case invalid(msg: String)

case unsupported(msg: String)

public var errorDescription: String? {

switch self {

case .invalid(msg: let msg):

"URL was invalid: \(msg)"

case .unsupported(msg: let msg):

"Operation not supported: \(msg)"

}

}

public var failureReason: String? { "Unable to parse URL" }

guard url.scheme == "otpauth" || url.scheme == "ovault-otpauth" else { throw URLParseError.unsupported(msg: "Only otpauth URLs are supported.") }

let components = url.pathComponents

guard components.count == 2 else { throw URLParseError.invalid(msg: "Expected 2 path components (including /).") }

guard let type = url.host(), type == "totp" else { throw URLParseError.unsupported(msg: "Currently only TOTPs are supported.") }

guard let label = components[1].removingPercentEncoding else { throw URLParseError.invalid(msg: "Unable to parse first part of the URL.") }

let labelParts = label.split(separator: ":")

var issuer: String? = if labelParts.count == 2 { String(labelParts[0]) } else { nil }

let accountName = if labelParts.count == 2 { String(labelParts[1]) } else { String(labelParts[0]) }

guard let query = url.queryParameters else { throw URLParseError.invalid(msg: "Expected query parameters.") }

guard let secret = query["secret"] else { throw URLParseError.invalid(msg: "A shared secret is expected.") }

if let queryIssuer = query["issuer"] {

issuer = queryIssuer

}

guard let issuer else { throw URLParseError.invalid(msg: "Expected an Issuer to be specified in the URL.") }

let algorithm = if let queryAlgorithm = query["algorithm"] { HashAlgorithm(rawValue: queryAlgorithm) } else { HashAlgorithm.SHA1 }

let digits = Int(query["digits"] ?? "6") ?? 6

let period = Int(query["period"] ?? "30") ?? 30

let domainName = issuer.contains(".") ? issuer : "\(issuer).com"

return .init(id: UUID(), issuer: issuer, accountName: accountName, domainName: domainName, algorithm: algorithm ?? .SHA1, digits: digits, secret: secret, period: period)

guard

let components = URLComponents(url: self, resolvingAgainstBaseURL: true),

let queryItems = components.queryItems else { return nil }

return queryItems.reduce(into: [String: String]()) { (result, item) in

result[item.name] = item.value

}