sync with upstream

1 files changed, 745 insertions, 0 deletions

diff --git a/xbmc/utils/DatabaseUtils.cpp b/xbmc/utils/DatabaseUtils.cpp
new file mode 100644
index 0000000..fdff052
--- /dev/null
+++ b/xbmc/utils/DatabaseUtils.cpp
@@ -0,0 +1,745 @@
+/*
+ *  Copyright (C) 2012-2018 Team Kodi
+ *  This file is part of Kodi - https://kodi.tv
+ *
+ *  SPDX-License-Identifier: GPL-2.0-or-later
+ *  See LICENSES/README.md for more information.
+ */
+
+#include "DatabaseUtils.h"
+
+#include "dbwrappers/dataset.h"
+#include "music/MusicDatabase.h"
+#include "utils/StringUtils.h"
+#include "utils/Variant.h"
+#include "utils/log.h"
+#include "video/VideoDatabase.h"
+
+#include <sstream>
+
+MediaType DatabaseUtils::MediaTypeFromVideoContentType(int videoContentType)
+{
+  VIDEODB_CONTENT_TYPE type = (VIDEODB_CONTENT_TYPE)videoContentType;
+  switch (type)
+  {
+    case VIDEODB_CONTENT_MOVIES:
+      return MediaTypeMovie;
+
+    case VIDEODB_CONTENT_MOVIE_SETS:
+      return MediaTypeVideoCollection;
+
+    case VIDEODB_CONTENT_TVSHOWS:
+      return MediaTypeTvShow;
+
+    case VIDEODB_CONTENT_EPISODES:
+      return MediaTypeEpisode;
+
+    case VIDEODB_CONTENT_MUSICVIDEOS:
+      return MediaTypeMusicVideo;
+
+    default:
+      break;
+  }
+
+  return MediaTypeNone;
+}
+
+std::string DatabaseUtils::GetField(Field field, const MediaType &mediaType, DatabaseQueryPart queryPart)
+{
+  if (field == FieldNone || mediaType == MediaTypeNone)
+    return "";
+
+  if (mediaType == MediaTypeAlbum)
+  {
+    if (field == FieldId) return "albumview.idAlbum";
+    else if (field == FieldAlbum) return "albumview.strAlbum";
+    else if (field == FieldArtist || field == FieldAlbumArtist) return "albumview.strArtists";
+    else if (field == FieldGenre)
+      return "albumview.strGenres";
+    else if (field == FieldYear)
+      return "albumview.strReleaseDate";
+    else if (field == FieldOrigYear || field == FieldOrigDate)
+      return "albumview.strOrigReleaseDate";
+    else if (field == FieldMoods) return "albumview.strMoods";
+    else if (field == FieldStyles) return "albumview.strStyles";
+    else if (field == FieldThemes) return "albumview.strThemes";
+    else if (field == FieldReview) return "albumview.strReview";
+    else if (field == FieldMusicLabel) return "albumview.strLabel";
+    else if (field == FieldAlbumType) return "albumview.strType";
+    else if (field == FieldCompilation) return "albumview.bCompilation";
+    else if (field == FieldRating) return "albumview.fRating";
+    else if (field == FieldVotes) return "albumview.iVotes";
+    else if (field == FieldUserRating) return "albumview.iUserrating";
+    else if (field == FieldDateAdded) return "albumview.dateAdded";
+    else if (field == FieldDateNew) return "albumview.dateNew";
+    else if (field == FieldDateModified) return "albumview.dateModified";
+    else if (field == FieldPlaycount) return "albumview.iTimesPlayed";
+    else if (field == FieldLastPlayed) return "albumview.lastPlayed";
+    else if (field == FieldTotalDiscs)
+      return "albumview.iDiscTotal";
+    else if (field == FieldAlbumStatus)
+        return "albumview.strReleaseStatus";
+  }
+  else if (mediaType == MediaTypeSong)
+  {
+    if (field == FieldId) return "songview.idSong";
+    else if (field == FieldTitle) return "songview.strTitle";
+    else if (field == FieldTrackNumber) return "songview.iTrack";
+    else if (field == FieldTime) return "songview.iDuration";
+    else if (field == FieldYear)
+      return "songview.strReleaseDate";
+    else if (field == FieldOrigYear || field == FieldOrigDate)
+      return "songview.strOrigReleaseDate";
+    else if (field == FieldFilename) return "songview.strFilename";
+    else if (field == FieldPlaycount) return "songview.iTimesPlayed";
+    else if (field == FieldStartOffset) return "songview.iStartOffset";
+    else if (field == FieldEndOffset) return "songview.iEndOffset";
+    else if (field == FieldLastPlayed) return "songview.lastPlayed";
+    else if (field == FieldRating) return "songview.rating";
+    else if (field == FieldVotes) return "songview.votes";
+    else if (field == FieldUserRating) return "songview.userrating";
+    else if (field == FieldComment) return "songview.comment";
+    else if (field == FieldMoods) return "songview.mood";
+    else if (field == FieldAlbum) return "songview.strAlbum";
+    else if (field == FieldPath) return "songview.strPath";
