Add support of decimal type

CHANGELOG.md

@@ -1,3 +1,4 @@
+- Add support of decimal type
 ## v0.0.9
 - Remove support for .NET Core 3.1
 - Add support for .NET 7.0

src/Ydb.Sdk/src/Value/YdbValueBuilder.cs

@@ -11,6 +11,7 @@ public static YdbValue MakeBool(bool value)
                     BoolValue = value
                 });
         }
+
         public static YdbValue MakeInt8(sbyte value)
         {
             return new YdbValue(
@@ -201,12 +202,115 @@ public static YdbValue MakeJsonDocument(string value)
                 });
         }
 
+        private static byte GetDecimalScale(decimal value)
+        {
+            var bits = decimal.GetBits(value);
+            var flags = bits[3];
+            var scale = (byte)((flags >> 16) & 0x7F);
+            return scale;
+        }
+
+        private static uint GetDecimalPrecision(decimal value)
+        {
+            var bits = decimal.GetBits(value);
+            value = new decimal(lo: bits[0], mid: bits[1], hi: bits[2], isNegative: false, scale: 0);
+
+            var precision = 0u;
+            while (value != decimal.Zero)
+            {
+                value = Math.Round(value / 10);
+                precision++;
+            }
+
+            return precision;
+        }
+
+        private static Ydb.Value MakeDecimalValue(decimal value)
+        {
+            var bits = decimal.GetBits(value);
+
+            var low64 = ((ulong)(uint)bits[1] << 32) + (uint)bits[0];
+            var high64 = (ulong)(uint)bits[2];
+
+            unchecked
+            {
+                // make value negative
+                if (value < 0)
+                {
+                    low64 = ~low64;
+                    high64 = ~high64;
+
+                    if (low64 == (ulong)-1L)
+                    {
+                        high64 += 1;
+                    }
+
+                    low64 += 1;
+                }
+            }
+
+            return new Ydb.Value
+            {
+                Low128 = low64,
+                High128 = high64
+            };
+        }
+
+        public static YdbValue MakeDecimalWithPrecision(decimal value, uint? precision = null, uint? scale = null)
+        {
+            var valueScale = GetDecimalScale(value);
+            var valuePrecision = GetDecimalPrecision(value);
+            scale ??= GetDecimalScale(value);
+            precision ??= valuePrecision;
+
+            if ((int)valuePrecision - valueScale > (int)precision - scale)
+            {
+                throw new InvalidCastException(
+                    $"Decimal with precision ({valuePrecision}, {valueScale}) can't fit into ({precision}, {scale})");
+            }
+
+            // multiply for fill value with trailing zeros
+            // ex: 123.45 -> 123.4500...00
+            value *= 1.00000000000000000000000000000m; // 29 zeros, max supported by c# decimal
+            value = Math.Round(value, (int)scale);
+
+            var type = new Type
+            {
+                DecimalType = new DecimalType { Scale = (uint)scale, Precision = (uint)precision }
+            };
+
+            var ydbValue = MakeDecimalValue(value);
+
+            return new YdbValue(type, ydbValue);
+        }
+
+        public static YdbValue MakeDecimal(decimal value)
+        {
+            return MakeDecimalWithPrecision(value, 22, 9);
+        }
+
         // TODO: EmptyOptional with complex types
         public static YdbValue MakeEmptyOptional(YdbTypeId typeId)
         {
-            return new YdbValue(
-                new Ydb.Type { OptionalType = new OptionalType { Item = MakePrimitiveType(typeId) } },
-                new Ydb.Value { NullFlagValue = new Google.Protobuf.WellKnownTypes.NullValue() });
+            if (IsPrimitiveTypeId(typeId))
+            {
+                return new YdbValue(
+                    new Type { OptionalType = new OptionalType { Item = MakePrimitiveType(typeId) } },
+                    new Ydb.Value { NullFlagValue = new Google.Protobuf.WellKnownTypes.NullValue() });
+            }
+
+            if (typeId == YdbTypeId.DecimalType)
+            {
+                return new YdbValue(
+                    new Type
+                    {
+                        OptionalType = new OptionalType { Item = new Type { DecimalType = new DecimalType() } }
+                    },
+                    new Ydb.Value { NullFlagValue = new Google.Protobuf.WellKnownTypes.NullValue() }
+                );
+            }
+
+            throw new ArgumentException($"This type is not supported: {typeId}", nameof(typeId));
         }
 
         public static YdbValue MakeOptional(YdbValue value)
@@ -266,7 +370,8 @@ public static YdbValue MakeStruct(IReadOnlyDictionary<string, YdbValue> members)
                 StructType = new StructType()
             };
 
