using System;
using System.Collections.Generic;
using System.Linq;
using System.Net.Http;
using System.Text.Json;
using System.Threading;
using System.Threading.Tasks;
using Microsoft.Extensions.DependencyInjection;
using PolyTrader.Core.Persistence;
using PolyTrader.Core.Persistence.Ef;
using PolyTrader.Core.Platforms;
using PolyTrader.Core.Platforms.PolymarketGlobal;
using PolyTrader.Core.Trading;
using PolyTrader.Tests.Fakes;
using PolyTrader.Tests.TestSupport;
using PolyTraderSharp.Models;
using PolyTraderSharp.Services;
using Xunit;

namespace PolyTrader.Tests
{
    /// <summary>
    /// #623 Plattform-Fundament: Kennungen, Registry, und dass der Global-Adapter den bestehenden CLOB-Client
    /// genau so aufruft, wie die Module es vor #623 selbst getan haben.
    /// </summary>
    public class PlatformTests
    {
        // ── PlatformId ─────────────────────────────────────────────────────────

        [Theory]
        [InlineData(null)]
        [InlineData("")]
        [InlineData("   ")]
        public void Parse_of_missing_value_is_polymarket_global(string? stored)
        {
            Assert.Equal(PlatformId.PolymarketGlobal, PlatformId.Parse(stored));
        }

        [Fact]
        public void Parse_normalizes_case_and_whitespace()
        {
            Assert.Equal(PlatformId.PolymarketUs, PlatformId.Parse("  Polymarket-US "));
        }

        [Fact]
        public void Stored_values_are_stable()
        {
            // Diese Werte stehen in der Datenbank. Ändert sich einer, verlieren Bestandskonten ihre Plattform.
            Assert.Equal("polymarket-global", PlatformId.PolymarketGlobal.Value);
            Assert.Equal("polymarket-us", PlatformId.PolymarketUs.Value);
            Assert.Equal("kalshi", PlatformId.Kalshi.Value);
        }

        [Fact]
        public void New_accounts_and_markets_default_to_polymarket_global()
        {
            Assert.Equal(PlatformId.PolymarketGlobalValue, new AccountState().Platform);
            Assert.Equal(PlatformId.PolymarketGlobalValue, new MarketData().Platform);
        }

        // ── InstrumentRef ─────────────────────────────────────────────────────

        [Fact]
        public void Instruments_are_equal_by_platform_and_key_only()
        {
            var a = InstrumentRef.PolymarketGlobal("123", "0xcond", "Yes");
            var b = InstrumentRef.PolymarketGlobal("123");
            Assert.Equal(a, b);
            Assert.Equal(a.GetHashCode(), b.GetHashCode());
        }

        [Fact]
        public void Same_key_on_different_platforms_is_a_different_instrument()
        {
            Assert.NotEqual(
                new InstrumentRef(PlatformId.PolymarketGlobal, "x"),
                new InstrumentRef(PlatformId.PolymarketUs, "x"));
        }

        [Fact]
        public void Empty_instrument_key_is_rejected()
        {
            Assert.Throws<ArgumentException>(() => new InstrumentRef(PlatformId.PolymarketGlobal, " "));
        }

        // ── Registry ──────────────────────────────────────────────────────────

        [Fact]
        public void Registry_resolves_adapter_for_account_platform()
        {
            var global = NewGlobalAdapter(new FakeClobClient(), new StubMarketRepository());
            var registry = new PlatformRegistry(new[] { global });

            Assert.Same(global, registry.ForAccount(new AccountState()));
            Assert.Same(global, registry.ForAccount(new AccountState { Platform = "" }));
            Assert.Equal(new[] { PlatformId.PolymarketGlobal }, registry.Available);
        }

        [Fact]
        public void Registry_names_missing_platform_instead_of_returning_null()
        {
            var registry = new PlatformRegistry(new[] { NewGlobalAdapter(new FakeClobClient(), new StubMarketRepository()) });

            var ex = Assert.Throws<InvalidOperationException>(() => registry.Get(PlatformId.PolymarketUs));
            Assert.Contains("Polymarket US", ex.Message);
            Assert.False(registry.TryGet(PlatformId.Kalshi, out _));
        }

