/*
 * Copyright (c) 2017-2019 Cisco and/or its affiliates.
 * 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.
 */

#ifndef _WIN32
#include <unistd.h>
#endif
#include <errno.h>
#include <fcntl.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>

#include <hicn/hicn-light/config.h>
#include <hicn/core/forwarder.h>
#include <hicn/util/log.h>
#include <hicn/base/loop.h>

static void _printRed(const char *output) {
#ifndef _WIN32
    printf("\033[0;31m%s", output);
#else
    HANDLE hConsole = NULL;
    WORD currentConsoleAttr;
    CONSOLE_SCREEN_BUFFER_INFO csbi;
    hConsole = GetStdHandle(STD_OUTPUT_HANDLE);
    if (GetConsoleScreenBufferInfo(hConsole, &csbi))
        currentConsoleAttr = csbi.wAttributes;
    SetConsoleTextAttribute(hConsole, 4);
    printf("%s", output);
    SetConsoleTextAttribute(hConsole, currentConsoleAttr);
#endif
}

static void _printWhite(const char *output) {
#ifndef _WIN32
    printf("\033[0m%s", output);
#else
    HANDLE hConsole = NULL;
    WORD currentConsoleAttr;
    CONSOLE_SCREEN_BUFFER_INFO csbi;
    hConsole = GetStdHandle(STD_OUTPUT_HANDLE);
    if (GetConsoleScreenBufferInfo(hConsole, &csbi))
        currentConsoleAttr = csbi.wAttributes;
    SetConsoleTextAttribute(hConsole, 7);
    printf("%s", output);
    SetConsoleTextAttribute(hConsole, currentConsoleAttr);
#endif
}

static void _displayForwarderLogo(void) {
    _printRed("   ____ ___      _       ");
    _printWhite("  __    _               __ _        __   __\n");
    _printRed("  / __// _ \\    (_)___  ");
    _printWhite("  / /   (_)____ ___ ____/ /(_)___ _ / /  / /_\n");
    _printRed(" / _/ / // /_  / // _ \\ ");
    _printWhite(" / _ \\ / // __// _ \\___/ // // _ `// _ \\/ __/\n");
    _printRed("/_/  /____/(_)/_/ \\___/ ");
    _printWhite("/_//_//_/ \\__//_//_/  /_//_/ \\_, //_//_/\\__/\n");
    _printWhite(
            "                                                    /___/            "
            "\n");
    printf("\n");
}

static void _usage(int exitCode) {
#ifndef _WIN32
    printf(
            "Usage: hicn-light-daemon [--port port] [--capacity objectStoreSize] "
            "[--log facility=level] [--log-file filename] [--config file]\n");
#else
    printf(
            "Usage: hicn-light-daemon.exe [--port port] [--daemon] [--capacity objectStoreSize] "
            "[--log facility=level] [--log-file filename] [--config file]\n");
#endif
    printf("\n");
    printf(
            "hicn-light run as a daemon is the program to launch the forwarder, "
            "either as a console program\n");
    printf(
            "or a background daemon (detatched from console).  Once running, use the "
            "program controller to\n");
    printf("configure hicn-light.\n");
    printf("\n");
    printf(
            "The configuration file contains configuration lines as per "
            "controller\n");
    printf(
            "If logging level or content store capacity is set in the configuraiton "
            "file, it overrides the command_line\n");
    printf(
            "When a configuration file is specified, no default listeners on 'port' "
            "are setup.  Only 'add listener' lines\n");
    printf("in the configuration file matter.\n");
    printf("\n");
    printf(
            "If no configuration file is specified, daemon will listen on TCP and "
            "UDP ports specified by\n");
    printf(
            "the --port flag (or default port).  It will listen on both IPv4 and "
            "IPv6 if available.\n");
    printf("\n");
    printf("Options:\n");
    printf("--port            = tcp port for in-bound connections\n");
#ifndef _WIN32
    printf("--daemon          = start as daemon process\n");
#endif
    printf("--objectStoreSize = maximum number of content objects to cache\n");
    printf(
            "--log             = sets a facility to a given log level.  You can have "
            "multiple of these.\n");
    printf(
            "                    facilities: all, config, core, io, message, "
            "processor\n");
    printf(
            "                    levels: debug, info, notice, warning, error, "
            "critical, alert, off\n");
    printf("                    example: daemon --log io=debug --log core=off\n");
    printf(
            "--log-file        = file to write log messages to (required in daemon "
            "mode)\n");
    printf("--config           = configuration filename\n");
    printf("\n");
    exit(exitCode);
}