-            type.StructType.Members.Add(members.Select(m => new StructMember { Name = m.Key, Type = m.Value._protoType }));
+            type.StructType.Members.Add(
+                members.Select(m => new StructMember { Name = m.Key, Type = m.Value._protoType }));
 
             var value = new Ydb.Value();
             value.Items.Add(members.Select(m => m.Value._protoValue));
@@ -287,9 +392,14 @@ private static Ydb.Type MakePrimitiveType(YdbTypeId typeId)
             return new Ydb.Type { TypeId = (Type.Types.PrimitiveTypeId)typeId };
         }
 
+        private static bool IsPrimitiveTypeId(YdbTypeId typeId)
+        {
+            return (uint)typeId < YdbTypeIdRanges.ComplexTypesFirst;
+        }
+
         private static void EnsurePrimitiveTypeId(YdbTypeId typeId)
         {
-            if ((uint)typeId >= YdbTypeIdRanges.ComplexTypesFirst)
+            if (!IsPrimitiveTypeId(typeId))
             {
                 throw new ArgumentException($"Complex types aren't supported in current method: {typeId}", "typeId");
             }
@@ -442,5 +552,10 @@ public static YdbValue MakeOptionalJsonDocument(string? value)
                 return MakeOptional(MakeJsonDocument(value));
             }
         }
+
+        public static YdbValue MakeOptionalDecimal(decimal? value)
+        {
+            return MakeOptionalOf(value, YdbTypeId.DecimalType, MakeDecimal);
+        }
     }
-}
+}

src/Ydb.Sdk/src/Value/YdbValueCast.cs

@@ -8,10 +8,12 @@ public static explicit operator bool(YdbValue value)
         {
             return (bool)GetObject(value, typeof(bool));
         }
+
         public static explicit operator bool?(YdbValue value)
         {
             return (bool?)GetOptionalObject(value, typeof(bool));
         }
+
         public static explicit operator sbyte(YdbValue value)
         {
             return (sbyte)GetObject(value, typeof(sbyte));
@@ -142,6 +144,16 @@ public static explicit operator TimeSpan(YdbValue value)
             return (byte[]?)GetOptionalObject(value, typeof(byte[]));
         }
 
+        public static explicit operator decimal(YdbValue value)
+        {
+            return (decimal)GetObject(value, typeof(decimal));
+        }
+
+        public static explicit operator decimal?(YdbValue value)
+        {
+            return (decimal?)GetOptionalObject(value, typeof(decimal));
+        }
+
         private static object GetObject(YdbValue value, System.Type targetType)
         {
             return GetObjectInternal(value.TypeId, value, targetType);
@@ -179,6 +191,7 @@ private static object GetObject(YdbValue value, System.Type targetType)
                 case YdbTypeId.Yson: return value?.GetYson();
                 case YdbTypeId.Json: return value?.GetJson();
                 case YdbTypeId.JsonDocument: return value?.GetJsonDocument();
+                case YdbTypeId.DecimalType: return value?.GetDecimal();
                 default:
                     throw new InvalidCastException($"Cannot cast YDB type {typeId} to {targetType.Name}.");
 
@@ -304,5 +317,15 @@ public static explicit operator YdbValue(TimeSpan? value)
         {
             return MakeOptionalInterval(value);
         }
+
+        public static explicit operator YdbValue(decimal value)
+        {
+            return MakeDecimal(value);
+        }
+
+        public static explicit operator YdbValue(decimal? value)
+        {
+            return MakeOptionalDecimal(value);
+        }
     }
 }

src/Ydb.Sdk/src/Value/YdbValueParser.cs

@@ -127,6 +127,36 @@ public string GetJsonDocument()
             return _protoValue.TextValue;
         }
 
+        public decimal GetDecimal()
+        {
+            EnsureType(Type.TypeOneofCase.DecimalType);
+            var low64 = _protoValue.Low128;
+            var high64 = _protoValue.High128;
+
+            var scale = _protoType.DecimalType.Scale;
+
+            var isNegative = false;
+
+            unchecked
+            {
+                if (high64 >> 63 == 1) // if negative
+                {
+                    isNegative = true;
+                    if (low64 == 0)
+                    {
+                        high64 -= 1;
+                    }
+
+                    low64 -= 1;
+
+                    low64 = ~low64;
+                    high64 = ~high64;
+                }
+            }
+
+            return new decimal((int)low64, (int)(low64 >> 32), (int)high64, isNegative, (byte)scale);
+        }
+
         public bool? GetOptionalBool()
         {
             return GetOptional()?.GetBool();
@@ -228,6 +258,11 @@ public string GetJsonDocument()
             return GetOptional()?.GetJsonDocument();
         }
 
