workoutsplus/WorkoutsPlus/ItemLibrary.swift

//
//  ContentView.swift
//  WorkoutsPlus
//
//  Created by Felix Förtsch on 10.08.24.
//

import SwiftUI
import SwiftData

struct ItemLibrary: View {
		@Environment(\.modelContext) private var modelContext
		@Query private var items: [Item]
		
		@State private var isPresentingNewItemSheet = false
		
		let initialDataSet = [
				"Pull-up",
				"Push-up",
				"Dips",
				"Rows",
				"Split Squat"
		]
		
		var body: some View {
				NavigationView {
						List {
								ForEach(items) { item in
										NavigationLink(destination: ItemDetailsView(item: item)) {
												Text(item.name)
										}
								}
								.onDelete(perform: deleteItem)
						}
						.onAppear {
								if items.isEmpty {
										loadInitialData(exercises: initialDataSet)
								}
						}
						.toolbar {
								ToolbarItem(placement: .navigationBarTrailing) {
										Button {
												createNewItem()
										} label: {
												Label("Add Exercise", systemImage: "plus")
										}
								}
						}
						.sheet(isPresented: $isPresentingNewItemSheet) {
								let newItem = Item(name: "")
								NavigationView {
										ItemDetailsView(item: newItem, isPresentedAsSheet: true)
												.onDisappear {
														if !newItem.name.isEmpty {
																saveItem(item: newItem)
														}
												}
								}
						}
				}
		}
		
		private func createNewItem() {
				isPresentingNewItemSheet = true
		}
		
		private func saveItem(item: Item) {
				modelContext.insert(item)
				try? modelContext.save()
		}
		
		private func deleteItem(offsets: IndexSet) {
				withAnimation {
						for index in offsets {
								modelContext.delete(items[index])
						}
						try? modelContext.save()
				}
		}
		
		private func loadInitialData(exercises: [String]) {
				var items: [Item] = []
				
				for exercise in exercises {
						let item = Item(name: exercise)
						items.append(item)
				}
				
				for item in items {
						modelContext.insert(item)
				}
				
				try? modelContext.save()
		}
}

#Preview {
		ItemLibrary()
				.modelContainer(for: Item.self, inMemory: true)
}