/*

 * Copyright 2005-2008 Sun Microsystems, Inc.  All Rights Reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Sun designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Sun in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 */

package sun.net.httpserver;

import java.util.*;

import java.nio.*;

import java.net.*;

import java.io.*;

import java.nio.channels.*;

import com.sun.net.httpserver.*;

import com.sun.net.httpserver.spi.*;

/**

 */

class Request {

    final static int BUF_LEN = 2048;

    final static byte CR = 13;

    final static byte LF = 10;

    private String startLine;

    private SocketChannel chan;

    private InputStream is;

    private OutputStream os;

    Request (InputStream rawInputStream, OutputStream rawout) throws IOException {

        this.chan = chan;

        is = rawInputStream;

        os = rawout;

        do {

            startLine = readLine();

            if (startLine == null) {

                return;

            }

            /* skip blank lines */

        } while (startLine == null ? false : startLine.equals (""));

    }

    char[] buf = new char [BUF_LEN];

    int pos;

    StringBuffer lineBuf;

    public InputStream inputStream () {

        return is;

    }

    public OutputStream outputStream () {

        return os;

    }

    /**

     * read a line from the stream returning as a String.

     * Not used for reading headers.

     */

    public String readLine () throws IOException {

        boolean gotCR = false, gotLF = false;

        pos = 0; lineBuf = new StringBuffer();

        while (!gotLF) {

            int c = is.read();

            if (c == -1) {

                return null;

            }

            if (gotCR) {

                if (c == LF) {

                    gotLF = true;

                } else {

                    gotCR = false;

                    consume (CR);

                    consume (c);

                }

            } else {

                if (c == CR) {

                    gotCR = true;

                } else {

                    consume (c);

                }

            }

        }

        lineBuf.append (buf, 0, pos);

        return new String (lineBuf);

    }

    private void consume (int c) {

        if (pos == BUF_LEN) {

            lineBuf.append (buf);

            pos = 0;

        }

        buf[pos++] = (char)c;

    }

    /**

     * returns the request line (first line of a request)

     */

    public String requestLine () {

        return startLine;

    }

    Headers hdrs = null;

    Headers headers () throws IOException {

        if (hdrs != null) {

            return hdrs;

        }

        hdrs = new Headers();

        char s[] = new char[10];

        int firstc = is.read();

        while (firstc != LF && firstc != CR && firstc >= 0) {

            int len = 0;

            int keyend = -1;

            int c;

            boolean inKey = firstc > ' ';

            s[len++] = (char) firstc;

    parseloop:{

                while ((c = is.read()) >= 0) {

                    switch (c) {

                      case ':':

                        if (inKey && len > 0)

                            keyend = len;

                        inKey = false;

                        break;

                      case '\t':

                        c = ' ';

                      case ' ':

                        inKey = false;

                        break;

                      case CR:

                      case LF:

                        firstc = is.read();

                        if (c == CR && firstc == LF) {

                            firstc = is.read();

                            if (firstc == CR)

                                firstc = is.read();

                        }

                        if (firstc == LF || firstc == CR || firstc > ' ')

                            break parseloop;

                        /* continuation */

                        c = ' ';

                        break;

                    }

                    if (len >= s.length) {

                        char ns[] = new char[s.length * 2];

                        System.arraycopy(s, 0, ns, 0, len);

                        s = ns;

                    }

                    s[len++] = (char) c;

                }

                firstc = -1;

            }

            while (len > 0 && s[len - 1] <= ' ')

                len--;

            String k;

            if (keyend <= 0) {

                k = null;

                keyend = 0;

            } else {

                k = String.copyValueOf(s, 0, keyend);

                if (keyend < len && s[keyend] == ':')

                    keyend++;

                while (keyend < len && s[keyend] <= ' ')

                    keyend++;

            }

            String v;

            if (keyend >= len)

                v = new String();

            else

                v = String.copyValueOf(s, keyend, len - keyend);

            hdrs.add (k,v);

        }

        return hdrs;

    }

    /**

     * Implements blocking reading semantics on top of a non-blocking channel

     */

    static class ReadStream extends InputStream {

        SocketChannel channel;

        SelectorCache sc;

        Selector selector;

        ByteBuffer chanbuf;

        SelectionKey key;

        int available;

        byte[] one;

        boolean closed = false, eof = false;

        ByteBuffer markBuf; /* reads may be satisifed from this buffer */

        boolean marked;

        boolean reset;

        int readlimit;

        static long readTimeout;

        ServerImpl server;

        static {

            readTimeout = ServerConfig.getReadTimeout();

        }

        public ReadStream (ServerImpl server, SocketChannel chan) throws IOException {

            this.channel = chan;

            this.server = server;

            sc = SelectorCache.getSelectorCache();

            selector = sc.getSelector();

            chanbuf = ByteBuffer.allocate (8* 1024);

            key = chan.register (selector, SelectionKey.OP_READ);

            available = 0;

            one = new byte[1];

            closed = marked = reset = false;

