/*

 * 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.  Oracle designates this

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

 * by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

import java.util.ArrayList;

import java.util.List;

import java.util.Locale;

import java.util.Map;

import java.util.Set;

import java.util.function.Supplier;

import javax.net.ssl.SNIServerName;

import javax.net.ssl.SSLParameters;

/**

 * -Djava.net.HttpClient.log=

 *          errors,requests,headers,

 *          frames[:control:data:window:all..],content,ssl,trace

 *

 * Any of errors, requests, headers or content are optional.

 *

 * Other handlers may be added. All logging is at level INFO

 *

 * Logger name is "jdk.httpclient.HttpClient"

 */

// implements System.Logger in order to be skipped when printing the caller's

// information

public abstract class Log implements System.Logger {

    static final String logProp = "jdk.httpclient.HttpClient.log";

    public static final int OFF = 0;

    public static final int ERRORS = 0x1;

    public static final int REQUESTS = 0x2;

    public static final int HEADERS = 0x4;

    public static final int CONTENT = 0x8;

    public static final int FRAMES = 0x10;

    public static final int SSL = 0x20;

    public static final int TRACE = 0x40;

    static int logging;

    // Frame types: "control", "data", "window", "all"

    public static final int CONTROL = 1; // all except DATA and WINDOW_UPDATES

    public static final int DATA = 2;

    public static final int WINDOW_UPDATES = 4;

    public static final int ALL = CONTROL| DATA | WINDOW_UPDATES;

    static int frametypes;

    static final System.Logger logger;

    static {

        String s = Utils.getNetProperty(logProp);

        if (s == null) {

            logging = OFF;

        } else {

            String[] vals = s.split(",");

            for (String val : vals) {

                switch (val.toLowerCase(Locale.US)) {

                    case "errors":

                        logging |= ERRORS;

                        break;

                    case "requests":

                        logging |= REQUESTS;

                        break;

                    case "headers":

                        logging |= HEADERS;

                        break;

                    case "content":

                        logging |= CONTENT;

                        break;

                    case "ssl":

                        logging |= SSL;

                        break;

                    case "trace":

                        logging |= TRACE;

                        break;

                    case "all":

                        logging |= CONTENT|HEADERS|REQUESTS|FRAMES|ERRORS|TRACE|SSL;

                        break;

                }

                if (val.startsWith("frames")) {

                    logging |= FRAMES;

                    String[] types = val.split(":");

                    if (types.length == 1) {

                        frametypes = CONTROL | DATA | WINDOW_UPDATES;

                    } else {

                        for (String type : types) {

                                case "control":

                                    frametypes |= CONTROL;

                                    break;

                                case "data":

                                    frametypes |= DATA;

                                    break;

                                case "window":

                                    frametypes |= WINDOW_UPDATES;

                                    break;

                                case "all":

                                    frametypes = ALL;

                                    break;

                            }

                        }

                    }

                }

            }

        }

        if (logging != OFF) {

            logger = System.getLogger("jdk.httpclient.HttpClient");

        } else {

            logger = null;

        }

    }

    public static boolean errors() {

        return (logging & ERRORS) != 0;

    }

    public static boolean requests() {

        return (logging & REQUESTS) != 0;

    }

    public static boolean headers() {

        return (logging & HEADERS) != 0;

    }

    public static boolean trace() {

        return (logging & TRACE) != 0;

    }

    public static boolean ssl() {

        return (logging & SSL) != 0;

    }

    public static boolean frames() {

        return (logging & FRAMES) != 0;

    }

    public static void logError(String s, Object... s1) {

        if (errors()) {

            logger.log(Level.INFO, "ERROR: " + s, s1);

        }

    }

    public static void logError(Throwable t) {

        if (errors()) {

            String s = Utils.stackTrace(t);

            logger.log(Level.INFO, "ERROR: " + s);

        }

    }

    public static void logSSL(String s, Object... s1) {

        if (ssl()) {

            logger.log(Level.INFO, "SSL: " + s, s1);

        }

    }

    public static void logSSL(Supplier<String> msgSupplier) {

        if (ssl()) {

            logger.log(Level.INFO, "SSL: " + msgSupplier.get());

        }

    }

    public static void logTrace(String s, Object... s1) {

        if (trace()) {

            String format = "TRACE: " + s;

            logger.log(Level.INFO, format, s1);

        }

    }

    public static void logRequest(String s, Object... s1) {

        if (requests()) {

            logger.log(Level.INFO, "REQUEST: " + s, s1);

        }

    }

    public static void logResponse(Supplier<String> supplier) {

        if (requests()) {

            logger.log(Level.INFO, "RESPONSE: " + supplier.get());

        }

    }

    public static void logHeaders(String s, Object... s1) {

        if (headers()) {

            logger.log(Level.INFO, "HEADERS: " + s, s1);

        }

    }

    public static boolean loggingFrame(Class<? extends Http2Frame> clazz) {

        if (frametypes == ALL) {

            return true;

        }

        if (clazz == DataFrame.class) {

            return (frametypes & DATA) != 0;

        } else if (clazz == WindowUpdateFrame.class) {

            return (frametypes & WINDOW_UPDATES) != 0;

        } else {

            return (frametypes & CONTROL) != 0;

        }

    }

    public static void logFrames(Http2Frame f, String direction) {

        if (frames() && loggingFrame(f.getClass())) {

            logger.log(Level.INFO, "FRAME: " + direction + ": " + f.toString());

        }

    }

    public static void logParams(SSLParameters p) {

        if (!Log.ssl()) {

            return;

        }

        if (p == null) {

            Log.logSSL("SSLParameters: Null params");

            return;

        }

        final StringBuilder sb = new StringBuilder("SSLParameters:");

        final List<Object> params = new ArrayList<>();

        if (p.getCipherSuites() != null) {

            for (String cipher : p.getCipherSuites()) {

                sb.append("\n    cipher: {")

                        .append(params.size()).append("}");

                params.add(cipher);

            }

        }

        // SSLParameters.getApplicationProtocols() can't return null

        // JDK 8 EXCL START

        for (String approto : p.getApplicationProtocols()) {

            sb.append("\n    application protocol: {")

                    .append(params.size()).append("}");

            params.add(approto);

        }

        // JDK 8 EXCL END

        if (p.getProtocols() != null) {

            for (String protocol : p.getProtocols()) {

                sb.append("\n    protocol: {")

                        .append(params.size()).append("}");

                params.add(protocol);

            }

        }

        if (p.getServerNames() != null) {

            for (SNIServerName sname : p.getServerNames()) {

                sb.append("\n    server name: {")

                        .append(params.size()).append("}");

                params.add(sname.toString());

            }

        }

        sb.append('\n');

        Log.logSSL(sb.toString(), params.toArray());

    }

    public static void dumpHeaders(StringBuilder sb, String prefix, HttpHeaders headers) {

        if (headers != null) {

            Map<String,List<String>> h = headers.map();

            Set<Map.Entry<String,List<String>>> entries = h.entrySet();

            for (Map.Entry<String,List<String>> entry : entries) {

                String key = entry.getKey();

                List<String> values = entry.getValue();

                for (String value : values) {

                    sb.append(' ').append(value);

                }

            }

        }

    }

    // not instantiable

    private Log() {}

}