fix: use TimestampSerializer for timestamp data serialization

src/main/kotlin/com/ahdark/code/entities/github/webhook/Commit.kt

@@ -1,5 +1,6 @@
 package com.ahdark.code.entities.github.webhook
 
+import com.ahdark.code.serializer.TimestampSerializer
 import kotlinx.serialization.SerialName
 import kotlinx.serialization.Serializable
 
@@ -12,11 +13,14 @@ data class Commit(
 
     val distinct: Boolean,
     val message: String,
-    val timestamp: String,
+
+    @Serializable(with = TimestampSerializer::class)
+    val timestamp: Long,
+
     val url: String,
     val author: Author,
     val committer: Author,
     val added: List<String>,
     val removed: List<String>,
-    val modified: List<String>
+    val modified: List<String>,
 )

src/main/kotlin/com/ahdark/code/entities/github/webhook/Repository.kt

@@ -1,5 +1,6 @@
 package com.ahdark.code.entities.github.webhook
 
+import com.ahdark.code.serializer.TimestampSerializer
 import kotlinx.serialization.SerialName
 import kotlinx.serialization.Serializable
 
@@ -134,12 +135,15 @@ data class Repository(
     @SerialName("deployments_url")
     val deploymentsURL: String,
 
+    @Serializable(with = TimestampSerializer::class)
     @SerialName("created_at")
     val createdAt: Long,
 
+    @Serializable(with = TimestampSerializer::class)
     @SerialName("updated_at")
-    val updatedAt: String,
+    val updatedAt: Long,
 
+    @Serializable(with = TimestampSerializer::class)
     @SerialName("pushed_at")
     val pushedAt: Long,
 

src/main/kotlin/com/ahdark/code/serializer/TimestampSerializer.kt

@@ -0,0 +1,52 @@
+package com.ahdark.code.serializer
+
+import kotlinx.serialization.ExperimentalSerializationApi
+import kotlinx.serialization.KSerializer
+import kotlinx.serialization.SerializationException
+import kotlinx.serialization.Serializer
+import kotlinx.serialization.encoding.Decoder
+import kotlinx.serialization.encoding.Encoder
+import kotlinx.serialization.json.JsonDecoder
+import kotlinx.serialization.json.JsonPrimitive
+import kotlinx.serialization.json.long
+import kotlinx.serialization.json.longOrNull
+import java.text.SimpleDateFormat
+import java.util.*
+
+@OptIn(ExperimentalSerializationApi::class)
+@Serializer(forClass = Long::class)
+object TimestampSerializer : KSerializer<Long> {
+    private val dateFormat = SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss'Z'", Locale.US).apply {
+        timeZone = TimeZone.getTimeZone("UTC")
+    }
+
+    override fun serialize(encoder: Encoder, value: Long) {
+        encoder.encodeLong(value)
+    }
+
+    override fun deserialize(decoder: Decoder): Long {
+        if (decoder !is JsonDecoder) {
+            throw SerializationException("This serializer can only be used with JSON")
+        }
+
+        val element = decoder.decodeJsonElement()
+        return when {
+            element is JsonPrimitive && element.longOrNull != null -> element.long
+            element is JsonPrimitive -> parseDate(element.content)
+            else -> throw SerializationException("Invalid JSON element found for TimestampSerializer")
+        }
+    }
+
+    /**
+     * Parses a date string in the format "yyyy-MM-dd'T'HH:mm:ss'Z'".
+     *
+     * @throws SerializationException if the date string is not in the correct format.
+     */
+    private fun parseDate(dateString: String): Long {
+        return try {
+            dateFormat.parse(dateString)?.time ?: throw SerializationException("Invalid date format")
+        } catch (e: Exception) {
+            throw SerializationException("Error parsing date string: $dateString", e)
+        }
+    }
+}