+    else if (field == FieldArtist || field == FieldAlbumArtist) return "songview.strArtists";
+    else if (field == FieldGenre)
+      return "songview.strGenres";
+    else if (field == FieldDateAdded) return "songview.dateAdded";
+    else if (field == FieldDateNew) return "songview.dateNew";
+    else if (field == FieldDateModified) return "songview.dateModified";
+
+    else if (field == FieldDiscTitle)
+      return "songview.strDiscSubtitle";
+    else if (field == FieldBPM)
+        return "songview.iBPM";
+    else if (field == FieldMusicBitRate)
+        return "songview.iBitRate";
+    else if (field == FieldSampleRate)
+        return "songview.iSampleRate";
+    else if (field == FieldNoOfChannels)
+        return "songview.iChannels";
+  }
+  else if (mediaType == MediaTypeArtist)
+  {
+    if (field == FieldId) return "artistview.idArtist";
+    else if (field == FieldArtistSort) return "artistview.strSortName";
+    else if (field == FieldArtist) return "artistview.strArtist";
+    else if (field == FieldArtistType) return "artistview.strType";
+    else if (field == FieldGender) return "artistview.strGender";
+    else if (field == FieldDisambiguation) return "artistview.strDisambiguation";
+    else if (field == FieldGenre) return "artistview.strGenres";
+    else if (field == FieldMoods) return "artistview.strMoods";
+    else if (field == FieldStyles) return "artistview.strStyles";
+    else if (field == FieldInstruments) return "artistview.strInstruments";
+    else if (field == FieldBiography) return "artistview.strBiography";
+    else if (field == FieldBorn) return "artistview.strBorn";
+    else if (field == FieldBandFormed) return "artistview.strFormed";
+    else if (field == FieldDisbanded) return "artistview.strDisbanded";
+    else if (field == FieldDied) return "artistview.strDied";
+    else if (field == FieldDateAdded) return "artistview.dateAdded";
+    else if (field == FieldDateNew) return "artistview.dateNew";
+    else if (field == FieldDateModified) return "artistview.dateModified";
+  }
+  else if (mediaType == MediaTypeMusicVideo)
+  {
+    std::string result;
+    if (field == FieldId) return "musicvideo_view.idMVideo";
+    else if (field == FieldTitle) result = StringUtils::Format("musicvideo_view.c%02d",VIDEODB_ID_MUSICVIDEO_TITLE);
+    else if (field == FieldTime) result = StringUtils::Format("musicvideo_view.c%02d", VIDEODB_ID_MUSICVIDEO_RUNTIME);
+    else if (field == FieldDirector) result = StringUtils::Format("musicvideo_view.c%02d", VIDEODB_ID_MUSICVIDEO_DIRECTOR);
+    else if (field == FieldStudio) result = StringUtils::Format("musicvideo_view.c%02d", VIDEODB_ID_MUSICVIDEO_STUDIOS);
+    else if (field == FieldYear) return "musicvideo_view.premiered";
+    else if (field == FieldPlot) result = StringUtils::Format("musicvideo_view.c%02d", VIDEODB_ID_MUSICVIDEO_PLOT);
+    else if (field == FieldAlbum) result = StringUtils::Format("musicvideo_view.c%02d",VIDEODB_ID_MUSICVIDEO_ALBUM);
+    else if (field == FieldArtist) result = StringUtils::Format("musicvideo_view.c%02d", VIDEODB_ID_MUSICVIDEO_ARTIST);
+    else if (field == FieldGenre) result = StringUtils::Format("musicvideo_view.c%02d", VIDEODB_ID_MUSICVIDEO_GENRE);
+    else if (field == FieldTrackNumber) result = StringUtils::Format("musicvideo_view.c%02d", VIDEODB_ID_MUSICVIDEO_TRACK);
+    else if (field == FieldFilename) return "musicvideo_view.strFilename";
+    else if (field == FieldPath) return "musicvideo_view.strPath";
+    else if (field == FieldPlaycount) return "musicvideo_view.playCount";
+    else if (field == FieldLastPlayed) return "musicvideo_view.lastPlayed";
+    else if (field == FieldDateAdded) return "musicvideo_view.dateAdded";
+    else if (field == FieldUserRating) return "musicvideo_view.userrating";
+
+    if (!result.empty())
+      return result;
+  }
+  else if (mediaType == MediaTypeMovie)
+  {
+    std::string result;
+    if (field == FieldId) return "movie_view.idMovie";
+    else if (field == FieldTitle)
+    {
+      // We need some extra logic to get the title value if sorttitle isn't set
+      if (queryPart == DatabaseQueryPartOrderBy)
+        result = StringUtils::Format("CASE WHEN length(movie_view.c%02d) > 0 THEN movie_view.c%02d ELSE movie_view.c%02d END", VIDEODB_ID_SORTTITLE, VIDEODB_ID_SORTTITLE, VIDEODB_ID_TITLE);
+      else
+        result = StringUtils::Format("movie_view.c%02d", VIDEODB_ID_TITLE);
+    }
