moodlit-native/Sources/Core/Sync/WidgetSnapshot.swift

import Foundation

/// Schreib-Lese-Bridge zwischen App und Widget-Extension via shared
/// App-Group-UserDefaults.
///
/// Die App schreibt nach jedem `MoodStore.loadAll`-Refresh und nach
/// `toggleFavorite`; das Widget liest in seinem Timeline-Provider.
///
/// Bewusst flach gehalten: kein SwiftData / kein Core Data — ein
/// Codable-Dokument in einem Key reicht für ~10 Favoriten + Last-
/// Played. Größenlimit App-Group-UserDefaults ist locker genug.
public struct WidgetSnapshot: Codable, Equatable, Sendable {
	public let favorites: [WidgetMood]
	public let lastPlayed: WidgetMood?
	public let updatedAt: Date

	public static let appGroup = "group.ev.mana.moodlit"
	public static let storageKey = "moodlit.widgetSnapshot"

	public init(favorites: [WidgetMood], lastPlayed: WidgetMood?, updatedAt: Date = Date()) {
		self.favorites = favorites
		self.lastPlayed = lastPlayed
		self.updatedAt = updatedAt
	}
}

/// Minimal-Repräsentation für Widgets. Hex-Strings statt SwiftUI
/// Color (Widget-Process kann keine `Color` aus App-Bundle-Resources
/// dereferenzieren) und nur der Animation-Slug.
public struct WidgetMood: Codable, Equatable, Identifiable, Sendable {
	public let id: String
	public let name: String
	public let colors: [String]
	public let animation: String

	public init(id: String, name: String, colors: [String], animation: String) {
		self.id = id
		self.name = name
		self.colors = colors
		self.animation = animation
	}
}

/// Lesen/Schreiben des Snapshots aus dem App-Group-Container.
/// Beide Seiten (App + Widget) konsumieren `WidgetSnapshot.appGroup`.
public enum WidgetSnapshotStore {
	private static var defaults: UserDefaults? {
		UserDefaults(suiteName: WidgetSnapshot.appGroup)
	}

	public static func read() -> WidgetSnapshot? {
		guard let data = defaults?.data(forKey: WidgetSnapshot.storageKey) else { return nil }
		return try? JSONDecoder().decode(WidgetSnapshot.self, from: data)
	}

	public static func write(_ snapshot: WidgetSnapshot) {
		guard let data = try? JSONEncoder().encode(snapshot) else { return }
		defaults?.set(data, forKey: WidgetSnapshot.storageKey)
	}

	public static func clear() {
		defaults?.removeObject(forKey: WidgetSnapshot.storageKey)
	}
}