refactor: extract KeyboardStateManager from GeneralKeyboardIME (#426)

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

@@ -0,0 +1,80 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+package be.scri.helpers
+
+import be.scri.models.ScribeState
+
+/**
+ * Manages the current state transitions and state flags for the Scribe keyboard command system.
+ */
+class KeyboardStateManager {
+    /**
+     * The active state of the keyboard command system.
+     */
+    var currentState: ScribeState = ScribeState.IDLE
+
+    /**
+     * Records the previous command source when an invalid state occurs.
+     */
+    var invalidCommandSource: ScribeState = ScribeState.IDLE
+
+    /**
+     * Checks if the keyboard is currently in the `IDLE` state.
+     */
+    val isIdle: Boolean
+        get() = currentState == ScribeState.IDLE
+
+    /**
+     * Checks if the keyboard is currently in the `SELECT_COMMAND` state.
+     */
+    val isSelectCommand: Boolean
+        get() = currentState == ScribeState.SELECT_COMMAND
+
+    /**
+     * Checks if a command bar mode (translate, conjugate, plural, etc.) is active.
+     */
+    val isCommandBarActive: Boolean
+        get() = currentState != ScribeState.IDLE && currentState != ScribeState.SELECT_COMMAND
+
+    /**
+     * Checks if the keyboard is currently in the `INVALID` state.
+     */
+    val isInvalid: Boolean
+        get() = currentState == ScribeState.INVALID
+
+    /**
+     * Checks if the keyboard is currently in the `ALREADY_PLURAL` state.
+     */
+    val isAlreadyPlural: Boolean
+        get() = currentState == ScribeState.ALREADY_PLURAL
+
+    /**
+     * Transitions the keyboard state to [newState].
+     */
+    fun moveToState(newState: ScribeState) {
+        currentState = newState
+    }
+
+    /**
+     * Resets the keyboard state to `IDLE`.
+     */
+    fun moveToIdle() {
+        currentState = ScribeState.IDLE
+    }
+
+    /**
+     * Transitions the keyboard to the `INVALID` state and records the [source] state.
+     */
+    fun setInvalidState(source: ScribeState) {
+        invalidCommandSource = source
+        currentState = ScribeState.INVALID
+    }
+
+    /**
+     * Resets both [currentState] and [invalidCommandSource] to `IDLE`.
+     */
+    fun reset() {
+        currentState = ScribeState.IDLE
+        invalidCommandSource = ScribeState.IDLE
+    }
+}

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

@@ -51,6 +51,7 @@ import be.scri.helpers.EmojiUtils.insertEmoji
 import be.scri.helpers.FloatingKeyboardHandler
 import be.scri.helpers.KeyboardBase
 import be.scri.helpers.KeyboardLanguageMappingConstants
+import be.scri.helpers.KeyboardStateManager
 import be.scri.helpers.LanguageMappingConstants.getLanguageAlias
 import be.scri.helpers.NativeSuggestionEngine
 import be.scri.helpers.PreferencesHelper
@@ -187,8 +188,19 @@ abstract class GeneralKeyboardIME(
     private var currentEnterKeyType: Int? = null
     private var isNumericKeyboardActive: Boolean = false
 
-    internal var currentState: ScribeState = ScribeState.IDLE
-    internal var invalidCommandSource: ScribeState = ScribeState.IDLE
+    internal val stateManager = KeyboardStateManager()
+
+    internal var currentState: ScribeState
+        get() = stateManager.currentState
+        set(value) {
+            stateManager.currentState = value
+        }
+
+    internal var invalidCommandSource: ScribeState
+        get() = stateManager.invalidCommandSource
+        set(value) {
+            stateManager.invalidCommandSource = value
+        }
 
     // Properties used by BackspaceHandler, delegated to UI Manager.
     internal var currentCommandBarHint: String
@@ -793,7 +805,7 @@ abstract class GeneralKeyboardIME(
      */
     internal fun moveToIdleState() {
         clearSuggestionData()
-        currentState = ScribeState.IDLE
+        stateManager.moveToIdle()
         saveConjugateModeType("none")
         currentVerbForConjugation = null
         selectedConjugationSubCategory = null
@@ -813,9 +825,9 @@ abstract class GeneralKeyboardIME(
     // MARK: KeyboardUIListener
 
     override fun onScribeKeyOptionsClicked() {
-        if (currentState == ScribeState.IDLE) {
+        if (stateManager.isIdle) {
             clearSuggestionData()
-            currentState = ScribeState.SELECT_COMMAND
+            stateManager.moveToState(ScribeState.SELECT_COMMAND)
             saveConjugateModeType("none")
             currentVerbForConjugation = null
         } else {
@@ -829,20 +841,20 @@ abstract class GeneralKeyboardIME(
     }
 
     override fun onTranslateClicked() {
-        currentState = ScribeState.TRANSLATE
+        stateManager.moveToState(ScribeState.TRANSLATE)
         saveConjugateModeType("none")
         refreshUI()
     }
 
