From 0002ed63eb8bd42d2106b71450eec2ee17f56e2e Mon Sep 17 00:00:00 2001
From: Helium314 <helium314@mailbox.org>
Date: Mon, 20 Nov 2023 01:11:06 +0100
Subject: [PATCH] enable validSpellingWordCache for spell checker

---
 .../latin/DictionaryFacilitatorImpl.java      | 25 ++++++++++---------
 .../latin/DictionaryFacilitatorProvider.java  |  7 +++++-
 2 files changed, 19 insertions(+), 13 deletions(-)

diff --git a/app/src/main/java/org/dslul/openboard/inputmethod/latin/DictionaryFacilitatorImpl.java b/app/src/main/java/org/dslul/openboard/inputmethod/latin/DictionaryFacilitatorImpl.java
index cd40c1d90..0538fff75 100644
--- a/app/src/main/java/org/dslul/openboard/inputmethod/latin/DictionaryFacilitatorImpl.java
+++ b/app/src/main/java/org/dslul/openboard/inputmethod/latin/DictionaryFacilitatorImpl.java
@@ -88,15 +88,8 @@ public class DictionaryFacilitatorImpl implements DictionaryFacilitator {
     private static final Class<?>[] DICT_FACTORY_METHOD_ARG_TYPES =
             new Class[] { Context.class, Locale.class, File.class, String.class, String.class };
 
-    // todo: these caches are never even set, as the corresponding functions are not called...
-    //  and even if they were set, one is only written, but never read, and the other one
-    //  is only read and thus empty and useless -> why?
-    //  anyway, we could just set the same cache using the set functions
-    //  but before doing this, check the potential performance gains
-    //   i.e. how long does a "isValidWord" check take -> on S4 mini 300 µs per dict if ok, but
-    //   sometimes it can also be a few ms
-    //   os if the spell checker is enabled, it's definitely reasonable to cache the results
-    //   but this needs to be done internally, as it should be by language
+    // todo: write cache never set, and never read (only written)
+    //  (initially was the same for the read cache, why?)
     private LruCache<String, Boolean> mValidSpellingWordReadCache;
     private LruCache<String, Boolean> mValidSpellingWordWriteCache;
 
@@ -461,6 +454,9 @@ public class DictionaryFacilitatorImpl implements DictionaryFacilitator {
         if (mValidSpellingWordWriteCache != null) {
             mValidSpellingWordWriteCache.evictAll();
         }
+        if (mValidSpellingWordReadCache != null) {
+            mValidSpellingWordReadCache.evictAll();
+        }
     }
 
     private void asyncReloadUninitializedMainDictionaries(final Context context,
@@ -912,11 +908,16 @@ public class DictionaryFacilitatorImpl implements DictionaryFacilitator {
                 return cachedValue;
             }
         }
+        boolean result = false;
         for (DictionaryGroup dictionaryGroup : mDictionaryGroups) {
-            if (isValidWord(word, ALL_DICTIONARY_TYPES, dictionaryGroup))
-                return true;
+            if (isValidWord(word, ALL_DICTIONARY_TYPES, dictionaryGroup)) {
+                result = true;
+                break;
+            }
         }
-        return false;
+        if (mValidSpellingWordReadCache != null)
+            mValidSpellingWordReadCache.put(word, result);
+        return result;
     }
 
     // this is unused, so leave it for now (redirecting to isValidWord seems to defeat the purpose...)
diff --git a/app/src/main/java/org/dslul/openboard/inputmethod/latin/DictionaryFacilitatorProvider.java b/app/src/main/java/org/dslul/openboard/inputmethod/latin/DictionaryFacilitatorProvider.java
index 718bacaee..a5086ddcb 100644
--- a/app/src/main/java/org/dslul/openboard/inputmethod/latin/DictionaryFacilitatorProvider.java
+++ b/app/src/main/java/org/dslul/openboard/inputmethod/latin/DictionaryFacilitatorProvider.java
@@ -6,11 +6,16 @@
 
 package org.dslul.openboard.inputmethod.latin;
 
+import android.util.LruCache;
+
 /**
  * Factory for instantiating DictionaryFacilitator objects.
  */
 public class DictionaryFacilitatorProvider {
     public static DictionaryFacilitator getDictionaryFacilitator(boolean isNeededForSpellChecking) {
-        return new DictionaryFacilitatorImpl();
+        final DictionaryFacilitator facilitator = new DictionaryFacilitatorImpl();
+        if (isNeededForSpellChecking)
+            facilitator.setValidSpellingWordReadCache(new LruCache<>(200));
+        return facilitator;
     }
 }