/*
    Copyright (C) 2007 by Robert Knight <robertknight@gmail.com>

    Rewritten for QT4 by e_k <e_k at users.sourceforge.net>, Copyright (C)2008

    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 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.
*/

// Own
#include "ShellCommand.h"

//some versions of gcc(4.3) require explicit include
#include <cstdlib>

// expands environment variables in 'text'
// function copied from kdelibs/kio/kio/kurlcompletion.cpp
static bool expandEnv(QString& text);

ShellCommand::ShellCommand(const QString& fullCommand)
{
    bool inQuotes = false;

    QString builder;

    for ( int i = 0 ; i < fullCommand.count() ; i++ )
    {
        QChar ch = fullCommand[i];

        const bool isLastChar = ( i == fullCommand.count() - 1 );
        const bool isQuote = ( ch == '\'' || ch == '\"' );

        if ( !isLastChar && isQuote )
            inQuotes = !inQuotes;
        else
        { 
            if ( (!ch.isSpace() || inQuotes) && !isQuote )
                builder.append(ch);

            if ( (ch.isSpace() && !inQuotes) || ( i == fullCommand.count()-1 ) )
            {
                _arguments << builder;      
                builder.clear(); 
            }
        }
    }
}
ShellCommand::ShellCommand(const QString& command , const QStringList& arguments)
{
    _arguments = arguments;
    
    if ( !_arguments.isEmpty() )
        _arguments[0] == command;
}
QString ShellCommand::fullCommand() const
{
    return _arguments.join(QChar(' '));
}
QString ShellCommand::command() const
{
    if ( !_arguments.isEmpty() )
        return _arguments[0];
    else
        return QString();
}
QStringList ShellCommand::arguments() const
{
    return _arguments;
}
bool ShellCommand::isRootCommand() const
{
    Q_ASSERT(0); // not implemented yet
    return false;
}
bool ShellCommand::isAvailable() const
{
    Q_ASSERT(0); // not implemented yet
    return false; 
}
QStringList ShellCommand::expand(const QStringList& items)
{
    QStringList result;

    foreach( QString item , items )
        result << expand(item);

    return result;
}
QString ShellCommand::expand(const QString& text)
{
    QString result = text;
    expandEnv(result);
    return result;
}

/*
 * expandEnv
 *
 * Expand environment variables in text. Escaped '$' characters are ignored.
 * Return true if any variables were expanded
 */
static bool expandEnv( QString &text )
{
	// Find all environment variables beginning with '$'
	//
	int pos = 0;

	bool expanded = false;

	while ( (pos = text.indexOf(QLatin1Char('$'), pos)) != -1 ) {

		// Skip escaped '$'
		//
		if ( pos > 0 && text.at(pos-1) == QLatin1Char('\\') ) {
			pos++;
		}
		// Variable found => expand
		//
		else {
			// Find the end of the variable = next '/' or ' '
			//
			int pos2 = text.indexOf( QLatin1Char(' '), pos+1 );
			int pos_tmp = text.indexOf( QLatin1Char('/'), pos+1 );

			if ( pos2 == -1 || (pos_tmp != -1 && pos_tmp < pos2) )
				pos2 = pos_tmp;

			if ( pos2 == -1 )
				pos2 = text.length();

			// Replace if the variable is terminated by '/' or ' '
			// and defined
			//
			if ( pos2 >= 0 ) {
				int len	= pos2 - pos;
				QString key	= text.mid( pos+1, len-1);
				QString value =
					QString::fromLocal8Bit( ::getenv(key.toLocal8Bit()) );

				if ( !value.isEmpty() ) {
					expanded = true;
					text.replace( pos, len, value );
					pos = pos + value.length();
				}
				else {
					pos = pos2;
				}
			}
		}
	}

	return expanded;
}