#if 0
static void _setLogLevelToLevel(int logLevelArray[LoggerFacility_END],
        LoggerFacility facility,
        const char *levelString) {
    PARCLogLevel level = parcLogLevel_FromString(levelString);

    if (level < PARCLogLevel_All) {
        // we have a good facility and level
        logLevelArray[facility] = level;
    } else {
        printf("Invalid log level string %s\n", levelString);
        _usage(EXIT_FAILURE);
    }
}

/**
 * string: "facility=level"
 * Set the right thing in the logger
 */
static void _setLogLevel(int logLevelArray[LoggerFacility_END],
        const char *string) {
    char *tofree = parcMemory_StringDuplicate(string, strlen(string));
    char *p = tofree;

    char *facilityString = strtok(p, "=");
    if (facilityString) {
        char *levelString = strtok(NULL, "=");

        if (strcasecmp(facilityString, "all") == 0) {
            for (LoggerFacility facility = 0; facility < LoggerFacility_END;
                    facility++) {
                _setLogLevelToLevel(logLevelArray, facility, levelString);
            }
        } else {
            LoggerFacility facility;
            for (facility = 0; facility < LoggerFacility_END; facility++) {
                if (strcasecmp(facilityString, logger_FacilityString(facility)) == 0) {
                    break;
                }
            }

            if (facility < LoggerFacility_END) {
                _setLogLevelToLevel(logLevelArray, facility, levelString);
            } else {
                printf("Invalid facility string %s\n", facilityString);
                _usage(EXIT_FAILURE);
            }
        }
    }

    parcMemory_Deallocate((void **)&tofree);
}
#endif

#ifndef _WIN32
static void _daemonize(void) {
    if (getppid() == 1) {
        // already a daemon
        return;
    }

    int forkReturn = fork();
    assert(forkReturn >= 0);

    if (forkReturn > 0) {
        // parent exits
        exit(EXIT_SUCCESS);
    }

    // Child daemon detaches
    printf("child continuing, pid = %u\n", getpid());

    // get a new process group independent from old parent
    setsid();

    /* close all descriptors */
#ifdef __ANDROID__
    for (int i = sysconf(_SC_OPEN_MAX); i >= 0; --i) {
        close(i);
    }
#else
    for (int i = getdtablesize(); i >= 0; --i) {
        close(i);
    }
#endif
    // reset errno because it might be seg to EBADF from the close calls above
    errno = 0;

    // Redirect stdin and stdout and stderr to /dev/null
    const char *devnull = "/dev/null";
    int nullfile = open(devnull, O_RDWR);
    assert(nullfile >= 0);

    int ret;
    ret = dup(nullfile);
    assert(ret == 1);
    ret = dup(nullfile);
    assert(ret == 2);
    (void)ret; /* UNUSED */

    // forwarder will capture signals
}
#endif

#if 0
static Logger *_createLogfile(const char *logfile) {
#ifndef _WIN32
    int logfd = open(logfile, O_WRONLY | O_APPEND | O_CREAT, S_IWUSR | S_IRUSR);
#else
    int logfd =
        _open(logfile, _O_WRONLY | _O_APPEND | _O_CREAT, _S_IWRITE | _S_IREAD);
#endif
    if (logfd < 0) {
        fprintf(stderr, "Error opening %s for writing: (%d) %s\n", logfile, errno,
                strerror(errno));
        exit(EXIT_FAILURE);
    }

#ifndef _WIN32
    chmod(logfile, S_IRWXU);
#endif

    PARCFileOutputStream *fos = parcFileOutputStream_Create(logfd);
    PARCOutputStream *pos = parcFileOutputStream_AsOutputStream(fos);
    PARCLogReporter *reporter = parcLogReporterFile_Create(pos);

