import MobileNebula

enum APIClientError: Error {
    case invalidCredentials
}

class APIClient {
    let apiClient: MobileNebulaAPIClient
    let json = JSONDecoder()
    
    init() {
        let packageInfo = PackageInfo()
        apiClient = MobileNebulaNewAPIClient("\(packageInfo.getName())/\(packageInfo.getVersion()) (iOS \(packageInfo.getSystemVersion()))")!
    }
    
    func enroll(code: String) throws -> IncomingSite {
        let res = try apiClient.enroll(code)
        return try decodeIncomingSite(jsonSite: res.site)
    }
    
    func tryUpdate(siteName: String, hostID: String, privateKey: String, counter: Int, trustedKeys: String) throws -> IncomingSite? {
        let res: MobileNebulaTryUpdateResult
        do {
            res = try apiClient.tryUpdate(
                siteName,
                hostID: hostID,
                privateKey: privateKey,
                counter: counter,
                trustedKeys: trustedKeys)
        } catch {
            // type information from Go is not available, use string matching instead
            if (error.localizedDescription == "invalid credentials") {
                throw APIClientError.invalidCredentials
            }
            
            throw error
        }
        
        if (res.fetchedUpdate) {
            return try decodeIncomingSite(jsonSite: res.site)
        }
        
        return nil
    }
    
    private func decodeIncomingSite(jsonSite: String) throws -> IncomingSite {
        do {
            return try json.decode(IncomingSite.self, from: jsonSite.data(using: .utf8)!)
        } catch {
            print("decodeIncomingSite: \(error)")
            throw error
        }
    }
}