| | | 1 | | namespace ZhEaIsNsAaBn.DbSeeder.Design; |
| | | 2 | | |
| | | 3 | | /// <summary> |
| | | 4 | | /// Orders row keys (canonical JSON values joined by <see cref="Separator"/>) part by part: <c>null</c> first, numbers b |
| | | 5 | | /// (<c>2</c> before <c>10</c>), everything else by ordinal text. Works the same on keys from the database and from file |
| | | 6 | | /// </summary> |
| | | 7 | | internal sealed class SeedKeyComparer : IComparer<string> |
| | | 8 | | { |
| | | 9 | | public const char Separator = '\u001F'; |
| | | 10 | | |
| | 3 | 11 | | public static readonly SeedKeyComparer Instance = new(); |
| | | 12 | | |
| | | 13 | | |
| | 2208 | 14 | | public static string Key( IEnumerable<string> jsonParts ) => string.Join( Separator, jsonParts ); |
| | | 15 | | |
| | | 16 | | public int Compare( string? x, string? y ) |
| | | 17 | | { |
| | 3030 | 18 | | var left = ( x ?? string.Empty ).Split( Separator ); |
| | 3030 | 19 | | var right = ( y ?? string.Empty ).Split( Separator ); |
| | | 20 | | |
| | 6060 | 21 | | for ( var i = 0; i < Math.Min( left.Length, right.Length ); i++ ) |
| | | 22 | | { |
| | 3030 | 23 | | var part = ComparePart( left[ i ], right[ i ] ); |
| | | 24 | | |
| | 6060 | 25 | | if ( part != 0 ) { return part; } |
| | | 26 | | } |
| | | 27 | | |
| | | 28 | | |
| | 0 | 29 | | return left.Length.CompareTo( right.Length ); |
| | | 30 | | } |
| | | 31 | | |
| | | 32 | | |
| | | 33 | | private static int ComparePart( string left, string right ) |
| | | 34 | | { |
| | 3030 | 35 | | if ( left == right ) { return 0; } |
| | | 36 | | |
| | 3030 | 37 | | if ( left == "null" || right == "null" ) { return left == "null" ? -1 : 1; } |
| | | 38 | | |
| | | 39 | | |
| | 3030 | 40 | | var numbers = decimal.TryParse( left, NumberStyles.Float, CultureInfo.InvariantCulture, out var a ) |
| | 3030 | 41 | | & decimal.TryParse( right, NumberStyles.Float, CultureInfo.InvariantCulture, out var b ); |
| | | 42 | | |
| | 3030 | 43 | | return numbers ? a.CompareTo( b ) : string.CompareOrdinal( left, right ); |
| | | 44 | | } |
| | | 45 | | } |