add MediaFileActualityChecker

cache/content/common/src/commonMain/kotlin/dev/inmo/tgbotapi/libraries/cache/media/common/DefaultMessageContentCache.kt

@@ -1,6 +1,7 @@
 package dev.inmo.tgbotapi.libraries.cache.media.common
 
 import dev.inmo.tgbotapi.bot.TelegramBot
+import dev.inmo.tgbotapi.requests.DeleteMessage
 import dev.inmo.tgbotapi.requests.DownloadFileStream
 import dev.inmo.tgbotapi.requests.abstracts.MultipartFile
 import dev.inmo.tgbotapi.requests.get.GetFile
@@ -16,6 +17,9 @@ class DefaultMessageContentCache<K>(
     private val bot: TelegramBot,
     private val filesRefreshingChatId: ChatId,
     private val simpleMessageContentCache: MessagesSimpleCache<K>,
+    private val mediaFileActualityChecker: MediaFileActualityChecker = MediaFileActualityChecker.WithDelay(
+        MediaFileActualityChecker.Default(filesRefreshingChatId)
+    ),
     private val messagesFilesCache: MessagesFilesCache<K> = InMemoryMessagesFilesCache()
 ) : MessageContentCache<K> {
     override suspend fun save(content: MessageContent): K {
@@ -48,6 +52,10 @@ class DefaultMessageContentCache<K>(
             messagesFilesCache.set(key, filename, inputAllocator)
         }.onFailure {
             simpleMessageContentCache.remove(key)
+        }.onSuccess {
+            with(mediaFileActualityChecker) {
+                bot.saved(content)
+            }
         }
 
         return key
@@ -56,10 +64,7 @@ class DefaultMessageContentCache<K>(
     override suspend fun get(k: K): MessageContent? {
         val savedSimpleContent = simpleMessageContentCache.get(k) ?: return null
 
-        if (savedSimpleContent is MediaContent) {
-            runCatching {
-                bot.execute(GetFile(savedSimpleContent.media.fileId))
-            }.onFailure {
+        if (savedSimpleContent is MediaContent && !with(mediaFileActualityChecker) { bot.isActual(savedSimpleContent) }) {
             val savedFileContentAllocator = messagesFilesCache.get(k) ?: error("Unexpected absence of $k file for content ($simpleMessageContentCache)")
             val newContent = bot.execute(
                 when (savedSimpleContent.asInputMedia()) {
@@ -104,7 +109,6 @@ class DefaultMessageContentCache<K>(
             simpleMessageContentCache.update(k, newContent.content)
             return newContent.content
         }
-        }
         return savedSimpleContent
     }
 
@@ -122,7 +126,10 @@ class DefaultMessageContentCache<K>(
             bot: TelegramBot,
             filesRefreshingChatId: ChatId,
             simpleMessageContentCache: MessagesSimpleCache<String> = InMemoryMessagesSimpleCache(),
+            mediaFileActualityChecker: MediaFileActualityChecker = MediaFileActualityChecker.WithDelay(
+                MediaFileActualityChecker.Default(filesRefreshingChatId)
+            ),
             messagesFilesCache: MessagesFilesCache<String> = InMemoryMessagesFilesCache()
-        ) = DefaultMessageContentCache(bot, filesRefreshingChatId, simpleMessageContentCache, messagesFilesCache)
+        ) = DefaultMessageContentCache(bot, filesRefreshingChatId, simpleMessageContentCache, mediaFileActualityChecker, messagesFilesCache)
     }
 }

cache/content/common/src/commonMain/kotlin/dev/inmo/tgbotapi/libraries/cache/media/common/MediaFileActualityChecker.kt

@@ -0,0 +1,55 @@
+package dev.inmo.tgbotapi.libraries.cache.media.common
+
+import com.soywiz.klock.DateTime
+import com.soywiz.klock.milliseconds
+import dev.inmo.tgbotapi.bot.TelegramBot
+import dev.inmo.tgbotapi.requests.DeleteMessage
+import dev.inmo.tgbotapi.requests.abstracts.FileId
+import dev.inmo.tgbotapi.types.ChatId
+import dev.inmo.tgbotapi.types.MilliSeconds
+import dev.inmo.tgbotapi.types.message.content.abstracts.MediaContent
+
+fun interface MediaFileActualityChecker {
+    suspend fun TelegramBot.isActual(mediaContent: MediaContent): Boolean
+    suspend fun TelegramBot.saved(mediaContent: MediaContent) {}
+
+    class Default(
+        private val checkingChatId: ChatId
+    ) : MediaFileActualityChecker {
+        override suspend fun TelegramBot.isActual(mediaContent: MediaContent): Boolean {
+            return runCatching {
+                execute(mediaContent.createResend(checkingChatId)).also { sentMessage ->
+                    execute(DeleteMessage(sentMessage.chat.id, sentMessage.messageId))
+                }
+            }.isSuccess
+        }
+    }
+
+    class WithDelay(
+        private val underhoodChecker: MediaFileActualityChecker,
+        private val checkingDelay: MilliSeconds = 24 * 60 * 60 * 1000L // one day
+    ) : MediaFileActualityChecker {
+        private val fileIdChecksMap = mutableMapOf<FileId, DateTime>()
+        private val checkingDelayTimeSpan = checkingDelay.milliseconds
+
+        override suspend fun TelegramBot.isActual(mediaContent: MediaContent): Boolean {
+            val now = DateTime.now()
+            val lastCheck = fileIdChecksMap[mediaContent.media.fileId]
+            return if (lastCheck == null || now - lastCheck > checkingDelayTimeSpan) {
+                with(underhoodChecker) {
+                    isActual(mediaContent)
+                }.also {
+                    if (it) {
+                        fileIdChecksMap[mediaContent.media.fileId] = now
+                    }
+                }
+            } else {
+                true
+            }
+        }
+
+        override suspend fun TelegramBot.saved(mediaContent: MediaContent) {
+            fileIdChecksMap[mediaContent.media.fileId] = DateTime.now()
+        }
+    }
+}