Improve Autosuggestions

app/src/keyboards/java/be/scri/helpers/AutocompletionHandler.kt

@@ -46,7 +46,8 @@ class AutocompletionHandler(
                     return@Runnable
                 }
 
-                val completions = ime.getAutocompletions(currentWord, limit = 5)
+                val previousWord = ime.getPreviousWordBeforeCursor()
+                val completions = ime.getAutocompletions(currentWord, previousWord, limit = 5)
 
                 if (completions.isNotEmpty()) {
                     ime.updateAutocompleteSuggestions(completions)

app/src/keyboards/java/be/scri/services/GeneralKeyboardIME.kt

@@ -1112,10 +1112,11 @@ abstract class GeneralKeyboardIME(
      */
     fun getAutocompletions(
         prefix: String,
+        previousWord: String? = null,
         limit: Int = 3,
     ): List<String> {
         if (this::nativeSuggestionEngine.isInitialized) {
-            val nativeCompletions = nativeSuggestionEngine.getAutocompletions(language, prefix, limit)
+            val nativeCompletions = nativeSuggestionEngine.getAutocompletions(language, prefix, previousWord, limit)
             if (nativeCompletions.isNotEmpty()) {
                 return nativeCompletions
             }
@@ -1156,6 +1157,18 @@ abstract class GeneralKeyboardIME(
      */
     fun getLastWordBeforeCursor(): String? = getText()?.trim()?.split("\\s+".toRegex())?.lastOrNull()
 
+    /**
+     * Extracts the word immediately before the one currently being composed, i.e. the last
+     * completed word preceding the in-progress word at the cursor. Used to give the autocomplete
+     * engine sentence context so it can bias completions instead of scoring the prefix in isolation.
+     *
+     * @return The previous completed word as a [String], or null if there isn't one.
+     */
+    fun getPreviousWordBeforeCursor(): String? {
+        val words = getText()?.trim()?.split("\\s+".toRegex()) ?: return null
+        return words.getOrNull(words.size - 2)
+    }
+
     /**
      * Retrieves the text immediately preceding the cursor.
      *

app/src/main/java/be/scri/helpers/NativeSuggestionEngine.kt

@@ -116,25 +116,38 @@ class NativeSuggestionEngine(private val context: Context) {
     fun getAutocompletions(
         language: String,
         prefix: String,
+        previousWord: String? = null,
         limit: Int = 3
     ): List<String> {
         val dict = getDictionary(language) ?: return emptyList()
         if (prefix.isBlank()) return emptyList()
 
         return try {
             val composedData = ComposedData.createForWord(prefix)
+            val ngramContext =
+                if (previousWord.isNullOrBlank()) {
+                    NgramContext.EMPTY_PREV_WORDS_INFO
+                } else {
+                    NgramContext(NgramContext.WordInfo(previousWord))
+                }
             val suggestions = dict.getSuggestions(
                 composedData,
-                NgramContext.EMPTY_PREV_WORDS_INFO,
+                ngramContext,
                 dummyProximityInfo.nativeProximityInfo, // proximityInfoHandle
-                SettingsValuesForSuggestion(false, false),
+                SettingsValuesForSuggestion(true, false), // blockPotentiallyOffensive, spaceAwareGesture
                 1, // sessionId
                 1.0f, // weightForLocale
                 null // inOutWeightOfLangModelVsSpatialModel
             )
 
+            val isCapitalized = StringUtils.isWordCapitalized(prefix)
             suggestions?.map { it.mWord }
-                ?.filter { it.isNotBlank() && it.lowercase(Locale.ROOT) != prefix.lowercase(Locale.ROOT) }
+                ?.filter {
+                    it.isNotBlank() &&
+                        it.startsWith(prefix, ignoreCase = true) &&
+                        it.lowercase(Locale.ROOT) != prefix.lowercase(Locale.ROOT)
+                }
+                ?.map { if (isCapitalized) it.replaceFirstChar { c -> c.uppercaseChar() } else it }
                 ?.take(limit)
                 ?: emptyList()
         } catch (e: Exception) {
@@ -162,14 +175,14 @@ class NativeSuggestionEngine(private val context: Context) {
                 composedData,
                 ngramContext,
                 dummyProximityInfo.nativeProximityInfo, // proximityInfoHandle
-                SettingsValuesForSuggestion(false, false),
+                SettingsValuesForSuggestion(true, false), // blockPotentiallyOffensive, spaceAwareGesture
                 1, // sessionId
                 1.0f, // weightForLocale
                 null // inOutWeightOfLangModelVsSpatialModel
             )
 
             suggestions?.map { it.mWord }
-                ?.filter { it.isNotBlank() }
+                ?.filter { it.isNotBlank() && it.lowercase(Locale.ROOT) != lastWord.lowercase(Locale.ROOT) }
                 ?.take(limit)
                 ?: emptyList()
         } catch (e: Exception) {

app/src/main/java/be/scri/latin/common/ComposedData.kt

@@ -8,8 +8,6 @@
  */
 package be.scri.latin.common
 
-import kotlin.random.Random
-
 /** An immutable class that encapsulates a snapshot of word composition data. */
 class ComposedData(
     @JvmField val mInputPointers: InputPointers,
@@ -48,10 +46,12 @@ class ComposedData(
     companion object {
         fun createForWord(word: String): ComposedData {
             val codePoints = StringUtils.toCodePointArray(word)
-            val coordinates = CoordinateUtils.newCoordinateArray(codePoints.size)
-            for (i in codePoints.indices) {
-                CoordinateUtils.setXYInArray(coordinates, i, Random.nextBits(2), Random.nextBits(2))
-            }
+            val coordinates =
+                CoordinateUtils.newCoordinateArray(
+                    codePoints.size,
+                    Constants.NOT_A_COORDINATE,
+                    Constants.NOT_A_COORDINATE,
+                )
             val pointers = InputPointers(codePoints.size).apply {
                 for (i in codePoints.indices) {
                     addPointer(CoordinateUtils.xFromArray(coordinates, i), CoordinateUtils.yFromArray(coordinates, i), 0, 0)