using NeonSprawl.Server.Game.Contracts;
using NeonSprawl.Server.Game.PositionState;

namespace NeonSprawl.Server.Tests.Game.Contracts;

public sealed class InMemoryContractInstanceStoreTests
{
    private const string PlayerId = "dev-local-1";
    private const string UnknownPlayerId = "unknown-player-xyz";
    private const string InstanceId = "prototype_contract_instance_001";
    private const string SecondInstanceId = "prototype_contract_instance_002";
    private const string TemplateId = "prototype_contract_clear_combat_pocket";
    private const string SeedBucket = "2026-06-22";
    private static readonly DateTimeOffset IssuedAt = new(2026, 6, 22, 10, 0, 0, TimeSpan.Zero);
    private static readonly DateTimeOffset CompletedAt = new(2026, 6, 22, 12, 0, 0, TimeSpan.Zero);

    [Fact]
    public void TryGet_ShouldReturnFalse_WhenRowMissing()
    {
        // Arrange
        var store = CreateStore();
        // Act
        var found = store.TryGet(PlayerId, InstanceId, out _);
        // Assert
        Assert.False(found);
    }

    [Fact]
    public void TryCreateActive_ShouldPersistAllFields()
    {
        // Arrange
        var store = CreateStore();
        // Act
        var created = store.TryCreateActive(
            PlayerId,
            InstanceId,
            TemplateId,
            SeedBucket,
            IssuedAt,
            out var snapshot);
        // Assert
        Assert.True(created);
        Assert.Equal(InstanceId, snapshot.ContractInstanceId);
        Assert.Equal(TemplateId, snapshot.TemplateId);
        Assert.Equal(PlayerId, snapshot.PlayerId);
        Assert.Equal(ContractInstanceStatus.Active, snapshot.Status);
        Assert.Equal(SeedBucket, snapshot.SeedBucket);
        Assert.Equal(IssuedAt, snapshot.IssuedAt);
        Assert.Null(snapshot.CompletedAt);
    }

    [Fact]
    public void TryCreateActive_ShouldDenyDuplicateInstanceId()
    {
        // Arrange
        var store = CreateStore();
        Assert.True(store.TryCreateActive(
            PlayerId,
            InstanceId,
            TemplateId,
            SeedBucket,
            IssuedAt,
            out var firstSnapshot));
        // Act
        var duplicate = store.TryCreateActive(
            PlayerId,
            InstanceId,
            TemplateId,
            SeedBucket,
            IssuedAt.AddHours(1),
            out var secondSnapshot);
        // Assert
        Assert.False(duplicate);
        Assert.Equal(firstSnapshot.ContractInstanceId, secondSnapshot.ContractInstanceId);
        Assert.Equal(firstSnapshot.IssuedAt, secondSnapshot.IssuedAt);
        Assert.Equal(ContractInstanceStatus.Active, secondSnapshot.Status);
    }

    [Fact]
    public void TryCreateActive_ShouldDenySecondActiveForSamePlayer()
    {
        // Arrange
        var store = CreateStore();
        Assert.True(store.TryCreateActive(
            PlayerId,
            InstanceId,
            TemplateId,
            SeedBucket,
            IssuedAt,
            out _));
        // Act
        var second = store.TryCreateActive(
            PlayerId,
            SecondInstanceId,
            TemplateId,
            SeedBucket,
            IssuedAt.AddHours(1),
            out var snapshot);
        // Assert
        Assert.False(second);
        Assert.Equal(InstanceId, snapshot.ContractInstanceId);
        Assert.Equal(ContractInstanceStatus.Active, snapshot.Status);
        Assert.True(store.TryGetActiveForPlayer(PlayerId, out var active));
        Assert.Equal(InstanceId, active.ContractInstanceId);
    }

    [Fact]
    public void TryMarkComplete_ShouldSetCompletedStatusAndTimestamp()
    {
        // Arrange
        var store = CreateStore();
        Assert.True(store.TryCreateActive(
            PlayerId,
            InstanceId,
            TemplateId,
            SeedBucket,
            IssuedAt,
            out _));
        // Act
        var completed = store.TryMarkComplete(PlayerId, InstanceId, CompletedAt, out var snapshot);
        // Assert
        Assert.True(completed);
        Assert.Equal(ContractInstanceStatus.Completed, snapshot.Status);
        Assert.Equal(CompletedAt, snapshot.CompletedAt);
        Assert.False(store.TryGetActiveForPlayer(PlayerId, out _));
    }