+    else if (field == FieldPlot) result = StringUtils::Format("movie_view.c%02d", VIDEODB_ID_PLOT);
+    else if (field == FieldPlotOutline) result = StringUtils::Format("movie_view.c%02d", VIDEODB_ID_PLOTOUTLINE);
+    else if (field == FieldTagline) result = StringUtils::Format("movie_view.c%02d", VIDEODB_ID_TAGLINE);
+    else if (field == FieldVotes) return "movie_view.votes";
+    else if (field == FieldRating) return "movie_view.rating";
+    else if (field == FieldWriter) result = StringUtils::Format("movie_view.c%02d", VIDEODB_ID_CREDITS);
+    else if (field == FieldYear) return "movie_view.premiered";
+    else if (field == FieldSortTitle) result = StringUtils::Format("movie_view.c%02d", VIDEODB_ID_SORTTITLE);
+    else if (field == FieldOriginalTitle) result = StringUtils::Format("movie_view.c%02d", VIDEODB_ID_ORIGINALTITLE);
+    else if (field == FieldTime) result = StringUtils::Format("movie_view.c%02d", VIDEODB_ID_RUNTIME);
+    else if (field == FieldMPAA) result = StringUtils::Format("movie_view.c%02d", VIDEODB_ID_MPAA);
+    else if (field == FieldTop250) result = StringUtils::Format("movie_view.c%02d", VIDEODB_ID_TOP250);
+    else if (field == FieldSet) return "movie_view.strSet";
+    else if (field == FieldGenre) result = StringUtils::Format("movie_view.c%02d", VIDEODB_ID_GENRE);
+    else if (field == FieldDirector) result = StringUtils::Format("movie_view.c%02d", VIDEODB_ID_DIRECTOR);
+    else if (field == FieldStudio) result = StringUtils::Format("movie_view.c%02d", VIDEODB_ID_STUDIOS);
+    else if (field == FieldTrailer) result = StringUtils::Format("movie_view.c%02d", VIDEODB_ID_TRAILER);
+    else if (field == FieldCountry) result = StringUtils::Format("movie_view.c%02d", VIDEODB_ID_COUNTRY);
+    else if (field == FieldFilename) return "movie_view.strFilename";
+    else if (field == FieldPath) return "movie_view.strPath";
+    else if (field == FieldPlaycount) return "movie_view.playCount";
+    else if (field == FieldLastPlayed) return "movie_view.lastPlayed";
+    else if (field == FieldDateAdded) return "movie_view.dateAdded";
+    else if (field == FieldUserRating) return "movie_view.userrating";
+
+    if (!result.empty())
+      return result;
+  }
+  else if (mediaType == MediaTypeTvShow)
+  {
+    std::string result;
+    if (field == FieldId) return "tvshow_view.idShow";
+    else if (field == FieldTitle)
+    {
+      // We need some extra logic to get the title value if sorttitle isn't set
+      if (queryPart == DatabaseQueryPartOrderBy)
+        result = StringUtils::Format("CASE WHEN length(tvshow_view.c%02d) > 0 THEN tvshow_view.c%02d ELSE tvshow_view.c%02d END", VIDEODB_ID_TV_SORTTITLE, VIDEODB_ID_TV_SORTTITLE, VIDEODB_ID_TV_TITLE);
+      else
+        result = StringUtils::Format("tvshow_view.c%02d", VIDEODB_ID_TV_TITLE);
+    }
+    else if (field == FieldPlot) result = StringUtils::Format("tvshow_view.c%02d", VIDEODB_ID_TV_PLOT);
+    else if (field == FieldTvShowStatus) result = StringUtils::Format("tvshow_view.c%02d", VIDEODB_ID_TV_STATUS);
+    else if (field == FieldVotes) return "tvshow_view.votes";
+    else if (field == FieldRating) return "tvshow_view.rating";
+    else if (field == FieldYear) result = StringUtils::Format("tvshow_view.c%02d", VIDEODB_ID_TV_PREMIERED);
+    else if (field == FieldGenre) result = StringUtils::Format("tvshow_view.c%02d", VIDEODB_ID_TV_GENRE);
+    else if (field == FieldMPAA) result = StringUtils::Format("tvshow_view.c%02d", VIDEODB_ID_TV_MPAA);
+    else if (field == FieldStudio) result = StringUtils::Format("tvshow_view.c%02d", VIDEODB_ID_TV_STUDIOS);
+    else if (field == FieldSortTitle) result = StringUtils::Format("tvshow_view.c%02d", VIDEODB_ID_TV_SORTTITLE);
+    else if (field == FieldOriginalTitle) result = StringUtils::Format("tvshow_view.c%02d", VIDEODB_ID_TV_ORIGINALTITLE);
+    else if (field == FieldPath) return "tvshow_view.strPath";
+    else if (field == FieldDateAdded) return "tvshow_view.dateAdded";
+    else if (field == FieldLastPlayed) return "tvshow_view.lastPlayed";
+    else if (field == FieldSeason) return "tvshow_view.totalSeasons";
+    else if (field == FieldNumberOfEpisodes) return "tvshow_view.totalCount";
+    else if (field == FieldNumberOfWatchedEpisodes) return "tvshow_view.watchedcount";
+    else if (field == FieldUserRating) return "tvshow_view.userrating";
+
+    if (!result.empty())
+      return result;
+  }
+  else if (mediaType == MediaTypeEpisode)
