rang.hpp

/*
This is free and unencumbered software released into the public domain.

Anyone is free to copy, modify, publish, use, compile, sell, or
distribute this software, either in source code form or as a compiled
binary, for any purpose, commercial or non-commercial, and by any
means.

In jurisdictions that recognize copyright laws, the author or authors
of this software dedicate any and all copyright interest in the
software to the public domain. We make this dedication for the benefit
of the public at large and to the detriment of our heirs and
successors. We intend this dedication to be an overt act of
relinquishment in perpetuity of all present and future rights to this
software under copyright law.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
OTHER DEALINGS IN THE SOFTWARE.

For more information, please refer to <http://unlicense.org>
*/
#ifndef RANG_DOT_HPP
#define RANG_DOT_HPP

#if defined(__unix__) || defined(__unix) || defined(__linux__)
#define OS_LINUX
#elif defined(WIN32) || defined(_WIN32) || defined(_WIN64)
#define OS_WIN
#elif defined(__APPLE__) || defined(__MACH__)
#define OS_MAC
#else
#error Unknown Platform
#endif

#if defined(OS_LINUX) || defined(OS_MAC)
#include <unistd.h>

#elif defined(OS_WIN)

#if defined(_WIN32_WINNT) && (_WIN32_WINNT < 0x0600)
#error                                                                         \
  "Please include rang.hpp before any windows system headers or set _WIN32_WINNT at least to _WIN32_WINNT_VISTA"
#elif !defined(_WIN32_WINNT)
#define _WIN32_WINNT _WIN32_WINNT_VISTA
#endif

#include <windows.h>
#include <io.h>
#include <memory>

// Only defined in windows 10 onwards, redefining in lower windows since it
// doesn't gets used in lower versions
// https://docs.microsoft.com/en-us/windows/console/getconsolemode
#ifndef ENABLE_VIRTUAL_TERMINAL_PROCESSING
#define ENABLE_VIRTUAL_TERMINAL_PROCESSING 0x0004
#endif

#endif

#include <algorithm>
#include <atomic>
#include <cstdlib>
#include <cstring>
#include <iostream>

namespace rang {

/* For better compability with most of terminals do not use any style settings
 * except of reset, bold and reversed.
 * Note that on Windows terminals bold style is same as fgB color.
 */
enum class style {
    reset     = 0,
    bold      = 1,
    dim       = 2,
    italic    = 3,
    underline = 4,
    blink     = 5,
    rblink    = 6,
    reversed  = 7,
    conceal   = 8,
    crossed   = 9
};

enum class fg {
    black   = 30,
    red     = 31,
    green   = 32,
    yellow  = 33,
    blue    = 34,
    magenta = 35,
    cyan    = 36,
    gray    = 37,
    reset   = 39
};

enum class bg {
    black   = 40,
    red     = 41,
    green   = 42,
    yellow  = 43,
    blue    = 44,
    magenta = 45,
    cyan    = 46,
    gray    = 47,
    reset   = 49
};

enum class fgB {
    black   = 90,
    red     = 91,
    green   = 92,
    yellow  = 93,
    blue    = 94,
    magenta = 95,
    cyan    = 96,
    gray    = 97
};

enum class bgB {
    black   = 100,
    red     = 101,
    green   = 102,
    yellow  = 103,
    blue    = 104,
    magenta = 105,
    cyan    = 106,
    gray    = 107
};

enum class control {  // Behaviour of rang function calls
    Off   = 0,  // toggle off rang style/color calls
    Auto  = 1,  // (Default) autodect terminal and colorize if needed
    Force = 2  // force ansi color output to non terminal streams
};
// Use rang::setControlMode to set rang control mode

enum class winTerm {  // Windows Terminal Mode
    Auto   = 0,  // (Default) automatically detects wheter Ansi or Native API
    Ansi   = 1,  // Force use Ansi API
    Native = 2  // Force use Native API
};
// Use rang::setWinTermMode to explicitly set terminal API for Windows
// Calling rang::setWinTermMode have no effect on other OS

namespace rang_implementation {

    inline std::atomic<control> &controlMode() noexcept
    {
        static std::atomic<control> value(control::Auto);
        return value;
    }