        }

        public synchronized int read (byte[] b) throws IOException {

            return read (b, 0, b.length);

        }

        public synchronized int read () throws IOException {

            int result = read (one, 0, 1);

            if (result == 1) {

                return one[0] & 0xFF;

            } else {

                return -1;

            }

        }

        public synchronized int read (byte[] b, int off, int srclen) throws IOException {

            int canreturn, willreturn;

            if (closed)

                throw new IOException ("Stream closed");

            if (eof) {

                return -1;

            }

            if (reset) { /* satisfy from markBuf */

                canreturn = markBuf.remaining ();

                willreturn = canreturn>srclen ? srclen : canreturn;

                markBuf.get(b, off, willreturn);

                if (canreturn == willreturn) {

                    reset = false;

                }

            } else { /* satisfy from channel */

                canreturn = available();

                while (canreturn == 0 && !eof) {

                    block ();

                    canreturn = available();

                }

                if (eof) {

                    return -1;

                }

                willreturn = canreturn>srclen ? srclen : canreturn;

                chanbuf.get(b, off, willreturn);

                available -= willreturn;

                if (marked) { /* copy into markBuf */

                    try {

                        markBuf.put (b, off, willreturn);

                    } catch (BufferOverflowException e) {

                        marked = false;

                    }

                }

            }

            return willreturn;

        }

        public synchronized int available () throws IOException {

            if (closed)

                throw new IOException ("Stream is closed");

            if (eof)

                return -1;

            if (reset)

                return markBuf.remaining();

            if (available > 0)

                return available;

            chanbuf.clear ();

            available = channel.read (chanbuf);

            if (available > 0) {

                chanbuf.flip();

            } else if (available == -1) {

                eof = true;

                available = 0;

            }

            return available;

        }

        /**

         * block() only called when available==0 and buf is empty

         */

        private synchronized void block () throws IOException {

            long currtime = server.getTime();

            long maxtime = currtime + readTimeout;

            while (currtime < maxtime) {

                if (selector.select (readTimeout) == 1) {

                    selector.selectedKeys().clear();

                    available ();

                    return;

                }

                currtime = server.getTime();

            }

            throw new SocketTimeoutException ("no data received");

        }

        public void close () throws IOException {

            if (closed) {

                return;

            }

            channel.close ();

            selector.selectNow();

            sc.freeSelector(selector);

            closed = true;

        }

        public synchronized void mark (int readlimit) {

            if (closed)

                return;

            this.readlimit = readlimit;

            markBuf = ByteBuffer.allocate (readlimit);

            marked = true;

            reset = false;

        }

        public synchronized void reset () throws IOException {

            if (closed )

                return;

            if (!marked)

                throw new IOException ("Stream not marked");

            marked = false;

            reset = true;

            markBuf.flip ();

        }

    }

    static class WriteStream extends java.io.OutputStream {

        SocketChannel channel;

        ByteBuffer buf;

        SelectionKey key;

        SelectorCache sc;

        Selector selector;

        boolean closed;

        byte[] one;

        ServerImpl server;

        static long writeTimeout;

        static {

            writeTimeout = ServerConfig.getWriteTimeout();

        }

        public WriteStream (ServerImpl server, SocketChannel channel) throws IOException {

            this.channel = channel;

            this.server = server;

            sc = SelectorCache.getSelectorCache();

            selector = sc.getSelector();

            key = channel.register (selector, SelectionKey.OP_WRITE);

            closed = false;

            one = new byte [1];

            buf = ByteBuffer.allocate (4096);

        }

        public synchronized void write (int b) throws IOException {

            one[0] = (byte)b;

            write (one, 0, 1);

        }

        public synchronized void write (byte[] b) throws IOException {

            write (b, 0, b.length);

        }

        public synchronized void write (byte[] b, int off, int len) throws IOException {

            int l = len;

            if (closed)

                throw new IOException ("stream is closed");

            int cap = buf.capacity();

            if (cap < len) {

                int diff = len - cap;

                buf = ByteBuffer.allocate (2*(cap+diff));

            }

            buf.clear();

            buf.put (b, off, len);

            buf.flip ();

            int n;

            while ((n = channel.write (buf)) < l) {

                l -= n;

                if (l == 0)

                    return;

                block();

            }

        }

        void block () throws IOException {

            long currtime = server.getTime();

            long maxtime = currtime + writeTimeout;

            while (currtime < maxtime) {

                if (selector.select (writeTimeout) == 1) {

                    selector.selectedKeys().clear ();

                    return;

                }

                currtime = server.getTime();

            }

            throw new SocketTimeoutException ("write blocked too long");

        }

        public void close () throws IOException {

            if (closed)

                return;

            channel.close ();

            selector.selectNow();

            sc.freeSelector(selector);

            closed = true;

        }

    }

}