+  {
+    std::string result;
+    if (field == FieldId) return "episode_view.idEpisode";
+    else if (field == FieldTitle) result = StringUtils::Format("episode_view.c%02d", VIDEODB_ID_EPISODE_TITLE);
+    else if (field == FieldPlot) result = StringUtils::Format("episode_view.c%02d", VIDEODB_ID_EPISODE_PLOT);
+    else if (field == FieldVotes) return "episode_view.votes";
+    else if (field == FieldRating) return "episode_view.rating";
+    else if (field == FieldWriter) result = StringUtils::Format("episode_view.c%02d", VIDEODB_ID_EPISODE_CREDITS);
+    else if (field == FieldAirDate) result = StringUtils::Format("episode_view.c%02d", VIDEODB_ID_EPISODE_AIRED);
+    else if (field == FieldTime) result = StringUtils::Format("episode_view.c%02d", VIDEODB_ID_EPISODE_RUNTIME);
+    else if (field == FieldDirector) result = StringUtils::Format("episode_view.c%02d", VIDEODB_ID_EPISODE_DIRECTOR);
+    else if (field == FieldSeason) result = StringUtils::Format("episode_view.c%02d", VIDEODB_ID_EPISODE_SEASON);
+    else if (field == FieldEpisodeNumber) result = StringUtils::Format("episode_view.c%02d", VIDEODB_ID_EPISODE_EPISODE);
+    else if (field == FieldUniqueId) result = StringUtils::Format("episode_view.c%02d", VIDEODB_ID_EPISODE_IDENT_ID);
+    else if (field == FieldEpisodeNumberSpecialSort) result = StringUtils::Format("episode_view.c%02d", VIDEODB_ID_EPISODE_SORTEPISODE);
+    else if (field == FieldSeasonSpecialSort) result = StringUtils::Format("episode_view.c%02d", VIDEODB_ID_EPISODE_SORTSEASON);
+    else if (field == FieldFilename) return "episode_view.strFilename";
+    else if (field == FieldPath) return "episode_view.strPath";
+    else if (field == FieldPlaycount) return "episode_view.playCount";
+    else if (field == FieldLastPlayed) return "episode_view.lastPlayed";
+    else if (field == FieldDateAdded) return "episode_view.dateAdded";
+    else if (field == FieldTvShowTitle) return "episode_view.strTitle";
+    else if (field == FieldYear) return "episode_view.premiered";
+    else if (field == FieldMPAA) return "episode_view.mpaa";
+    else if (field == FieldStudio) return "episode_view.strStudio";
+    else if (field == FieldUserRating) return "episode_view.userrating";
+
+    if (!result.empty())
+      return result;
+  }
+
+  if (field == FieldRandom && queryPart == DatabaseQueryPartOrderBy)
+    return "RANDOM()";
+
+  return "";
+}
+
+int DatabaseUtils::GetField(Field field, const MediaType &mediaType)
+{
+  if (field == FieldNone || mediaType == MediaTypeNone)
+    return -1;
+
+  return GetField(field, mediaType, false);
+}
+
+int DatabaseUtils::GetFieldIndex(Field field, const MediaType &mediaType)
+{
+  if (field == FieldNone || mediaType == MediaTypeNone)
+    return -1;
+
+  return GetField(field, mediaType, true);
+}
+
+bool DatabaseUtils::GetSelectFields(const Fields &fields, const MediaType &mediaType, FieldList &selectFields)
+{
+  if (mediaType == MediaTypeNone || fields.empty())
+    return false;
+
+  Fields sortFields = fields;
+
+  // add necessary fields to create the label
+  if (mediaType == MediaTypeSong || mediaType == MediaTypeVideo || mediaType == MediaTypeVideoCollection ||
+      mediaType == MediaTypeMusicVideo || mediaType == MediaTypeMovie || mediaType == MediaTypeTvShow || mediaType == MediaTypeEpisode)
+    sortFields.insert(FieldTitle);
+  if (mediaType == MediaTypeEpisode)
+  {
+    sortFields.insert(FieldSeason);
+    sortFields.insert(FieldEpisodeNumber);
+  }
+  else if (mediaType == MediaTypeAlbum)
+    sortFields.insert(FieldAlbum);
+  else if (mediaType == MediaTypeSong)
+    sortFields.insert(FieldTrackNumber);
+  else if (mediaType == MediaTypeArtist)
+    sortFields.insert(FieldArtist);
+
+  selectFields.clear();
+  for (Fields::const_iterator it = sortFields.begin(); it != sortFields.end(); ++it)
+  {
+    // ignore FieldLabel because it needs special handling (see further up)
+    if (*it == FieldLabel)
+      continue;
+
+    if (GetField(*it, mediaType, DatabaseQueryPartSelect).empty())
+    {
+      CLog::Log(LOGDEBUG, "DatabaseUtils::GetSortFieldList: unknown field %d", *it);
+      continue;
+    }
+    selectFields.push_back(*it);
+  }
+
+  return !selectFields.empty();
+}
+
+bool DatabaseUtils::GetFieldValue(const dbiplus::field_value &fieldValue, CVariant &variantValue)
+{
+  if (fieldValue.get_isNull())
+  {
+    variantValue = CVariant::ConstNullVariant;
+    return true;
