/*
 * Copyright 2011 The Netty Project
 *
 * The Netty Project 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 io.netty.handler.codec.http;

import java.nio.charset.Charset;

import io.netty.buffer.ChannelBuffer;
import io.netty.util.CharsetUtil;

/**
 * Shared Static object between HttpMessageDecoder, HttpPostRequestDecoder and HttpPostRequestEncoder
 */
final class HttpPostBodyUtil {

    public static int chunkSize = 8096;
    /**
     * HTTP content disposition header name.
     */
    public static final String CONTENT_DISPOSITION = "Content-Disposition";

    public static final String NAME = "name";

    public static final String FILENAME = "filename";

    /**
     * Content-disposition value for form data.
     */
    public static final String FORM_DATA = "form-data";

    /**
     * Content-disposition value for file attachment.
     */
    public static final String ATTACHMENT = "attachment";

    /**
     * Content-disposition value for file attachment.
     */
    public static final String FILE = "file";

    /**
     * HTTP content type body attribute for multiple uploads.
     */
    public static final String MULTIPART_MIXED = "multipart/mixed";

    /**
     * Charset for 8BIT
     */
    public static final Charset ISO_8859_1 = CharsetUtil.ISO_8859_1;

    /**
     * Charset for 7BIT
     */
    public static final Charset US_ASCII = CharsetUtil.US_ASCII;

    /**
     * Default Content-Type in binary form
     */
    public static final String DEFAULT_BINARY_CONTENT_TYPE = "application/octet-stream";

    /**
     * Default Content-Type in Text form
     */
    public static final String DEFAULT_TEXT_CONTENT_TYPE = "text/plain";

    /**
     * Allowed mechanism for multipart
     * mechanism := "7bit"
                  / "8bit"
                  / "binary"
       Not allowed: "quoted-printable"
                  / "base64"
     */
    public enum TransferEncodingMechanism {
        /**
         * Default encoding
         */
        BIT7("7bit"),
        /**
         * Short lines but not in ASCII - no encoding
         */
        BIT8("8bit"),
        /**
         * Could be long text not in ASCII - no encoding
         */
        BINARY("binary");

        public String value;

        TransferEncodingMechanism(String value) {
            this.value = value;
        }

        TransferEncodingMechanism() {
            value = name();
        }

        @Override
        public String toString() {
            return value;
        }
    }

    private HttpPostBodyUtil() {
    }

    /**
     * Exception when NO Backend Array is found
     */ 
    static class SeekAheadNoBackArray extends Exception {
        private static final long serialVersionUID = -630418804938699495L;
    }

    /**
     * This class intends to decrease the CPU in seeking ahead some bytes in 
     * HttpPostRequestDecoder
     */
    static class SeekAheadOptimize {
        byte[] bytes;

        int readerIndex;

        int pos;

        int limit;

        ChannelBuffer buffer;

        /**
         * @param buffer
         */
        SeekAheadOptimize(ChannelBuffer buffer)
                throws SeekAheadNoBackArray {
            if (! buffer.hasArray()) {
                throw new SeekAheadNoBackArray();
            }
            this.buffer = buffer;
            this.bytes = buffer.array();
            this.pos = this.readerIndex = buffer.readerIndex();
            this.limit = buffer.writerIndex();
        }
        /**
         * 
         * @param minus this value will be used as (currentPos - minus) to set
         *      the current readerIndex in the buffer. 
         */
        void setReadPosition(int minus) {
            pos -= minus;
            readerIndex = pos;
            buffer.readerIndex(readerIndex);
        }
        
        void clear() {
            this.buffer = null;
            this.bytes = null;
            this.limit = 0;
            this.pos = 0;
            this.readerIndex = 0;
        }
    }

    /**
     * Find the first non whitespace
     * @param sb
     * @param offset
     * @return the rank of the first non whitespace
     */
    static int findNonWhitespace(String sb, int offset) {
        int result;
        for (result = offset; result < sb.length(); result ++) {
            if (!Character.isWhitespace(sb.charAt(result))) {
                break;
            }
        }
        return result;
    }

    /**
     * Find the first whitespace
     * @param sb
     * @param offset
     * @return the rank of the first whitespace
     */
    static int findWhitespace(String sb, int offset) {
        int result;
        for (result = offset; result < sb.length(); result ++) {
            if (Character.isWhitespace(sb.charAt(result))) {
                break;
            }
        }
        return result;
    }

    /**
     * Find the end of String
     * @param sb
     * @return the rank of the end of string
     */
    static int findEndOfString(String sb) {
        int result;
        for (result = sb.length(); result > 0; result --) {
            if (!Character.isWhitespace(sb.charAt(result - 1))) {
                break;
            }
        }
        return result;
    }

}

@@ -3173,16 +3173,25 @@
 ackArray
+Exception
  extends
@@ -3704,16 +3704,25 @@
 ackArray
+Exception
  %7B%0A     
@@ -3797,24 +3797,33 @@
 dNoBackArray
+Exception
 ();%0A        

Add Exception to name of the Exception ;-)