    inline std::atomic<winTerm> &winTermMode() noexcept
    {
        static std::atomic<winTerm> termMode(winTerm::Auto);
        return termMode;
    }

    inline bool supportsColor() noexcept
    {
#if defined(OS_LINUX) || defined(OS_MAC)

        static const bool result = [] {
            const char *Terms[]
              = { "ansi",    "color",  "console", "cygwin", "gnome",
                  "konsole", "kterm",  "linux",   "msys",   "putty",
                  "rxvt",    "screen", "vt100",   "xterm" };

            const char *env_p = std::getenv("TERM");
            if (env_p == nullptr) {
                return false;
            }
            return std::any_of(std::begin(Terms), std::end(Terms),
                               [&](const char *term) {
                                   return std::strstr(env_p, term) != nullptr;
                               });
        }();

#elif defined(OS_WIN)
        // All windows versions support colors through native console methods
        static constexpr bool result = true;
#endif
        return result;
    }

#ifdef OS_WIN


    inline bool isMsysPty(int fd) noexcept
    {
        // Dynamic load for binary compability with old Windows
        const auto ptrGetFileInformationByHandleEx
          = reinterpret_cast<decltype(&GetFileInformationByHandleEx)>(
            GetProcAddress(GetModuleHandle(TEXT("kernel32.dll")),
                           "GetFileInformationByHandleEx"));
        if (!ptrGetFileInformationByHandleEx) {
            return false;
        }

        HANDLE h = reinterpret_cast<HANDLE>(_get_osfhandle(fd));
        if (h == INVALID_HANDLE_VALUE) {
            return false;
        }

        // Check that it's a pipe:
        if (GetFileType(h) != FILE_TYPE_PIPE) {
            return false;
        }

        // POD type is binary compatible with FILE_NAME_INFO from WinBase.h
        // It have the same alignment and used to avoid UB in caller code
        struct MY_FILE_NAME_INFO {
            DWORD FileNameLength;
            WCHAR FileName[MAX_PATH];
        };

        auto pNameInfo = std::unique_ptr<MY_FILE_NAME_INFO>(
          new (std::nothrow) MY_FILE_NAME_INFO());
        if (!pNameInfo) {
            return false;
        }

        // Check pipe name is template of
        // {"cygwin-","msys-"}XXXXXXXXXXXXXXX-ptyX-XX
        if (!ptrGetFileInformationByHandleEx(h, FileNameInfo, pNameInfo.get(),
                                             sizeof(MY_FILE_NAME_INFO))) {
            return false;
        }
        std::wstring name(pNameInfo->FileName, pNameInfo->FileNameLength / sizeof(WCHAR));
        if ((name.find(L"msys-") == std::wstring::npos
             && name.find(L"cygwin-") == std::wstring::npos)
            || name.find(L"-pty") == std::wstring::npos) {
            return false;
        }

        return true;
    }

#endif

    inline bool isTerminal(const std::streambuf *osbuf) noexcept
    {
        using std::cerr;
        using std::clog;
        using std::cout;
#if defined(OS_LINUX) || defined(OS_MAC)
        if (osbuf == cout.rdbuf()) {
            static const bool cout_term = isatty(fileno(stdout)) != 0;
            return cout_term;
        } else if (osbuf == cerr.rdbuf() || osbuf == clog.rdbuf()) {
            static const bool cerr_term = isatty(fileno(stderr)) != 0;
            return cerr_term;
        }
#elif defined(OS_WIN)
        if (osbuf == cout.rdbuf()) {
            static const bool cout_term
              = (_isatty(_fileno(stdout)) || isMsysPty(_fileno(stdout)));
            return cout_term;
        } else if (osbuf == cerr.rdbuf() || osbuf == clog.rdbuf()) {
            static const bool cerr_term
              = (_isatty(_fileno(stderr)) || isMsysPty(_fileno(stderr)));
            return cerr_term;
        }
#endif
        return false;
    }

    template <typename T>
    using enableStd = typename std::enable_if<
      std::is_same<T, rang::style>::value || std::is_same<T, rang::fg>::value
        || std::is_same<T, rang::bg>::value || std::is_same<T, rang::fgB>::value
        || std::is_same<T, rang::bgB>::value,
      std::ostream &>::type;