+  }
+
+  switch (fieldValue.get_fType())
+  {
+  case dbiplus::ft_String:
+  case dbiplus::ft_WideString:
+  case dbiplus::ft_Object:
+    variantValue = fieldValue.get_asString();
+    return true;
+  case dbiplus::ft_Char:
+  case dbiplus::ft_WChar:
+    variantValue = fieldValue.get_asChar();
+    return true;
+  case dbiplus::ft_Boolean:
+    variantValue = fieldValue.get_asBool();
+    return true;
+  case dbiplus::ft_Short:
+    variantValue = fieldValue.get_asShort();
+    return true;
+  case dbiplus::ft_UShort:
+    variantValue = fieldValue.get_asShort();
+    return true;
+  case dbiplus::ft_Int:
+    variantValue = fieldValue.get_asInt();
+    return true;
+  case dbiplus::ft_UInt:
+    variantValue = fieldValue.get_asUInt();
+    return true;
+  case dbiplus::ft_Float:
+    variantValue = fieldValue.get_asFloat();
+    return true;
+  case dbiplus::ft_Double:
+  case dbiplus::ft_LongDouble:
+    variantValue = fieldValue.get_asDouble();
+    return true;
+  case dbiplus::ft_Int64:
+    variantValue = fieldValue.get_asInt64();
+    return true;
+  }
+
+  return false;
+}
+
+bool DatabaseUtils::GetDatabaseResults(const MediaType &mediaType, const FieldList &fields, const std::unique_ptr<dbiplus::Dataset> &dataset, DatabaseResults &results)
+{
+  if (dataset->num_rows() == 0)
+    return true;
+
+  const dbiplus::result_set &resultSet = dataset->get_result_set();
+  unsigned int offset = results.size();
+
+  if (fields.empty())
+  {
+    DatabaseResult result;
+    for (unsigned int index = 0; index < resultSet.records.size(); index++)
+    {
+      result[FieldRow] = index + offset;
+      results.push_back(result);
+    }
+
+    return true;
+  }
+
+  if (resultSet.record_header.size() < fields.size())
+    return false;
+
+  std::vector<int> fieldIndexLookup;
+  fieldIndexLookup.reserve(fields.size());
+  for (FieldList::const_iterator it = fields.begin(); it != fields.end(); ++it)
+    fieldIndexLookup.push_back(GetFieldIndex(*it, mediaType));
+
+  results.reserve(resultSet.records.size() + offset);
+  for (unsigned int index = 0; index < resultSet.records.size(); index++)
+  {
+    DatabaseResult result;
+    result[FieldRow] = index + offset;
+
+    unsigned int lookupIndex = 0;
+    for (FieldList::const_iterator it = fields.begin(); it != fields.end(); ++it)
+    {
+      int fieldIndex = fieldIndexLookup[lookupIndex++];
+      if (fieldIndex < 0)
+        return false;
+
+      std::pair<Field, CVariant> value;
+      value.first = *it;
+      if (!GetFieldValue(resultSet.records[index]->at(fieldIndex), value.second))
+        CLog::Log(LOGWARNING, "GetDatabaseResults: unable to retrieve value of field %s", resultSet.record_header[fieldIndex].name.c_str());
+
+      if (value.first == FieldYear &&
+         (mediaType == MediaTypeTvShow || mediaType == MediaTypeEpisode))
+      {
+        CDateTime dateTime;
+        dateTime.SetFromDBDate(value.second.asString());
+        if (dateTime.IsValid())
+        {
+          value.second.clear();
+          value.second = dateTime.GetYear();
+        }
+      }
+
+      result.insert(value);
+    }
+
+    result[FieldMediaType] = mediaType;
+    if (mediaType == MediaTypeMovie || mediaType == MediaTypeVideoCollection ||
+        mediaType == MediaTypeTvShow || mediaType == MediaTypeMusicVideo)
+      result[FieldLabel] = result.at(FieldTitle).asString();
+    else if (mediaType == MediaTypeEpisode)
+    {
+      std::ostringstream label;
+      label << (int)(result.at(FieldSeason).asInteger() * 100 + result.at(FieldEpisodeNumber).asInteger());
+      label << ". ";
+      label << result.at(FieldTitle).asString();
+      result[FieldLabel] = label.str();
+    }
+    else if (mediaType == MediaTypeAlbum)
+      result[FieldLabel] = result.at(FieldAlbum).asString();
+    else if (mediaType == MediaTypeSong)
+    {
+      std::ostringstream label;
+      label << (int)result.at(FieldTrackNumber).asInteger();
+      label << ". ";
+      label << result.at(FieldTitle).asString();
+      result[FieldLabel] = label.str();
+    }
+    else if (mediaType == MediaTypeArtist)
+      result[FieldLabel] = result.at(FieldArtist).asString();
+
+    results.push_back(result);
+  }
+
+  return true;
+}
+
+std::string DatabaseUtils::BuildLimitClause(int end, int start /* = 0 */)
+{
+  return " LIMIT " + BuildLimitClauseOnly(end, start);
+}
+
+std::string DatabaseUtils::BuildLimitClauseOnly(int end, int start /* = 0 */)
