using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
using BTCPayServer.Abstractions.Contracts;
using BTCPayServer.Client.Models;
using BTCPayServer.Configuration;
using BTCPayServer.Controllers;
using BTCPayServer.Data;
using BTCPayServer.Fido2;
using BTCPayServer.Fido2.Models;
using BTCPayServer.Logging;
using BTCPayServer.Models.AppViewModels;
using BTCPayServer.Payments;
using BTCPayServer.Payments.Lightning;
using BTCPayServer.Services;
using BTCPayServer.Services.Apps;
using BTCPayServer.Services.Stores;
using ExchangeSharp;
using Fido2NetLib.Objects;
using Microsoft.AspNetCore.Identity;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Options;
using NBXplorer;
using Newtonsoft.Json.Linq;
using PeterO.Cbor;

namespace BTCPayServer.Hosting
{
    public class MigrationStartupTask : IStartupTask
    {
        public Logs Logs { get; }

        private readonly ApplicationDbContextFactory _DBContextFactory;
        private readonly StoreRepository _StoreRepository;
        private readonly BTCPayNetworkProvider _NetworkProvider;
        private readonly SettingsRepository _Settings;
        private readonly AppService _appService;
        private readonly IEnumerable<IPayoutHandler> _payoutHandlers;
        private readonly BTCPayNetworkJsonSerializerSettings _btcPayNetworkJsonSerializerSettings;
        private readonly UserManager<ApplicationUser> _userManager;

        public IOptions<LightningNetworkOptions> LightningOptions { get; }

        public MigrationStartupTask(
            BTCPayNetworkProvider networkProvider,
            StoreRepository storeRepository,
            ApplicationDbContextFactory dbContextFactory,
            UserManager<ApplicationUser> userManager,
            IOptions<LightningNetworkOptions> lightningOptions,
            SettingsRepository settingsRepository,
            AppService appService,
            IEnumerable<IPayoutHandler> payoutHandlers,
            BTCPayNetworkJsonSerializerSettings btcPayNetworkJsonSerializerSettings,
            Logs logs)
        {
            Logs = logs;
            _DBContextFactory = dbContextFactory;
            _StoreRepository = storeRepository;
            _NetworkProvider = networkProvider;
            _Settings = settingsRepository;
            _appService = appService;
            _payoutHandlers = payoutHandlers;
            _btcPayNetworkJsonSerializerSettings = btcPayNetworkJsonSerializerSettings;
            _userManager = userManager;
            LightningOptions = lightningOptions;
        }
        public async Task ExecuteAsync(CancellationToken cancellationToken = default)
        {
            try
            {
                await Migrate(cancellationToken);
                var settings = (await _Settings.GetSettingAsync<MigrationSettings>()) ?? new MigrationSettings();
                if (!settings.PaymentMethodCriteria)
                {
                    await MigratePaymentMethodCriteria();
                    settings.PaymentMethodCriteria = true;
                    await _Settings.UpdateSetting(settings);
                }
                if (!settings.DeprecatedLightningConnectionStringCheck)
                {
                    await DeprecatedLightningConnectionStringCheck();
                    settings.DeprecatedLightningConnectionStringCheck = true;
                    await _Settings.UpdateSetting(settings);
                }
                if (!settings.UnreachableStoreCheck)
                {
                    await UnreachableStoreCheck();
                    settings.UnreachableStoreCheck = true;
                    await _Settings.UpdateSetting(settings);
                }
                if (!settings.ConvertMultiplierToSpread)
                {
                    await ConvertMultiplierToSpread();
                    settings.ConvertMultiplierToSpread = true;
                    await _Settings.UpdateSetting(settings);
                }
                if (!settings.ConvertNetworkFeeProperty)
                {
                    await ConvertNetworkFeeProperty();
                    settings.ConvertNetworkFeeProperty = true;
                    await _Settings.UpdateSetting(settings);
                }
                if (!settings.ConvertCrowdfundOldSettings)
                {
                    await ConvertCrowdfundOldSettings();
                    settings.ConvertCrowdfundOldSettings = true;
                    await _Settings.UpdateSetting(settings);
                }
                if (!settings.ConvertWalletKeyPathRoots)
                {
                    await ConvertConvertWalletKeyPathRoots();
                    settings.ConvertWalletKeyPathRoots = true;
                    await _Settings.UpdateSetting(settings);
                }
                if (!settings.CheckedFirstRun)
                {
                    var themeSettings = await _Settings.GetSettingAsync<ThemeSettings>() ?? new ThemeSettings();
                    var admin = await _userManager.GetUsersInRoleAsync(Roles.ServerAdmin);
                    themeSettings.FirstRun = admin.Count == 0;
                    await _Settings.UpdateSetting(themeSettings);
                    settings.CheckedFirstRun = true;
                    await _Settings.UpdateSetting(settings);
                }

