add minimal workout interface, not linked with exercises yet

WorkoutsPlus/WorkoutLibraryView.swift

@@ -0,0 +1,98 @@
+//
+//  WorkoutLibraryView.swift
+//  WorkoutsPlus
+//
+//  Created by Felix Förtsch on 10.08.24.
+//
+
+import SwiftUI
+import SwiftData
+
+struct WorkoutLibraryView: View {
+		@Environment(\.modelContext) private var modelContext
+		@Query private var workouts: [Workout]
+		
+		@State private var isPresentingNewItemSheet = false
+		
+		let initialDataSet = [
+				"RR",
+				"Minimalist"
+		]
+		
+		var body: some View {
+				NavigationView {
+						List {
+								ForEach(workouts.sorted(by: { $0.name < $1.name })) { workout in
+										NavigationLink(destination: WorkoutDetailsView(workout: workout)) {
+												Text(workout.name)
+										}
+								}
+								.onDelete(perform: deleteWorkout)
+						}
+						.onAppear {
+								if workouts.isEmpty {
+										// TODO: This behaviour puts something into [workouts] whenever(!) it is empty. It's not bound to the first ever start of the app or anything. Check if that's the behaviour we want.
+										loadInitialData(workouts: initialDataSet)
+								}
+						}
+						.toolbar {
+								ToolbarItem(placement: .navigationBarTrailing) {
+										Button {
+												createNewWorkout()
+										} label: {
+												Label("Add Workout", systemImage: "plus")
+										}
+								}
+						}
+						.sheet(isPresented: $isPresentingNewItemSheet) {
+								let newWorkout = Workout(name: "")
+								NavigationView {
+										WorkoutDetailsView(workout: newWorkout, isPresentedAsSheet: true)
+												.onDisappear {
+														if !newWorkout.name.isEmpty {
+																saveWorkout(workout: newWorkout)
+														}
+												}
+								}
+						}
+				}
+		}
+		
+		private func createNewWorkout() {
+				isPresentingNewItemSheet = true
+		}
+		
+		private func saveWorkout(workout: Workout) {
+				modelContext.insert(workout)
+				try? modelContext.save()
+		}
+		
+		private func deleteWorkout(offsets: IndexSet) {
+				withAnimation {
+						for index in offsets {
+								modelContext.delete(workouts[index])
+						}
+						try? modelContext.save()
+				}
+		}
+		
+		private func loadInitialData(workouts: [String]) {
+				var items: [Workout] = []
+				
+				for exercise in workouts {
+						let item = Workout(name: exercise)
+						items.append(item)
+				}
+				
+				for item in items {
+						modelContext.insert(item)
+				}
+				
+				try? modelContext.save()
+		}
+}
+
+#Preview {
+		WorkoutLibraryView()
+				.modelContainer(for: Workout.self, inMemory: true)
+}