/**
 * 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.cxf.jaxrs.provider;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.lang.annotation.Annotation;
import java.lang.reflect.Type;
import java.nio.charset.StandardCharsets;

import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.MultivaluedMap;
import javax.ws.rs.ext.MessageBodyReader;
import javax.ws.rs.ext.MessageBodyWriter;

import org.apache.cxf.helpers.IOUtils;
import org.apache.cxf.jaxrs.utils.HttpUtils;

public class StringTextProvider extends AbstractConfigurableProvider
    implements MessageBodyReader<String>, MessageBodyWriter<String> {
    private int bufferSize = IOUtils.DEFAULT_BUFFER_SIZE;
    public boolean isReadable(Class<?> type, Type genericType, Annotation[] annotations, MediaType mt) {
        return String.class == type;
    }

    public String readFrom(Class<String> type, Type genType, Annotation[] anns, MediaType mt, 
                      MultivaluedMap<String, String> headers, InputStream is) throws IOException {
        return IOUtils.toString(is, HttpUtils.getEncoding(mt, StandardCharsets.UTF_8.name()));
    }

    public long getSize(String t, Class<?> type, Type genericType, Annotation[] annotations, MediaType mt) {
        return -1;
    }

    public boolean isWriteable(Class<?> type, Type genericType, Annotation[] annotations, MediaType mt) {
        return String.class == type;
    }

    public void writeTo(String obj, Class<?> type, Type genType, Annotation[] anns, 
                        MediaType mt, MultivaluedMap<String, Object> headers,
                        OutputStream os) throws IOException {
        String encoding = HttpUtils.getSetEncoding(mt, headers, StandardCharsets.UTF_8.name());
        //REVISIT try to avoid instantiating the whole byte array
        byte[] bytes = obj.getBytes(encoding);
        if (bytes.length > bufferSize) {
            int pos = 0;
            while (pos < bytes.length) {
                int bl = bytes.length - pos;
                if (bl > bufferSize) {
                    bl = bufferSize;
                }
                os.write(bytes, pos, bl);
                pos += bl;
            }
        } else {
            os.write(bytes);
        }
    }
    public void setBufferSize(int bufferSize) {
        this.bufferSize = bufferSize;
    }
}