+{
+  std::ostringstream sql;
+  if (start > 0)
+  {
+    if (end > 0)
+    {
+      end = end - start;
+      if (end < 0)
+        end = 0;
+    }
+
+    sql << start << "," << end;
+  }
+  else
+    sql << end;
+
+  return sql.str();
+}
+
+size_t DatabaseUtils::GetLimitCount(int end, int start)
+{
+  if (start > 0)
+  {
+    if (end - start < 0)
+      return 0;
+    else
+      return static_cast<size_t>(end - start);
+  }
+  else if (end > 0)
+    return static_cast<size_t>(end);
+  return 0;
+}
+
+int DatabaseUtils::GetField(Field field, const MediaType &mediaType, bool asIndex)
+{
+  if (field == FieldNone || mediaType == MediaTypeNone)
+    return -1;
+
+  int index = -1;
+
+  if (mediaType == MediaTypeAlbum)
+  {
+    if (field == FieldId) return CMusicDatabase::album_idAlbum;
+    else if (field == FieldAlbum) return CMusicDatabase::album_strAlbum;
+    else if (field == FieldArtist || field == FieldAlbumArtist) return CMusicDatabase::album_strArtists;
+    else if (field == FieldGenre) return CMusicDatabase::album_strGenres;
+    else if (field == FieldYear) return CMusicDatabase::album_strReleaseDate;
+    else if (field == FieldMoods) return CMusicDatabase::album_strMoods;
+    else if (field == FieldStyles) return CMusicDatabase::album_strStyles;
+    else if (field == FieldThemes) return CMusicDatabase::album_strThemes;
+    else if (field == FieldReview) return CMusicDatabase::album_strReview;
+    else if (field == FieldMusicLabel) return CMusicDatabase::album_strLabel;
+    else if (field == FieldAlbumType) return CMusicDatabase::album_strType;
+    else if (field == FieldRating) return CMusicDatabase::album_fRating;
+    else if (field == FieldVotes) return CMusicDatabase::album_iVotes;
+    else if (field == FieldUserRating) return CMusicDatabase::album_iUserrating;
+    else if (field == FieldPlaycount) return CMusicDatabase::album_iTimesPlayed;
+    else if (field == FieldLastPlayed) return CMusicDatabase::album_dtLastPlayed;
+    else if (field == FieldDateAdded) return CMusicDatabase::album_dateAdded;
+    else if (field == FieldDateNew) return CMusicDatabase::album_dateNew;
+    else if (field == FieldDateModified) return CMusicDatabase::album_dateModified;
+    else if (field == FieldTotalDiscs)
+      return CMusicDatabase::album_iTotalDiscs;
+    else if (field == FieldOrigYear || field == FieldOrigDate)
+      return CMusicDatabase::album_strOrigReleaseDate;
+    else if (field == FieldAlbumStatus)
+      return CMusicDatabase::album_strReleaseStatus;
+  }
+  else if (mediaType == MediaTypeSong)
+  {
+    if (field == FieldId) return CMusicDatabase::song_idSong;
+    else if (field == FieldTitle) return CMusicDatabase::song_strTitle;
+    else if (field == FieldTrackNumber) return CMusicDatabase::song_iTrack;
+    else if (field == FieldTime) return CMusicDatabase::song_iDuration;
+    else if (field == FieldYear) return CMusicDatabase::song_strReleaseDate;
+    else if (field == FieldFilename) return CMusicDatabase::song_strFileName;
+    else if (field == FieldPlaycount) return CMusicDatabase::song_iTimesPlayed;
+    else if (field == FieldStartOffset) return CMusicDatabase::song_iStartOffset;
+    else if (field == FieldEndOffset) return CMusicDatabase::song_iEndOffset;
+    else if (field == FieldLastPlayed) return CMusicDatabase::song_lastplayed;
+    else if (field == FieldRating) return CMusicDatabase::song_rating;
+    else if (field == FieldUserRating) return CMusicDatabase::song_userrating;
+    else if (field == FieldVotes) return CMusicDatabase::song_votes;
+    else if (field == FieldComment) return CMusicDatabase::song_comment;
+    else if (field == FieldMoods) return CMusicDatabase::song_mood;
+    else if (field == FieldAlbum) return CMusicDatabase::song_strAlbum;
+    else if (field == FieldPath) return CMusicDatabase::song_strPath;
+    else if (field == FieldGenre) return CMusicDatabase::song_strGenres;
+    else if (field == FieldArtist || field == FieldAlbumArtist) return CMusicDatabase::song_strArtists;
+    else if (field == FieldDateAdded) return CMusicDatabase::song_dateAdded;
+    else if (field == FieldDateNew) return CMusicDatabase::song_dateNew;
+    else if (field == FieldDateModified) return CMusicDatabase::song_dateModified;
+    else if (field == FieldBPM)
+      return CMusicDatabase::song_iBPM;
+    else if (field == FieldMusicBitRate)
+        return CMusicDatabase::song_iBitRate;
