Enhance time consistency between GitHub, Pingh server, and client

client/src/main/kotlin/io/spine/examples/pingh/client/TimestampExts.kt

@@ -30,7 +30,7 @@ import com.google.protobuf.Timestamp
 import com.google.protobuf.util.Timestamps
 import java.time.Duration
 import java.time.LocalDateTime
-import java.time.ZoneOffset
+import java.time.OffsetDateTime
 import java.time.format.DateTimeFormatter
 
 /**
@@ -64,15 +64,22 @@ internal fun Timestamp.add(duration: com.google.protobuf.Duration): Timestamp =
  * - If the difference is exactly one day, returns the string `"yesterday"`;
  * - In all other cases, returns the day and month.
  *
+ * Note that this timestamp must be in UTC. A default time zone offset
+ * is applied to the UTC time.
+ *
+ * @receiver The timestamp represents a time in the past in UTC.
  * @throws IllegalArgumentException if the `Timestamp` is not from the past.
  */
 public fun Timestamp.howMuchTimeHasPassed(): String {
-    val thisDatetime = LocalDateTime.ofEpochSecond(this.seconds, this.nanos, ZoneOffset.UTC)
+    val offset = OffsetDateTime.now().offset
+    val thisDatetime = LocalDateTime.ofEpochSecond(this.seconds, this.nanos, offset)
     val difference = Duration.between(
         thisDatetime,
-        LocalDateTime.now(ZoneOffset.UTC)
+        LocalDateTime.now(offset)
     )
-    require(difference > Duration.ZERO) { "" }
+    require(difference > Duration.ZERO) {
+        "This `Timestamp` must indicate a time in the past."
+    }
     return when {
         difference.toMinutes() < 1L -> "just now"
         difference.toMinutes() == 1L -> "a minute ago"

desktop/buildSrc/src/main/kotlin/io/spine/internal/dependency/Pingh.kt

@@ -28,6 +28,6 @@ package io.spine.internal.dependency
 
 // https://github.com/spine-examples/Pingh
 public object Pingh {
-    private const val version = "1.0.0-SNAPSHOT.5"
+    private const val version = "1.0.0-SNAPSHOT.6"
     public const val client: String = "io.spine.examples.pingh:client:$version"
 }

desktop/src/main/kotlin/io/spine/examples/pingh/desktop/TimestampExts.kt

@@ -28,7 +28,7 @@ package io.spine.examples.pingh.desktop
 
 import com.google.protobuf.Timestamp
 import java.time.LocalDateTime
-import java.time.ZoneOffset
+import java.time.OffsetDateTime
 import java.time.format.DateTimeFormatter
 
 /**
@@ -40,9 +40,14 @@ private val datetimeFormat = DateTimeFormatter.ofPattern("dd MMM HH:mm")
 /**
  * Converts `Timestamp` to the `dd MMM HH:mm` string.
  *
+ * Note that this timestamp must be in UTC. A default time zone offset
+ * is applied to the UTC time.
+ *
  * Examples:
  * - `10 May 14:37`
  * - `05 Sep 04:00`
+ *
+ * @receiver The timestamp in UTC.
  */
 internal fun Timestamp.toDatetime(): String =
     datetimeFormat.format(toLocalDateTime())
@@ -51,4 +56,4 @@ internal fun Timestamp.toDatetime(): String =
  * Converts this `Timestamp` to `LocalDateTime`.
  */
 private fun Timestamp.toLocalDateTime(): LocalDateTime =
-    LocalDateTime.ofEpochSecond(this.seconds, this.nanos, ZoneOffset.UTC)
+    LocalDateTime.ofEpochSecond(this.seconds, this.nanos, OffsetDateTime.now().offset)

version.gradle.kts

@@ -27,4 +27,4 @@
 /**
  * The version of the `Pingh` to publish.
  */
-val pinghVersion: String by extra("1.0.0-SNAPSHOT.5")
+val pinghVersion: String by extra("1.0.0-SNAPSHOT.6")