[DON-715] Add capabilities to BPKcalendar required for wholeMonth s…

…election (#2104)

* DON-628 / Whole month selection as a separate category in Backpack

* DON-628 / Make whole month selection as part of range stage in Backpack calendar

* DON-628 / Move the calendar month selection logic to Backpack calendar

* Remove CalendarMonth data entity to simplifies

* DON-628 / Remove redundant file

* Remove extra condition on accessibility traits

* Fix lint issues

* Remove extra file

* Add example in Calendar SwiftUI about whole month selection

* Make accessory action based on given date

* Fix the example app

* Change the order of examples

* Improve the comments and file names

* Make highlight parameter explicit based on PR feedbacks

* Make calendar accessory action as enum.

* Fix the linting issue

* Fix the tests

Backpack-SwiftUI/Calendar/Classes/BPKCalendar.swift

@@ -37,8 +37,8 @@ public struct BPKCalendar<DayAccessoryView: View>: View {
     let calendar: Calendar
     let selectionType: CalendarSelectionType
     let validRange: ClosedRange<Date>
+    private var accessoryAction: ((Date) -> CalendarMonthAccessoryAction?)?
     private var initialMonthScroll: MonthScroll?
-    private var accessoryAction: CalendarMonthAccessoryAction?
     private let monthHeaderDateFormatter: DateFormatter
 
     private let dayAccessoryView: (Date) -> DayAccessoryView
@@ -82,6 +82,7 @@ public struct BPKCalendar<DayAccessoryView: View>: View {
                                 monthDate: monthDate,
                                 dateFormatter: monthHeaderDateFormatter,
                                 calendar: calendar,
+                                validRange: validRange,
                                 accessoryAction: accessoryAction,
                                 currentlyShownMonth: $currentlyShownMonth,
                                 parentProxy: calendarProxy
@@ -106,8 +107,8 @@ public struct BPKCalendar<DayAccessoryView: View>: View {
         }
     }
 
-    /// Sets the accessory action for the calendar to be applied to each month.
-    public func monthAccessoryAction(_ action: CalendarMonthAccessoryAction) -> BPKCalendar {
+    /// Sets the accessory action for the calendar to be applied to each month, based on the give month `Date`.
+    public func monthAccessoryAction(_ action: ((Date) -> CalendarMonthAccessoryAction?)?) -> BPKCalendar {
         var result = self
         result.accessoryAction = action
         return result
@@ -142,6 +143,8 @@ struct BPKCalendar_Previews: PreviewProvider {
                 BPKText("20", style: .caption)
             }
         )
-        .monthAccessoryAction(CalendarMonthAccessoryAction(title: "Select whole month", action: { _ in }))
+        .monthAccessoryAction { _ in
+            return CalendarMonthAccessoryAction(title: "Select whole month", action: .custom({ _ in }))
+        }
     }
 }

Backpack-SwiftUI/Calendar/Classes/CalendarMonthAccessoryAction.swift

@@ -22,14 +22,24 @@ import SwiftUI
 ///     be performed when a user interacts with an accessory in the calendar.
 public struct CalendarMonthAccessoryAction {
     let title: String
-    let action: (Date) -> Void
+    let action: Action
 
     /// - Parameters:
     ///  - title: The title of the accessory.
     ///  - action: The action to be performed when the user interacts with the accessory.
-    ///           This closure takes a `Date` as a parameter, which is the date that the user interacted with.
-    public init(title: String, action: @escaping (Date) -> Void) {
+    public init(title: String, action: Action) {
         self.title = title
         self.action = action
     }
+
+    /// Defines the types of actions that can be triggered.
+    public enum Action {
+        /// A custom action triggered for a specific date month.
+        /// - Parameter: The `Date` representing the month interacted with by the user.
+        case custom((Date) -> Void)
+
+        /// An action triggered for a whole month selection.
+        /// - Parameter: A `ClosedRange<Date>` for the start and end of the selected month (calendar range considered).
+        case wholeMonthSelection((ClosedRange<Date>) -> Void)
+    }
 }

