30 lines
656 B
Swift
30 lines
656 B
Swift
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import Foundation
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protocol Metadata: Codable {
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static var fileName: String { get }
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static var initial: Self { get }
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}
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extension Metadata {
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static func url(in folder: URL) -> URL {
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folder.appendingPathComponent(fileName)
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}
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static func exists(in folder: URL) -> Bool {
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url(in: folder).exists
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}
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init?(in folder: URL) throws {
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let metadataUrl = Self.url(in: folder)
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guard metadataUrl.exists else {
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try Self.initial.writeJSON(to: metadataUrl)
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print("Created metadata in \(folder)")
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return nil
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}
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try self.init(decodeFrom: metadataUrl)
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}
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}
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