improve error messages in notification

desktop/app/src/main/kotlin/com/abdownloadmanager/desktop/AppComponent.kt

@@ -34,6 +34,7 @@ import ir.amirab.downloader.utils.ExceptionUtils
 import ir.amirab.downloader.utils.OnDuplicateStrategy
 import com.abdownloadmanager.integration.Integration
 import com.abdownloadmanager.integration.IntegrationResult
+import ir.amirab.downloader.exception.TooManyErrorException
 import kotlinx.coroutines.flow.*
 import kotlinx.coroutines.launch
 import kotlinx.serialization.Serializable
@@ -274,43 +275,11 @@ class AppComponent(
             )
         )
     }
-
     init {
         downloadSystem
             .downloadEvents
             .onEach {
-                if (it.context[ResumedBy]?.by !is User){
-                    //only notify events that is started by user
-                    return@onEach
-                }
-//                or
-//                val qm = downloadSystem.queueManager
-//                val queueId = qm.findItemInQueue(it.downloadItem.id)
-//                if (queueId != null) {
-//                    return@onEach
-//                    // skip download events when download is triggered by queue
-////                    if (qm.getQueue(queue).isQueueActive){
-////                      return@onEach
-////                    }
-//                }
-                if (it is DownloadManagerEvents.OnJobCanceled) {
-                    if (!ExceptionUtils.isNormalCancellation(it.e)) {
-                        sendNotification(
-                            "downloadId=${it.downloadItem.id}",
-                            title = it.downloadItem.name,
-                            description = "Error" + it.e.localizedMessage?.let { " $it" }.orEmpty(),
-                            type = NotificationType.Error,
-                        )
-                    }
-                }
-                if (it is DownloadManagerEvents.OnJobCompleted) {
-                    sendNotification(
-                        tag = "downloadId=${it.downloadItem.id}",
-                        title = it.downloadItem.name,
-                        description = "Finished",
-                        type = NotificationType.Success,
-                    )
-                }
+                onNewDownloadEvent(it)
             }
             .launchIn(scope)
 //        IntegrationPortBroadcaster.cleanOnClose()
@@ -337,6 +306,57 @@ class AppComponent(
             }.launchIn(scope)
     }
 
+    private fun onNewDownloadEvent(it: DownloadManagerEvents) {
+        if (it.context[ResumedBy]?.by !is User){
+            //only notify events that is started by user
+            return
+        }
+//                or
+//                val qm = downloadSystem.queueManager
+//                val queueId = qm.findItemInQueue(it.downloadItem.id)
+//                if (queueId != null) {
+//                    return@onEach
+//                    // skip download events when download is triggered by queue
+////                    if (qm.getQueue(queue).isQueueActive){
+////                      return@onEach
+////                    }
+//                }
+        if (it is DownloadManagerEvents.OnJobCanceled) {
+            val exception = it.e
+            if (ExceptionUtils.isNormalCancellation(exception)) {
+                return
+            }
+            var isMaxTryReachedError = false
+            val actualCause = if (exception is TooManyErrorException){
+                isMaxTryReachedError=true
+                exception.findActualDownloadErrorCause()
+            }else exception
+            if (ExceptionUtils.isNormalCancellation(actualCause)) {
+                return
+            }
+            val prefix = if (isMaxTryReachedError) {
+                "Too Many Error: "
+            }else{
+                "Error: "
+            }
+            val reason = actualCause.message?:"Unknown"
+            sendNotification(
+                "downloadId=${it.downloadItem.id}",
+                title = it.downloadItem.name,
+                description = prefix + reason,
+                type = NotificationType.Error,
+            )
+        }
+        if (it is DownloadManagerEvents.OnJobCompleted) {
+            sendNotification(
+                tag = "downloadId=${it.downloadItem.id}",
+                title = it.downloadItem.name,
+                description = "Finished",
+                type = NotificationType.Success,
+            )
+        }
+    }
+
     override fun openAddDownloadDialog(
         links: List<DownloadCredentials>
     ) {

downloader/core/src/main/kotlin/ir/amirab/downloader/exception/PartTooManyErrorException.kt

@@ -3,5 +3,9 @@ package ir.amirab.downloader.exception
 import ir.amirab.downloader.part.Part
 
 class PartTooManyErrorException(
-    part: Part
-) : Exception("this part $part have too many exception")
+    part: Part,
+    override val cause: Throwable
+) : Exception(
+        "this part $part have too many errors",
+    cause,
+)

downloader/core/src/main/kotlin/ir/amirab/downloader/exception/TooManyErrorException.kt

@@ -1,8 +1,14 @@
 package ir.amirab.downloader.exception
 
 class TooManyErrorException(
-    lastException: Throwable,
+    override val cause: Throwable
 ) : Exception(
     "Download is stopped because all parts exceeds max retries",
-    lastException,
-)
+) {
+    fun findActualDownloadErrorCause(): Throwable {
+        return when (cause) {
+            is PartTooManyErrorException -> cause.cause
+            else -> cause
+        }
+    }
+}

downloader/core/src/main/kotlin/ir/amirab/downloader/part/PartDownloader.kt

@@ -83,6 +83,11 @@ class PartDownloader(
     @Volatile
     internal var tries = 0
 
+    // make sure to not lake resource in this exception
+    @Volatile
+    private var lastCriticalException: Throwable? = null
+
+    // make sure to not lake resource in this exception
     @Volatile
     private var lastException: Throwable? = null
 
@@ -100,6 +105,7 @@ class PartDownloader(
         }
         scope.launch {
             tries = 0
+            lastCriticalException = null
             lastException = null
             val result = kotlin.runCatching {
                 while (coroutineContext.isActive || !stop) {
@@ -110,7 +116,10 @@ class PartDownloader(
                     if (haveToManyErrors()) {
 //                        println("tell them we have error!")
                         iCantRetryAnymore(
-                            PartTooManyErrorException(part)
+                            PartTooManyErrorException(
+                                part,
+                                lastException?:Exception("BUG : if you see me please report it to the developer! when we encounter error so it have to be a least one last exception"),
+                            )
                         )
                     }
                     if (part.isCompleted) {
@@ -190,7 +199,7 @@ class PartDownloader(
 
     lateinit var onTooManyErrors: ((Throwable) -> Unit)
     private fun iCantRetryAnymore(throwable: Throwable) {
-        lastException = throwable
+        lastCriticalException = throwable
         GlobalScope.launch {
             onTooManyErrors(throwable)
         }
@@ -201,7 +210,7 @@ class PartDownloader(
     }
 
     private fun haveCriticalError(): Boolean {
-        return lastException != null
+        return lastCriticalException != null
     }
 
     internal fun injured(): Boolean {
@@ -333,6 +342,7 @@ class PartDownloader(
     }
 
     private fun onCanceled(e: Throwable) {
+        lastException = e
         val canceled = PartDownloadStatus.Canceled(e)
         onNewStatus(canceled)
         e.printStackIfNOtUsual()