/*
 *  Copyright (C) 2004-2020 Savoir-faire Linux Inc.
 *
 *  Author: Julien Bonjean <julien.bonjean@savoirfairelinux.com>
 *  Author: Guillaume Roguez <guillaume.roguez@savoirfairelinux.com>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  This program 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 for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA.
 */

#include <cstdio>
#include <cstring>
#include <cerrno>
#include <ctime>
#include <ciso646> // fix windows compiler bug

#include "client/ring_signal.h"

#ifdef _MSC_VER
#include <sys_time.h>
#else
#include <sys/time.h>
#endif

#include <string>
#include <sstream>
#include <iomanip>
#include <ios>
#include <mutex>
#include <thread>
#include <array>

#include "logger.h"

#ifdef __linux__
#include <syslog.h>
#include <unistd.h>
#include <sys/syscall.h>
#endif // __linux__

#ifdef __ANDROID__
#ifndef APP_NAME
#define APP_NAME "libdring"
#endif /* APP_NAME */
#endif

#define BLACK         "\033[22;30m"
#define GREEN         "\033[22;32m"
#define BROWN         "\033[22;33m"
#define BLUE          "\033[22;34m"
#define MAGENTA       "\033[22;35m"
#define GREY          "\033[22;37m"
#define DARK_GREY     "\033[01;30m"
#define LIGHT_RED     "\033[01;31m"
#define LIGHT_SCREEN  "\033[01;32m"
#define LIGHT_BLUE    "\033[01;34m"
#define LIGHT_MAGENTA "\033[01;35m"
#define LIGHT_CYAN    "\033[01;36m"
#define WHITE         "\033[01;37m"
#define END_COLOR     "\033[0m"

#ifndef _WIN32
#define RED    "\033[22;31m"
#define YELLOW "\033[01;33m"
#define CYAN   "\033[22;36m"
#else
#define FOREGROUND_WHITE 0x000f
#define RED              FOREGROUND_RED + 0x0008
#define YELLOW           FOREGROUND_RED + FOREGROUND_GREEN + 0x0008
#define CYAN             FOREGROUND_BLUE + FOREGROUND_GREEN + 0x0008
#define LIGHT_GREEN      FOREGROUND_GREEN + 0x0008
#endif // _WIN32

#define LOGFILE "dring"

#ifdef RING_UWP
static constexpr auto ENDL = "";
#else
static constexpr auto ENDL = "\n";
#endif

static int consoleLog;
static int debugMode;
static std::mutex logMutex;

// extract the last component of a pathname (extract a filename from its dirname)
static const char*
stripDirName(const char* path)
{
#ifdef _MSC_VER
    return strrchr(path, '\\') ? strrchr(path, '\\') + 1 : path;
#else
    return strrchr(path, '/') ? strrchr(path, '/') + 1 : path;
#endif
}

static std::string
contextHeader(const char* const file, int line)
{
#ifdef __linux__
    auto tid = syscall(__NR_gettid) & 0xffff;
#else
    auto tid = std::this_thread::get_id();
#endif // __linux__
    // Timestamp
    unsigned int secs, milli;
    struct timeval tv;

    if (!gettimeofday(&tv, NULL)) {
        secs = tv.tv_sec;
        milli = tv.tv_usec / 1000; // suppose that milli < 1000
    } else {
        secs = time(NULL);
        milli = 0;
    }

    std::ostringstream out;
    const auto prev_fill = out.fill();
    out << '[' << secs << '.' << std::right << std::setw(3) << std::setfill('0') << milli
        << std::left << '|' << std::right << std::setw(5) << std::setfill(' ') << tid << std::left;
    out.fill(prev_fill);