Backpack-SwiftUI/Calendar/Classes/CalendarMonthHeader.swift

@@ -24,7 +24,8 @@ struct CalendarMonthHeader: View {
     let monthDate: Date
     let dateFormatter: DateFormatter
     let calendar: Calendar
-    let accessoryAction: CalendarMonthAccessoryAction?
+    let validRange: ClosedRange<Date>
+    let accessoryAction: ((Date) -> CalendarMonthAccessoryAction?)?
     @Binding var currentlyShownMonth: Date
     let parentProxy: GeometryProxy
 
@@ -41,17 +42,34 @@ struct CalendarMonthHeader: View {
                 }
             }
             .frame(width: 1)
-            if let accessoryAction {
-                BPKButton(accessoryAction.title) {
-                    accessoryAction.action(monthDate)
+            if let accessory = accessoryAction?(monthDate) {
+                BPKButton(accessory.title) {
+                    switch accessory.action {
+                    case .custom(let action):
+                        action(monthDate)
+                    case .wholeMonthSelection(let action):
+                        guard let range = monthRangeFor(date: monthDate) else { return }
+                        action(range)
+                    }
                 }
                 .buttonStyle(.link)
             }
         }
         .padding(.horizontal, .base)
         .padding(.vertical, .lg)
     }
-
+
+    private func monthRangeFor(date: Date) -> ClosedRange<Date>? {
+        guard let monthRange = date.getMonthDateRange(calendar: calendar) else {
+            return nil
+        }
+
+        let lowerBound = max(validRange.lowerBound, monthRange.lowerBound)
+        let upperBound = min(validRange.upperBound, monthRange.upperBound)
+
+        return lowerBound...upperBound
+    }
+
     private func isCurrentlyShowingMonth(proxy: GeometryProxy) -> Bool {
         let parentGlobalFrame = parentProxy.frame(in: .global)
         let yParentOrigin = parentGlobalFrame.origin.y
@@ -69,14 +87,20 @@ struct CalendarMonthHeader_Previews: PreviewProvider {
         dateFormatter.dateFormat = "MMMM yyyy"
         return dateFormatter
     }()
-    
+
     static var previews: some View {
+        let calendar = Calendar.current
+
+        let start = calendar.date(from: .init(year: 2023, month: 10, day: 1))!
+        let end = calendar.date(from: .init(year: 2025, month: 12, day: 25))!
+
         GeometryReader { proxy in
             CalendarMonthHeader(
                 monthDate: Date(),
                 dateFormatter: Self.dateFormatter,
                 calendar: Calendar.current,
-                accessoryAction: .init(title: "Action", action: { _ in }),
+                validRange: start...end,
+                accessoryAction: { _ in return .init(title: "Action", action: .custom({ _ in })) },
                 currentlyShownMonth: .constant(Date()),
                 parentProxy: proxy
             )

Backpack-SwiftUI/Calendar/Classes/CalendarRangeSelectionState.swift

@@ -25,4 +25,7 @@ public enum CalendarRangeSelectionState {
 
     /// The final state, where the user has selected both dates of the range.
     case range(ClosedRange<Date>)
+
+    /// The state the user has selected the whole month range.
+    case wholeMonth(ClosedRange<Date>)
 }

Backpack-SwiftUI/Calendar/Classes/Core/CalendarTypeContainerFactory.swift

@@ -48,9 +48,9 @@ struct CalendarTypeContainerFactory<MonthHeader: View, DayAccessoryView: View>:
                 monthHeader: monthHeader,
                 dayAccessoryView: dayAccessoryView
             )
-        case .single(let selected, let accessibilityConfigurations):
+        case .single(let selection, let accessibilityConfigurations):
             SingleCalendarContainer(
-                selection: selected,
+                selection: selection,
                 calendar: calendar,
                 validRange: validRange,
                 accessibilityProvider: SingleDayAccessibilityProvider(
@@ -61,6 +61,7 @@ struct CalendarTypeContainerFactory<MonthHeader: View, DayAccessoryView: View>:
                 monthHeader: monthHeader,
                 dayAccessoryView: dayAccessoryView
             )
+
         }
     }
 }

