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#include "qsqlindex.h"

#include "qsqlfield.h"

#include "qstringlist.h"

QT_BEGIN_NAMESPACE

/*!

    \class QSqlIndex

    \brief The QSqlIndex class provides functions to manipulate and

    describe database indexes.

    \ingroup database

    \inmodule QtSql

    An \e index refers to a single table or view in a database.

    Information about the fields that comprise the index can be used

    to generate SQL statements.

*/

/*!

    Constructs an empty index using the cursor name \a cursorname and

    index name \a name.

*/

QSqlIndex::QSqlIndex(const QString& cursorname, const QString& name)

    : cursor(cursorname), nm(name)

{

}

/*!

    Constructs a copy of \a other.

*/

QSqlIndex::QSqlIndex(const QSqlIndex& other)

    : QSqlRecord(other), cursor(other.cursor), nm(other.nm), sorts(other.sorts)

{

}

/*!

    Sets the index equal to \a other.

*/

QSqlIndex& QSqlIndex::operator=(const QSqlIndex& other)

{

    cursor = other.cursor;

    nm = other.nm;

    sorts = other.sorts;

    QSqlRecord::operator=(other);

    return *this;

}

/*!

    Destroys the object and frees any allocated resources.

*/

QSqlIndex::~QSqlIndex()

{

}

/*!

    Sets the name of the index to \a name.

*/

void QSqlIndex::setName(const QString& name)

{

    nm = name;

}

/*!

    \fn QString QSqlIndex::name() const

    Returns the name of the index.

*/

/*!

    Appends the field \a field to the list of indexed fields. The

    field is appended with an ascending sort order.

*/

void QSqlIndex::append(const QSqlField& field)

{

    append(field, false);

}

/*!

    \overload

    Appends the field \a field to the list of indexed fields. The

    field is appended with an ascending sort order, unless \a desc is

    true.

*/

void QSqlIndex::append(const QSqlField& field, bool desc)

{

    sorts.append(desc);

    QSqlRecord::append(field);

}

/*!

    Returns true if field \a i in the index is sorted in descending

    order; otherwise returns false.

*/

bool QSqlIndex::isDescending(int i) const

{

    if (i >= 0 && i < sorts.size())

        return sorts[i];

    return false;

}

/*!

    If \a desc is true, field \a i is sorted in descending order.

    Otherwise, field \a i is sorted in ascending order (the default).

    If the field does not exist, nothing happens.

*/

void QSqlIndex::setDescending(int i, bool desc)

{

    if (i >= 0 && i < sorts.size())

        sorts[i] = desc;

}

#ifdef QT3_SUPPORT

/*!

    Returns a comma-separated list of all the index's field names as a

    string. This string is suitable, for example, for generating a

    SQL SELECT statement. Only generated fields are included in the

    list (see \l{isGenerated()}). If a \a prefix is specified, e.g. a

    table name, it is prepended before all field names in the form:

    "\a{prefix}.<fieldname>"

    If \a sep is specified, each field is separated by \a sep. If \a

    verbose is true (the default), each field contains a suffix

    indicating an ASCending or DESCending sort order.

*/

QString QSqlIndex::toString(const QString& prefix, const QString& sep, bool verbose) const

{

    QString s;

    bool comma = false;

    for (int i = 0; i < count(); ++i) {

        if(comma)

            s += sep + QLatin1Char(' ');

        s += createField(i, prefix, verbose);

        comma = true;

    }

    return s;

}

/*!

    Returns a list of all the index's field names. Only generated

    fields are included in the list (see \l{isGenerated()}). If a \a

    prefix is specified, e.g. a table name, all fields are prefixed in

    the form:

    "\a{prefix}.<fieldname>"

    If \a verbose is true (the default), each field contains a suffix

    indicating an ASCending or DESCending sort order.

    Note that if you want to iterate over the list, you should iterate

    over a copy, e.g.

    \snippet doc/src/snippets/code/src_sql_kernel_qsqlindex.cpp 0

*/

QStringList QSqlIndex::toStringList(const QString& prefix, bool verbose) const

{

    QStringList s;

    for (int i = 0; i < count(); ++i)

        s += createField(i, prefix, verbose);

    return s;

}

#endif

/*! \internal

  Creates a string representing the field number \a i using prefix \a

  prefix. If \a verbose is true, ASC or DESC is included in the field

  description if the field is sorted in ASCending or DESCending order.

*/

QString QSqlIndex::createField(int i, const QString& prefix, bool verbose) const

{

    QString f;

    if (!prefix.isEmpty())

        f += prefix + QLatin1Char('.');

    f += field(i).name();

    if (verbose)

        f += QLatin1Char(' ') + QString((isDescending(i)

                    ? QLatin1String("DESC") : QLatin1String("ASC")));

    return f;

}

/*!

    \fn QString QSqlIndex::cursorName() const

    Returns the name of the cursor which the index is associated with.

*/

/*!

    Sets the name of the cursor that the index is associated with to

    \a cursorName.

*/

void QSqlIndex::setCursorName(const QString& cursorName)

{

    cursor = cursorName;

}

QT_END_NAMESPACE