Ensure Filter DB modification never on main thread

app/src/main/java/com/hippo/ehviewer/client/EhFilter.kt

@@ -20,6 +20,9 @@ import arrow.core.memoize
 import com.hippo.ehviewer.EhDB
 import com.hippo.ehviewer.client.data.GalleryInfo
 import com.hippo.ehviewer.dao.Filter
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.launch
 
 private val regex = { p: Filter -> Regex(p.text) }.memoize()
 private inline fun List<Filter>.anyActive(predicate: (Filter) -> Boolean) = any { it.enable && predicate(it) }
@@ -31,10 +34,16 @@ object EhFilter {
     val tagNamespaceFilterList = mutableStateListOf<Filter>()
     val commenterFilterList = mutableStateListOf<Filter>()
     val commentFilterList = mutableStateListOf<Filter>()
-
-    fun Filter.remember() = EhDB.addFilter(this).also { if (it) memorizeFilter(this) }
-    fun Filter.trigger() = EhDB.triggerFilter(this)
-    fun Filter.forget() {
+    private val opScope = CoroutineScope(Dispatchers.IO.limitedParallelism(1))
+    private fun <R> Filter.launchOps(callback: ((R) -> Unit)? = null, ops: Filter.() -> R) = opScope.launch {
+        val r = ops()
+        callback?.invoke(r)
+    }
+    fun Filter.remember(callback: ((Boolean) -> Unit)? = null) = launchOps(callback) {
+        EhDB.addFilter(this).also { if (it) memorizeFilter(this) }
+    }
+    fun Filter.trigger(callback: ((Unit) -> Unit)? = null) = launchOps(callback) { EhDB.triggerFilter(this) }
+    fun Filter.forget() = launchOps {
         EhDB.deleteFilter(this)
         when (mode) {
             MODE_TITLE -> titleFilterList.remove(this)
@@ -43,7 +52,7 @@ object EhFilter {
             MODE_UPLOADER -> uploaderFilterList.remove(this)
             MODE_COMMENTER -> commenterFilterList.remove(this)
             MODE_COMMENT -> commentFilterList.remove(this)
-            else -> error("Unknown mode: " + mode)
+            else -> error("Unknown mode: $mode")
         }
     }
 

app/src/main/java/com/hippo/ehviewer/ui/settings/FilterScreen.kt

@@ -48,7 +48,6 @@ import com.hippo.ehviewer.databinding.DialogAddFilterBinding
 import com.hippo.ehviewer.ui.LocalNavController
 import com.hippo.ehviewer.ui.legacy.BaseDialogBuilder
 import kotlinx.coroutines.Dispatchers
-import kotlinx.coroutines.launch
 
 @Composable
 fun FilterScreen() {
@@ -83,14 +82,14 @@ fun FilterScreen() {
                 }
             }
             binding.textInputLayout.run {
-                if (!Filter(mArray.indexOf(text1), text!!).remember()) {
-                    error = context.getString(R.string.label_text_exist)
-                    return
-                } else {
-                    error = null
+                Filter(mArray.indexOf(text1), text!!).remember {
+                    if (it) {
+                        post { dialog.dismiss() }
+                    } else {
+                        post { error = context.getString(R.string.label_text_exist) }
+                    }
                 }
             }
-            dialog.dismiss()
         }
     }
 
@@ -139,17 +138,12 @@ fun FilterScreen() {
                         val filterCheckBoxRecomposeScope = currentRecomposeScope
                         Checkbox(
                             checked = filter.enable,
-                            onCheckedChange = {
-                                coroutineScope.launch {
-                                    filter.trigger()
-                                    filterCheckBoxRecomposeScope.invalidate()
-                                }
-                            },
+                            onCheckedChange = { filter.trigger { filterCheckBoxRecomposeScope.invalidate() } },
                         )
                         Text(text = filter.text)
                         Spacer(modifier = Modifier.weight(1F))
                         IconButton(
-                            onClick = { BaseDialogBuilder(context).setMessage(context.getString(R.string.delete_filter, filter.text)).setPositiveButton(R.string.delete) { _, which -> if (DialogInterface.BUTTON_POSITIVE == which) { coroutineScope.launch { filter.forget() } } }.setNegativeButton(android.R.string.cancel, null).show() },
+                            onClick = { BaseDialogBuilder(context).setMessage(context.getString(R.string.delete_filter, filter.text)).setPositiveButton(R.string.delete) { _, which -> if (DialogInterface.BUTTON_POSITIVE == which) { filter.forget() } }.setNegativeButton(android.R.string.cancel, null).show() },
                         ) {
                             Icon(imageVector = Icons.Default.Delete, contentDescription = null)
                         }