I am trying to create a calendar view that allows users to select multiple date ranges, including non continuous, continuous, and single dates. I also want to allow users to drag to select date ranges but I am struggling to implement that portion.

I believe the issue is my if statement in the dragSelect function, the original from this thread is commented out below it. I’ve tried using DispatchQueue to see if async timing was the problem but I might have done that wrong, it also seems like rectangles.content[i] = gp.frame(in: .named("container")) could be the problem?. getBackground just sets the background to a certain color if it is contained in the selectedDates set. Any advice is greatly appreciated!!

struct testDrag: View
{
    var rectangles = Rectangles()
    @State var selectRect: CGRect?
    let days = Date.now.calendarDisplayDays
    @State private var date = Date.now
    private var textColor: Color = .black
    private var selectColor: Color = .baseTeal
    let daysOfWeek = Date.capitalizedFirstLettersOfWeekdays
    let columns = Array(repeating: GridItem(.flexible()), count: 7)
    
    @State private var selectedDates: Set<Date> = []
    @State private var selectedCell: CGRect?
    var body: some View
    {
        GeometryReader { geometry in
            ZStack(alignment: .topLeading) {
                LazyVGrid(columns: columns
                          ,content: {
                    ForEach(0..<days.count, id: .self) { i in
                        if days[i].monthInt != date.monthInt {
                            Text("")
                                .frame(maxWidth: geometry.size.width/7, minHeight: 40, alignment: .center)
                        } else {
                            Text(days[i].formatted(.dateTime.day()))
                                .fontWeight(.medium)
                                .frame(minWidth: (geometry.size.width/7) - 3, minHeight: 40, alignment: .center)
                                .background(getBackground(for: days[i]))
                            
                                .background() {
                                    GeometryReader { gp -> Color in
                                        rectangles.content[i] = gp.frame(in: .named("container"))
                                        
                                        return Color.clear
                                    }
                                }
                            
                                .cornerRadius(20)
                                .onTapGesture {
                                    if selectedDates.contains(days[i].startOfDay) {
                                        selectedDates.remove(days[i].startOfDay)
                                    }
                                    else {
                                        selectedDates.insert(days[i].startOfDay)
                                    }
                                }
                                .foregroundColor(
                                    selectedDates.contains(days[i].startOfDay) ? textColor :
                                        (Date.now.startOfDay == days[i].startOfDay ? selectColor : textColor)
                                )
                        }
                    }
                })
                .coordinateSpace(name: "container")
                .gesture(dragSelect)
                
                if let selR = selectRect {
                    Rectangle()
                        .frame(width: selR.width, height: selR.height)
                        .offset(x: selR.origin.x, y: selR.origin.y)
                }
            }
        }
    }
    
    private var dragSelect: some Gesture
    {
        DragGesture(minimumDistance: 2)
            .onChanged { drag in
                    let a = drag.startLocation
                    let b = drag.location
                    
                    self.selectRect = CGRect(x: min(a.x, b.x), y: min(a.y, b.y), width: abs(a.x - b.x), height: abs(a.y - b.y))
                    
                    var resSet = Set<Date>()
                    for i in 0 ..< self.days.count {
                        if let rect = self.rectangles.content[i], ((self.selectRect?.intersects(rect)) != nil) {
                        // if CGRectIntersectsRect(rectangles.content[i]!, selectRect!) {

                            resSet.insert(days[i])
                            
                        }
                    self.selectedDates = resSet
                }
            }
            .onEnded { _ in
                    self.selectRect = nil
            }
    }
}

class Rectangles
{
    var content = [Int : CGRect]()
}