Add playback controls

app/src/main/java/com/github/damontecres/dolphin/Extensions.kt

@@ -1,6 +1,9 @@
 package com.github.damontecres.dolphin
 
+import android.view.KeyEvent
+import androidx.compose.ui.Modifier
 import androidx.compose.ui.focus.FocusRequester
+import androidx.compose.ui.input.key.onPreviewKeyEvent
 import timber.log.Timber
 import kotlin.contracts.ExperimentalContracts
 import kotlin.contracts.contract
@@ -24,3 +27,61 @@ fun FocusRequester.tryRequestFocus(): Boolean =
         Timber.w(ex, "Failed to request focus")
         false
     }
+
+/**
+ * Used to apply modifiers conditionally.
+ */
+fun Modifier.ifElse(
+    condition: () -> Boolean,
+    ifTrueModifier: Modifier,
+    ifFalseModifier: Modifier = Modifier,
+): Modifier = then(if (condition()) ifTrueModifier else ifFalseModifier)
+
+/**
+ * Used to apply modifiers conditionally.
+ */
+fun Modifier.ifElse(
+    condition: Boolean,
+    ifTrueModifier: Modifier,
+    ifFalseModifier: Modifier = Modifier,
+): Modifier = ifElse({ condition }, ifTrueModifier, ifFalseModifier)
+
+/**
+ * Handles horizontal (Left & Right) D-Pad Keys and consumes the event(s) so that the focus doesn't
+ * accidentally move to another element.
+ * */
+fun Modifier.handleDPadKeyEvents(
+    onLeft: (() -> Unit)? = null,
+    onRight: (() -> Unit)? = null,
+    onCenter: (() -> Unit)? = null,
+    triggerOnAction: Int = KeyEvent.ACTION_UP,
+) = onPreviewKeyEvent {
+    fun onActionUp(block: () -> Unit) {
+        if (it.nativeKeyEvent.action == triggerOnAction) block()
+    }
+
+    when (it.nativeKeyEvent.keyCode) {
+        KeyEvent.KEYCODE_DPAD_LEFT, KeyEvent.KEYCODE_SYSTEM_NAVIGATION_LEFT -> {
+            onLeft?.apply {
+                onActionUp(::invoke)
+                return@onPreviewKeyEvent true
+            }
+        }
+
+        KeyEvent.KEYCODE_DPAD_RIGHT, KeyEvent.KEYCODE_SYSTEM_NAVIGATION_RIGHT -> {
+            onRight?.apply {
+                onActionUp(::invoke)
+                return@onPreviewKeyEvent true
+            }
+        }
+
+        KeyEvent.KEYCODE_DPAD_CENTER, KeyEvent.KEYCODE_ENTER, KeyEvent.KEYCODE_NUMPAD_ENTER -> {
+            onCenter?.apply {
+                onActionUp(::invoke)
+                return@onPreviewKeyEvent true
+            }
+        }
+    }
+
+    false
+}