        [Fact]
        public void Registry_refuses_two_adapters_for_one_platform()
        {
            var a = NewGlobalAdapter(new FakeClobClient(), new StubMarketRepository());
            var b = NewGlobalAdapter(new FakeClobClient(), new StubMarketRepository());
            Assert.Throws<InvalidOperationException>(() => new PlatformRegistry(new[] { a, b }));
        }

        [Fact]
        public void AddPlatforms_wires_global_adapter_from_the_app_singletons()
        {
            // Wie Program.cs: API-Dienst, CLOB-Client und Persistenz sind registriert, CopyTrading (und damit
            // dessen IClobClient-Registrierung) bewusst NICHT – der Adapter muss trotzdem auflösbar sein.
            var logger = new TerminalLogger();
            var services = new ServiceCollection();
            services.AddSingleton(new PolymarketApiService(logger, new HttpClient()));
            services.AddSingleton(new PolymarketClobClient(logger, new HttpClient()));
            services.AddSingleton<IMarketRepository>(new StubMarketRepository());

            services.AddPlatforms();
            using var sp = services.BuildServiceProvider();
            var registry = sp.GetRequiredService<IPlatformRegistry>();

            var adapter = registry.ForAccount(new AccountState());
            Assert.IsType<PolymarketGlobalAdapter>(adapter);
            Assert.IsType<GlobalOrderGateway>(adapter.Orders);
            Assert.True(adapter.Capabilities.PublicTraderActivity);
            Assert.False(adapter.Capabilities.PostOnlyOrders);
        }

        // ── Global-Gateway: derselbe CLOB-Aufruf wie vorher ───────────────────

        [Fact]
        public async Task Buy_by_notional_passes_amount_price_negrisk_and_market_fee_through()
        {
            var clob = new FakeClobClient();
            var markets = new StubMarketRepository(new MarketData
            {
                Id = "m1", ClobTokenIds = "[\"tok-yes\",\"tok-no\"]", NegRisk = true, TakerFeeBps = 180, Category = "Sports"
            });
            var gateway = new GlobalOrderGateway(clob, markets);

            var result = await gateway.PlaceAsync(new AccountState(), new OrderRequest
            {
                Instrument = InstrumentRef.PolymarketGlobal("tok-yes"),
                Side = OrderSide.Buy,
                LimitPrice = 0.42m,
                NotionalUsd = 25m,
                TimeInForce = TimeInForce.FillOrKill
            });

            Assert.True(result.IsAccepted);
            var placed = Assert.Single(clob.Placed);
            Assert.Equal(new FakeClobClient.PlacedOrder("tok-yes", "BUY", 25m, 0.42m, "FOK", IsNegRisk: true, FeeBps: 180), placed);
        }

        [Fact]
        public async Task Sell_by_quantity_converts_to_amount_like_the_sell_ladder()
        {
            // Die SELL-Leiter übergibt pos.Size * Preis als Betrag – das Gateway muss dasselbe senden.
            var clob = new FakeClobClient();
            var gateway = new GlobalOrderGateway(clob, new StubMarketRepository());

            await gateway.PlaceAsync(new AccountState(), new OrderRequest
            {
                Instrument = InstrumentRef.PolymarketGlobal("tok"),
                Side = OrderSide.Sell,
                LimitPrice = 0.8m,
                Quantity = 50m,
                TimeInForce = TimeInForce.GoodTillCancel
            });

            var placed = Assert.Single(clob.Placed);
            Assert.Equal("SELL", placed.Side);
            Assert.Equal(40m, placed.Usdc);
            Assert.Equal("GTC", placed.OrderType);
        }

