Simply delete all rules when no sources are given

app/src/main/java/com/frostnerd/smokescreen/database/dao/DnsRuleDao.kt

@@ -48,8 +48,8 @@ interface DnsRuleDao {
     @Query("DELETE FROM DnsRule WHERE importedFrom IS NOT NULL")
     fun deleteAllNonUserRules()
 
-    @Query("UPDATE DnsRule SET stagingType=1 WHERE importedFrom IS NOT NULL AND stagingType=0")
-    fun markNonUserRulesForDeletion()
+    @Query("UPDATE DnsRule SET stagingType=1 WHERE importedFrom IS NOT NULL AND stagingType=0 AND importedFrom IN(:sources)")
+    fun markNonUserRulesForDeletion(sources:List<Long>)
 
     @Query("UPDATE DnsRule SET stagingType=0 WHERE importedFrom=:hostSourceId AND stagingType=1")
     fun unstageRulesOfSource(hostSourceId:Long)

app/src/main/java/com/frostnerd/smokescreen/service/RuleImportService.kt

@@ -174,8 +174,12 @@ class RuleImportService : IntentService("RuleImportService") {
 
     private fun startWork() {
         val dnsRuleDao = getDatabase().dnsRuleDao()
-        dnsRuleDao.markNonUserRulesForDeletion() // Stage all, ignoring if the source is actually processed in this run
-        dnsRuleDao.deleteStagedRules()
+        if(sourcesIds.isEmpty()) {
+            dnsRuleDao.deleteAllNonUserRules()
+        } else {
+            dnsRuleDao.markNonUserRulesForDeletion(sourcesIds) // Stage all, ignoring if the source is actually processed in this run
+            dnsRuleDao.deleteStagedRules()
+        }
         var count = 0
         val newChecksums = mutableMapOf<HostSource, String>()
         sources.forEach {
@@ -242,11 +246,13 @@ class RuleImportService : IntentService("RuleImportService") {
         }
         if (!isAborted) {
             updateNotificationFinishing()
-            log("Delete rules staged for deletion")
-            dnsRuleDao.deleteMarkedRules()
-            log("Committing staging")
-            dnsRuleDao.commitStaging()
-            dnsRuleDao.deleteStagedRules()
+            if(sourcesIds.isNotEmpty()) {
+                log("Delete rules staged for deletion")
+                dnsRuleDao.deleteMarkedRules()
+                log("Committing staging")
+                dnsRuleDao.commitStaging()
+                dnsRuleDao.deleteStagedRules()
+            }
             log("Recreating database indices")
             getDatabase().recreateDnsRuleIndizes()
             log("Updating Etag values for sources")