// Copyright (c) .NET Foundation. All rights reserved.
// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.

using System;
using System.IO;
using System.Runtime.InteropServices;
using Microsoft.AspNetCore.DataProtection;
using Microsoft.AspNetCore.DataProtection.KeyManagement;
using Microsoft.Extensions.DependencyInjection;

namespace KeyManagementSample
{
    public class Program
    {
        public static void Main(string[] args)
        {
            var keysFolder = Path.Combine(Directory.GetCurrentDirectory(), "temp-keys");
            var serviceCollection = new ServiceCollection();
            var builder = serviceCollection
                .AddDataProtection()
                // point at a specific folder and use DPAPI to encrypt keys
                .PersistKeysToFileSystem(new DirectoryInfo(keysFolder));
            if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
            {
                builder.ProtectKeysWithDpapi();
            }

            using (var services = serviceCollection.BuildServiceProvider())
            {
                // perform a protect operation to force the system to put at least
                // one key in the key ring
                services.GetDataProtector("Sample.KeyManager.v1").Protect("payload");
                Console.WriteLine("Performed a protect operation.");

                // get a reference to the key manager
                var keyManager = services.GetService<IKeyManager>();

                // list all keys in the key ring
                var allKeys = keyManager.GetAllKeys();
                Console.WriteLine($"The key ring contains {allKeys.Count} key(s).");
                foreach (var key in allKeys)
                {
                    Console.WriteLine($"Key {key.KeyId:B}: Created = {key.CreationDate:u}, IsRevoked = {key.IsRevoked}");
                }

                // revoke all keys in the key ring
                keyManager.RevokeAllKeys(DateTimeOffset.Now, reason: "Revocation reason here.");
                Console.WriteLine("Revoked all existing keys.");

                // add a new key to the key ring with immediate activation and a 1-month expiration
                keyManager.CreateNewKey(
                    activationDate: DateTimeOffset.Now,
                    expirationDate: DateTimeOffset.Now.AddMonths(1));
                Console.WriteLine("Added a new key.");

                // list all keys in the key ring
                allKeys = keyManager.GetAllKeys();
                Console.WriteLine($"The key ring contains {allKeys.Count} key(s).");
                foreach (var key in allKeys)
                {
                    Console.WriteLine($"Key {key.KeyId:B}: Created = {key.CreationDate:u}, IsRevoked = {key.IsRevoked}");
                }
            }
        }
    }
}