/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 * 
 * Copyright 1997-2007 Sun Microsystems, Inc. All rights reserved.
 * 
 * Portions Copyright Apache Software Foundation.
 * 
 * The contents of this file are subject to the terms of either the GNU
 * General Public License Version 2 only ("GPL") or the Common Development
 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License. You can obtain
 * a copy of the License at https://glassfish.dev.java.net/public/CDDL+GPL.html
 * or glassfish/bootstrap/legal/LICENSE.txt.  See the License for the specific
 * language governing permissions and limitations under the License.
 * 
 * When distributing the software, include this License Header Notice in each
 * file and include the License file at glassfish/bootstrap/legal/LICENSE.txt.
 * Sun designates this particular file as subject to the "Classpath" exception
 * as provided by Sun in the GPL Version 2 section of the License file that
 * accompanied this code.  If applicable, add the following below the License
 * Header, with the fields enclosed by brackets [] replaced by your own
 * identifying information: "Portions Copyrighted [year]
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 * 
 * If you wish your version of this file to be governed by only the CDDL or
 * only the GPL Version 2, indicate your decision by adding "[Contributor]
 * elects to include this software in this distribution under the [CDDL or GPL
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 */


package org.apache.coyote.tomcat5;

import java.io.BufferedReader;
import java.io.IOException;
import org.apache.catalina.util.StringManager;


/**
 * Coyote implementation of the buffred reader.
 * 
 * @author Remy Maucherat
 */
public class CoyoteReader
    extends BufferedReader {


    // -------------------------------------------------------------- Constants


    private static final char[] LINE_SEP = { '\r', '\n' };
    private static final int MAX_LINE_LENGTH = 4096;

    /**
     * The string manager for this package.
     */
    private static final StringManager sm =
        StringManager.getManager(Constants.Package);


    // ----------------------------------------------------- Instance Variables


    protected InputBuffer ib;

    protected char[] lineBuffer = null;


    // ----------------------------------------------------------- Constructors


    public CoyoteReader(InputBuffer ib) {
        super(ib, 1);
        this.ib = ib;
    }

    // --------------------------------------------------------- Public Methods


    /**
    * Prevent cloning the facade.
    */
    protected Object clone()
        throws CloneNotSupportedException {
        throw new CloneNotSupportedException();
    }
    
    
    // -------------------------------------------------------- Package Methods


    /**
     * Clear facade.
     */
    void clear() {
        ib = null;
    }


    // --------------------------------------------------------- Reader Methods


    public void close()
        throws IOException {
        // Disallow operation if the object has gone out of scope
        if (ib == null) {
            throw new IllegalStateException(
                sm.getString("object.invalidScope"));
        }
        ib.close();
    }


    public int read()
        throws IOException {
        // Disallow operation if the object has gone out of scope
        if (ib == null) {
            throw new IllegalStateException(
                sm.getString("object.invalidScope"));
        }
        return ib.read();
    }


    public int read(char[] cbuf)
        throws IOException {
        // Disallow operation if the object has gone out of scope
        if (ib == null) {
            throw new IllegalStateException(
                sm.getString("object.invalidScope"));
        }
        return ib.read(cbuf, 0, cbuf.length);
    }


    public int read(char[] cbuf, int off, int len)
        throws IOException {
        // Disallow operation if the object has gone out of scope
        if (ib == null) {
            throw new IllegalStateException(
                sm.getString("object.invalidScope"));
        }
        return ib.read(cbuf, off, len);
    }


    public long skip(long n)
        throws IOException {
        // Disallow operation if the object has gone out of scope
        if (ib == null) {
            throw new IllegalStateException(
                sm.getString("object.invalidScope"));
        }
        return ib.skip(n);
    }


    public boolean ready()
        throws IOException {
        // Disallow operation if the object has gone out of scope
        if (ib == null) {
            throw new IllegalStateException(
                sm.getString("object.invalidScope"));
        }
        return ib.ready();
    }


    public boolean markSupported() {
        // Disallow operation if the object has gone out of scope
        if (ib == null) {
            throw new IllegalStateException(
                sm.getString("object.invalidScope"));
        }
        return true;
    }


    public void mark(int readAheadLimit)
        throws IOException {
        // Disallow operation if the object has gone out of scope
        if (ib == null) {
            throw new IllegalStateException(
                sm.getString("object.invalidScope"));
        }
        ib.mark(readAheadLimit);
    }


    public void reset()
        throws IOException {
        // Disallow operation if the object has gone out of scope
        if (ib == null) {
            throw new IllegalStateException(
                sm.getString("object.invalidScope"));
        }
        ib.reset();
    }


    public String readLine()
        throws IOException {

        // Disallow operation if the object has gone out of scope
        if (ib == null) {
            throw new IllegalStateException(
                sm.getString("object.invalidScope"));
        }

        if (lineBuffer == null) {
            lineBuffer = new char[MAX_LINE_LENGTH];
        }

        String result = null;

        int pos = 0;
        int end = -1;
        int skip = -1;
        StringBuffer aggregator = null;
        while (end < 0) {
            mark(MAX_LINE_LENGTH);
            while ((pos < MAX_LINE_LENGTH) && (end < 0)) {
                int nRead = read(lineBuffer, pos, MAX_LINE_LENGTH - pos);
                if (nRead < 0) {
                    if (pos == 0) {
                        return null;
                    }
                    end = pos;
                    skip = pos;
                }
                for (int i = pos; (i < (pos + nRead)) && (end < 0); i++) {
                    if (lineBuffer[i] == LINE_SEP[0]) {
                        end = i;
                        skip = i + 1;
                        char nextchar;
                        if (i == (pos + nRead - 1)) {
                            nextchar = (char) read();
                        } else {
                            nextchar = lineBuffer[i+1];
                        }
                        if (nextchar == LINE_SEP[1]) {
                            skip++;
                        }
                    } else if (lineBuffer[i] == LINE_SEP[1]) {
                        end = i;
                        skip = i + 1;
                    }
                }
                if (nRead > 0) {
                    pos += nRead;
                }
            }
            if (end < 0) {
                if (aggregator == null) {
                    aggregator = new StringBuffer();
                }
                aggregator.append(lineBuffer);
                pos = 0;
            } else {
                reset();
                skip(skip);
            }
        }

        if (aggregator == null) {
            result = new String(lineBuffer, 0, end);
        } else {
            aggregator.append(lineBuffer, 0, end);
            result = aggregator.toString();
        }

        return result;

    }


}
