/**
 * @file   utils/color_out.cpp
 * @author Martin Pulec     <pulec@cesnet.cz>
 */
/*
 * Copyright (c) 2018-2023 CESNET, z. s. p. o.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, is permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * 3. Neither the name of CESNET nor the names of its contributors may be
 *    used to endorse or promote products derived from this software without
 *    specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING,
 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
 * EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#include "config_unix.h"
#include "config_win32.h"
#endif

#include <unistd.h>

#include <cstdarg>
#include <iostream>
#include <memory>

#include "debug.h"
#include "host.h"
#include "utils/color_out.h"

using std::cout;
using std::string;

static bool color_stdout;

#ifdef _WIN32
/// Taken from [rang](https://github.com/agauniyal/rang)
static bool setWinTermAnsiColors(DWORD stream) {
        HANDLE h = GetStdHandle(stream);
        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;
}

/// Taken from [rang](https://github.com/agauniyal/rang)
static bool isMsysPty(int fd) {
        // Dynamic load for binary compability with old Windows
        const auto ptrGetFileInformationByHandleEx
                = reinterpret_cast<decltype(&GetFileInformationByHandleEx)>(reinterpret_cast<void *>(
                                        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 // defined _WIN32

// conditional include here (and below) is to allow compilation outside UG
// without the need to link with host.o, which seems to be tricky
#ifdef HAVE_CONFIG_H
ADD_TO_PARAM("log-nocolor", "* log-nocolor\n"
                 "  Force disable ANSI text formatting.\n");
#endif
/**
 * @returns whether stdout can process ANSI escape sequences
 */
bool color_output_init() {
#ifdef HAVE_CONFIG_H
        if(get_commandline_param("log-nocolor")){
                color_stdout = false;
                return false;
        }
#endif
#ifdef _WIN32
        color_stdout = isMsysPty(fileno(stdout)) || (_isatty(fileno(stdout)) && setWinTermAnsiColors(STD_OUTPUT_HANDLE));
#else
        color_stdout = isatty(fileno(stdout));
#endif
        return color_stdout;
}

template<class OutputIt>
static int prune_ansi_sequences(const char *in, OutputIt out) {
        char c = *in;
        bool in_control = false;
        int written = 0;
        while (c != '\0') {
                switch (c) {
                        case '\033':
                                in_control = true;
                                break;
                        case 'm':
                                   if (in_control) {
                                           in_control = false;
                                           break;
                                   }
                                   // fall through
                        default:
                                   if (!in_control) {
                                           *out++ = c;
                                           written++;
                                   }
                }
                c = *++in;
        }
        *out = '\0';
        return written;
}

string prune_ansi_sequences_str(const char *in) {
        string out;
        prune_ansi_sequences(in, std::back_inserter(out));
        return out;
}

void prune_ansi_sequences_inplace(std::string& str){
        auto c_ptr = str.data();
        auto len = prune_ansi_sequences(c_ptr, c_ptr);
        str.resize(len);
}

/// @returns cstr
char *prune_ansi_sequences_inplace_cstr(char *cstr) {
        prune_ansi_sequences(cstr, cstr);
        return cstr;
}

int color_printf(const char *format, ...) {
        va_list ap;
        va_start(ap, format);
        int size = vsnprintf(NULL, 0, format, ap);
        va_end(ap);

        // format the string
        auto buf = get_log_output().get_buffer();
        buf.append(size + 1, '\0');
        va_start(ap, format);
        vsnprintf(buf.data(), size + 1, format, ap);
        va_end(ap);

        if (!color_stdout) {
                int len = prune_ansi_sequences(buf.data(), buf.data());
                buf.get().resize(len);
        }

        buf.submit_raw();
        return size;
}