Implement showing authentication progress

app/src/main/java/gq/kirmanak/mealient/ui/OperationUiState.kt

@@ -0,0 +1,38 @@
+package gq.kirmanak.mealient.ui
+
+import android.widget.Button
+import android.widget.ProgressBar
+import androidx.core.view.isVisible
+
+sealed class OperationUiState<T> {
+
+    val exceptionOrNull: Throwable?
+        get() = (this as? Failure)?.exception
+
+    val isSuccess: Boolean
+        get() = this is Success
+
+    val isProgress: Boolean
+        get() = this is Progress
+
+    fun updateButtonState(button: Button) {
+        button.isEnabled = !isProgress
+        button.isClickable = !isProgress
+    }
+
+    fun updateProgressState(progressBar: ProgressBar) {
+        progressBar.isVisible = isProgress
+    }
+
+    class Initial<T> : OperationUiState<T>()
+
+    class Progress<T> : OperationUiState<T>()
+
+    data class Failure<T>(val exception: Throwable) : OperationUiState<T>()
+
+    data class Success<T>(val value: T) : OperationUiState<T>()
+
+    companion object {
+        fun <T> fromResult(result: Result<T>) = result.fold({ Success(it) }, { Failure(it) })
+    }
+}