001// Licensed under the Apache License, Version 2.0 (the "License");
002// you may not use this file except in compliance with the License.
003// You may obtain a copy of the License at
004//
005//     http://www.apache.org/licenses/LICENSE-2.0
006//
007// Unless required by applicable law or agreed to in writing, software
008// distributed under the License is distributed on an "AS IS" BASIS,
009// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
010// See the License for the specific language governing permissions and
011// limitations under the License.
012
013package org.apache.tapestry5.internal.util;
014
015import org.apache.tapestry5.*;
016
017import java.util.Map;
018
019public class SelectModelRenderer implements SelectModelVisitor
020{
021    private final MarkupWriter writer;
022
023    private final ValueEncoder encoder;
024
025    private final boolean raw;
026
027    public SelectModelRenderer(final MarkupWriter writer, ValueEncoder encoder, boolean raw)
028    {
029        this.writer = writer;
030        this.encoder = encoder;
031        this.raw = raw;
032    }
033
034    public void beginOptionGroup(OptionGroupModel groupModel)
035    {
036        writer.element("optgroup", "label", groupModel.getLabel());
037
038        writeDisabled(groupModel.isDisabled());
039        writeAttributes(groupModel.getAttributes());
040    }
041
042    public void endOptionGroup(OptionGroupModel groupModel)
043    {
044        writer.end(); // select
045    }
046
047    @SuppressWarnings("unchecked")
048    public void option(OptionModel optionModel)
049    {
050        Object optionValue = optionModel.getValue();
051
052        String clientValue = encoder.toClient(optionValue);
053
054        writer.element("option", "value", clientValue);
055
056        if (isOptionSelected(optionModel, clientValue)) writer.attributes("selected", "selected");
057
058        writeDisabled(optionModel.isDisabled());
059        writeAttributes(optionModel.getAttributes());
060
061
062        if (raw)
063        {
064            writer.writeRaw(optionModel.getLabel());
065        } else
066        {
067            writer.write(optionModel.getLabel());
068        }
069
070        writer.end();
071    }
072
073    private void writeDisabled(boolean disabled)
074    {
075        if (disabled) writer.attributes("disabled", "disabled");
076    }
077
078    private void writeAttributes(Map<String, String> attributes)
079    {
080        if (attributes == null) return;
081
082        for (Map.Entry<String, String> e : attributes.entrySet())
083            writer.attributes(e.getKey(), e.getValue());
084    }
085
086    /**
087     * If true, then the selected attribute will be written. This implementation always returns false.
088     */
089    protected boolean isOptionSelected(OptionModel optionModel, String clientValue)
090    {
091        return false;
092    }
093
094}