntaxException e) {
                throw new SAXException(e);
            }
            catch (StorageException e) {
                throw new SAXException(e);
            }

        }
        else if (ListResponse.ENUMERATION_RESULTS.equals(parentNode)) {
            if (Constants.PREFIX_ELEMENT.equals(currentNode)) {
                this.response.setPrefix(value);
            }
            else if (Constants.MARKER_ELEMENT.equals(currentNode)) {
                this.response.setMarker(value);
            }
            else if (Constants.NEXT_MARKER_ELEMENT.equals(currentNode)) {
                this.response.setNextMarker(value);
            }
            else if (Constants.MAX_RESULTS_ELEMENT.equals(currentNode)) {
                this.response.setMaxResults(Integer.parseInt(value));
            }
        }
        else if (FileConstants.SHARE_ELEMENT.equals(parentNode)) {
            if (Constants.NAME_ELEMENT.equals(currentNode)) {
                this.shareName = value;
            }
            else if (Constants.QueryConstants.SNAPSHOT.equals(currentNode.toLowerCase())) {
                this.snapshotID = value;
            }
        }
        else if (Constants.PROPERTIES.equals(parentNode)) {
            try {
                getProperties(currentNode, value);
            }
            catch (ParseException e) {
                throw new SAXException(e);
            }
        }
        else if (Constants.METADATA_ELEMENT.equals(parentNode)) {
            if (value == null) {
                value = "";
            }
            this.attributes.getMetadata().put(currentNode, value);
        }

        this.bld = new StringBuilder();
    }

    @Override
    public void characters(char ch[], int start, int length) throws SAXException {
        this.bld.append(ch, start, length);
    }

    private void getProperties(String currentNode, String value) throws ParseException {
        if (currentNode.equals(Constants.LAST_MODIFIED_ELEMENT)) {
            this.attributes.getProperties().setLastModified(Utility.parseRFC1123DateFromStringInGMT(value));
        }
        else if (currentNode.equals(Constants.ETAG_ELEMENT)) {
            this.attributes.getProperties().setEtag(Utility.formatETag(value));
        }
        else if (currentNode.equals(FileConstants.SHARE_QUOTA_ELEMENT)) {
            this.attributes.getProperties().setShareQuota(Utility.isNullOrEmpty(value) ? null : Integer.parseInt(value));
        }
    }
}