// Copyright (C) 2006 - 2008 Philip Aston
// All rights reserved.
//
// This file is part of The Grinder software distribution. Refer to
// the file LICENSE which is part of The Grinder distribution for
// licensing details. The Grinder distribution is available on the
// Internet at http://grinder.sourceforge.net/
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
// FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
// COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
// INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
// HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
// OF THE POSSIBILITY OF SUCH DAMAGE.

package net.grinder.util.http;


/**
 * Parse URI for interesting things, such as name-value pairs.
 *
 * @author Philip Aston
 */
public interface URIParser {

  /**
   * Parse a URI.
   *
   * @param uri
   *          The URI.
   * @param listener
   *          Callback interface.
   */
  void parse(String uri, ParseListener listener);

  /**
   * Callback interface for use with {@link URIParser#parse}.
   *
   * <p>
   * Methods are called with the maximum amount of text possible. This means
   * that {@link #fragment} will only be called once for a parse.
   * </p>
   *
   * <p>
   * All of the strings that are passed to the methods are unescaped.
   * </p>
   *
   * <p>
   * Each of the methods returns a <code>boolean</code>, which should be
   * interpreted as "continue parse". That is, if a method returns
   * <code>false</code> the parse is terminated.
   * </p>
   */
  interface ParseListener {

    /**
     * Called with the scheme for absolute URIs.
     *
     * @param scheme The scheme, without ':'.
     * @return See {ParseListener}.
     */
    boolean scheme(String scheme);

    /**
     * Called with the authority.
     *
     * @param authority The authority, without leading '//'.
     * @return See {ParseListener}.
     */
    boolean authority(String authority);

    /**
     * Called with path text. Called multiple times with everything in a path
     * (net_path, abs_path, rel_path from RFC 2396), except name-value tokens
     * found in path parameters.
     *
     * @param path
     *          The text. Includes any delimiting punctuation.
     * @return See {ParseListener}.
     */
    boolean path(String path);

    /**
     * Called with a name-value pair that was found in the path.
     *
     * @param name The name. URL decoded.
     * @param value The value. URL decoded.
     * @return See {ParseListener}.
     */
    boolean pathParameterNameValue(String name, String value);

    /**
     * Called with query string text.
     *
     * @param queryString
     *          The text. The leading '?' is stripped.
     * @return See {ParseListener}.
     */
    boolean queryString(String queryString);

    /**
     * Called with a name-value pair that was found in the query string.
     *
     * @param name The name. URL decoded.
     * @param value The value. URL decoded.
     * @return See {ParseListener}.
     */
    boolean queryStringNameValue(String name, String value);

    /**
     * Called with fragment.
     *
     * @param fragment The fragment. The leading '#' is stripped.
     * @return See {ParseListener}.
     */
    boolean fragment(String fragment);
  }

  /**
   * Null implementation of {@link URIParser.ParseListener}.
   */
  abstract class AbstractParseListener implements ParseListener {

    public boolean scheme(String scheme) {
      return true;
    }

    public boolean authority(String authority) {
      return true;
    }

    public boolean path(String path) {
      return true;
    }

    public boolean pathParameterNameValue(String name, String value) {
      return true;
    }

    public boolean queryString(String queryString) {
      return true;
    }

    public boolean queryStringNameValue(String name, String value) {
      return true;
    }

    public boolean fragment(String fragment) {
      return true;
    }

  }
}