Backpack-SwiftUI/Calendar/Classes/Date+GetMonthDateRange.swift

@@ -0,0 +1,56 @@
+/*
+ * Backpack - Skyscanner's Design System
+ *
+ * Copyright 2018 Skyscanner Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import Foundation
+
+extension Date {
+    public func getMonthDateRange(calendar: Calendar) -> ClosedRange<Date>? {
+        let components = calendar.dateComponents([.year, .month], from: self)
+
+        guard let year = components.year, let month = components.month else {
+            return nil
+        }
+
+        // Create DateComponents for the start of the month
+        var startComponents = DateComponents()
+        startComponents.year = year
+        startComponents.month = month
+        startComponents.day = 1
+
+        // Get the start date of the month
+        guard let startDate = calendar.date(from: startComponents) else {
+            return nil
+        }
+
+        // Get the range of days in the month
+        guard let range = calendar.range(of: .day, in: .month, for: startDate) else {
+            return nil
+        }
+
+        // Create the end date of the month
+        let endDay = range.upperBound - 1
+        let endComponents = DateComponents(year: year, month: month, day: endDay)
+
+        guard let endDate = calendar.date(from: endComponents) else {
+            return nil
+        }
+
+        // Return the range of dates
+        return startDate...endDate
+    }
+}

Backpack-SwiftUI/Calendar/Classes/Range/Cells/EmptyRangeSelectionCalendarDayCell.swift

@@ -44,14 +44,14 @@ struct EmptyRangeSelectionCalendarDayCell_Previews: PreviewProvider {
         let endSelection = calendar.date(from: .init(year: 2023, month: 11, day: 10))!
 
         LazyVGrid(columns: Array(repeating: GridItem(spacing: 0), count: 3), spacing: 0) {
-            LowerBoundSelectedCell(calendar: calendar, date: date)
+            LowerBoundSelectedCell(calendar: calendar, date: date, highlighted: true)
             EmptyRangeSelectionCalendarDayCell(
                 cellIndex: 0,
                 correspondingDate: date,
                 selection: startSelection...endSelection
             )
-            UpperBoundSelectedCell(calendar: calendar, date: date)
-            
+            UpperBoundSelectedCell(calendar: calendar, date: date, highlighted: true)
+
         }
     }
 }

Backpack-SwiftUI/Calendar/Classes/Range/Cells/LowerBoundSelectedCell.swift

@@ -21,7 +21,8 @@ import SwiftUI
 struct LowerBoundSelectedCell: View {
     let calendar: Calendar
     let date: Date
-
+    let highlighted: Bool
+
     var body: some View {
         ZStack {
             GeometryReader { proxy in
@@ -30,21 +31,29 @@ struct LowerBoundSelectedCell: View {
                     .offset(x: proxy.size.width / 2)
             }
             BPKText("\(calendar.component(.day, from: date))", style: .label1)
-                .foregroundColor(.textPrimaryInverseColor)
+                .foregroundColor(textColor)
                 .lineLimit(1)
                 .frame(maxWidth: .infinity)
                 .padding(.vertical, .md)
-                .background(.coreAccentColor)
+                .background(circleColor)
                 .clipShape(Circle())
         }
     }
+
+    private var circleColor: BPKColor {
+        highlighted ? .coreAccentColor : .surfaceSubtleColor
+    }
+
+    private var textColor: BPKColor {
+        highlighted ? .textPrimaryInverseColor : .black
+    }
 }
 
 struct LowerBoundSelectedCell_Previews: PreviewProvider {
     static var previews: some View {
         let calendar = Calendar.current
         let date = calendar.date(from: .init(year: 2023, month: 11, day: 8))!
 
-        LowerBoundSelectedCell(calendar: calendar, date: date)
+        LowerBoundSelectedCell(calendar: calendar, date: date, highlighted: true)
     }
 }

Backpack-SwiftUI/Calendar/Classes/Range/Cells/RangeSelectionCalendarDayCell.swift

