View to create/modify a subscription

SubscriptionView.swift

import SwiftData
import SwiftUI

struct SubscriptionView: View {
    
    @Environment(\.dismiss) var dismiss
    @Environment(\.colorScheme) var colorScheme
    @Environment(\.modelContext) private var modelContext
    @Query private var subscriptions: [Subscription]
    @Query private var categories: [Category]
    @AppStorage("preferedCurrencyCode") private var preferedCurrencyCode = Currency.preview.first!.code
    @AppStorage("darkModeSetting") private var darkModeSetting: DarkModeSetting = .system
    
    var subscription: Subscription?
    private var notifications = Notifications()
    
    @FocusState private var focusedNameKeyboard: Bool
    @State private var lastEditedSubscriptionId: UUID?
    @State var name = ""
    @State var category: Category? = nil
    @State var iconName = Icon.emojis.first!
    @State var iconColor = Icon.IconColor.red
    @State var referenceBillDate = Date()
    @State var invoiceTime = InvoiceTime.preview.first!
    @State var currency = Currency.preview.first!
    @State var price = 9.99
    @State var notification = false
    
    @State var showIconView = false
    @State var showExtendedDate = false
    @State var showCycleOption = false
    @State var showPrice = false
    
    let formatter: NumberFormatter = {
        let formatter = NumberFormatter()
        formatter.numberStyle = .decimal
        return formatter
    }()
    
    init(subscription: Subscription? = nil) {
        self.subscription = subscription
    }
    
    var body: some View {
        NavigationView {
            ZStack {
                VStack {
                    Form {
                        Section {
                            HStack {
                                Spacer()
                                Button(action: {
                                    self.focusedNameKeyboard = false
                                    self.showIconView = true
                                }) {
                                    ZStack {
                                        RoundedRectangle(cornerRadius: 25.0)
                                            .fill(Color(iconColor.color))
                                            .frame(width: 80, height: 80)
                                        Text(iconName)
                                            .foregroundStyle(Color.white)
                                            .font(.system(size: 42))
                                    }
                                }
                                Spacer()
                            }.listRowBackground(Color.clear)
                        }
                        Section(footer: Text("Notifications are used to remind you when a subscription cycle is close to an end.", comment: "Footer explaining what are notifications for")) {
                            HStack {
                                Text("Name", comment: "The name of the subscription")
                                    .lineLimit(1)
                                Spacer()
                                TextField("Name", text: $name)
                                    .multilineTextAlignment(.trailing)
                                    .focused($focusedNameKeyboard)
                                    .submitLabel(.next)
                                    .lineLimit(1)
                            }
                            Picker(String(localized: "Category", comment: "The category of the subscription"), selection: $category) {
                                Text("None", comment: "None category").tag(nil as Category?)
                                Divider()
                                ForEach(categories) { category in
                                    Text(category.name).tag(category as Category?)
                                }
                            }
                            Toggle(String(localized: "Notifications", comment: "Notifications of the app"), isOn: $notification)
                                .toggleStyle(.switch)
                                .onChange(of: notification) { _, _ in
                                    withAnimation {
                                        self.focusedNameKeyboard = false
                                        showExtendedDate = false
                                        showCycleOption = false
                                        showPrice = false
                                    }
                                }
                        }
                        Section {
                            HStack {
                                Text("Reference bill", comment: "The referenced bill of the subscription")
                                Spacer()
                                DatePicker("Reference bill", selection: $referenceBillDate, displayedComponents: .date)
                                    .labelsHidden()
                                    .datePickerColor(darkModeSetting, colorScheme, showExtendedDate)
                            }.onTapGesture {
                                withAnimation {
                                    showExtendedDate.toggle()
                                    self.focusedNameKeyboard = false
                                    showCycleOption = false
                                    showPrice = false
                                }
                            }
                            if showExtendedDate {
                                DatePicker(selection: $referenceBillDate, displayedComponents: .date) {
                                    Text("Reference bill", comment: "The referenced bill of the subscription")
                                }
                                .datePickerStyle(.graphical)
                            }
                            Button(action: {
                                withAnimation {
                                    showCycleOption.toggle()
                                    showExtendedDate = false
                                    showPrice = false
                                    self.focusedNameKeyboard = false
                                }
                            }) {
                                HStack {
                                    Text("Billing cycle", comment: "The billing cycle of the subscription")
                                        .foregroundStyle(Color.foreground)
                                    Spacer()
                                    Text(invoiceTime.translateLenght())
                                }
                            }
                            if showCycleOption {
                                HStack {
                                    InvoicePicker(timeBetweenInvoices: $invoiceTime)
                                }
                            }
                            Button(action: {
                                withAnimation {
                                    showPrice.toggle()
                                    showExtendedDate = false
                                    showCycleOption = false
                                    self.focusedNameKeyboard = false
                                }
                            }) {
                                HStack {
                                    Text(subscription == nil ? String(localized: "Start price", comment: "The start price of the subscription") : String(localized: "Current price", comment: "The current price of the subscription"))
                                        .foregroundStyle(Color.foreground)
                                    Spacer()
                                    Text(price, format: .currency(code: currency.code).precision(.fractionLength(2)))
                                }
                            }
                            if showPrice {
                                HStack {
                                    CurrencyPicker(currency: $currency)
                                    TextField("Current price", value: $price, formatter: formatter)
                                        .textFieldStyle(.roundedBorder)
                                        .padding()
                                        .keyboardType(.decimalPad)
                                }
                            }
                        }
                    }
                    .padding(.top, -20)
                    .scrollDismissesKeyboard(.interactively)
                }
                .navigationTitle(subscription == nil ? String(localized: "Add Subscription", comment: "Title for the new subscription page") : String(localized: "Modify Subscription", comment: "Title for the modification page"))
                .navigationBarTitleDisplayMode(.inline)
                .toolbar {
                    ToolbarItem(placement: .cancellationAction) {
                        Button(String(localized: "Cancel", comment: "Button to cancel the addition/modification of a subscription"), role: .cancel) {
                            self.focusedNameKeyboard = false
                            dismiss()
                        }
                    }
                    ToolbarItem(placement: .confirmationAction) {
                        saveButton()
                    }
                }
                .sheet(isPresented: $showIconView) {
                    SubscriptionIconView(iconColor: $iconColor, iconEmoji: $iconName)
                }
            }
            .navigationViewStyle(.stack)
        }
        .onAppear {
            if let subscriptionToEdit = subscription {
                if lastEditedSubscriptionId != subscriptionToEdit.id {
                    name = subscriptionToEdit.name
                    category = subscriptionToEdit.category
                    iconName = subscriptionToEdit.icon.emoji
                    iconColor = subscriptionToEdit.icon.color
                    referenceBillDate = subscriptionToEdit.referenceBillDate
                    invoiceTime = subscriptionToEdit.timeBetweenInvoices
                    currency = subscriptionToEdit.currency
                    price = subscriptionToEdit.getCurrentPrices().first!.price
                    notification = subscriptionToEdit.notifications
                    lastEditedSubscriptionId = subscriptionToEdit.id
                }
            } else {
                name = ""
                category = nil
                iconName = Icon.emojis.first!
                iconColor = Icon.IconColor.red
                referenceBillDate = Date()
                invoiceTime = InvoiceTime(number: 1, lenght: .month)
                currency = Currency.preview.first(where: { $0.code == preferedCurrencyCode })!
                price = 9.99
                notification = false
                lastEditedSubscriptionId = nil
            }
        }
    }
    
