/****************************************************************************
** $Id$
**
** Implementation of QStringList
**
** Created : 990406
**
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#include "qstringlist.h"

#ifndef QT_NO_STRINGLIST
#include "qregexp.h"
#include "qstrlist.h"
#include "qdatastream.h"
#include "qtl.h"

/*!
    \class QStringList qstringlist.h
    \reentrant
    \brief The QStringList class provides a list of strings.

    \ingroup tools
    \ingroup shared
    \ingroup text
    \mainclass

    It is used to store and manipulate strings that logically belong
    together. Essentially QStringList is a QValueList of QString
    objects. Unlike QStrList, which stores pointers to characters,
    QStringList holds real QString objects. It is the class of choice
    whenever you work with Unicode strings. QStringList is part of the
    \link qtl.html Qt Template Library\endlink.

    Like QString itself, QStringList objects are implicitly shared.
    Passing them around as value-parameters is both fast and safe.

    Strings can be added to a list using append(), operator+=() or
    operator<<(), e.g.
    \code
    QStringList fonts;
    fonts.append( "Times" );
    fonts += "Courier";
    fonts += "Courier New";
    fonts << "Helvetica [Cronyx]" << "Helvetica [Adobe]";
    \endcode

    String lists have an iterator, QStringList::Iterator(), e.g.
    \code
    for ( QStringList::Iterator it = fonts.begin(); it != fonts.end(); ++it ) {
	cout << *it << ":";
    }
    cout << endl;
    // Output:
    //	Times:Courier:Courier New:Helvetica [Cronyx]:Helvetica [Adobe]:
    \endcode

    Many Qt functions return const string lists; to iterate over these
    you should make a copy and iterate over the copy.

    You can concatenate all the strings in a string list into a single
    string (with an optional separator) using join(), e.g.
    \code
    QString allFonts = fonts.join( ", " );
    cout << allFonts << endl;
    // Output:
    //	Times, Courier, Courier New, Helvetica [Cronyx], Helvetica [Adobe]
    \endcode

    You can sort the list with sort(), and extract a new list which
    contains only those strings which contain a particular substring
    (or match a particular regular expression) using the grep()
    functions, e.g.
    \code
    fonts.sort();
    cout << fonts.join( ", " ) << endl;
    // Output:
    //	Courier, Courier New, Helvetica [Adobe], Helvetica [Cronyx], Times

    QStringList helveticas = fonts.grep( "Helvetica" );
    cout << helveticas.join( ", " ) << endl;
    // Output:
    //	Helvetica [Adobe], Helvetica [Cronyx]
    \endcode

    Existing strings can be split into string lists with character,
    string or regular expression separators, e.g.
    \code
    QString s = "Red\tGreen\tBlue";
    QStringList colors = QStringList::split( "\t", s );
    cout << colors.join( ", " ) << endl;
    // Output:
    //	Red, Green, Blue
    \endcode
*/

/*!
    \fn QStringList::QStringList()

    Creates an empty string list.
*/

/*!
    \fn QStringList::QStringList( const QStringList& l )

    Creates a copy of the list \a l. This function is very fast
    because QStringList is implicitly shared. In most situations this
    acts like a deep copy, for example, if this list or the original
    one or some other list referencing the same shared data is
    modified, the modifying list first makes a copy, i.e.
    copy-on-write.
    In a threaded environment you may require a real deep copy
    \omit see \l QDeepCopy\endomit.
*/

/*!
    \fn QStringList::QStringList (const QString & i)

    Constructs a string list consisting of the single string \a i.
    Longer lists are easily created as follows:

    \code
    QStringList items;
    items << "Buy" << "Sell" << "Update" << "Value";
    \endcode
*/

/*!
    \fn QStringList::QStringList (const char* i)

    Constructs a string list consisting of the single latin-1 string \a i.
*/

/*!
    \fn QStringList::QStringList( const QValueList<QString>& l )

    Constructs a new string list that is a copy of \a l.
*/

/*!
    Sorts the list of strings in ascending case-sensitive order.

    Sorting is very fast. It uses the \link qtl.html Qt Template
    Library's\endlink efficient HeapSort implementation that has a
    time complexity of O(n*log n).

    If you want to sort your strings in an arbitrary order consider
    using a QMap. For example you could use a QMap\<QString,QString\>
    to create a case-insensitive ordering (e.g. mapping the lowercase
    text to the text), or a QMap\<int,QString\> to sort the strings by
    some integer index, etc.
*/
void QStringList::sort()
{
    qHeapSort( *this );
}

/*!
    \overload

    This version of the function uses a QChar as separator, rather
    than a regular expression.

