From 22d1d9d6208cb2aaf5c1fdfedda64d51d36146e3 Mon Sep 17 00:00:00 2001
From: Dmytro Kyshchenko <sys2712@gmail.com>
Date: Sun, 27 Mar 2022 09:51:12 +0300
Subject: [PATCH] #513 - Time Units

---
 xFunc.Maths/Parser.cs                    | 29 ++++++++++++++++-
 xFunc.Tests/ParserTests/TimeUnitTests.cs | 40 ++++++++++++++++++++++++
 2 files changed, 68 insertions(+), 1 deletion(-)
 create mode 100644 xFunc.Tests/ParserTests/TimeUnitTests.cs

diff --git a/xFunc.Maths/Parser.cs b/xFunc.Maths/Parser.cs
index 4bb1b4598..1837c3c94 100644
--- a/xFunc.Maths/Parser.cs
+++ b/xFunc.Maths/Parser.cs
@@ -727,7 +727,8 @@ private ImmutableArray<IExpression> ParseParameterList(ref TokenReader tokenRead
                    ParseAngleUnit(ref tokenReader) ??
                    ParsePowerUnit(ref tokenReader) ??
                    ParseMassUnit(ref tokenReader) ??
-                   ParseLengthUnit(ref tokenReader);
+                   ParseLengthUnit(ref tokenReader) ??
+                   ParseTimeUnit(ref tokenReader);
         if (unit is not null)
             return unit;
 
@@ -866,6 +867,32 @@ private ImmutableArray<IExpression> ParseParameterList(ref TokenReader tokenRead
             };
         });
 
+    private IExpression? ParseTimeUnit(ref TokenReader tokenReader)
+        => tokenReader.Scoped(this, static (Parser _, ref TokenReader reader) =>
+        {
+            var number = reader.GetCurrent(TokenKind.Number);
+            if (number.IsEmpty())
+                return null;
+
+            var id = reader.GetCurrent(Id);
+            if (id.IsEmpty())
+                return null;
+
+            return id.StringValue switch
+            {
+                "s" => TimeValue.Second(number.NumberValue).AsExpression(),
+                "ns" => TimeValue.Nanosecond(number.NumberValue).AsExpression(),
+                "μs" => TimeValue.Microsecond(number.NumberValue).AsExpression(),
+                "ms" => TimeValue.Millisecond(number.NumberValue).AsExpression(),
+                "min" => TimeValue.Minute(number.NumberValue).AsExpression(),
+                "h" => TimeValue.Hour(number.NumberValue).AsExpression(),
+                "day" => TimeValue.Day(number.NumberValue).AsExpression(),
+                "week" => TimeValue.Week(number.NumberValue).AsExpression(),
+                "year" => TimeValue.Year(number.NumberValue).AsExpression(),
+                _ => null,
+            };
+        });
+
     private IExpression? ParsePolarComplexNumber(ref TokenReader tokenReader)
         => tokenReader.Scoped(this, static (Parser _, ref TokenReader reader) =>
         {
diff --git a/xFunc.Tests/ParserTests/TimeUnitTests.cs b/xFunc.Tests/ParserTests/TimeUnitTests.cs
new file mode 100644
index 000000000..509408976
--- /dev/null
+++ b/xFunc.Tests/ParserTests/TimeUnitTests.cs
@@ -0,0 +1,40 @@
+namespace xFunc.Tests.ParserTests;
+
+public class TimeUnitTests : BaseParserTests
+{
+    [Fact]
+    public void ParseSecond()
+        => ParseTest("1 s", TimeValue.Second(1).AsExpression());
+
+    [Fact]
+    public void ParseNanosecond()
+        => ParseTest("1 ns", TimeValue.Nanosecond(1).AsExpression());
+
+    [Fact]
+    public void ParseMicrosecond()
+        => ParseTest("1 μs", TimeValue.Microsecond(1).AsExpression());
+
+    [Fact]
+    public void ParseMillisecond()
+        => ParseTest("1 ms", TimeValue.Millisecond(1).AsExpression());
+
+    [Fact]
+    public void ParseMinute()
+        => ParseTest("1 min", TimeValue.Minute(1).AsExpression());
+
+    [Fact]
+    public void ParseHour()
+        => ParseTest("1 h", TimeValue.Hour(1).AsExpression());
+
+    [Fact]
+    public void ParseDay()
+        => ParseTest("1 day", TimeValue.Day(1).AsExpression());
+
+    [Fact]
+    public void ParseWeek()
+        => ParseTest("1 week", TimeValue.Week(1).AsExpression());
+
+    [Fact]
+    public void ParseYear()
+        => ParseTest("1 year", TimeValue.Year(1).AsExpression());
+}
\ No newline at end of file