Complete secure log viewing and retention

app/src/main/java/se/ajpanton/notificationlog/capture/NotificationCaptureService.kt

@@ -91,10 +91,17 @@ class NotificationCaptureService : NotificationListenerService() {
         writeExecutor.execute {
             try {
                 if (retainImage) {
-                    imageStore.save(entry.imageId!!, snapshot.imageBytes!!)
+                    try {
+                        imageStore.save(entry.imageId!!, snapshot.imageBytes!!)
+                    } catch (error: Exception) {
+                        Log.w(TAG, "Could not retain notification image; keeping the text event", error)
+                        logStore.append(entry.copy(imageId = null))
+                        return@execute
+                    }
                 }
                 logStore.append(entry)
             } catch (error: Exception) {
+                entry.imageId?.let(imageStore::delete)
                 Log.e(TAG, "Could not persist notification log entry", error)
             }
         }
@@ -107,7 +114,10 @@ class NotificationCaptureService : NotificationListenerService() {
         val image = snapshot.hasImage && NotificationRuleEvaluator.allows(
             ruleStore.ruleFor(LoggingType.IMAGE_CONTENT), snapshot.packageName,
         )
-        return listOfNotNull(text, if (image) "[image]" else null).joinToString(" — ").ifEmpty { null }
+        return listOfNotNull(text, if (image) "[image]" else null)
+            .joinToString(" — ")
+            .take(MAX_CONTENT_CHARACTERS)
+            .ifEmpty { null }
     }
 
     private fun appName(packageName: String): String = try {
@@ -147,5 +157,6 @@ class NotificationCaptureService : NotificationListenerService() {
 
     private companion object {
         const val TAG = "NotificationCapture"
+        const val MAX_CONTENT_CHARACTERS = 16_000
     }
 }