                if (!settings.TransitionToStoreBlobAdditionalData)
                {
                    await TransitionToStoreBlobAdditionalData();
                    settings.TransitionToStoreBlobAdditionalData = true;
                    await _Settings.UpdateSetting(settings);
                }

                if (!settings.TransitionInternalNodeConnectionString)
                {
                    await TransitionInternalNodeConnectionString();
                    settings.TransitionInternalNodeConnectionString = true;
                    await _Settings.UpdateSetting(settings);
                }

                if (!settings.MigrateU2FToFIDO2)
                {
                    await MigrateU2FToFIDO2();
                    settings.MigrateU2FToFIDO2 = true;
                    await _Settings.UpdateSetting(settings);
                }
                if (!settings.MigrateHotwalletProperty)
                {
                    await MigrateHotwalletProperty();
                    settings.MigrateHotwalletProperty = true;
                    await _Settings.UpdateSetting(settings);
                }
                if (!settings.MigrateAppCustomOption)
                {
                    await MigrateAppCustomOption();
                    settings.MigrateAppCustomOption = true;
                    await _Settings.UpdateSetting(settings);
                }
                if (!settings.MigratePayoutDestinationId)
                {
                    await MigratePayoutDestinationId();
                    settings.MigratePayoutDestinationId = true;
                    await _Settings.UpdateSetting(settings);
                }
                if (!settings.AddInitialUserBlob)
                {
                    await AddInitialUserBlob();
                    settings.AddInitialUserBlob = true;
                    await _Settings.UpdateSetting(settings);
                }
                if (!settings.LighingAddressSettingRename)
                {
                    await MigrateLighingAddressSettingRename();
                    settings.LighingAddressSettingRename = true;
                    await _Settings.UpdateSetting(settings);
                }
            }
            catch (Exception ex)
            {
                Logs.PayServer.LogError(ex, "Error on the MigrationStartupTask");
                throw;
            }
        }

        private async Task MigrateLighingAddressSettingRename()
        {
           var old = await _Settings.GetSettingAsync<UILNURLController.LightningAddressSettings>("BTCPayServer.LNURLController+LightningAddressSettings");
           if (old is not null)
           {
              await _Settings.UpdateSetting(old, nameof(UILNURLController.LightningAddressSettings));
           }
        }

        private async Task AddInitialUserBlob()
        {
            await using var ctx = _DBContextFactory.CreateContext();
            foreach (var user in await ctx.Users.AsQueryable().ToArrayAsync())
            {
                user.SetBlob(new UserBlob() { ShowInvoiceStatusChangeHint = true });
            }
            await ctx.SaveChangesAsync();
        }

        private async Task MigratePayoutDestinationId()
        {
            await using var ctx = _DBContextFactory.CreateContext();
            foreach (var payoutData in await ctx.Payouts.AsQueryable().ToArrayAsync())
            {
                var pmi = payoutData.GetPaymentMethodId();
                if (pmi is null)
                {
                    continue;
                }
                var handler = _payoutHandlers
                    .FindPayoutHandler(pmi);
                if (handler is null)
                {
                    continue;
                }
                var claim = await handler?.ParseClaimDestination(pmi, payoutData.GetBlob(_btcPayNetworkJsonSerializerSettings).Destination);
                payoutData.Destination = claim.destination?.Id;
            }
            await ctx.SaveChangesAsync();
        }