#ifdef OS_WIN

    struct SGR {  // Select Graphic Rendition parameters for Windows console
        BYTE fgColor;  // foreground color (0-15) lower 3 rgb bits + intense bit
        BYTE bgColor;  // background color (0-15) lower 3 rgb bits + intense bit
        BYTE bold;  // emulated as FOREGROUND_INTENSITY bit
        BYTE underline;  // emulated as BACKGROUND_INTENSITY bit
        BOOLEAN inverse;  // swap foreground/bold & background/underline
        BOOLEAN conceal;  // set foreground/bold to background/underline
    };

    enum class AttrColor : BYTE {  // Color attributes for console screen buffer
        black   = 0,
        red     = 4,
        green   = 2,
        yellow  = 6,
        blue    = 1,
        magenta = 5,
        cyan    = 3,
        gray    = 7
    };

    inline HANDLE getConsoleHandle(const std::streambuf *osbuf) noexcept
    {
        if (osbuf == std::cout.rdbuf()) {
            static const HANDLE hStdout = GetStdHandle(STD_OUTPUT_HANDLE);
            return hStdout;
        } else if (osbuf == std::cerr.rdbuf() || osbuf == std::clog.rdbuf()) {
            static const HANDLE hStderr = GetStdHandle(STD_ERROR_HANDLE);
            return hStderr;
        }
        return INVALID_HANDLE_VALUE;
    }

    inline bool setWinTermAnsiColors(const std::streambuf *osbuf) noexcept
    {
        HANDLE h = getConsoleHandle(osbuf);
        if (h == INVALID_HANDLE_VALUE) {
            return false;
        }
        DWORD dwMode = 0;
        if (!GetConsoleMode(h, &dwMode)) {
            return false;
        }
        dwMode |= ENABLE_VIRTUAL_TERMINAL_PROCESSING;
        if (!SetConsoleMode(h, dwMode)) {
            return false;
        }
        return true;
    }

    inline bool supportsAnsi(const std::streambuf *osbuf) noexcept
    {
        using std::cerr;
        using std::clog;
        using std::cout;
        if (osbuf == cout.rdbuf()) {
            static const bool cout_ansi
              = (isMsysPty(_fileno(stdout)) || setWinTermAnsiColors(osbuf));
            return cout_ansi;
        } else if (osbuf == cerr.rdbuf() || osbuf == clog.rdbuf()) {
            static const bool cerr_ansi
              = (isMsysPty(_fileno(stderr)) || setWinTermAnsiColors(osbuf));
            return cerr_ansi;
        }
        return false;
    }

    inline const SGR &defaultState() noexcept
    {
        static const SGR defaultSgr = []() -> SGR {
            CONSOLE_SCREEN_BUFFER_INFO info;
            WORD attrib = FOREGROUND_RED | FOREGROUND_GREEN | FOREGROUND_BLUE;
            if (GetConsoleScreenBufferInfo(GetStdHandle(STD_OUTPUT_HANDLE),
                                           &info)
                || GetConsoleScreenBufferInfo(GetStdHandle(STD_ERROR_HANDLE),
                                              &info)) {
                attrib = info.wAttributes;
            }
            SGR sgr     = { 0, 0, 0, 0, FALSE, FALSE };
            sgr.fgColor = attrib & 0x0F;
            sgr.bgColor = (attrib & 0xF0) >> 4;
            return sgr;
        }();
        return defaultSgr;
    }

    inline BYTE ansi2attr(BYTE rgb) noexcept
    {
        static const AttrColor rev[8]
          = { AttrColor::black,  AttrColor::red,  AttrColor::green,
              AttrColor::yellow, AttrColor::blue, AttrColor::magenta,
              AttrColor::cyan,   AttrColor::gray };
        return static_cast<BYTE>(rev[rgb]);
    }

    inline void setWinSGR(rang::bg col, SGR &state) noexcept
    {
        if (col != rang::bg::reset) {
            state.bgColor = ansi2attr(static_cast<BYTE>(col) - 40);
        } else {
            state.bgColor = defaultState().bgColor;
        }
    }

    inline void setWinSGR(rang::fg col, SGR &state) noexcept
    {
        if (col != rang::fg::reset) {
            state.fgColor = ansi2attr(static_cast<BYTE>(col) - 30);
        } else {
            state.fgColor = defaultState().fgColor;
        }
    }

