import Foundation
import WidgetKit

struct TodayMealData: Codable {
    let lunch: String?
    let dinner: String?
    let lunchLabel: String
    let dinnerLabel: String
    let weekdayName: String
    let updatedAt: Date
}

enum WidgetDataStore {
    static let appGroupID = "group.com.alexandrevazquez.mealmood"
    private static let key = "mealmood.today_meals"

    static func update(plan: WeekPlan?, dishes: [Dish], settings: AppSettings) {
        let today = Date()
        let weekday = Calendar.current.component(.weekday, from: today)
        // weekday: 1=Sun,2=Mon..7=Sat → appDayOfWeek: 0=Mon..6=Sun
        let appDayOfWeek = (weekday + 5) % 7

        let lunchId = plan?.slots.first { $0.dayOfWeek == appDayOfWeek && $0.mealType == MealType.lunch.rawValue }?.dishId
        let dinnerId = plan?.slots.first { $0.dayOfWeek == appDayOfWeek && $0.mealType == MealType.dinner.rawValue }?.dishId

        let lunch = lunchId.flatMap { id in dishes.first { $0.id == id }?.name }
        let dinner = dinnerId.flatMap { id in dishes.first { $0.id == id }?.name }

        let locale = Locale(identifier: settings.languageEnum.resolved().localeIdentifier)
        let formatter = DateFormatter()
        formatter.locale = locale
        formatter.dateFormat = "EEEE"
        let weekdayName = formatter.string(from: today).capitalized(with: locale)

        let data = TodayMealData(
            lunch: lunch,
            dinner: dinner,
            lunchLabel: String(localized: "lunch"),
            dinnerLabel: String(localized: "dinner"),
            weekdayName: weekdayName,
            updatedAt: today
        )

        guard let defaults = UserDefaults(suiteName: appGroupID),
              let encoded = try? JSONEncoder().encode(data) else { return }
        defaults.set(encoded, forKey: key)
        WidgetCenter.shared.reloadAllTimelines()
    }

    static func read() -> TodayMealData? {
        guard let defaults = UserDefaults(suiteName: appGroupID),
              let data = defaults.data(forKey: key) else { return nil }
        return try? JSONDecoder().decode(TodayMealData.self, from: data)
    }
}