        private async Task MigrateAppCustomOption()
        {
            await using var ctx = _DBContextFactory.CreateContext();
            foreach (var app in await ctx.Apps.Include(data => data.StoreData).AsQueryable().ToArrayAsync())
            {
                ViewPointOfSaleViewModel.Item[] items;
                string newTemplate;
                switch (app.AppType)
                {
                    case nameof(AppType.Crowdfund):
                        var settings1 = app.GetSettings<CrowdfundSettings>();
                        if (string.IsNullOrEmpty(settings1.TargetCurrency))
                        {
                            settings1.TargetCurrency = app.StoreData.GetStoreBlob().DefaultCurrency;
                            app.SetSettings(settings1);
                        }
                        items = _appService.Parse(settings1.PerksTemplate, settings1.TargetCurrency);
                        newTemplate = _appService.SerializeTemplate(items);
                        if (settings1.PerksTemplate != newTemplate)
                        {
                            settings1.PerksTemplate = newTemplate;
                            app.SetSettings(settings1);
                        };
                        break;

                    case nameof(AppType.PointOfSale):

                        var settings2 = app.GetSettings<UIAppsController.PointOfSaleSettings>();
                        if (string.IsNullOrEmpty(settings2.Currency))
                        {
                            settings2.Currency = app.StoreData.GetStoreBlob().DefaultCurrency;
                            app.SetSettings(settings2);
                        }
                        items = _appService.Parse(settings2.Template, settings2.Currency);
                        newTemplate = _appService.SerializeTemplate(items);
                        if (settings2.Template != newTemplate)
                        {
                            settings2.Template = newTemplate;
                            app.SetSettings(settings2);
                        };
                        break;
                }
            }
            await ctx.SaveChangesAsync();
        }

        private async Task MigrateHotwalletProperty()
        {
            await using var ctx = _DBContextFactory.CreateContext();
            foreach (var store in await ctx.Stores.AsQueryable().ToArrayAsync())
            {
                foreach (var paymentMethod in store.GetSupportedPaymentMethods(_NetworkProvider).OfType<DerivationSchemeSettings>())
                {
                    paymentMethod.IsHotWallet = paymentMethod.Source == "NBXplorer";
                    if (paymentMethod.IsHotWallet)
                    {
                        paymentMethod.Source = "NBXplorerGenerated";
                        store.SetSupportedPaymentMethod(paymentMethod);
                    }
                }
            }
            await ctx.SaveChangesAsync();
        }

        private async Task MigrateU2FToFIDO2()
        {
            await using var ctx = _DBContextFactory.CreateContext();
            var u2fDevices = await ctx.U2FDevices.ToListAsync();
            foreach (U2FDevice u2FDevice in u2fDevices)
            {
                var fido2 = new Fido2Credential()
                {
                    ApplicationUserId = u2FDevice.ApplicationUserId,
                    Name = u2FDevice.Name,
                    Type = Fido2Credential.CredentialType.FIDO2
                };
                fido2.SetBlob(new Fido2CredentialBlob()
                {
                    SignatureCounter = (uint)u2FDevice.Counter,
                    PublicKey = CreatePublicKeyFromU2fRegistrationData(u2FDevice.PublicKey).EncodeToBytes(),
                    UserHandle = u2FDevice.KeyHandle,
                    Descriptor = new PublicKeyCredentialDescriptor(u2FDevice.KeyHandle),
                    CredType = "u2f"
                });

                await ctx.AddAsync(fido2);

                ctx.Remove(u2FDevice);
            }
            await ctx.SaveChangesAsync();
        }
        //from https://github.com/abergs/fido2-net-lib/blob/0fa7bb4b4a1f33f46c5f7ca4ee489b47680d579b/Test/ExistingU2fRegistrationDataTests.cs#L70
        private static CBORObject CreatePublicKeyFromU2fRegistrationData(byte[] publicKeyData)
        {
            if (publicKeyData.Length != 65)
            {
                throw new ArgumentException("u2f public key must be 65 bytes", nameof(publicKeyData));
            }
            var x = new byte[32];
            var y = new byte[32];
            Buffer.BlockCopy(publicKeyData, 1, x, 0, 32);
            Buffer.BlockCopy(publicKeyData, 33, y, 0, 32);


            var coseKey = CBORObject.NewMap();