    // Context
    if (file) {
#ifdef RING_UWP
        constexpr auto width = 26;
#else
        constexpr auto width = 18;
#endif
        out << "|" << std::setw(width) << stripDirName(file) << ":" << std::setw(5)
            << std::setfill(' ') << line;
    }

    out << "] ";
    return out.str();
}

void
setConsoleLog(int c)
{
    if (c)
        ::closelog();
    else {
#ifdef _WIN32
        ::openlog(LOGFILE, WINLOG_PID, WINLOG_MAIL);
#else
        ::openlog(LOGFILE, LOG_NDELAY, LOG_USER);
#endif /* _WIN32 */
    }

    consoleLog = c;
}

void
setDebugMode(int d)
{
    debugMode = d;
}

int
getDebugMode(void)
{
    return debugMode;
}

static const char*
check_error(int result, char* buffer)
{
    switch (result) {
    case 0:
        return buffer;

    case ERANGE: /* should never happen */
        return "unknown (too big to display)";

    default:
        return "unknown (invalid error number)";
    }
}

static const char*
check_error(char* result, char*)
{
    return result;
}

void
strErr(void)
{
#ifdef __GLIBC__
    JAMI_ERR("%m");
#else
    char buf[1000];
    JAMI_ERR("%s", check_error(strerror_r(errno, buf, sizeof(buf)), buf));
#endif
}

namespace jami {

void
Logger::log(int level, const char* file, int line, bool linefeed, const char* const format, ...)
{
#if defined(TARGET_OS_IOS) && TARGET_OS_IOS
    if (!debugMode)
        return;
#endif
    if (!debugMode && level == LOG_DEBUG)
        return;

    va_list ap;
    va_start(ap, format);
#ifdef __ANDROID__
    __android_log_vprint(level, APP_NAME, format, ap);
#else
    Logger::vlog(level, file, line, linefeed, format, ap);
#endif
    va_end(ap);
}

void
Logger::vlog(
    const int level, const char* file, int line, bool linefeed, const char* format, va_list ap)
{
#if defined(TARGET_OS_IOS) && TARGET_OS_IOS
    if (!debugMode)
        return;
#endif
    if (!debugMode && level == LOG_DEBUG)
        return;

    // syslog is supposed to thread-safe, but not all implementations (Android?)
    // follow strictly POSIX rules... so we lock our mutex in any cases.
    std::lock_guard<std::mutex> lk {logMutex};

    if (consoleLog) {
#ifndef _WIN32
        const char* color_header = CYAN;
        const char* color_prefix = "";
#else
        WORD color_prefix = LIGHT_GREEN;
        WORD color_header = CYAN;
#endif
#if defined(_WIN32) && !defined(RING_UWP)
        HANDLE hConsole = GetStdHandle(STD_OUTPUT_HANDLE);
        CONSOLE_SCREEN_BUFFER_INFO consoleInfo;
        WORD saved_attributes;
#endif

        switch (level) {
        case LOG_ERR:
            color_prefix = RED;
            break;

        case LOG_WARNING:
            color_prefix = YELLOW;
            break;
        }

#ifndef _WIN32
        fputs(color_header, stderr);
#elif !defined(RING_UWP)
        GetConsoleScreenBufferInfo(hConsole, &consoleInfo);
        saved_attributes = consoleInfo.wAttributes;
        SetConsoleTextAttribute(hConsole, color_header);
#endif
        fputs(contextHeader(file, line).c_str(), stderr);
#ifdef _MSC_VER
        std::array<char, 4096> tmp;
        vsnprintf(tmp.data(), tmp.size(), format, ap);
        jami::emitSignal<DRing::DebugSignal::MessageSend>(contextHeader(file, line) + tmp.data());
#endif
#ifndef _WIN32
        fputs(END_COLOR, stderr);
        fputs(color_prefix, stderr);
#elif !defined(RING_UWP)
        SetConsoleTextAttribute(hConsole, saved_attributes);
        SetConsoleTextAttribute(hConsole, color_prefix);
#endif
        vfprintf(stderr, format, ap);

        if (linefeed)
            fputs(ENDL, stderr);

#ifndef _WIN32
        fputs(END_COLOR, stderr);
#elif !defined(RING_UWP)
        SetConsoleTextAttribute(hConsole, saved_attributes);
#endif
    } else {
        ::vsyslog(level, format, ap);
    }
}

} // namespace jami
