🚧 First draw of colored days in calendar

AboTracker/Subscription.swift

@@ -57,6 +57,41 @@ final class Subscription: Identifiable {
         }
         return remaining
     }
+    
+    func getPaymentDaysIn(year: Int, month: Int) -> [Int] {
+        var paymentDays: [Int] = []
+        
+        let calendar = Calendar.current
+        let components = DateComponents(year: year, month: month)
+        guard let date = calendar.date(from: components) else {
+            return paymentDays
+        }
+        
+        for payment in payments {
+            var currentDate = payment.startDate
+            while calendar.isDate(currentDate, equalTo: date, toGranularity: .month) {
+                let day = calendar.component(.day, from: currentDate)
+                paymentDays.append(day)
+                
+                switch payment.intervall {
+                case .weekly:
+                    guard let nextDate = calendar.date(byAdding: .day, value: 7, to: currentDate) else { break }
+                    currentDate = nextDate
+                case .monthly:
+                    guard let nextDate = calendar.date(byAdding: .month, value: 1, to: currentDate) else { break }
+                    currentDate = nextDate
+                case .quarter:
+                    guard let nextDate = calendar.date(byAdding: .month, value: 3, to: currentDate) else { break }
+                    currentDate = nextDate
+                case .yearly:
+                    guard let nextDate = calendar.date(byAdding: .year, value: 1, to: currentDate) else { break }
+                    currentDate = nextDate
+                }
+            }
+        }
+        
+        return paymentDays
+    }
 }
 
 final class Payment: Identifiable {

AboTracker/views/ContentView.swift

@@ -1,20 +1,39 @@
 import SwiftUI
 
 struct ContentView: View {
+    @State private var subs: [Subscription] = []
+    
+    init() {
+        self._subs = State(initialValue: [
+            Subscription(name: "Test", payments: [Payment(amount: 9.99, intervall: .monthly, startDate: getDate(from: "2023-01-01"))], color: .blue),
+            Subscription(name: "Fitness First", payments: [
+                Payment(amount: 7.9, intervall: .weekly, startDate: getDate(from: "2023-01-23")),
+                Payment(amount: 29, intervall: .quarter, startDate: getDate(from: "2023-04-03"))
+            ], color: .red)
+        ])
+    }
+    
     var body: some View {
         TabView {
-            HomeView()
+            HomeView(subs: $subs)
                 .tabItem {
                     Image(systemName: "house.fill")
                     Text("Home")
                 }
 
-            PaymentCalendarView()
+            PaymentCalendarView(subs: $subs)
                 .tabItem {
                     Image(systemName: "calendar")
                     Text("Calendar")
                 }
         }
+        .background(Color.gray.opacity(0.2))
+    }
+    
+    private func getDate(from dateString: String) -> Date {
+        let formatter = DateFormatter()
+        formatter.dateFormat = "yyyy-MM-dd"
+        return formatter.date(from: dateString) ?? Date()
     }
 }
 

AboTracker/views/HomeView.swift

@@ -1,18 +1,8 @@
 import SwiftUI
 
 struct HomeView: View {
+    @Binding var subs: [Subscription]
     @State private var showAddSubscriptionSheet = false
-    @State private var subs: [Subscription] = []
-    
-    init() {
-        self._subs = State(initialValue: [
-            Subscription(name: "Test", payments: [Payment(amount: 9.99, intervall: .monthly, startDate: self.getDate(from: "2023-01-01"))], color: .blue),
-            Subscription(name: "Fitness First", payments: [
-                Payment(amount: 7.9, intervall: .weekly, startDate: self.getDate(from: "2023-01-23")),
-                Payment(amount: 29, intervall: .quarter, startDate: self.getDate(from: "2023-04-03"))
-            ], color: .red)
-        ])
-    }
     
     var body: some View {
         NavigationView {
@@ -105,22 +95,16 @@ struct HomeView: View {
         }
         return remainingTotal
     }
-    
-    func getDate(from dateString: String) -> Date {
-        let formatter = DateFormatter()
-        formatter.dateFormat = "yyyy-MM-dd"
-        return formatter.date(from: dateString) ?? Date()
-    }
-    
-    func formattedDate(_ date: Date) -> String {
-        let formatter = DateFormatter()
-        formatter.dateStyle = .medium
-        return formatter.string(from: date)
-    }
 }
 
 struct HomeView_Previews: PreviewProvider {
     static var previews: some View {
-        HomeView()
+        HomeView(subs: .constant([
+            Subscription(name: "Test", payments: [Payment(amount: 9.99, intervall: .monthly, startDate: Date())], color: .blue),
+            Subscription(name: "Fitness First", payments: [
+                Payment(amount: 7.9, intervall: .weekly, startDate: Date()),
+                Payment(amount: 29, intervall: .quarter, startDate: Date())
+            ], color: .red)
+        ]))
     }
 }