            coseKey.Add(COSE.KeyCommonParameter.KeyType, COSE.KeyType.EC2);
            coseKey.Add(COSE.KeyCommonParameter.Alg, -7);

            coseKey.Add(COSE.KeyTypeParameter.Crv, COSE.EllipticCurve.P256);

            coseKey.Add(COSE.KeyTypeParameter.X, x);
            coseKey.Add(COSE.KeyTypeParameter.Y, y);

            return coseKey;
        }

        private async Task TransitionInternalNodeConnectionString()
        {
            var nodes = LightningOptions.Value.InternalLightningByCryptoCode.Values.Select(c => c.ToString()).ToHashSet();
            await using var ctx = _DBContextFactory.CreateContext();
            foreach (var store in await ctx.Stores.AsQueryable().ToArrayAsync())
            {
#pragma warning disable CS0618 // Type or member is obsolete
                if (!string.IsNullOrEmpty(store.DerivationStrategy))
                {
                    var noLabel = store.DerivationStrategy.Split('-')[0];
                    JObject jObject = new JObject();
                    jObject.Add("BTC", new JObject()
                    {
                        new JProperty("signingKey", noLabel),
                        new JProperty("accountDerivation", store.DerivationStrategy),
                        new JProperty("accountOriginal", store.DerivationStrategy),
                        new JProperty("accountKeySettings", new JArray()
                        {
                            new JObject()
                            {
                                new JProperty("accountKey", noLabel)
                            }
                        })
                    });
                    store.DerivationStrategies = jObject.ToString();
                    store.DerivationStrategy = null;
                }
                if (string.IsNullOrEmpty(store.DerivationStrategies))
                    continue;

                var strats = JObject.Parse(store.DerivationStrategies);
                bool updated = false;
                foreach (var prop in strats.Properties().Where(p => p.Name.EndsWith("LightningLike", StringComparison.OrdinalIgnoreCase)))
                {
                    var method = ((JObject)prop.Value);
                    var lightningCharge = method.Property("LightningChargeUrl", StringComparison.OrdinalIgnoreCase);
                    var ln = method.Property("LightningConnectionString", StringComparison.OrdinalIgnoreCase);
                    if (lightningCharge != null)
                    {
                        var chargeUrl = lightningCharge.Value.Value<string>();
                        var usr = method.Property("Username", StringComparison.OrdinalIgnoreCase)?.Value.Value<string>();
                        var pass = method.Property("Password", StringComparison.OrdinalIgnoreCase)?.Value.Value<string>();
                        updated = true;
                        if (chargeUrl != null)
                        {
                            var fullUri = new UriBuilder(chargeUrl)
                            {
                                UserName = usr,
                                Password = pass
                            }.Uri.AbsoluteUri;
                            var newStr = $"type=charge;server={fullUri};allowinsecure=true";
                            if (ln is null)
                            {
                                ln = new JProperty("LightningConnectionString", newStr);
                                method.Add(ln);
                            }
                            else
                            {
                                ln.Value = newStr;
                            }
                        }
                        foreach (var p in new[] { "Username", "Password", "LightningChargeUrl" })
                            method.Property(p, StringComparison.OrdinalIgnoreCase)?.Remove();
                    }

                    var paymentId = method.Property("PaymentId", StringComparison.OrdinalIgnoreCase);
                    if (paymentId != null)
                    {
                        paymentId.Remove();
                        updated = true;
                    }

                    if (ln is null)
                        continue;
                    if (nodes.Contains(ln.Value.Value<string>()))
                    {
                        updated = true;
                        ln.Value = null;
                        if (!(method.Property("InternalNodeRef", StringComparison.OrdinalIgnoreCase) is JProperty internalNode))
                        {
                            internalNode = new JProperty("InternalNodeRef", null);
                            method.Add(internalNode);
                        }
                        internalNode.Value = new JValue(LightningSupportedPaymentMethod.InternalNode);
                    }
                }

                if (updated)
                    store.DerivationStrategies = strats.ToString();
#pragma warning restore CS0618 // Type or member is obsolete
            }
            await ctx.SaveChangesAsync();
        }

