feat: added initial implementation of RobotKeyboard

Author: AlmasB

fxgl/src/main/kotlin/com/almasb/fxgl/app/services/OSService.kt

@@ -13,6 +13,7 @@ import com.almasb.fxgl.logging.Logger
 import javafx.geometry.Point2D
 import javafx.geometry.Rectangle2D
 import javafx.scene.image.Image
+import javafx.scene.input.KeyCode
 import javafx.scene.input.MouseButton
 import javafx.scene.robot.Robot
 import java.util.Optional
@@ -31,6 +32,8 @@ class OSService : EngineService() {
 
     val mouse: RobotMouse by lazy { RobotMouse(robot) }
 
+    val keyboard: RobotKeyboard by lazy { RobotKeyboard(robot) }
+
     /**
      * @return a screenshot of the [region] in OS screen space, or an empty [Optional] if fails.
      */
@@ -142,4 +145,104 @@ internal constructor(private val robot: Robot) {
             log.warning("Failed to move mouse", e)
         }
     }
+}
+
+/**
+ * An abstraction over an OS-level keyboard allowing to perform
+ * actions outside the game window.
+ */
+class RobotKeyboard
+internal constructor(private val robot: Robot) {
+
+    /**
+     * Types given [text] using OS keyboard.
+     */
+    fun type(text: String) {
+        text.forEach { type(it) }
+    }
+
+    private fun type(ch: Char) {
+        val key: KeyCode
+
+        var isShift = false
+
+        if (Character.isLetter(ch)) {
+            key = KeyCode.valueOf(ch.uppercase())
+            isShift = ch.isUpperCase()
+        } else {
+            key = when(ch) {
+                ' ' -> KeyCode.SPACE
+                '?' -> {
+                    isShift = true
+                    KeyCode.SLASH
+                }
+                '!' -> {
+                    isShift = true
+                    KeyCode.DIGIT1
+                }
+                ',' -> KeyCode.COMMA
+                '.' -> KeyCode.PERIOD
+                '_' -> {
+                    isShift = true
+                    KeyCode.MINUS
+                }
+                '-' -> KeyCode.MINUS
+                '+' -> {
+                    isShift = true
+                    KeyCode.EQUALS
+                }
+                '*' -> {
+                    isShift = true
+                    KeyCode.DIGIT8
+                }
+                '/' -> KeyCode.SLASH
+                '£' -> {
+                    isShift = true
+                    KeyCode.DIGIT3
+                }
+                '$' -> {
+                    isShift = true
+                    KeyCode.DIGIT4
+                }
+                '@' -> {
+                    isShift = true
+                    KeyCode.QUOTE
+                }
+                '%' -> {
+                    isShift = true
+                    KeyCode.DIGIT5
+                }
+
+                else -> {
+                    log.warning("Cannot convert char to key: $ch")
+                    KeyCode.CONTROL
+                }
+            }
+        }
+
+        if (isShift) {
+            press(KeyCode.SHIFT)
+        }
+
+        type(key)
+
+        if (isShift) {
+            release(KeyCode.SHIFT)
+        }
+    }
+
+    /**
+     * Types (presses, then releases) given [key] using OS keyboard.
+     */
+    fun type(key: KeyCode) {
+        robot.keyType(key)
+    }
+
+    fun press(key: KeyCode) {
+        robot.keyPress(key)
+    }
+
+    fun release(key: KeyCode) {
+        robot.keyRelease(key)
+    }
 }