AboTracker/views/PaymentCalendarView.swift

@@ -1,18 +1,131 @@
 import SwiftUI
 
 struct PaymentCalendarView: View {
+    @Binding var subs: [Subscription]
+    let calendar = Calendar.current
+    let dateFormatter = DateFormatter()
+    
+    @State private var currentDate = Date()
+    
     var body: some View {
         VStack {
             Text("Payment Calendar")
                 .font(.title)
                 .padding()
-            Spacer()
+            
+            Text(currentMonthYear())
+                .font(.headline)
+                .padding()
+            
+            calendarView()
         }
+        .padding()
+    }
+    
+    func currentMonthYear() -> String {
+        let formatter = DateFormatter()
+        formatter.dateFormat = "MMMM yyyy"
+        return formatter.string(from: currentDate)
+    }
+    
+    func calendarView() -> some View {
+        let days = daysInMonth(date: currentDate)
+        let firstDay = firstDayOfMonth(date: currentDate)
+        
+        let columns = Array(repeating: GridItem(.flexible()), count: 7)
+        let weeks = (days.count + firstDay) / 7 + ((days.count + firstDay) % 7 == 0 ? 0 : 1)
+        
+        return LazyVGrid(columns: columns, spacing: 20) {
+            ForEach(0..<7, id: \.self) { index in
+                Text(daySymbol(index: index))
+                    .fontWeight(.bold)
+            }
+            
+            ForEach(0..<(weeks * 7), id: \.self) { index in
+                if index < firstDay || index - firstDay >= days.count {
+                    Text("")
+                } else {
+                    let day = index - firstDay + 1
+                    let dayDate = calendar.date(byAdding: .day, value: day - 1, to: startOfMonth(date: currentDate))!
+                    let paymentColor = getPaymentColor(for: dayDate)
+                    
+                    Text("\(day)")
+                        .frame(maxWidth: .infinity, maxHeight: .infinity)
+                        .background(paymentColor)
+                        .cornerRadius(8)
+                }
+            }
+        }
+    }
+    
+    func getPaymentColor(for date: Date) -> Color {
+        for sub in subs {
+            for payment in sub.payments {
+                if isPaymentDue(payment: payment, for: date) {
+                    return sub.color.opacity(0.3)
+                }
+            }
+        }
+        return Color.clear
+    }
+    
+    func isPaymentDue(payment: Payment, for date: Date) -> Bool {
+        switch payment.intervall {
+        case .weekly:
+            let startOfWeek = calendar.date(from: calendar.dateComponents([.yearForWeekOfYear, .weekOfYear], from: date))!
+            let endOfWeek = calendar.date(byAdding: .day, value: 6, to: startOfWeek)!
+            return date >= startOfWeek && date <= endOfWeek && calendar.component(.weekday, from: payment.startDate) == calendar.component(.weekday, from: date)
+            
+        case .monthly:
+            // ToDo: Payment not visible if Payment is at example at 31th of month, but month only has 30 days
+            return calendar.component(.day, from: payment.startDate) == calendar.component(.day, from: date)
+            
+        case .quarter:
+            guard let quarterStartDate = calendar.date(byAdding: .month, value: -3, to: payment.startDate) else {
+                return false
+            }
+            let startOfQuarter = calendar.date(from: calendar.dateComponents([.year, .month], from: quarterStartDate))!
+            let endOfQuarter = calendar.date(byAdding: .month, value: 3, to: startOfQuarter)!
+            return date >= startOfQuarter && date <= endOfQuarter
+        
+        case .yearly:
+            return calendar.component(.year, from: payment.startDate) == calendar.component(.year, from: date)
+        }
+    }
+
+    func daysInMonth(date: Date) -> [Date] {
+        guard let range = calendar.range(of: .day, in: .month, for: date) else { return [] }
+        return range.compactMap { day -> Date? in
+            var components = calendar.dateComponents([.year, .month], from: date)
+            components.day = day
+            return calendar.date(from: components)
+        }
+    }
+    
+    func firstDayOfMonth(date: Date) -> Int {
+        let components = calendar.dateComponents([.year, .month], from: date)
+        guard let firstDay = calendar.date(from: components) else { return 0 }
+        return calendar.component(.weekday, from: firstDay) - calendar.firstWeekday
+    }
+    
+    func daySymbol(index: Int) -> String {
+        dateFormatter.shortWeekdaySymbols[(index + calendar.firstWeekday - 1) % 7]
+    }
+    
+    func startOfMonth(date: Date) -> Date {
+        let components = calendar.dateComponents([.year, .month], from: date)
+        return calendar.date(from: components) ?? date
     }
 }
 
 struct PaymentCalendarView_Previews: PreviewProvider {
     static var previews: some View {
-        PaymentCalendarView()
+        PaymentCalendarView(subs: .constant([
+            Subscription(name: "Test", payments: [Payment(amount: 9.99, intervall: .monthly, startDate: Date())], color: .blue),
+            Subscription(name: "Fitness First", payments: [
+                Payment(amount: 7.9, intervall: .weekly, startDate: Date()),
+                Payment(amount: 29, intervall: .quarter, startDate: Date())
+            ], color: .red)
+        ]))
     }
 }