        private async Task TransitionToStoreBlobAdditionalData()
        {
            await using var ctx = _DBContextFactory.CreateContext();
            foreach (var store in await ctx.Stores.AsQueryable().ToArrayAsync())
            {
                var blob = store.GetStoreBlob();
                blob.AdditionalData.Remove("walletKeyPathRoots");
                blob.AdditionalData.Remove("onChainMinValue");
                blob.AdditionalData.Remove("lightningMaxValue");
                blob.AdditionalData.Remove("networkFeeDisabled");
                blob.AdditionalData.Remove("rateRules");
                store.SetStoreBlob(blob);
            }

            await ctx.SaveChangesAsync();
        }

        private async Task Migrate(CancellationToken cancellationToken)
        {
            using (CancellationTokenSource timeout = new CancellationTokenSource(10_000))
            using (CancellationTokenSource cts = CancellationTokenSource.CreateLinkedTokenSource(timeout.Token, cancellationToken))
            {
retry:
                try
                {
                    await _DBContextFactory.CreateContext().Database.MigrateAsync();
                }
                // Starting up
                catch when (!cts.Token.IsCancellationRequested)
                {
                    try
                    {
                        await Task.Delay(1000, cts.Token);
                    }
                    catch { }
                    goto retry;
                }
            }
        }

        private async Task ConvertConvertWalletKeyPathRoots()
        {
            bool save = false;
            using var ctx = _DBContextFactory.CreateContext();
            foreach (var store in await ctx.Stores.AsQueryable().ToArrayAsync())
            {
#pragma warning disable CS0618 // Type or member is obsolete
                var blob = store.GetStoreBlob();

                if (blob.AdditionalData.TryGetValue("walletKeyPathRoots", out var walletKeyPathRootsJToken))
                {
                    var walletKeyPathRoots = walletKeyPathRootsJToken.ToObject<Dictionary<string, string>>();

                    if (!(walletKeyPathRoots?.Any() is true))
                        continue;
                    foreach (var scheme in store.GetSupportedPaymentMethods(_NetworkProvider)
                        .OfType<DerivationSchemeSettings>())
                    {
                        if (walletKeyPathRoots.TryGetValue(scheme.PaymentId.ToString().ToLowerInvariant(),
                            out var root))
                        {
                            scheme.AccountKeyPath = new NBitcoin.KeyPath(root);
                            store.SetSupportedPaymentMethod(scheme);
                            save = true;
                        }
                    }

                    blob.AdditionalData.Remove("walletKeyPathRoots");
                    store.SetStoreBlob(blob);
                }
#pragma warning restore CS0618 // Type or member is obsolete
            }
            if (save)
                await ctx.SaveChangesAsync();
        }

        private async Task ConvertCrowdfundOldSettings()
        {
            using var ctx = _DBContextFactory.CreateContext();
            foreach (var app in await ctx.Apps.Where(a => a.AppType == "Crowdfund").ToArrayAsync())
            {
                var settings = app.GetSettings<Services.Apps.CrowdfundSettings>();
#pragma warning disable CS0618 // Type or member is obsolete
                if (settings.UseAllStoreInvoices)
#pragma warning restore CS0618 // Type or member is obsolete
                {
                    app.TagAllInvoices = true;
                }
            }
            await ctx.SaveChangesAsync();
        }

        private async Task MigratePaymentMethodCriteria()
        {
            using var ctx = _DBContextFactory.CreateContext();
            foreach (var store in await ctx.Stores.AsQueryable().ToArrayAsync())
            {
                var blob = store.GetStoreBlob();

