import Foundation

/// JSON snapshot cache of the library at `~/.local/state/tv-anarchy/library.json`.
/// A plain Codable file (a few-hundred-show library fits in memory trivially) —
/// the offline-browsable source of truth when ~/media / black are unreachable.
public enum LibraryStore {
    public static func snapshotURL() -> URL {
        FileManager.default.homeDirectoryForCurrentUser
            .appendingPathComponent(".local/state/tv-anarchy/library.json")
    }

    public static func load() -> LibrarySnapshot? {
        guard let data = try? Data(contentsOf: snapshotURL()) else { return nil }
        let dec = JSONDecoder()
        dec.dateDecodingStrategy = .iso8601
        return try? dec.decode(LibrarySnapshot.self, from: data)
    }

    public static func save(_ snapshot: LibrarySnapshot) {
        let url = snapshotURL()
        try? FileManager.default.createDirectory(at: url.deletingLastPathComponent(),
                                                 withIntermediateDirectories: true)
        let enc = JSONEncoder()
        enc.outputFormatting = [.prettyPrinted, .withoutEscapingSlashes]
        enc.dateEncodingStrategy = .iso8601
        guard let data = try? enc.encode(snapshot) else { return }
        try? data.write(to: url, options: .atomic)
    }
}