+        public decimal? GetOptionalDecimal()
+        {
+            return GetOptional()?.GetDecimal();
+        }
+
         public YdbValue? GetOptional()
         {
             EnsureType(Ydb.Type.TypeOneofCase.OptionalType);
@@ -288,4 +323,4 @@ internal InvalidTypeException(string expectedType, string actualType)
             }
         }
     }
-}
+}

src/Ydb.Sdk/tests/Value/TestBasicUnit.cs

@@ -256,6 +256,63 @@ public void OptionalPrimitiveCast()
             Assert.Null((TimeSpan?)(YdbValue)(TimeSpan?)null);
         }
 
+        [Fact]
+        public void DecimalType()
+        {
+            (decimal, decimal)[] values =
+            {
+                (-0.1m, -0.1m),
+                (0.0000000000000000000000000001m, 0m),
+                (0.0000000000000000000000000000m, 0m),
+                (-18446744073.709551616m,
+                    -18446744073.709551616m), // covers situation when need to add/substract 1 to/from high64
+                (123.456m, 123.456m),
+            };
+            foreach (var (value, excepted) in values)
+            {
+                var ydbval = YdbValue.MakeDecimal(value);
+                var result = ydbval.GetDecimal();
+                Assert.Equal(excepted, result);
+
+                Assert.Equal(excepted, YdbValue.MakeDecimal(value).GetDecimal());
+                Assert.Equal(excepted, YdbValue.MakeOptionalDecimal(value).GetOptionalDecimal());
+
+                Assert.Equal(excepted, (decimal)(YdbValue)value);
+                Assert.Equal(excepted, (decimal?)(YdbValue)(decimal?)value);
+            }
+
+            Assert.Null(YdbValue.MakeOptionalDecimal(null).GetOptionalDecimal());
+            Assert.Null((decimal?)(YdbValue)(decimal?)null);
+
+            Assert.Equal("Decimal with precision (30, 0) can't fit into (22, 9)",
+                Assert.Throws<InvalidCastException>(() => YdbValue.MakeDecimal(decimal.MaxValue)).Message);
+        }
+
+        [Fact]
+        public void DecimalTypeWithPrecision()
+        {
+            Assert.Equal(12345m, YdbValue.MakeDecimalWithPrecision(12345m).GetDecimal());
+            Assert.Equal(12345m, YdbValue.MakeDecimalWithPrecision(12345m, precision: 5, scale: 0).GetDecimal());
+            Assert.Equal(12345m, YdbValue.MakeDecimalWithPrecision(12345m, precision: 7, scale: 2).GetDecimal());
+            Assert.Equal(123.46m, YdbValue.MakeDecimalWithPrecision(123.456m, precision: 5, scale: 2).GetDecimal());
+            Assert.Equal(-18446744073.709551616m,
+                YdbValue.MakeDecimalWithPrecision(-18446744073.709551616m).GetDecimal());
+            Assert.Equal(-18446744073.709551616m,
+                YdbValue.MakeDecimalWithPrecision(-18446744073.709551616m, precision: 21, scale: 9).GetDecimal());
+            Assert.Equal(-18446744074m,
+                YdbValue.MakeDecimalWithPrecision(-18446744073.709551616m, precision: 12, scale: 0).GetDecimal());
+            Assert.Equal(-184467440730709551616m,
+                YdbValue.MakeDecimalWithPrecision(-184467440730709551616m, precision: 21, scale: 0).GetDecimal());
+
+
+            Assert.Equal("Decimal with precision (5, 0) can't fit into (4, 0)",
+                Assert.Throws<InvalidCastException>(() => YdbValue.MakeDecimalWithPrecision(12345m, precision: 4))
+                    .Message);
+            Assert.Equal("Decimal with precision (5, 0) can't fit into (5, 2)",
+                Assert.Throws<InvalidCastException>(() => YdbValue.MakeDecimalWithPrecision(12345m, precision: 5, 2))
+                    .Message);
+        }
+
         [Fact]
         public void ListType()
         {
@@ -306,4 +363,4 @@ public void StructType()
             Assert.Equal("ten", (string)s["Member2"]!);
         }
     }
-}
+}