    \sa join() QString::section()
*/

QStringList QStringList::split( const QChar &sep, const QString &str,
				bool allowEmptyEntries )
{
    return split( QString(sep), str, allowEmptyEntries );
}

/*!
    \overload

    This version of the function uses a QString as separator, rather
    than a regular expression.

    If \a sep is an empty string, the return value is a list of
    one-character strings: split( QString( "" ), "four" ) returns the
    four-item list, "f", "o", "u", "r".

    If \a allowEmptyEntries is TRUE, an empty string is inserted in
    the list wherever the separator matches twice without intervening
    text.

    \sa join() QString::section()
*/

QStringList QStringList::split( const QString &sep, const QString &str,
				bool allowEmptyEntries )
{
    QStringList lst;

    int j = 0;
    int i = str.find( sep, j );

    while ( i != -1 ) {
	if ( i > j && i <= (int)str.length() )
	    lst << str.mid( j, i - j );
	else if ( allowEmptyEntries )
	    lst << QString::null;
	j = i + sep.length();
	i = str.find( sep, sep.length() > 0 ? j : j+1 );
    }

    int l = str.length() - 1;
    if ( str.mid( j, l - j + 1 ).length() > 0 )
	lst << str.mid( j, l - j + 1 );
    else if ( allowEmptyEntries )
	lst << QString::null;

    return lst;
}

#ifndef QT_NO_REGEXP
/*!
    Splits the string \a str into strings wherever the regular
    expression \a sep occurs, and returns the list of those strings.

    If \a allowEmptyEntries is TRUE, an empty string is inserted in
    the list wherever the separator matches twice without intervening
    text.

    For example, if you split the string "a,,b,c" on commas, split()
    returns the three-item list "a", "b", "c" if \a allowEmptyEntries
    is FALSE (the default), and the four-item list "a", "", "b", "c"
    if \a allowEmptyEntries is TRUE.

    If \a sep does not match anywhere in \a str, split() returns a
    list consisting of the single string \a str.

    \sa join() QString::section()
*/

QStringList QStringList::split( const QRegExp &sep, const QString &str,
				bool allowEmptyEntries )
{
    QStringList lst;

    QRegExp tep = sep;

    int j = 0;
    int i = tep.search( str, j );

    while ( i != -1 ) {
	if ( str.mid( j, i - j ).length() > 0 )
	    lst << str.mid( j, i - j );
	else if ( allowEmptyEntries )
	    lst << QString::null;
	if ( tep.matchedLength() == 0 )
	    j = i + 1;
	else
	    j = i + tep.matchedLength();
	i = tep.search( str, j );
    }

    int l = str.length() - 1;
    if ( str.mid( j, l - j + 1 ).length() > 0 )
	lst << str.mid( j, l - j + 1 );
    else if ( allowEmptyEntries )
	lst << QString::null;

    return lst;
}
#endif

/*!
    Returns a list of all strings containing the substring \a str.

    If \a cs is TRUE, the grep is done case-sensitively; otherwise
    case is ignored.
*/

QStringList QStringList::grep( const QString &str, bool cs ) const
{
    QStringList res;
    for ( QStringList::ConstIterator it = begin(); it != end(); ++it )
	if ( (*it).contains(str, cs) )
	    res << *it;

    return res;
}

#ifndef QT_NO_REGEXP
/*!
    \overload

    Returns a list of all the strings that match the regular
    expression \a expr.
*/

QStringList QStringList::grep( const QRegExp &expr ) const
{
    QStringList res;
    for ( QStringList::ConstIterator it = begin(); it != end(); ++it )
	if ( (*it).contains(expr) )
	    res << *it;

    return res;
}
#endif

/*!
    Joins the string list into a single string with each element
    separated by the string \a sep (which can be empty).

    \sa split()
*/
QString QStringList::join( const QString &sep ) const
{
    QString res;
    bool alredy = FALSE;
    for ( QStringList::ConstIterator it = begin(); it != end(); ++it ) {
	if ( alredy )
	    res += sep;
	alredy = TRUE;
	res += *it;
    }

    return res;
}

#ifndef QT_NO_DATASTREAM
Q_EXPORT QDataStream &operator>>( QDataStream & s, QStringList& l )
{
    return s >> (QValueList<QString>&)l;
}

Q_EXPORT QDataStream &operator<<( QDataStream & s, const QStringList& l )
{
    return s << (const QValueList<QString>&)l;
}
#endif

/*!
    Converts from an ASCII-QStrList \a ascii to a QStringList (Unicode).
*/
QStringList QStringList::fromStrList(const QStrList& ascii)
{
    QStringList res;
    const char * s;
    for ( QStrListIterator it(ascii); (s=it.current()); ++it )
	res << s;
    return res;
}

#endif //QT_NO_STRINGLIST