# -*- coding: utf-8 -*-

"""
/***************************************************************************
Name                 : DB Manager
Description          : Database manager plugin for QGIS
Date                 : May 23, 2011
copyright            : (C) 2011 by Giuseppe Sucameli
email                : brush.tyler@gmail.com

 ***************************************************************************/

/***************************************************************************
 *                                                                         *
 *   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.                                   *
 *                                                                         *
 ***************************************************************************/
"""

from PyQt4.QtCore import SIGNAL

from ..data_model import TableDataModel, SqlResultModel

class PGTableDataModel(TableDataModel):
        def __init__(self, table, parent=None):
                self.cursor = None
                TableDataModel.__init__(self, table, parent)

                if self.table.rowCount is None:
                        self.table.refreshRowCount()
                        if self.table.rowCount is None:
                                return

                self.connect(self.table, SIGNAL("aboutToChange"), self._deleteCursor)
                self._createCursor()

        def _createCursor(self):
                fields_txt = u", ".join(self.fields)
                table_txt = self.db.quoteId( (self.table.schemaName(), self.table.name) )

                self.cursor = self.db._get_cursor()
                sql = u"SELECT %s FROM %s" % (fields_txt, table_txt)
                self.db._execute(self.cursor, sql)

        def _sanitizeTableField(self, field):
                # get fields, ignore geometry columns
                if field.dataType.lower() == "geometry":
                        return u"CASE WHEN %(fld)s IS NULL THEN NULL ELSE GeometryType(%(fld)s) END AS %(fld)s" % {'fld': self.db.quoteId(field.name)}
                elif field.dataType.lower() == "raster":
                        return u"CASE WHEN %(fld)s IS NULL THEN NULL ELSE 'RASTER' END AS %(fld)s" % {'fld': self.db.quoteId(field.name)}
                return u"%s::text" % self.db.quoteId(field.name)

        def _deleteCursor(self):
                self.db._close_cursor(self.cursor)
                self.cursor = None

        def __del__(self):
                self.disconnect(self.table, SIGNAL("aboutToChange"), self._deleteCursor)
                self._deleteCursor()
                pass    # print "PGTableModel.__del__"

        def fetchMoreData(self, row_start):
                if not self.cursor:
                        self._createCursor()

                try:
                        self.cursor.scroll(row_start, mode='absolute')
                except self.db.error_types():
                        self._deleteCursor()
                        return self.fetchMoreData(row_start)

                self.resdata = self.cursor.fetchmany(self.fetchedCount)
                self.fetchedFrom = row_start


class PGSqlResultModel(SqlResultModel):
        pass