        [Fact]
        public async Task Unknown_market_uses_conservative_fee_fallback_and_no_negrisk()
        {
            var clob = new FakeClobClient();
            var gateway = new GlobalOrderGateway(clob, new StubMarketRepository());

            await gateway.PlaceAsync(new AccountState(), Buy("tok", 0.5m, 10m));

            var placed = Assert.Single(clob.Placed);
            Assert.False(placed.IsNegRisk);
            Assert.Equal(FeeModel.FallbackBps(null), placed.FeeBps);
        }

        public static IEnumerable<object[]> InvalidRequests()
        {
            var ok = Buy("tok", 0.5m, 10m);
            yield return new object[] { ok with { Instrument = new InstrumentRef(PlatformId.PolymarketUs, "slug:YES") }, "Polymarket US" };
            yield return new object[] { ok with { PostOnly = true }, "Post-only" };
            yield return new object[] { ok with { TimeInForce = TimeInForce.ImmediateOrCancel }, "Gültigkeit" };
            yield return new object[] { ok with { TimeInForce = TimeInForce.GoodTillDate }, "Gültigkeit" };
            yield return new object[] { ok with { LimitPrice = 1m }, "Limitpreis" };
            yield return new object[] { ok with { LimitPrice = 0m }, "Limitpreis" };
            yield return new object[] { ok with { Quantity = 5m }, "Mengenangabe" };
            yield return new object[] { ok with { NotionalUsd = null }, "Mengenangabe" };
            yield return new object[] { ok with { NotionalUsd = 0m }, "größer als 0" };
        }

        [Theory]
        [MemberData(nameof(InvalidRequests))]
        public async Task Invalid_request_never_reaches_the_clob(OrderRequest request, string expectedHint)
        {
            var clob = new FakeClobClient();
            var gateway = new GlobalOrderGateway(clob, new StubMarketRepository());

            var result = await gateway.PlaceAsync(new AccountState(), request);

            Assert.Equal(OrderOutcome.Invalid, result.Outcome);
            Assert.Contains(expectedHint, result.Message);
            Assert.Empty(clob.Placed);
        }

        [Fact]
        public async Task Account_of_another_platform_never_reaches_the_clob()
        {
            var clob = new FakeClobClient();
            var gateway = new GlobalOrderGateway(clob, new StubMarketRepository());

            var result = await gateway.PlaceAsync(new AccountState { Platform = PlatformId.PolymarketUsValue }, Buy("tok", 0.5m, 10m));

            Assert.Equal(OrderOutcome.Invalid, result.Outcome);
            Assert.Empty(clob.Placed);
        }

        [Theory]
        [InlineData("OK", OrderOutcome.Accepted)]
        [InlineData("SKIPPED_LIQUIDITY", OrderOutcome.NotFilled)]
        [InlineData("ERROR", OrderOutcome.Rejected)]
        [InlineData("Error: Missing API or Private Keys", OrderOutcome.Rejected)]
        [InlineData("", OrderOutcome.Rejected)]
        public async Task Clob_response_is_mapped(string response, OrderOutcome expected)
        {
            var clob = new FakeClobClient { PlaceResult = response };
            var gateway = new GlobalOrderGateway(clob, new StubMarketRepository());

            var result = await gateway.PlaceAsync(new AccountState(), Buy("tok", 0.5m, 10m));

            Assert.Equal(expected, result.Outcome);
        }

        [Fact]
        public async Task Open_orders_and_cancel_go_to_the_clob()
        {
            var clob = new FakeClobClient();
            clob.OpenOrdersByAsset["tok"] = new() { ("o1", "SELL", 0.7m) };
            clob.AllOpenOrders.Add(("o2", "BUY", 0.3m));
            var gateway = new GlobalOrderGateway(clob, new StubMarketRepository());
            var instrument = InstrumentRef.PolymarketGlobal("tok");

            var forToken = await gateway.GetOpenOrdersAsync(new AccountState(), instrument);
            var all = await gateway.GetOpenOrdersAsync(new AccountState());
            bool canceled = await gateway.CancelAsync(new AccountState(), "o1");