                CurrencyValue onChainMinValue = null;
                CurrencyValue lightningMaxValue = null;
                if (blob.AdditionalData.TryGetValue("onChainMinValue", out var onChainMinValueJToken))
                {
                    CurrencyValue.TryParse(onChainMinValueJToken.Value<string>(), out onChainMinValue);
                    blob.AdditionalData.Remove("onChainMinValue");
                }
                if (blob.AdditionalData.TryGetValue("lightningMaxValue", out var lightningMaxValueJToken))
                {
                    CurrencyValue.TryParse(lightningMaxValueJToken.Value<string>(), out lightningMaxValue);
                    blob.AdditionalData.Remove("lightningMaxValue");
                }
                blob.PaymentMethodCriteria = store.GetEnabledPaymentIds(_NetworkProvider).Select(paymentMethodId =>
               {
                   var matchedFromBlob =
                       blob.PaymentMethodCriteria?.SingleOrDefault(criteria => criteria.PaymentMethod == paymentMethodId && criteria.Value != null);
                   return matchedFromBlob switch
                   {
                       null when paymentMethodId.PaymentType == LightningPaymentType.Instance &&
                                 lightningMaxValue != null => new PaymentMethodCriteria()
                                 {
                                     Above = false,
                                     PaymentMethod = paymentMethodId,
                                     Value = lightningMaxValue
                                 },
                       null when paymentMethodId.PaymentType == BitcoinPaymentType.Instance &&
                                 onChainMinValue != null => new PaymentMethodCriteria()
                                 {
                                     Above = true,
                                     PaymentMethod = paymentMethodId,
                                     Value = onChainMinValue
                                 },
                       _ => new PaymentMethodCriteria()
                       {
                           PaymentMethod = paymentMethodId,
                           Above = matchedFromBlob?.Above ?? true,
                           Value = matchedFromBlob?.Value
                       }
                   };
               }).ToList();

                store.SetStoreBlob(blob);
            }

            await ctx.SaveChangesAsync();
        }

        private async Task ConvertNetworkFeeProperty()
        {
            using var ctx = _DBContextFactory.CreateContext();
            foreach (var store in await ctx.Stores.AsQueryable().ToArrayAsync())
            {
                var blob = store.GetStoreBlob();
                if (blob.AdditionalData.TryGetValue("networkFeeDisabled", out var networkFeeModeJToken))
                {
                    var networkFeeMode = networkFeeModeJToken.ToObject<bool?>();
                    if (networkFeeMode != null)
                    {
                        blob.NetworkFeeMode = networkFeeMode.Value ? NetworkFeeMode.Never : NetworkFeeMode.Always;
                    }

                    blob.AdditionalData.Remove("networkFeeDisabled");
                    store.SetStoreBlob(blob);
                }
            }
            await ctx.SaveChangesAsync();
        }

        private async Task ConvertMultiplierToSpread()
        {
            using var ctx = _DBContextFactory.CreateContext();
            foreach (var store in await ctx.Stores.AsQueryable().ToArrayAsync())
            {
                var blob = store.GetStoreBlob();
                decimal multiplier = 1.0m;
                if (blob.AdditionalData.TryGetValue("rateRules", out var rateRulesJToken))
                {
                    var rateRules = new Serializer(null).ToObject<List<RateRule_Obsolete>>(rateRulesJToken.ToString());
                    if (rateRules != null && rateRules.Count != 0)
                    {
                        foreach (var rule in rateRules)
                        {
                            multiplier = rule.Apply(null, multiplier);
                        }
                    }

                    blob.AdditionalData.Remove("rateRules");
                    blob.Spread = Math.Min(1.0m, Math.Max(0m, -(multiplier - 1.0m)));
                    store.SetStoreBlob(blob);
                }
            }
            await ctx.SaveChangesAsync();
        }

        public class RateRule_Obsolete
        {
            public RateRule_Obsolete()
            {
                RuleName = "Multiplier";
            }
            public string RuleName { get; set; }

            public double Multiplier { get; set; }

            public decimal Apply(BTCPayNetworkBase network, decimal rate)
            {
                return rate * (decimal)Multiplier;
            }
        }

        private Task UnreachableStoreCheck()
        {
            return _StoreRepository.CleanUnreachableStores();
        }

        private async Task DeprecatedLightningConnectionStringCheck()
        {
            using var ctx = _DBContextFactory.CreateContext();
            foreach (var store in await ctx.Stores.AsQueryable().ToArrayAsync())
            {
                foreach (var method in store.GetSupportedPaymentMethods(_NetworkProvider).OfType<Payments.Lightning.LightningSupportedPaymentMethod>())
                {
                    var lightning = method.GetExternalLightningUrl();
                    if (lightning?.IsLegacy is true)
                    {
                        method.SetLightningUrl(lightning);
                        store.SetSupportedPaymentMethod(method);
                    }
                }
            }
            await ctx.SaveChangesAsync();
        }
    }
}