mycode/myApp/Expiranner/IOS/Theme.swift

import SwiftUI
import UIKit

// MARK: - 색상 팔레트 (라이트/다크 자동 전환)

extension Color {
    init(hex: UInt32) {
        self.init(
            .sRGB,
            red: Double((hex >> 16) & 0xFF) / 255,
            green: Double((hex >> 8) & 0xFF) / 255,
            blue: Double(hex & 0xFF) / 255
        )
    }

    /// 라이트/다크 모드에 따라 자동으로 전환되는 동적 색.
    /// `.preferredColorScheme`으로 지정한 모드를 그대로 따른다.
    static func dynamic(light: Color, dark: Color) -> Color {
        Color(UIColor { trait in
            trait.userInterfaceStyle == .dark ? UIColor(dark) : UIColor(light)
        })
    }
}

enum Theme {
    static let bg = Color.dynamic(light: Color(hex: 0xF2F4F7), dark: Color(hex: 0x0B0E13))
    static let surface = Color.dynamic(light: Color(hex: 0xFFFFFF), dark: Color(hex: 0x161B25))
    static let surfaceHi = Color.dynamic(light: Color(hex: 0xE9EDF3), dark: Color(hex: 0x202836))
    static let stroke = Color.dynamic(light: .black.opacity(0.08), dark: .white.opacity(0.07))

    // 텍스트/테두리로 쓰이므로 라이트 모드에서는 대비를 위해 더 진한 민트.
    static let accent = Color.dynamic(light: Color(hex: 0x0FA06E), dark: Color(hex: 0x3BE39F))
    static let accentSoft = Color.dynamic(
        light: Color(hex: 0x0FA06E).opacity(0.12),
        dark: Color(hex: 0x3BE39F).opacity(0.14)
    )
    // 밝은 accentGradient 위에 얹는 어두운 글자색 (두 모드 공통).
    static let onAccent = Color(hex: 0x07281B)

    static let danger = Color.dynamic(light: Color(hex: 0xD64545), dark: Color(hex: 0xFF7A7A))
    static let warn = Color.dynamic(light: Color(hex: 0xB77E00), dark: Color(hex: 0xFFC94D))
    static let sunday = Color.dynamic(light: Color(hex: 0xD64C42), dark: Color(hex: 0xFF8A80))
    static let saturday = Color.dynamic(light: Color(hex: 0x3568C4), dark: Color(hex: 0x7EB6FF))

    static let textPrimary = Color.dynamic(light: Color(hex: 0x1A1E26), dark: Color(hex: 0xF3F6FA))
    static let textSecondary = Color.dynamic(light: Color(hex: 0x687285), dark: Color(hex: 0x8D99AD))

    // 밝은 민트 그라디언트 — 두 모드 공통(위에 onAccent 어두운 글자).
    static let accentGradient = LinearGradient(
        colors: [Color(hex: 0x5CF0B6), Color(hex: 0x1FC98B)],
        startPoint: .topLeading,
        endPoint: .bottomTrailing
    )
}

// MARK: - 화면 모드 설정

/// 사용자가 고를 수 있는 외관 모드. `@AppStorage(appearanceStorageKey)`에 raw 값으로 저장.
enum AppearanceMode: Int, CaseIterable, Identifiable {
    case system = 0
    case light = 1
    case dark = 2

    var id: Int { rawValue }

    var title: String {
        switch self {
        case .system: return "시스템"
        case .light: return "라이트"
        case .dark: return "다크"
        }
    }

    var icon: String {
        switch self {
        case .system: return "iphone"
        case .light: return "sun.max.fill"
        case .dark: return "moon.fill"
        }
    }

    var colorScheme: ColorScheme? {
        switch self {
        case .system: return nil
        case .light: return .light
        case .dark: return .dark
        }
    }
}

/// 외관 모드 저장 키. 기본값은 기존 동작 유지를 위해 `.dark`.
let appearanceStorageKey = "appearanceMode"

// MARK: - 공용 스타일

struct CardBackground: ViewModifier {
    var cornerRadius: CGFloat = 18

    func body(content: Content) -> some View {
        content
            .background(
                RoundedRectangle(cornerRadius: cornerRadius, style: .continuous)
                    .fill(Theme.surface)
                    .overlay(
                        RoundedRectangle(cornerRadius: cornerRadius, style: .continuous)
                            .strokeBorder(Theme.stroke, lineWidth: 1)
                    )
            )
    }
}

extension View {
    func cardStyle(cornerRadius: CGFloat = 18) -> some View {
        modifier(CardBackground(cornerRadius: cornerRadius))
    }
}

// MARK: - 햅틱

enum Haptics {
    static func success() { UINotificationFeedbackGenerator().notificationOccurred(.success) }
    static func warning() { UINotificationFeedbackGenerator().notificationOccurred(.warning) }
    static func tap() { UIImpactFeedbackGenerator(style: .light).impactOccurred() }
    static func shutter() { UIImpactFeedbackGenerator(style: .medium).impactOccurred() }
}

// MARK: - 달력 유틸

enum KoreanCalendar {
    static let calendar: Calendar = {
        var c = Calendar(identifier: .gregorian)
        c.locale = Locale(identifier: "ko_KR")
        return c
    }()

    static let weekdaySymbols = ["일", "월", "화", "수", "목", "금", "토"]

    /// 해당 월의 그리드 셀 배열. 앞쪽 빈칸은 nil, 이후 1...말일.
    static func gridDays(year: Int, month: Int) -> [Int?] {
        let comps = DateComponents(year: year, month: month, day: 1)
        guard let first = calendar.date(from: comps),
              let range = calendar.range(of: .day, in: .month, for: first) else { return [] }
        let firstWeekday = calendar.component(.weekday, from: first)
        let leading = (firstWeekday - calendar.firstWeekday + 7) % 7
        return Array(repeating: nil, count: leading) + range.map { $0 }
    }

    static func date(year: Int, month: Int, day: Int) -> Date? {
        calendar.date(from: DateComponents(year: year, month: month, day: day))
    }

    static func isToday(year: Int, month: Int, day: Int) -> Bool {
        let t = calendar.dateComponents([.year, .month, .day], from: .now)
        return t.year == year && t.month == month && t.day == day
    }

    /// 오늘부터 해당 날짜까지 남은 일수 (음수면 지난 날짜)
    static func daysFromToday(to date: Date) -> Int {
        let today = calendar.startOfDay(for: .now)
        let target = calendar.startOfDay(for: date)
        return calendar.dateComponents([.day], from: today, to: target).day ?? 0
    }

    static func weekdayColor(columnIndex: Int) -> Color {
        switch columnIndex {
        case 0: return Theme.sunday
        case 6: return Theme.saturday
        default: return Theme.textSecondary
        }
    }
}

// MARK: - 이미지 유틸

extension UIImage {
    func downscaled(maxDimension: CGFloat) -> UIImage {
        let longest = max(size.width, size.height)
        guard longest > maxDimension, longest > 0 else { return self }
        let ratio = maxDimension / longest
        let newSize = CGSize(width: size.width * ratio, height: size.height * ratio)
        let format = UIGraphicsImageRendererFormat.default()
        format.scale = 1
        return UIGraphicsImageRenderer(size: newSize, format: format).image { _ in
            draw(in: CGRect(origin: .zero, size: newSize))
        }
    }
}