/*

 * Copyright (c) 2015, Oracle and/or its affiliates. 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.

 *

 * 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.io.IOException;

import java.net.BindException;

import java.util.ArrayList;

import java.util.Arrays;

import java.util.List;

import java.util.Properties;

import java.util.concurrent.atomic.AtomicBoolean;

import java.util.function.Consumer;

import java.util.regex.Pattern;

import java.util.stream.Collectors;

import sun.management.Agent;

import sun.management.AgentConfigurationError;

import jdk.testlibrary.JDKToolLauncher;

import jdk.testlibrary.ProcessTools;

/**

 * A helper class for issuing ManagementAgent.* diagnostic commands and capturing

 * their output.

 */

final class ManagementAgentJcmd {

    private static final String CMD_STOP = "ManagementAgent.stop";

    private static final String CMD_START = "ManagementAgent.start";

    private static final String CMD_START_LOCAL = "ManagementAgent.start_local";

    private static final String CMD_STATUS = "ManagementAgent.status";

    private static final String CMD_PRINTPERF = "PerfCounter.print";

    private final String id;

    private final boolean verbose;

    public ManagementAgentJcmd(String targetApp, boolean verbose) {

        this.id = targetApp;

        this.verbose = verbose;

    }

    /**

     * `jcmd`

     * @return The JCMD output

     * @throws IOException

     * @throws InterruptedException

     */

    public String list() throws IOException, InterruptedException {

        return jcmd();

    }

    /**

     * `jcmd PerfCounter.print`

     * @return Returns the available performance counters with their values as

     *         {@linkplain Properties} instance

     * @throws IOException

     * @throws InterruptedException

     */

    public Properties perfCounters() throws IOException, InterruptedException {

        return perfCounters(".*");

    }

    /**

     * `jcmd PerfCounter.print | grep {exp}>`

     * @param regex Regular expression for including perf counters in the result

     * @return Returns the matching performance counters with their values

     *         as {@linkplain Properties} instance

     * @throws IOException

     * @throws InterruptedException

     */

    public Properties perfCounters(String regex) throws IOException, InterruptedException {

        Pattern pat = Pattern.compile(regex);

        Properties p = new Properties();

        for(String l : jcmd(CMD_PRINTPERF).split("\\n")) {

            String[] kv = l.split("=");

            if (kv.length > 1) {

                if (pat.matcher(kv[0]).matches()) {

                    p.setProperty(kv[0], kv[1].replace("\"", ""));

                }

            }

        }

        return p;

    }

    /**

     * `jcmd <app> ManagementAgent.stop`

     * @return The JCMD output

     * @throws IOException

     * @throws InterruptedException

     */

    public String stop() throws IOException, InterruptedException {

        return jcmd(CMD_STOP);

    }

    /**

     * `jcmd <app> ManagementAgent.start_local`

     * @return The JCMD output

     * @throws IOException

     * @throws InterruptedException

     */

    public String startLocal() throws IOException, InterruptedException {

        return jcmd(CMD_START_LOCAL);

    }

    /**

     * `jcmd <app> ManagementAgent.start <args>`

     * @return The JCMD output

     * @param params The arguments to <b>ManagementAgent.start</b> command

     * @throws IOException

     * @throws InterruptedException

     */

    public String start(String ... params) throws IOException, InterruptedException {

        return start(c->{}, params);

    }

    /**

     * `jcmd <pp> ManagementAgent.start <args>`

     * @param c A string consumer used to inspect the jcmd output line-by-line

     * @param params The arguments to <b>ManagementAgent.start</b> command

     * @return The JCMD output

     * @throws IOException

     * @throws InterruptedException

     */

    public String start(Consumer<String> c, String ... params) throws IOException, InterruptedException {

        List<String> args = new ArrayList<>();

        args.add(CMD_START);

        args.addAll(Arrays.asList(params));

        return jcmd(c, args.toArray(new String[args.size()]));

    }

    public String status() throws IOException, InterruptedException {

        return jcmd(CMD_STATUS);

    }

    /**

     * Run the "jcmd" command

     *

     * @param command Command + arguments

     * @return The JCMD output

     * @throws IOException

     * @throws InterruptedException

     */

    private String jcmd(String ... command) throws IOException, InterruptedException {

        if (command.length == 0) {

            return jcmd(null, c->{});

        } else {

            return jcmd(c->{}, command);

        }

    }

    /**

     * Run the "jcmd" command

     *

     * @param c {@linkplain Consumer} instance

     * @param command Command + arguments

     * @return The JCMD output

     * @throws IOException

     * @throws InterruptedException

     */

    private String jcmd(Consumer<String> c, String ... command) throws IOException, InterruptedException {

        return jcmd(id, c, command);

    }

    /**

     * Run the "jcmd" command

     *

     * @param target The target application name (or PID)

     * @param c {@linkplain Consumer} instance

     * @param command Command + arguments

     * @return The JCMD output

     * @throws IOException

     * @throws InterruptedException

     */

    private String jcmd(String target, final Consumer<String> c, String ... command) throws IOException, InterruptedException {

        dbg_print("[jcmd] " + (command.length > 0 ? command[0] : "list"));

        JDKToolLauncher l = JDKToolLauncher.createUsingTestJDK("jcmd");

        l.addToolArg(target);

        for (String cmd : command) {

            l.addToolArg(cmd);

        }

        AtomicBoolean portUnavailable = new AtomicBoolean(false);

        Process p = ProcessTools.startProcess(

            "jcmd",

            new ProcessBuilder(l.getCommand()),

            line -> {

                if (line.contains("BindException") ||

                    line.contains(Agent.getText(AgentConfigurationError.CONNECTOR_SERVER_IO_ERROR))) {

                    portUnavailable.set(true);

                } else {

                    output.append(line).append('\n');

                    c.accept(line);

                }

            }

        );

        p.waitFor();

        dbg_print("[jcmd] --------");

        if (portUnavailable.get()) {

            String cmd = Arrays.asList(l.getCommand()).stream()

                    .collect(

                            Collectors.joining(" ", "", ": Unable to bind address")

                    );

            throw new BindException(cmd);

        }

        return output.toString();

    }

    private void dbg_print(String msg) {

        if (verbose) {

            System.out.println("DBG: " + msg);

        }

    }

}