    private func saveButton() -> some View {
        return Button(subscription == nil ? String(localized: "Add", comment: "Button to add a subscription") : String(localized: "Edit", comment: "Button to modify a subscription")) {
            if notification {
                UNUserNotificationCenter.current().requestAuthorization(options: [.alert, .badge, .sound]) { (granted, error) in
                    if granted { print("Notification access!") } else { print("No access granted!") }
                }
            }
            save()
            self.focusedNameKeyboard = false
            dismiss()
        }.disabled(name.isEmpty)
    }
    
    private func save() {
        if let subscription {
            subscription.name = name
            subscription.category = category
            subscription.icon.emoji = iconName
            subscription.icon.color = iconColor
            subscription.referenceBillDate = referenceBillDate
            subscription.timeBetweenInvoices = invoiceTime
            subscription.currency = currency
            if (subscription.getCurrentPrices().first!.price != price) {
                subscription.prices.append(Prices(startDate: Date(), price: price))
            }
            subscription.notifications = notification
            if subscription.notificationID != "" {
                notifications.removeScheduledNotification(notificationID: subscription.notificationID)
            }
            if notification {
                subscription.notificationID = notifications.scheduleNotification(subscription: subscription)
            }
            do {
                try modelContext.save()
            } catch {
                print("Error when ModelContext is saved: \(error.localizedDescription)")
            }
        } else {
            let newSubscription = Subscription(icon: Icon(color: iconColor, emoji: iconName), name: name, category: category, referenceBillDate: referenceBillDate, timeBetweenInvoices: invoiceTime, currency: currency, notifications: notification, notificationID: "")
            modelContext.insert(newSubscription)
            newSubscription.prices.append(Prices(startDate: Date(), price: price))
            if notification {
                newSubscription.notificationID = notifications.scheduleNotification(subscription: newSubscription)
            }
            do {
                try modelContext.save()
            } catch {
                print("Error when ModelContext is saved: \(error.localizedDescription)")
            }
        }
        dismiss()
    }
}