/*
 * oauth2-oidc-sdk
 *
 * Copyright 2012-2016, Connect2id Ltd and contributors.
 *
 * 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.
 */

package com.nimbusds.oauth2.sdk.http;


import java.net.URI;
import java.net.URISyntaxException;
import java.util.Arrays;

import net.jcip.annotations.ThreadSafe;

import net.minidev.json.JSONArray;
import net.minidev.json.JSONObject;

import com.nimbusds.jwt.JWT;
import com.nimbusds.jwt.JWTParser;

import com.nimbusds.oauth2.sdk.ParseException;
import com.nimbusds.oauth2.sdk.util.JSONArrayUtils;
import com.nimbusds.oauth2.sdk.util.JSONObjectUtils;


/**
 * HTTP response with support for the parameters required to construct an 
 * {@link com.nimbusds.oauth2.sdk.Response OAuth 2.0 response message}.
 *
 * <p>Provided HTTP status code constants:
 *
 * <ul>
 *     <li>{@link #SC_OK HTTP 200 OK}
 *     <li>{@link #SC_CREATED HTTP 201 Created}
 *     <li>{@link #SC_FOUND HTTP 302 Redirect}
 *     <li>{@link #SC_BAD_REQUEST HTTP 400 Bad request}
 *     <li>{@link #SC_UNAUTHORIZED HTTP 401 Unauthorized}
 *     <li>{@link #SC_FORBIDDEN HTTP 403 Forbidden}
 *     <li>{@link #SC_SERVER_ERROR HTTP 500 Server error}
 * </ul>
 *
 * <p>Supported response headers:
 *
 * <ul>
 *     <li>Location
 *     <li>Content-Type
 *     <li>Cache-Control
 *     <li>Pragma
 *     <li>Www-Authenticate
 * </ul>
 */
@ThreadSafe
public class HTTPResponse extends HTTPMessage {

        
        /**
         * HTTP status code (200) indicating the request succeeded.
         */
        public static final int SC_OK = 200;


        /**
         * HTTP status code (201) indicating the request succeeded with a new
         * resource being created.
         */
        public static final int SC_CREATED = 201;
        
        
        /**
         * HTTP status code (302) indicating that the resource resides
         * temporarily under a different URI (redirect).
         */
        public static final int SC_FOUND = 302;
        
        
        /**
         * HTTP status code (400) indicating a bad request.
         */
        public static final int SC_BAD_REQUEST = 400;
        
        
        /**
         * HTTP status code (401) indicating that the request requires HTTP 
         * authentication.
         */
        public static final int SC_UNAUTHORIZED = 401;
        
        
        /**
         * HTTP status code (403) indicating that access to the resource was
         * forbidden.
         */
        public static final int SC_FORBIDDEN = 403;


        /**
         * HTTP status code (500) indicating an internal server error.
         */
        public static final int SC_SERVER_ERROR = 500;


        /**
         * HTTP status code (503) indicating the server is unavailable.
         */
        public static final int SC_SERVICE_UNAVAILABLE = 503;


        /**
         * The HTTP status code.
         */
        private final int statusCode;
        
        
        /**
         * The raw response content.
         */
        private String content = null;
        
        
        /**
         * Creates a new minimal HTTP response with the specified status code.
         *
         * @param statusCode The HTTP status code.
         */
        public HTTPResponse(final int statusCode) {
        
                this.statusCode = statusCode;
        }
        
        
        /**
         * Gets the HTTP status code.
         *
         * @return The HTTP status code.
         */
        public int getStatusCode() {
        
                return statusCode;
        }


        /**
         * Returns {@code true} if the HTTP status code indicates success
         * (2xx).
         *
         * @return {@code true} if the HTTP status code indicates success, else
         *         {@code false}.
         */
        public boolean indicatesSuccess() {

                return statusCode >= 200 && statusCode < 300;
        }
        
        
        /**
         * Ensures this HTTP response has the specified status code.
         *
         * @param expectedStatusCode The expected status code(s).
         *
         * @throws ParseException If the status code of this HTTP response 
         *                        doesn't match the expected.
         */ 
        public void ensureStatusCode(final int ... expectedStatusCode)
                throws ParseException {

                for (int c: expectedStatusCode) {

                        if (this.statusCode == c)
                                return;
                }

                throw new ParseException("Unexpected HTTP status code " + 
                        this.statusCode + 
                        ", must be " +  
                        Arrays.toString(expectedStatusCode));
        }


        /**
         * Ensures this HTTP response does not have a {@link #SC_OK 200 OK} 
         * status code.
         *
         * @throws ParseException If the status code of this HTTP response is
         *                        200 OK.
         */
        public void ensureStatusCodeNotOK()
                throws ParseException {

                if (statusCode == SC_OK)
                        throw new ParseException("Unexpected HTTP status code, must not be 200 (OK)");
        }
        
