/*******************************************************************************
 * ============LICENSE_START==================================================
 * * org.onap.dmaap
 * * ===========================================================================
 * * Copyright © 2017 AT&T Intellectual Property. All rights reserved.
 * * ===========================================================================
 * * Licensed 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.
 * * ============LICENSE_END====================================================
 * *
 * * ECOMP is a trademark and service mark of AT&T Intellectual Property.
 * *
 ******************************************************************************/
package org.json;



import java.util.Iterator;


public class HTTP {

    /** Carriage return/line feed. */
    public static final String CRLF = "\r\n";

    /**
     * Convert an HTTP header string into a JSONObject. It can be a request
     * header or a response header. A request header will contain
     * <pre>{
     *    Method: "POST" (for example),
     *    "Request-URI": "/" (for example),
     *    "HTTP-Version": "HTTP/1.1" (for example)
     * }</pre>
     * A response header will contain
     * <pre>{
     *    "HTTP-Version": "HTTP/1.1" (for example),
     *    "Status-Code": "200" (for example),
     *    "Reason-Phrase": "OK" (for example)
     * }</pre>
     * In addition, the other parameters in the header will be captured, using
     * the HTTP field names as JSON names, so that <pre>
     *    Date: Sun, 26 May 2002 18:06:04 GMT
     *    Cookie: Q=q2=PPEAsg--; B=677gi6ouf29bn&b=2&f=s
     *    Cache-Control: no-cache</pre>
     * become
     * <pre>{...
     *    Date: "Sun, 26 May 2002 18:06:04 GMT",
     *    Cookie: "Q=q2=PPEAsg--; B=677gi6ouf29bn&b=2&f=s",
     *    "Cache-Control": "no-cache",
     * ...}</pre>
     * It does no further checking or conversion. It does not parse dates.
     * It does not do '%' transforms on URLs.
     * @param string An HTTP header string.
     * @return A JSONObject containing the elements and attributes
     * of the XML string.
     * @throws JSONException
     */
    public static JSONObject toJSONObject(String string) throws JSONException {
        JSONObject     jo = new JSONObject();
        HTTPTokener    x = new HTTPTokener(string);
        String         token;

        token = x.nextToken();
        if (token.toUpperCase().startsWith("HTTP")) {

// Response

            jo.put("HTTP-Version", token);
            jo.put("Status-Code", x.nextToken());
            jo.put("Reason-Phrase", x.nextTo('\0'));
            x.next();

        } else {

// Request

            jo.put("Method", token);
            jo.put("Request-URI", x.nextToken());
            jo.put("HTTP-Version", x.nextToken());
        }

// Fields

        while (x.more()) {
            String name = x.nextTo(':');
            x.next(':');
            jo.put(name, x.nextTo('\0'));
            x.next();
        }
        return jo;
    }


    /**
     * Convert a JSONObject into an HTTP header. A request header must contain
     * <pre>{
     *    Method: "POST" (for example),
     *    "Request-URI": "/" (for example),
     *    "HTTP-Version": "HTTP/1.1" (for example)
     * }</pre>
     * A response header must contain
     * <pre>{
     *    "HTTP-Version": "HTTP/1.1" (for example),
     *    "Status-Code": "200" (for example),
     *    "Reason-Phrase": "OK" (for example)
     * }</pre>
     * Any other members of the JSONObject will be output as HTTP fields.
     * The result will end with two CRLF pairs.
     * @param jo A JSONObject
     * @return An HTTP header string.
     * @throws JSONException if the object does not contain enough
     *  information.
     */
    public static String toString(JSONObject jo) throws JSONException {
        Iterator<String> keys = jo.keys();
        String       string;
        StringBuffer sb = new StringBuffer();
        if (jo.has("Status-Code") && jo.has("Reason-Phrase")) {
            sb.append(jo.getString("HTTP-Version"));
            sb.append(' ');
            sb.append(jo.getString("Status-Code"));
            sb.append(' ');
            sb.append(jo.getString("Reason-Phrase"));
        } else if (jo.has("Method") && jo.has("Request-URI")) {
            sb.append(jo.getString("Method"));
            sb.append(' ');
            sb.append('"');
            sb.append(jo.getString("Request-URI"));
            sb.append('"');
            sb.append(' ');
            sb.append(jo.getString("HTTP-Version"));
        } else {
            throw new JSONException("Not enough material for an HTTP header.");
        }
        sb.append(CRLF);
        while (keys.hasNext()) {
            string = keys.next().toString();
            if (!"HTTP-Version".equals(string)      && !"Status-Code".equals(string) &&
                    !"Reason-Phrase".equals(string) && !"Method".equals(string) &&
                    !"Request-URI".equals(string)   && !jo.isNull(string)) {
                sb.append(string);
                sb.append(": ");
                sb.append(jo.getString(string));
                sb.append(CRLF);
            }
        }
        sb.append(CRLF);
        return sb.toString();
    }
}