Sync OTG transfer photo list UI

suixinkan/Features/TravelAlbum/OTG/Models/TravelAlbumOTGTransferModels.swift

@@ -31,6 +31,27 @@ struct TravelAlbumOTGPhotoItem: Hashable, Sendable {
     }
 }
 
+/// OTG 传输页半小时维度时间槽。
+struct TravelAlbumOTGTimeSlot: Hashable, Sendable {
+    let id: String
+    let dateLabel: String
+    let slotStartLabel: String
+    let photoCount: Int
+}
+
+/// OTG 传输页左侧时间导航日期分组。
+struct TravelAlbumOTGDateGroup: Hashable, Sendable {
+    let dateLabel: String
+    let slots: [TravelAlbumOTGTimeSlot]
+}
+
+/// OTG 传输页照片列表半小时分段。
+struct TravelAlbumOTGPhotoSection: Hashable, Sendable {
+    let slotId: String
+    let headerTitle: String
+    let photos: [TravelAlbumOTGPhotoItem]
+}
+
 /// OTG 传输页 Tab。
 enum TravelAlbumOTGTransferTab: Int, CaseIterable, Sendable {
     case all
@@ -46,6 +67,130 @@ enum TravelAlbumOTGTransferTab: Int, CaseIterable, Sendable {
     }
 }
 
+extension TravelAlbumOTGPhotoItem {
+    /// 将 Android 同款 `yyyy-MM-dd HH:mm:ss` 拍摄时间转为本地日期。
+    func capturedDate() -> Date? {
+        TravelAlbumOTGTimeGrouping.capturedDate(from: capturedAt)
+    }
+}
+
+extension Array where Element == TravelAlbumOTGPhotoItem {
+    /// 按 Android OTG 页规则构造半小时照片分段。
+    func buildPhotoSections() -> [TravelAlbumOTGPhotoSection] {
+        let pairs = compactMap { photo -> (slotStart: Date, photo: TravelAlbumOTGPhotoItem)? in
+            guard let date = photo.capturedDate() else { return nil }
+            return (TravelAlbumOTGTimeGrouping.halfHourSlotStart(for: date), photo)
+        }
+        let grouped = Dictionary(grouping: pairs, by: \.slotStart)
+        return grouped.keys
+            .sorted(by: >)
+            .map { slotStart in
+                let photos = (grouped[slotStart] ?? [])
+                    .map(\.photo)
+                    .sorted { lhs, rhs in
+                        (lhs.capturedDate() ?? .distantPast) > (rhs.capturedDate() ?? .distantPast)
+                    }
+                return TravelAlbumOTGPhotoSection(
+                    slotId: TravelAlbumOTGTimeGrouping.slotId(for: slotStart),
+                    headerTitle: TravelAlbumOTGTimeGrouping.sectionHeaderTitle(for: slotStart),
+                    photos: photos
+                )
+            }
+    }
+
+    /// 按 Android OTG 页规则构造左侧时间快速导航分组。
+    func buildSidebarGroups() -> [TravelAlbumOTGDateGroup] {
+        var slotCounts: [Date: Int] = [:]
+        for photo in self {
+            guard let date = photo.capturedDate() else { continue }
+            let slotStart = TravelAlbumOTGTimeGrouping.halfHourSlotStart(for: date)
+            slotCounts[slotStart, default: 0] += 1
+        }
+        let groupedByDay = Dictionary(grouping: slotCounts.keys) { slotStart in
+            TravelAlbumOTGTimeGrouping.dayStart(for: slotStart)
+        }
+        return groupedByDay.keys
+            .sorted(by: >)
+            .map { dayStart in
+                let slots = (groupedByDay[dayStart] ?? [])
+                    .sorted(by: >)
+                    .map { slotStart in
+                        TravelAlbumOTGTimeSlot(
+                            id: TravelAlbumOTGTimeGrouping.slotId(for: slotStart),
+                            dateLabel: TravelAlbumOTGTimeGrouping.dateLabel(for: slotStart),
+                            slotStartLabel: TravelAlbumOTGTimeGrouping.timeLabel(for: slotStart),
+                            photoCount: slotCounts[slotStart] ?? 0
+                        )
+                    }
+                return TravelAlbumOTGDateGroup(
+                    dateLabel: TravelAlbumOTGTimeGrouping.dateLabel(for: dayStart),
+                    slots: slots
+                )
+            }
+    }
+}
+
+/// OTG 传输页时间分组格式化工具，对齐 Android 的半小时槽规则。
+enum TravelAlbumOTGTimeGrouping {
+    private static let calendar = Calendar(identifier: .gregorian)
+
+    /// 解析 Android OTG 页面使用的拍摄时间字符串。
+    static func capturedDate(from text: String) -> Date? {
+        let formatter = DateFormatter()
+        formatter.locale = Locale(identifier: "en_US_POSIX")
+        formatter.dateFormat = "yyyy-MM-dd HH:mm:ss"
+        return formatter.date(from: text)
+    }
+
+    /// 计算半小时槽起点。
+    static func halfHourSlotStart(for date: Date) -> Date {
+        let components = calendar.dateComponents([.year, .month, .day, .hour, .minute], from: date)
+        let minute = ((components.minute ?? 0) / 30) * 30
+        return calendar.date(
+            from: DateComponents(
+                year: components.year,
+                month: components.month,
+                day: components.day,
+                hour: components.hour,
+                minute: minute
+            )
+        ) ?? date
+    }
+
+    /// 计算日期起点。
+    static func dayStart(for date: Date) -> Date {
+        calendar.startOfDay(for: date)
+    }
+
+    /// 时间槽唯一标识。
+    static func slotId(for date: Date) -> String {
+        format(date, pattern: "yyyy-MM-dd'T'HH:mm", locale: Locale(identifier: "en_US_POSIX"))
+    }
+
+    /// 主列表分段标题。
+    static func sectionHeaderTitle(for date: Date) -> String {
+        let end = calendar.date(byAdding: .minute, value: 30, to: date) ?? date
+        return "\(dateLabel(for: date)) \(timeLabel(for: date)) - \(timeLabel(for: end))"
+    }
+
+    /// 日期标签。
+    static func dateLabel(for date: Date) -> String {
+        format(date, pattern: "MM月dd日", locale: Locale(identifier: "zh_CN"))
+    }
+
+    /// 时间标签。
+    static func timeLabel(for date: Date) -> String {
+        format(date, pattern: "HH:mm", locale: Locale(identifier: "en_US_POSIX"))
+    }
+
+    private static func format(_ date: Date, pattern: String, locale: Locale) -> String {
+        let formatter = DateFormatter()
+        formatter.locale = locale
+        formatter.dateFormat = pattern
+        return formatter.string(from: date)
+    }
+}
+
 /// 相机照片格式匹配工具，对齐 Android `OtgPhotoFormatMatcher`。
 enum TravelAlbumOTGPhotoFormatMatcher {
     /// 相机照片类型。