@@ -22,14 +22,15 @@ struct RangeSelectionCalendarDayCell: View {
     let date: Date
     let selection: ClosedRange<Date>
     let calendar: Calendar
-
+    let highlightRangeEnds: Bool
+
     var body: some View {
         if selection.lowerBound == selection.upperBound {
             LowerAndUpperBoundSelectedCell(calendar: calendar, date: date)
         } else if date == selection.lowerBound {
-            LowerBoundSelectedCell(calendar: calendar, date: date)
+            LowerBoundSelectedCell(calendar: calendar, date: date, highlighted: highlightRangeEnds)
         } else if date == selection.upperBound {
-            UpperBoundSelectedCell(calendar: calendar, date: date)
+            UpperBoundSelectedCell(calendar: calendar, date: date, highlighted: highlightRangeEnds)
         } else {
             InbetweenSelectionCell(calendar: calendar, date: date)
         }
@@ -44,9 +45,9 @@ struct SelectedCalendarDayCell_Previews: PreviewProvider {
         LazyVGrid(columns: Array(repeating: GridItem(spacing: 0), count: 6), spacing: 0) {
             DefaultCalendarDayCell(calendar: calendar, date: date)
             DisabledCalendarDayCell(calendar: calendar, date: date)
-            LowerBoundSelectedCell(calendar: calendar, date: date)
+            LowerBoundSelectedCell(calendar: calendar, date: date, highlighted: true)
             InbetweenSelectionCell(calendar: calendar, date: date)
-            UpperBoundSelectedCell(calendar: calendar, date: date)
+            UpperBoundSelectedCell(calendar: calendar, date: date, highlighted: true)
             LowerAndUpperBoundSelectedCell(calendar: calendar, date: date)
         }
     }

Backpack-SwiftUI/Calendar/Classes/Range/Cells/UpperBoundSelectedCell.swift

@@ -21,29 +21,38 @@ import SwiftUI
 struct UpperBoundSelectedCell: View {
     let calendar: Calendar
     let date: Date
-
+    let highlighted: Bool
+
     var body: some View {
         ZStack {
             GeometryReader { proxy in
                 Color(.surfaceSubtleColor)
                     .frame(width: proxy.size.width / 2)
             }
             BPKText("\(calendar.component(.day, from: date))", style: .label1)
-                .foregroundColor(.textPrimaryInverseColor)
+                .foregroundColor(textColor)
                 .lineLimit(1)
                 .frame(maxWidth: .infinity)
                 .padding(.vertical, .md)
-                .background(.coreAccentColor)
+                .background(circleColor)
                 .clipShape(Circle())
         }
     }
+
+    private var circleColor: BPKColor {
+        highlighted ? .coreAccentColor : .surfaceSubtleColor
+    }
+
+    private var textColor: BPKColor {
+        highlighted ? .textPrimaryInverseColor : .black
+    }
 }
 
 struct UpperBoundSelectedCell_Previews: PreviewProvider {
     static var previews: some View {
         let calendar = Calendar.current
         let date = calendar.date(from: .init(year: 2023, month: 11, day: 8))!
 
-        UpperBoundSelectedCell(calendar: calendar, date: date)
+        UpperBoundSelectedCell(calendar: calendar, date: date, highlighted: true)
     }
 }

Backpack-SwiftUI/Calendar/Classes/Range/RangeCalendarContainer.swift

@@ -65,15 +65,30 @@ struct RangeCalendarContainer<MonthHeader: View, DayAccessoryView: View>: View {
             RangeSelectionCalendarDayCell(
                 date: dayDate,
                 selection: closedRange,
-                calendar: calendar
+                calendar: calendar,
+                highlightRangeEnds: true
+            )
+            .accessibilityLabel(Text(
+                accessibilityProvider.accessibilityLabel(
+                    for: dayDate,
+                    selection: closedRange
+                )
+            ))
+            .accessibility(addTraits: .isSelected)
+        } else if case .wholeMonth(let closedRange) = selectionState, closedRange.contains(dayDate) {
+            RangeSelectionCalendarDayCell(
+                date: dayDate,
+                selection: closedRange,
+                calendar: calendar,
+                highlightRangeEnds: false
             )
             .accessibilityLabel(Text(
                 accessibilityProvider.accessibilityLabel(
                     for: dayDate,
                     selection: closedRange
                 )
             ))
-            .accessibility(addTraits: closedRange.contains(dayDate) ? .isSelected : [])
+            .accessibility(addTraits: .isSelected)
         } else {
             DefaultCalendarDayCell(calendar: calendar, date: dayDate)
                 .accessibilityLabel(Text(