+    else if (field == FieldSampleRate)
+        return CMusicDatabase::song_iSampleRate;
+    else if (field == FieldNoOfChannels)
+        return CMusicDatabase::song_iChannels;
+  }
+  else if (mediaType == MediaTypeArtist)
+  {
+    if (field == FieldId) return CMusicDatabase::artist_idArtist;
+    else if (field == FieldArtist) return CMusicDatabase::artist_strArtist;
+    else if (field == FieldArtistSort) return CMusicDatabase::artist_strSortName;
+    else if (field == FieldArtistType) return CMusicDatabase::artist_strType;
+    else if (field == FieldGender) return CMusicDatabase::artist_strGender;
+    else if (field == FieldDisambiguation) return CMusicDatabase::artist_strDisambiguation;
+    else if (field == FieldGenre) return CMusicDatabase::artist_strGenres;
+    else if (field == FieldMoods) return CMusicDatabase::artist_strMoods;
+    else if (field == FieldStyles) return CMusicDatabase::artist_strStyles;
+    else if (field == FieldInstruments) return CMusicDatabase::artist_strInstruments;
+    else if (field == FieldBiography) return CMusicDatabase::artist_strBiography;
+    else if (field == FieldBorn) return CMusicDatabase::artist_strBorn;
+    else if (field == FieldBandFormed) return CMusicDatabase::artist_strFormed;
+    else if (field == FieldDisbanded) return CMusicDatabase::artist_strDisbanded;
+    else if (field == FieldDied) return CMusicDatabase::artist_strDied;
+    else if (field == FieldDateAdded) return CMusicDatabase::artist_dateAdded;
+    else if (field == FieldDateNew) return CMusicDatabase::artist_dateNew;
+    else if (field == FieldDateModified) return CMusicDatabase::artist_dateModified;
+  }
+  else if (mediaType == MediaTypeMusicVideo)
+  {
+    if (field == FieldId) return 0;
+    else if (field == FieldTitle) index = VIDEODB_ID_MUSICVIDEO_TITLE;
+    else if (field == FieldTime) index =  VIDEODB_ID_MUSICVIDEO_RUNTIME;
+    else if (field == FieldDirector) index =  VIDEODB_ID_MUSICVIDEO_DIRECTOR;
+    else if (field == FieldStudio) index =  VIDEODB_ID_MUSICVIDEO_STUDIOS;
+    else if (field == FieldYear) return VIDEODB_DETAILS_MUSICVIDEO_PREMIERED;
+    else if (field == FieldPlot) index =  VIDEODB_ID_MUSICVIDEO_PLOT;
+    else if (field == FieldAlbum) index = VIDEODB_ID_MUSICVIDEO_ALBUM;
+    else if (field == FieldArtist) index =  VIDEODB_ID_MUSICVIDEO_ARTIST;
+    else if (field == FieldGenre) index =  VIDEODB_ID_MUSICVIDEO_GENRE;
+    else if (field == FieldTrackNumber) index =  VIDEODB_ID_MUSICVIDEO_TRACK;
+    else if (field == FieldFilename) return VIDEODB_DETAILS_MUSICVIDEO_FILE;
+    else if (field == FieldPath) return VIDEODB_DETAILS_MUSICVIDEO_PATH;
+    else if (field == FieldPlaycount) return VIDEODB_DETAILS_MUSICVIDEO_PLAYCOUNT;
+    else if (field == FieldLastPlayed) return VIDEODB_DETAILS_MUSICVIDEO_LASTPLAYED;
+    else if (field == FieldDateAdded) return VIDEODB_DETAILS_MUSICVIDEO_DATEADDED;
+    else if (field == FieldUserRating) return VIDEODB_DETAILS_MUSICVIDEO_USER_RATING;
+
+    if (index < 0)
+      return index;
+
+    if (asIndex)
+    {
+      // see VideoDatabase.h
+      // the first field is the item's ID and the second is the item's file ID
+      index += 2;
+    }
+  }
+  else if (mediaType == MediaTypeMovie)
+  {
+    if (field == FieldId) return 0;
+    else if (field == FieldTitle) index = VIDEODB_ID_TITLE;
+    else if (field == FieldSortTitle) index = VIDEODB_ID_SORTTITLE;
+    else if (field == FieldOriginalTitle) index = VIDEODB_ID_ORIGINALTITLE;
+    else if (field == FieldPlot) index = VIDEODB_ID_PLOT;
+    else if (field == FieldPlotOutline) index = VIDEODB_ID_PLOTOUTLINE;
+    else if (field == FieldTagline) index = VIDEODB_ID_TAGLINE;
+    else if (field == FieldVotes) return VIDEODB_DETAILS_MOVIE_VOTES;
+    else if (field == FieldRating) return VIDEODB_DETAILS_MOVIE_RATING;
+    else if (field == FieldWriter) index = VIDEODB_ID_CREDITS;
+    else if (field == FieldYear) return VIDEODB_DETAILS_MOVIE_PREMIERED;
+    else if (field == FieldTime) index = VIDEODB_ID_RUNTIME;
+    else if (field == FieldMPAA) index = VIDEODB_ID_MPAA;
+    else if (field == FieldTop250) index = VIDEODB_ID_TOP250;
+    else if (field == FieldSet) return VIDEODB_DETAILS_MOVIE_SET_NAME;
+    else if (field == FieldGenre) index = VIDEODB_ID_GENRE;
+    else if (field == FieldDirector) index = VIDEODB_ID_DIRECTOR;
+    else if (field == FieldStudio) index = VIDEODB_ID_STUDIOS;
+    else if (field == FieldTrailer) index = VIDEODB_ID_TRAILER;
