/*
 *  Copyright (C) 2017 KeePassXC Team <team@keepassxc.org>
 *
 *  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 2 or (at your option)
 *  version 3 of the License.
 *
 *  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, see <http://www.gnu.org/licenses/>.
 */

#include "Utils.h"

#ifdef Q_OS_WIN
#include <windows.h>
#else
#include <termios.h>
#include <unistd.h>
#endif

#include <QProcess>

namespace Utils
{
/**
 * STDOUT file handle for the CLI.
 */
FILE* STDOUT = stdout;

/**
 * STDERR file handle for the CLI.
 */
FILE* STDERR = stderr;

/**
 * STDIN file handle for the CLI.
 */
FILE* STDIN = stdin;

void setStdinEcho(bool enable = true)
{
#ifdef Q_OS_WIN
    HANDLE hIn = GetStdHandle(STD_INPUT_HANDLE);
    DWORD mode;
    GetConsoleMode(hIn, &mode);

    if (enable) {
        mode |= ENABLE_ECHO_INPUT;
    } else {
        mode &= ~ENABLE_ECHO_INPUT;
    }

    SetConsoleMode(hIn, mode);

#else
    struct termios t;
    tcgetattr(STDIN_FILENO, &t);

    if (enable) {
        t.c_lflag |= ECHO;
    } else {
        t.c_lflag &= ~ECHO;
    }

    tcsetattr(STDIN_FILENO, TCSANOW, &t);
#endif
}

QStringList nextPasswords = {};

/**
 * Set the next password returned by \link getPassword() instead of reading it from STDIN.
 * Multiple calls to this method will fill a queue of passwords.
 * This function is intended for testing purposes.
 *
 * @param password password to return next
 */
void setNextPassword(const QString& password)
{
    nextPasswords.append(password);
}

/**
 * Read a user password from STDIN or return a password previously
 * set by \link setNextPassword().
 *
 * @return the password
 */
QString getPassword()
{
    QTextStream out(STDOUT, QIODevice::WriteOnly);

    // return preset password if one is set
    if (!nextPasswords.isEmpty()) {
        auto password = nextPasswords.takeFirst();
        // simulate user entering newline
        out << endl;
        return password;
    }

    QTextStream in(STDIN, QIODevice::ReadOnly);

    setStdinEcho(false);
    QString line = in.readLine();
    setStdinEcho(true);
    out << endl;

    return line;
}

/**
 * A valid and running event loop is needed to use the global QClipboard,
 * so we need to use this from the CLI.
 */
int clipText(const QString& text)
{
    QTextStream err(Utils::STDERR);

    QString programName = "";
    QStringList arguments;

#ifdef Q_OS_UNIX
    programName = "xclip";
    arguments << "-i"
              << "-selection"
              << "clipboard";
#endif

#ifdef Q_OS_MACOS
    programName = "pbcopy";
#endif

#ifdef Q_OS_WIN
    programName = "clip";
#endif

    if (programName.isEmpty()) {
        err << QObject::tr("No program defined for clipboard manipulation");
        err.flush();
        return EXIT_FAILURE;
    }

    auto* clipProcess = new QProcess(nullptr);
    clipProcess->start(programName, arguments);
    clipProcess->waitForStarted();

    if (clipProcess->state() != QProcess::Running) {
        err << QObject::tr("Unable to start program %1").arg(programName);
        err.flush();
        return EXIT_FAILURE;
    }

    if (clipProcess->write(text.toLatin1()) == -1) {
        qDebug("Unable to write to process : %s", qPrintable(clipProcess->errorString()));
    }
    clipProcess->waitForBytesWritten();
    clipProcess->closeWriteChannel();
    clipProcess->waitForFinished();

    return clipProcess->exitCode();
}

}   // namespace Utils