1 files changed, 44 insertions, 0 deletions
diff --git a/src/main/kotlin/util/TimeMark.kt b/src/main/kotlin/util/TimeMark.kt
new file mode 100644
index 0000000..1264212
--- /dev/null
+++ b/src/main/kotlin/util/TimeMark.kt
@@ -0,0 +1,44 @@
+
+
+package moe.nea.firmament.util
+
+import kotlin.time.Duration
+import kotlin.time.Duration.Companion.milliseconds
+
+class TimeMark private constructor(private val timeMark: Long) : Comparable<TimeMark> {
+    fun passedTime() = if (timeMark == 0L) Duration.INFINITE else (System.currentTimeMillis() - timeMark).milliseconds
+
+    operator fun minus(other: TimeMark): Duration {
+        if (other.timeMark == timeMark)
+            return 0.milliseconds
+        if (other.timeMark == 0L)
+            return Duration.INFINITE
+        if (timeMark == 0L)
+            return -Duration.INFINITE
+        return (timeMark - other.timeMark).milliseconds
+    }
+
+    companion object {
+        fun now() = TimeMark(System.currentTimeMillis())
+        fun farPast() = TimeMark(0L)
+        fun ago(timeDelta: Duration): TimeMark {
+            if (timeDelta.isFinite()) {
+                return TimeMark(System.currentTimeMillis() - timeDelta.inWholeMilliseconds)
+            }
+            require(timeDelta.isPositive())
+            return farPast()
+        }
+    }
+
+    override fun hashCode(): Int {
+        return timeMark.hashCode()
+    }
+
+    override fun equals(other: Any?): Boolean {
+        return other is TimeMark && other.timeMark == timeMark
+    }
+
+    override fun compareTo(other: TimeMark): Int {
+        return this.timeMark.compareTo(other.timeMark)
+    }
+}