    Logger *logger = logger_Create(reporter, parcClock_Wallclock());

    parcOutputStream_Release(&pos);
    parcLogReporter_Release(&reporter);

    return logger;
}
#endif

int main(int argc, const char *argv[]) {
    _displayForwarderLogo();
#ifndef _WIN32
    bool daemon = false;
#else
    WSADATA wsaData = {0};
    WSAStartup(MAKEWORD(2, 2), &wsaData);
#endif

    uint16_t port = PORT_NUMBER;
    uint16_t configurationPort = 2001;
    int capacity = -1;
    const char *configFileName = NULL;

    char *logfile = NULL;

    if (argc == 2 && strcasecmp(argv[1], "-h") == 0) {
        _usage(EXIT_SUCCESS);
    }

#if 0
    int logLevelArray[LoggerFacility_END];
    for (int i = 0; i < LoggerFacility_END; i++) {
        logLevelArray[i] = -1;
    }
#endif

    for (int i = 0; i < argc; i++) {
        if (argv[i][0] == '-') {
            if (strcmp(argv[i], "--config") == 0) {
                configFileName = argv[i + 1];
                i++;
            } else if (strcmp(argv[i], "--port") == 0) {
                port = atoi(argv[i + 1]);
                i++;
#ifndef _WIN32
            } else if (strcmp(argv[i], "--daemon") == 0) {
                daemon = true;
#endif
            } else if (strcmp(argv[i], "--capacity") == 0 ||
                    strcmp(argv[i], "-c") == 0) {
                capacity = atoi(argv[i + 1]);
                i++;
#if 0
            } else if (strcmp(argv[i], "--log") == 0) {
                _setLogLevel(logLevelArray, argv[i + 1]);
                i++;
            } else if (strcmp(argv[i], "--log-file") == 0) {
                if (logfile) {
                    // error cannot repeat
                    fprintf(stderr, "Cannot specify --log-file more than once\n");
                    _usage(EXIT_FAILURE);
                }

                logfile = parcMemory_StringDuplicate(argv[i + 1], strlen(argv[i + 1]));
                i++;
#endif
            } else {
                _usage(EXIT_FAILURE);
            }
        }
    }

    // set restrictive umask, in case we create any files
    umask(027);

#ifndef _WIN32
    if (daemon && (logfile == NULL)) {
        fprintf(stderr, "Must specify a logfile when running in daemon mode\n");
        _usage(EXIT_FAILURE);
    }

    if (daemon) {
        // inside this call, parent will EXIT_SUCCESS and child will continue
        _daemonize();
    }
#endif

#if 0
    Logger *logger = NULL;
    if (logfile) {
        logger = _createLogfile(logfile);
        parcMemory_Deallocate((void **)&logfile);
    } else {
        PARCLogReporter *stdoutReporter = parcLogReporterTextStdout_Create();
        logger = logger_Create(stdoutReporter, parcClock_Wallclock());
        parcLogReporter_Release(&stdoutReporter);
    }

    for (int i = 0; i < LoggerFacility_END; i++) {
        if (logLevelArray[i] > -1) {
            logger_SetLogLevel(logger, i, logLevelArray[i]);
        }
    }
#endif

    /*
     * The loop should be created before the forwarder instance as it is needed
     * for timers
     */
    MAIN_LOOP = loop_create();

    forwarder_t * forwarder = forwarder_create();
    if (!forwarder) {
        ERROR("Forwarder initialization failed. Are you running it with sudo privileges?");
        return -1;
    }

    configuration_t * configuration = forwarder_get_configuration(forwarder);
    if (capacity > -1) {
        configuration_cs_set_size(configuration, capacity);
    }

    forwarder_setup_local_listeners(forwarder, port);
    if (configFileName) {
        forwarder_read_config(forwarder, configFileName);
    }

    INFO("hicn-light running port %d configuration-port %d", port,
            configurationPort);

    /* Main loop */
    if (loop_dispatch(MAIN_LOOP) < 0) {
        ERROR("Failed to run main loop");
        return EXIT_FAILURE;
    }

    INFO("hicn-light exiting port %d", port);

    if (loop_undispatch(MAIN_LOOP) < 0) {
        ERROR("Failed to terminate main loop");
        return EXIT_FAILURE;
    }

    forwarder_free(forwarder);

    loop_free(MAIN_LOOP);
    MAIN_LOOP = NULL;

#ifndef _WIN32
    sleep(2);
#else
    Sleep(2000);
    WSACleanup();
#endif

    return 0;
}