            Assert.Equal(new OpenOrder("o1", OrderSide.Sell, 0.7m, instrument), Assert.Single(forToken));
            Assert.Equal(new OpenOrder("o2", OrderSide.Buy, 0.3m), Assert.Single(all));
            Assert.True(canceled);
            Assert.Equal(new[] { "o1" }, clob.CanceledOrderIds);
        }

        // ── Markt- und Positionsdaten ─────────────────────────────────────────

        [Fact]
        public void Stored_market_maps_outcomes_to_instruments_in_order()
        {
            var market = GlobalMarketCatalog.ToPlatformMarket(new MarketData
            {
                Id = "555", ConditionId = "0xcond", Slug = "ev", Question = "Q?", Category = "Politics",
                ClobTokenIds = "[\"t-yes\", \"t-no\"]", Outcomes = "[\"Yes\", \"No\"]",
                EndDate = new DateTime(2026, 11, 3, 0, 0, 0, DateTimeKind.Utc), Active = true
            });

            Assert.Equal(PlatformId.PolymarketGlobal, market.Platform);
            Assert.Equal("0xcond", market.MarketKey);
            Assert.Equal(new[] { "Yes", "No" }, market.Outcomes.Select(o => o.Name));
            Assert.Equal("t-no", market.Outcomes[1].Instrument.Key);
            Assert.Equal("0xcond", market.Outcomes[1].Instrument.MarketKey);
        }

        [Theory]
        [InlineData("")]
        [InlineData("not json")]
        [InlineData("{\"a\":1}")]
        public void Market_without_readable_token_ids_has_no_outcomes(string clobTokenIds)
        {
            var market = GlobalMarketCatalog.ToPlatformMarket(new MarketData { Id = "1", ClobTokenIds = clobTokenIds });
            Assert.Empty(market.Outcomes);
            Assert.Equal("1", market.MarketKey);   // ohne ConditionId die Gamma-ID
        }

        [Fact]
        public void Data_api_position_is_mapped_with_numbers_as_text_or_number()
        {
            using var doc = JsonDocument.Parse("""
                {"asset":"tok","conditionId":"0xc","outcome":"Yes","size":"12.5","avgPrice":0.4,
                 "curPrice":"0.55","initialValue":5,"currentValue":"6.875","slug":"s","title":"T",
                 "endDate":"2026-12-31T00:00:00Z"}
                """);

            var pos = GlobalPortfolioSource.ToPosition(doc.RootElement)!;

            Assert.Equal(InstrumentRef.PolymarketGlobal("tok"), pos.Instrument);
            Assert.Equal(12.5m, pos.Size);
            Assert.Equal(0.4m, pos.AveragePrice);
            Assert.Equal(0.55m, pos.CurrentPrice);
            Assert.Equal(5m, pos.CostUsd);
            Assert.Equal(6.875m, pos.CurrentValueUsd);
            Assert.Equal(new DateTime(2026, 12, 31, 0, 0, 0, DateTimeKind.Utc), pos.EndDateUtc);
        }

        [Fact]
        public void Data_api_entry_without_asset_is_skipped()
        {
            using var doc = JsonDocument.Parse("{\"size\":\"3\"}");
            Assert.Null(GlobalPortfolioSource.ToPosition(doc.RootElement));
        }

        // ── Gebühren ──────────────────────────────────────────────────────────

        [Fact]
        public void Global_taker_fee_equals_existing_fee_model()
        {
            var fees = new GlobalFeeModel();
            var ctx = new FeeContext { Category = "Crypto" };

            decimal fee = fees.EstimateFee(0.5m, 100m, LiquidityRole.Taker, ctx);

            Assert.Equal(FeeModel.FeeUsd(50m, FeeModel.CryptoBps), fee);
            Assert.Equal(FeeModel.FeeUsd(50m, 75), fees.EstimateFee(0.5m, 100m, LiquidityRole.Taker, new FeeContext { MarketFeeBps = 75 }));
        }