        
        /**
         * Gets the {@code Location} header value (for redirects).
         *
         * @return The header value, {@code null} if not specified.
         */
        public URI getLocation() {

                String value = getHeader("Location");

                if (value == null) {
                        return null;
                }

                try {
                        return new URI(value);

                } catch (URISyntaxException e) {
                        return null;
                }
        }
        
        
        /**
         * Sets the {@code Location} header value (for redirects).
         *
         * @param location The header value, {@code null} if not specified.
         */
        public void setLocation(final URI location) {
        
                setHeader("Location", location != null ? location.toString() : null);
        }
        
        
        /**
         * Gets the {@code Cache-Control} header value.
         *
         * @return The header value, {@code null} if not specified.
         */
        public String getCacheControl() {
        
                return getHeader("Cache-Control");
        }


        /**
         * Sets the {@code Cache-Control} header value.
         *
         * @param cacheControl The header value, {@code null} if not specified.
         */
        public void setCacheControl(final String cacheControl) {
        
                setHeader("Cache-Control", cacheControl);
        }
        
        
        /**
         * Gets the {@code Pragma} header value.
         *
         * @return The header value, {@code null} if not specified.
         */
        public String getPragma() {
        
                return getHeader("Pragma");
        }
        
        
        /**
         * Sets the {@code Pragma} header value.
         *
         * @param pragma The header value, {@code null} if not specified.
         */
        public void setPragma(final String pragma) {
        
                setHeader("Pragma", pragma);
        }
        
        
        /**
         * Gets the {@code WWW-Authenticate} header value.
         *
         * @return The header value, {@code null} if not specified.
         */
        public String getWWWAuthenticate() {
        
                return getHeader("WWW-Authenticate");
        }
        
        
        /**
         * Sets the {@code WWW-Authenticate} header value.
         *
         * @param wwwAuthenticate The header value, {@code null} if not 
         *                        specified.
         */
        public void setWWWAuthenticate(final String wwwAuthenticate) {
        
                setHeader("WWW-Authenticate", wwwAuthenticate);
        }
        
        
        /**
         * Ensures this HTTP response has a specified content body.
         *
         * @throws ParseException If the content body is missing or empty.
         */
        private void ensureContent()
                throws ParseException {
                
                if (content == null || content.isEmpty())
                        throw new ParseException("Missing or empty HTTP response body");
        }
        
        
        /**
         * Gets the raw response content.
         *
         * @return The raw response content, {@code null} if none.
         */
        public String getContent() {
        
                return content;
        }
        
        
        /**
         * Gets the response content as a JSON object.
         *
         * @return The response content as a JSON object.
         *
         * @throws ParseException If the Content-Type header isn't 
         *                        {@code application/json}, the response
         *                        content is {@code null}, empty or couldn't be
         *                        parsed to a valid JSON object.
         */
        public JSONObject getContentAsJSONObject()
                throws ParseException {
                
                ensureContentType(CommonContentTypes.APPLICATION_JSON);
                
                ensureContent();
                
                return JSONObjectUtils.parse(content);
        }


        /**
         * Gets the response content as a JSON array.
         *
         * @return The response content as a JSON array.
         *
         * @throws ParseException If the Content-Type header isn't
         *                        {@code application/json}, the response
         *                        content is {@code null}, empty or couldn't be
         *                        parsed to a valid JSON array.
         */
        public JSONArray getContentAsJSONArray()
                throws ParseException {

                ensureContentType(CommonContentTypes.APPLICATION_JSON);

                ensureContent();

                return JSONArrayUtils.parse(content);
        }
        
        
        /**
         * Gets the response content as a JSON Web Token (JWT).
         *
         * @return The response content as a JSON Web Token (JWT).
         *
         * @throws ParseException If the Content-Type header isn't
         *                        {@code application/jwt}, the response content 
         *                        is {@code null}, empty or couldn't be parsed
         *                        to a valid JSON Web Token (JWT).
         */
        public JWT getContentAsJWT()
                throws ParseException {
                
                ensureContentType(CommonContentTypes.APPLICATION_JWT);
                
                ensureContent();
                
                try {
                        return JWTParser.parse(content);
                        
                } catch (java.text.ParseException e) {
                
                        throw new ParseException(e.getMessage(), e);
                }
        }
        
        
        /**
         * Sets the raw response content.
         *
         * @param content The raw response content, {@code null} if none.
         */
        public void setContent(final String content) {
        
                this.content = content;
        }
}