    inline void setWinSGR(rang::bgB col, SGR &state) noexcept
    {
        state.bgColor = (BACKGROUND_INTENSITY >> 4)
          | ansi2attr(static_cast<BYTE>(col) - 100);
    }

    inline void setWinSGR(rang::fgB col, SGR &state) noexcept
    {
        state.fgColor
          = FOREGROUND_INTENSITY | ansi2attr(static_cast<BYTE>(col) - 90);
    }

    inline void setWinSGR(rang::style style, SGR &state) noexcept
    {
        switch (style) {
            case rang::style::reset: state = defaultState(); break;
            case rang::style::bold: state.bold = FOREGROUND_INTENSITY; break;
            case rang::style::underline:
            case rang::style::blink:
                state.underline = BACKGROUND_INTENSITY;
                break;
            case rang::style::reversed: state.inverse = TRUE; break;
            case rang::style::conceal: state.conceal = TRUE; break;
            default: break;
        }
    }

    inline SGR &current_state() noexcept
    {
        static SGR state = defaultState();
        return state;
    }

    inline WORD SGR2Attr(const SGR &state) noexcept
    {
        WORD attrib = 0;
        if (state.conceal) {
            if (state.inverse) {
                attrib = (state.fgColor << 4) | state.fgColor;
                if (state.bold)
                    attrib |= FOREGROUND_INTENSITY | BACKGROUND_INTENSITY;
            } else {
                attrib = (state.bgColor << 4) | state.bgColor;
                if (state.underline)
                    attrib |= FOREGROUND_INTENSITY | BACKGROUND_INTENSITY;
            }
        } else if (state.inverse) {
            attrib = (state.fgColor << 4) | state.bgColor;
            if (state.bold) attrib |= BACKGROUND_INTENSITY;
            if (state.underline) attrib |= FOREGROUND_INTENSITY;
        } else {
            attrib = state.fgColor | (state.bgColor << 4) | state.bold
              | state.underline;
        }
        return attrib;
    }

    template <typename T>
    inline void setWinColorAnsi(std::ostream &os, T const value)
    {
        os << "\033[" << static_cast<int>(value) << "m";
    }

    template <typename T>
    inline void setWinColorNative(std::ostream &os, T const value)
    {
        const HANDLE h = getConsoleHandle(os.rdbuf());
        if (h != INVALID_HANDLE_VALUE) {
            setWinSGR(value, current_state());
            // Out all buffered text to console with previous settings:
            os.flush();
            SetConsoleTextAttribute(h, SGR2Attr(current_state()));
        }
    }

    template <typename T>
    inline enableStd<T> setColor(std::ostream &os, T const value)
    {
        if (winTermMode() == winTerm::Auto) {
            if (supportsAnsi(os.rdbuf())) {
                setWinColorAnsi(os, value);
            } else {
                setWinColorNative(os, value);
            }
        } else if (winTermMode() == winTerm::Ansi) {
            setWinColorAnsi(os, value);
        } else {
            setWinColorNative(os, value);
        }
        return os;
    }
#else
    template <typename T>
    inline enableStd<T> setColor(std::ostream &os, T const value)
    {
        return os << "\033[" << static_cast<int>(value) << "m";
    }
#endif
}  // namespace rang_implementation

template <typename T>
inline rang_implementation::enableStd<T> operator<<(std::ostream &os,
                                                    const T value)
{
    const control option = rang_implementation::controlMode();
    switch (option) {
        case control::Auto:
            return rang_implementation::supportsColor()
                && rang_implementation::isTerminal(os.rdbuf())
              ? rang_implementation::setColor(os, value)
              : os;
        case control::Force: return rang_implementation::setColor(os, value);
        default: return os;
    }
}

inline void setWinTermMode(const rang::winTerm value) noexcept
{
    rang_implementation::winTermMode() = value;
}

inline void setControlMode(const control value) noexcept
{
    rang_implementation::controlMode() = value;
}

}  // namespace rang

#undef OS_LINUX
#undef OS_WIN
#undef OS_MAC

#endif /* ifndef RANG_DOT_HPP */