        [Fact]
        public void Global_maker_pays_nothing()
        {
            Assert.Equal(0m, new GlobalFeeModel().EstimateFee(0.5m, 100m, LiquidityRole.Maker, FeeContext.None));
        }

        // ── Persistenz: Märkte je Plattform ───────────────────────────────────

        [Fact]
        public void Same_market_id_on_two_platforms_is_stored_twice_and_reads_stay_global()
        {
            var repo = new EfMarketRepository(new InMemoryContextFactory<CoreDbContext>(o => new CoreDbContext(o)));
            repo.Upsert(new MarketData { Id = "42", Question = "global", ClobTokenIds = "[\"tok\"]" });
            repo.Upsert(new MarketData { Id = "42", Question = "us", ClobTokenIds = "[\"tok\"]", Platform = PlatformId.PolymarketUsValue });

            Assert.Equal("global", repo.GetById("42")!.Question);
            Assert.Equal("global", repo.FindByTokenId("tok")!.Question);
            Assert.Equal("global", Assert.Single(repo.GetActive()).Question);

            repo.Update(new MarketData { Id = "42", Question = "us2", Platform = PlatformId.PolymarketUsValue });
            Assert.Equal("global", repo.GetById("42")!.Question);
        }

        // ── Hilfen ────────────────────────────────────────────────────────────

        private static OrderRequest Buy(string token, decimal price, decimal usd) => new()
        {
            Instrument = InstrumentRef.PolymarketGlobal(token),
            Side = OrderSide.Buy,
            LimitPrice = price,
            NotionalUsd = usd
        };

        private static PolymarketGlobalAdapter NewGlobalAdapter(FakeClobClient clob, IMarketRepository markets) =>
            new(new NullCatalog(), new NullBook(), new GlobalOrderGateway(clob, markets), new NullPortfolio(), new GlobalFeeModel());

        private sealed class StubMarketRepository : IMarketRepository
        {
            private readonly List<MarketData> _markets;
            public StubMarketRepository(params MarketData[] markets) => _markets = markets.ToList();
            public MarketData? GetById(string id) => _markets.FirstOrDefault(m => m.Id == id);
            public MarketData? FindByTokenId(string tokenId) => _markets.FirstOrDefault(m => m.ClobTokenIds.Contains(tokenId));
            public List<MarketData> GetActive() => _markets.Where(m => !m.Closed).ToList();
            public void Upsert(MarketData market) { }
            public void Insert(MarketData market) { }
            public void Update(MarketData market) { }
            public void EnsureIndexes() { }
        }

        private sealed class NullCatalog : IMarketCatalog
        {
            public Task<IReadOnlyList<PlatformMarket>> GetRecentMarketsAsync(int limit, CancellationToken ct = default) =>
                Task.FromResult<IReadOnlyList<PlatformMarket>>(Array.Empty<PlatformMarket>());
            public Task<PlatformMarket?> GetMarketAsync(InstrumentRef instrument, CancellationToken ct = default) =>
                Task.FromResult<PlatformMarket?>(null);
            public Task<MarketResolution> GetResolutionAsync(InstrumentRef instrument, CancellationToken ct = default) =>
                Task.FromResult(MarketResolution.Open);
        }

        private sealed class NullBook : IOrderBookSource
        {
            public Task<decimal?> GetBestPriceAsync(InstrumentRef instrument, OrderSide side, CancellationToken ct = default) =>
                Task.FromResult<decimal?>(null);
        }

        private sealed class NullPortfolio : IPortfolioSource
        {
            public Task<decimal> GetAvailableBalanceAsync(AccountState account, CancellationToken ct = default) => Task.FromResult(0m);
            public Task<IReadOnlyList<PlatformPosition>?> GetPositionsAsync(AccountState account, CancellationToken ct = default) =>
                Task.FromResult<IReadOnlyList<PlatformPosition>?>(Array.Empty<PlatformPosition>());
        }
    }
}