    [Fact]
    public void TryMarkComplete_ShouldBeIdempotent()
    {
        // Arrange
        var store = CreateStore();
        Assert.True(store.TryCreateActive(
            PlayerId,
            InstanceId,
            TemplateId,
            SeedBucket,
            IssuedAt,
            out _));
        // Act
        var first = store.TryMarkComplete(PlayerId, InstanceId, CompletedAt, out var firstSnapshot);
        var second = store.TryMarkComplete(
            PlayerId,
            InstanceId,
            CompletedAt.AddHours(1),
            out var secondSnapshot);
        // Assert
        Assert.True(first);
        Assert.False(second);
        Assert.Equal(ContractInstanceStatus.Completed, secondSnapshot.Status);
        Assert.Equal(CompletedAt, secondSnapshot.CompletedAt);
        Assert.Equal(firstSnapshot.TemplateId, secondSnapshot.TemplateId);
    }

    [Fact]
    public void TryCreateActive_ShouldAllowNewInstanceAfterComplete()
    {
        // Arrange
        var store = CreateStore();
        Assert.True(store.TryCreateActive(
            PlayerId,
            InstanceId,
            TemplateId,
            SeedBucket,
            IssuedAt,
            out _));
        Assert.True(store.TryMarkComplete(PlayerId, InstanceId, CompletedAt, out _));
        // Act
        var reissued = store.TryCreateActive(
            PlayerId,
            SecondInstanceId,
            TemplateId,
            SeedBucket,
            IssuedAt.AddDays(1),
            out var snapshot);
        // Assert
        Assert.True(reissued);
        Assert.Equal(SecondInstanceId, snapshot.ContractInstanceId);
        Assert.Equal(ContractInstanceStatus.Active, snapshot.Status);
    }

    [Fact]
    public void TryCreateActive_ShouldReturnFalse_ForUnknownPlayer()
    {
        // Arrange
        var store = CreateStore();
        // Act
        var created = store.TryCreateActive(
            UnknownPlayerId,
            InstanceId,
            TemplateId,
            SeedBucket,
            IssuedAt,
            out _);
        // Assert
        Assert.False(created);
    }

    [Theory]
    [InlineData("", InstanceId, TemplateId, SeedBucket)]
    [InlineData("   ", InstanceId, TemplateId, SeedBucket)]
    [InlineData(PlayerId, "", TemplateId, SeedBucket)]
    [InlineData(PlayerId, "   ", TemplateId, SeedBucket)]
    [InlineData(PlayerId, InstanceId, "", SeedBucket)]
    [InlineData(PlayerId, InstanceId, TemplateId, "")]
    public void TryCreateActive_ShouldReturnFalse_WhenRequiredIdsEmpty(
        string playerId,
        string instanceId,
        string templateId,
        string seedBucket)
    {
        // Arrange
        var store = CreateStore();
        // Act
        var created = store.TryCreateActive(
            playerId,
            instanceId,
            templateId,
            seedBucket,
            IssuedAt,
            out _);
        // Assert
        Assert.False(created);
    }

    [Fact]
    public async Task TryCreateActiveAndTryMarkComplete_ShouldKeepActiveIndexConsistent_WhenRacingOnSameInstanceId()
    {
        // Arrange
        var store = CreateStore();
        // Act
        await Task.WhenAll(
            Enumerable.Range(0, 32).Select(i => Task.Run(() =>
            {
                if (i % 2 == 0)
                {
                    _ = store.TryCreateActive(
                        PlayerId,
                        InstanceId,
                        TemplateId,
                        SeedBucket,
                        IssuedAt,
                        out _);
                    return;
                }

                _ = store.TryMarkComplete(PlayerId, InstanceId, CompletedAt, out _);
            })));

        // Assert
        if (store.TryGetActiveForPlayer(PlayerId, out var active))
        {
            Assert.True(store.TryGet(PlayerId, active.ContractInstanceId, out var row));
            Assert.Equal(ContractInstanceStatus.Active, row.Status);
        }

        if (store.TryGet(PlayerId, InstanceId, out var final) &&
            final.Status == ContractInstanceStatus.Completed)
        {
            Assert.False(store.TryGetActiveForPlayer(PlayerId, out _));
        }
    }