+    else if (field == FieldCountry) index = VIDEODB_ID_COUNTRY;
+    else if (field == FieldFilename) index = VIDEODB_DETAILS_MOVIE_FILE;
+    else if (field == FieldPath) return VIDEODB_DETAILS_MOVIE_PATH;
+    else if (field == FieldPlaycount) return VIDEODB_DETAILS_MOVIE_PLAYCOUNT;
+    else if (field == FieldLastPlayed) return VIDEODB_DETAILS_MOVIE_LASTPLAYED;
+    else if (field == FieldDateAdded) return VIDEODB_DETAILS_MOVIE_DATEADDED;
+    else if (field == FieldUserRating) return VIDEODB_DETAILS_MOVIE_USER_RATING;
+
+    if (index < 0)
+      return index;
+
+    if (asIndex)
+    {
+      // see VideoDatabase.h
+      // the first field is the item's ID and the second is the item's file ID
+      index += 2;
+    }
+  }
+  else if (mediaType == MediaTypeTvShow)
+  {
+    if (field == FieldId) return 0;
+    else if (field == FieldTitle) index = VIDEODB_ID_TV_TITLE;
+    else if (field == FieldSortTitle) index = VIDEODB_ID_TV_SORTTITLE;
+    else if (field == FieldOriginalTitle) index = VIDEODB_ID_TV_ORIGINALTITLE;
+    else if (field == FieldPlot) index = VIDEODB_ID_TV_PLOT;
+    else if (field == FieldTvShowStatus) index = VIDEODB_ID_TV_STATUS;
+    else if (field == FieldVotes) return VIDEODB_DETAILS_TVSHOW_VOTES;
+    else if (field == FieldRating) return VIDEODB_DETAILS_TVSHOW_RATING;
+    else if (field == FieldYear) index = VIDEODB_ID_TV_PREMIERED;
+    else if (field == FieldGenre) index = VIDEODB_ID_TV_GENRE;
+    else if (field == FieldMPAA) index = VIDEODB_ID_TV_MPAA;
+    else if (field == FieldStudio) index = VIDEODB_ID_TV_STUDIOS;
+    else if (field == FieldPath) return VIDEODB_DETAILS_TVSHOW_PATH;
+    else if (field == FieldDateAdded) return VIDEODB_DETAILS_TVSHOW_DATEADDED;
+    else if (field == FieldLastPlayed) return VIDEODB_DETAILS_TVSHOW_LASTPLAYED;
+    else if (field == FieldNumberOfEpisodes) return VIDEODB_DETAILS_TVSHOW_NUM_EPISODES;
+    else if (field == FieldNumberOfWatchedEpisodes) return VIDEODB_DETAILS_TVSHOW_NUM_WATCHED;
+    else if (field == FieldSeason) return VIDEODB_DETAILS_TVSHOW_NUM_SEASONS;
+    else if (field == FieldUserRating) return VIDEODB_DETAILS_TVSHOW_USER_RATING;
+
+    if (index < 0)
+      return index;
+
+    if (asIndex)
+    {
+      // see VideoDatabase.h
+      // the first field is the item's ID
+      index += 1;
+    }
+  }
+  else if (mediaType == MediaTypeEpisode)
+  {
+    if (field == FieldId) return 0;
+    else if (field == FieldTitle) index = VIDEODB_ID_EPISODE_TITLE;
+    else if (field == FieldPlot) index = VIDEODB_ID_EPISODE_PLOT;
+    else if (field == FieldVotes) return VIDEODB_DETAILS_EPISODE_VOTES;
+    else if (field == FieldRating) return VIDEODB_DETAILS_EPISODE_RATING;
+    else if (field == FieldWriter) index = VIDEODB_ID_EPISODE_CREDITS;
+    else if (field == FieldAirDate) index = VIDEODB_ID_EPISODE_AIRED;
+    else if (field == FieldTime) index = VIDEODB_ID_EPISODE_RUNTIME;
+    else if (field == FieldDirector) index = VIDEODB_ID_EPISODE_DIRECTOR;
+    else if (field == FieldSeason) index = VIDEODB_ID_EPISODE_SEASON;
+    else if (field == FieldEpisodeNumber) index = VIDEODB_ID_EPISODE_EPISODE;
+    else if (field == FieldUniqueId) index = VIDEODB_ID_EPISODE_IDENT_ID;
+    else if (field == FieldEpisodeNumberSpecialSort) index = VIDEODB_ID_EPISODE_SORTEPISODE;
+    else if (field == FieldSeasonSpecialSort) index = VIDEODB_ID_EPISODE_SORTSEASON;
+    else if (field == FieldFilename) return VIDEODB_DETAILS_EPISODE_FILE;
+    else if (field == FieldPath) return VIDEODB_DETAILS_EPISODE_PATH;
+    else if (field == FieldPlaycount) return VIDEODB_DETAILS_EPISODE_PLAYCOUNT;
+    else if (field == FieldLastPlayed) return VIDEODB_DETAILS_EPISODE_LASTPLAYED;
+    else if (field == FieldDateAdded) return VIDEODB_DETAILS_EPISODE_DATEADDED;
+    else if (field == FieldTvShowTitle) return VIDEODB_DETAILS_EPISODE_TVSHOW_NAME;
+    else if (field == FieldStudio) return VIDEODB_DETAILS_EPISODE_TVSHOW_STUDIO;
+    else if (field == FieldYear) return VIDEODB_DETAILS_EPISODE_TVSHOW_AIRED;
+    else if (field == FieldMPAA) return VIDEODB_DETAILS_EPISODE_TVSHOW_MPAA;
+    else if (field == FieldUserRating) return VIDEODB_DETAILS_EPISODE_USER_RATING;
+
+    if (index < 0)
+      return index;
+
+    if (asIndex)
+    {
+      // see VideoDatabase.h
+      // the first field is the item's ID and the second is the item's file ID
+      index += 2;
+    }
+  }
+
+  return index;
+}