Solutions zip: use real file/submission timestamps instead of epoch (fixes bogus years)

web/src/main/kotlin/ru/ysu/lms/web/admin/AdminSupport.kt

@@ -23,6 +23,7 @@ import java.io.ByteArrayInputStream
 import java.io.ByteArrayOutputStream
 import java.net.URLEncoder
 import java.nio.charset.StandardCharsets
+import java.time.Instant
 import java.util.zip.ZipEntry
 import java.util.zip.ZipInputStream
 import java.util.zip.ZipOutputStream
@@ -164,14 +165,14 @@ abstract class AdminSupport(
     ): ByteArray {
         val out = ByteArrayOutputStream()
         ZipOutputStream(out).use { zos ->
-            zos.putNextEntry(ZipEntry("ОПИСАНИЕ.txt").apply { time = 0 })
+            zos.putNextEntry(ZipEntry("ОПИСАНИЕ.txt"))
             zos.write("Архив сдач группы $groupName (последние попытки)\n".toByteArray(Charsets.UTF_8))
             zos.closeEntry()
             for (lab in labs) {
                 for (sub in api.labSubmissions(token, lab.id)) {
                     val student = studentById[sub.studentId] ?: continue
                     val bytes = api.downloadSubmissionAsAdmin(token, sub.id).bytes
-                    appendSubmissionArchive(zos, lab, student, bytes)
+                    appendSubmissionArchive(zos, lab, student, bytes, sub.createdAt)
                 }
             }
         }
@@ -183,13 +184,21 @@ abstract class AdminSupport(
         lab: LabSummaryDto,
         student: StudentRowDto,
         submissionZip: ByteArray,
+        submissionCreatedAt: String? = null,
     ) {
+        val fallbackMillis =
+            submissionCreatedAt
+                ?.let { runCatching { Instant.parse(it).toEpochMilli() }.getOrNull() }
+                ?: System.currentTimeMillis()
         ZipInputStream(ByteArrayInputStream(submissionZip)).use { zin ->
             var entry = zin.nextEntry
             while (entry != null) {
                 if (!entry.isDirectory) {
                     val safeName = student.fullName.replace(Regex("[\\\\/:*?\"<>|]"), "_")
-                    zos.putNextEntry(ZipEntry("ЛР${lab.number}/${student.studentNo}_$safeName/${entry.name}").apply { time = 0 })
+                    val entryMillis = entry.time.takeIf { it > 0 } ?: fallbackMillis
+                    zos.putNextEntry(
+                        ZipEntry("ЛР${lab.number}/${student.studentNo}_$safeName/${entry.name}").apply { time = entryMillis },
+                    )
                     zin.copyTo(zos)
                     zos.closeEntry()
                 }