     override fun onConjugateClicked() {
-        if (currentState != ScribeState.SELECT_VERB_CONJUNCTION) {
-            currentState = ScribeState.CONJUGATE
+        if (stateManager.currentState != ScribeState.SELECT_VERB_CONJUNCTION) {
+            stateManager.moveToState(ScribeState.CONJUGATE)
         }
         refreshUI()
     }
 
     override fun onPluralClicked() {
-        currentState = ScribeState.PLURAL
+        stateManager.moveToState(ScribeState.PLURAL)
         saveConjugateModeType("none")
         if (isPluralCapitalized) keyboard?.mShiftState = SHIFT_ON_ONE_CHAR
         refreshUI()
@@ -992,8 +1004,7 @@ abstract class GeneralKeyboardIME(
             }
 
         if (commandModeOutput.isEmpty()) {
-            invalidCommandSource = currentState
-            currentState = ScribeState.INVALID
+            stateManager.setInvalidState(currentState)
             refreshUI()
         } else {
             applyCommandOutput(commandModeOutput, inputConnection)
@@ -1027,14 +1038,12 @@ abstract class GeneralKeyboardIME(
 
         conjugateLabels = dbManagers.conjugateDataManager.extractConjugateHeadings(dataContract, searchInput)
 
-        currentState =
-            if (conjugateOutput == null) {
-                invalidCommandSource = ScribeState.CONJUGATE
-                ScribeState.INVALID
-            } else {
-                saveConjugateModeType(language)
-                ScribeState.SELECT_VERB_CONJUNCTION
-            }
+        if (conjugateOutput == null) {
+            stateManager.setInvalidState(ScribeState.CONJUGATE)
+        } else {
+            saveConjugateModeType(language)
+            stateManager.moveToState(ScribeState.SELECT_VERB_CONJUNCTION)
+        }
         refreshUI()
     }
 

app/src/testKeyboards/kotlin/be/scri/helpers/KeyboardStateManagerTest.kt

@@ -0,0 +1,77 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+package be.scri.helpers
+
+import be.scri.models.ScribeState
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertFalse
+import org.junit.Assert.assertTrue
+import org.junit.Before
+import org.junit.Test
+
+class KeyboardStateManagerTest {
+    private lateinit var stateManager: KeyboardStateManager
+
+    @Before
+    fun setUp() {
+        stateManager = KeyboardStateManager()
+    }
+
+    @Test
+    fun initialState_isIdle() {
+        assertEquals(ScribeState.IDLE, stateManager.currentState)
+        assertEquals(ScribeState.IDLE, stateManager.invalidCommandSource)
+        assertTrue(stateManager.isIdle)
+        assertFalse(stateManager.isSelectCommand)
+        assertFalse(stateManager.isCommandBarActive)
+        assertFalse(stateManager.isInvalid)
+        assertFalse(stateManager.isAlreadyPlural)
+    }
+
+    @Test
+    fun moveToState_updatesCurrentState() {
+        stateManager.moveToState(ScribeState.TRANSLATE)
+        assertEquals(ScribeState.TRANSLATE, stateManager.currentState)
+        assertFalse(stateManager.isIdle)
+        assertTrue(stateManager.isCommandBarActive)
+
+        stateManager.moveToState(ScribeState.SELECT_COMMAND)
+        assertEquals(ScribeState.SELECT_COMMAND, stateManager.currentState)
+        assertTrue(stateManager.isSelectCommand)
+        assertFalse(stateManager.isCommandBarActive)
+    }
+
+    @Test
+    fun moveToIdle_resetsToIdle() {
+        stateManager.moveToState(ScribeState.CONJUGATE)
+        stateManager.moveToIdle()
+        assertEquals(ScribeState.IDLE, stateManager.currentState)
+        assertTrue(stateManager.isIdle)
+    }
+
+    @Test
+    fun setInvalidState_setsInvalidStateAndRecordsSource() {
+        stateManager.moveToState(ScribeState.PLURAL)
+        stateManager.setInvalidState(ScribeState.PLURAL)
+
+        assertEquals(ScribeState.INVALID, stateManager.currentState)
+        assertEquals(ScribeState.PLURAL, stateManager.invalidCommandSource)
+        assertTrue(stateManager.isInvalid)
+    }
+
+    @Test
+    fun isAlreadyPlural_returnsTrueWhenStateIsAlreadyPlural() {
+        stateManager.moveToState(ScribeState.ALREADY_PLURAL)
+        assertTrue(stateManager.isAlreadyPlural)
+    }
+
+    @Test
+    fun reset_resetsStateAndInvalidSourceToIdle() {
+        stateManager.setInvalidState(ScribeState.TRANSLATE)
+        stateManager.reset()
+
+        assertEquals(ScribeState.IDLE, stateManager.currentState)
+        assertEquals(ScribeState.IDLE, stateManager.invalidCommandSource)
+        assertTrue(stateManager.isIdle)
+    }
+}