    [Fact]
    public async Task TryGetActiveForPlayer_ShouldKeepActiveIndexConsistent_WhenRacingWithCompleteAndReissue()
    {
        // Arrange
        var store = CreateStore();
        Assert.True(store.TryCreateActive(
            PlayerId,
            InstanceId,
            TemplateId,
            SeedBucket,
            IssuedAt,
            out _));
        // Act
        await Task.WhenAll(
            Enumerable.Range(0, 32).Select(i => Task.Run(() =>
            {
                if (i % 3 == 0)
                {
                    _ = store.TryGetActiveForPlayer(PlayerId, out _);
                    return;
                }

                if (i % 3 == 1)
                {
                    _ = store.TryMarkComplete(PlayerId, InstanceId, CompletedAt, out _);
                    return;
                }

                _ = store.TryCreateActive(
                    PlayerId,
                    SecondInstanceId,
                    TemplateId,
                    SeedBucket,
                    IssuedAt.AddDays(1),
                    out _);
            })));

        // Assert
        if (store.TryGetActiveForPlayer(PlayerId, out var active))
        {
            Assert.True(store.TryGet(PlayerId, active.ContractInstanceId, out var row));
            Assert.Equal(ContractInstanceStatus.Active, row.Status);
        }

        Assert.False(
            store.TryGet(PlayerId, InstanceId, out var first) &&
            store.TryGet(PlayerId, SecondInstanceId, out var second) &&
            first.Status == ContractInstanceStatus.Active &&
            second.Status == ContractInstanceStatus.Active);
    }

    [Fact]
    public void ListForPlayer_ShouldReturnEmpty_WhenPlayerHasNoInstances()
    {
        // Arrange
        var store = CreateStore();
        // Act
        var rows = store.ListForPlayer(PlayerId, maxCompletedRows: 10);
        // Assert
        Assert.Empty(rows);
    }

    [Fact]
    public void ListForPlayer_ShouldReturnEmpty_ForUnknownPlayer()
    {
        // Arrange
        var store = CreateStore();
        // Act
        var rows = store.ListForPlayer(UnknownPlayerId, maxCompletedRows: 10);
        // Assert
        Assert.Empty(rows);
    }

    [Fact]
    public void ListForPlayer_ShouldReturnActiveOnly_WhenNoCompletedRows()
    {
        // Arrange
        var store = CreateStore();
        Assert.True(store.TryCreateActive(
            PlayerId,
            InstanceId,
            TemplateId,
            SeedBucket,
            IssuedAt,
            out _));
        // Act
        var rows = store.ListForPlayer(PlayerId, maxCompletedRows: 10);
        // Assert
        var row = Assert.Single(rows);
        Assert.Equal(InstanceId, row.ContractInstanceId);
        Assert.Equal(ContractInstanceStatus.Active, row.Status);
    }

    [Fact]
    public void ListForPlayer_ShouldReturnCompletedOrderedByIssuedAt_WhenNoActive()
    {
        // Arrange
        var store = CreateStore();
        Assert.True(store.TryCreateActive(
            PlayerId,
            InstanceId,
            TemplateId,
            SeedBucket,
            IssuedAt,
            out _));
        Assert.True(store.TryMarkComplete(PlayerId, InstanceId, CompletedAt, out _));
        Assert.True(store.TryCreateActive(
            PlayerId,
            SecondInstanceId,
            TemplateId,
            SeedBucket,
            IssuedAt.AddDays(1),
            out _));
        Assert.True(store.TryMarkComplete(
            PlayerId,
            SecondInstanceId,
            CompletedAt.AddDays(1),
            out _));
        // Act
        var rows = store.ListForPlayer(PlayerId, maxCompletedRows: 10);
        // Assert
        Assert.Equal(2, rows.Count);
        Assert.Equal(SecondInstanceId, rows[0].ContractInstanceId);
        Assert.Equal(InstanceId, rows[1].ContractInstanceId);
    }

    [Fact]
    public void ListForPlayer_ShouldPrependActiveAndCapCompletedRows()
    {
        // Arrange
        var store = CreateStore();
        for (var i = 0; i < 12; i++)
        {
            var instanceId = $"prototype_contract_instance_done_{i:D2}";
            Assert.True(store.TryCreateActive(
                PlayerId,
                instanceId,
                TemplateId,
                SeedBucket,
                IssuedAt.AddHours(i),
                out _));
            Assert.True(store.TryMarkComplete(
                PlayerId,
                instanceId,
                CompletedAt.AddHours(i),
                out _));
        }

        const string activeId = "prototype_contract_instance_active";
        Assert.True(store.TryCreateActive(
            PlayerId,
            activeId,
            TemplateId,
            SeedBucket,
            IssuedAt.AddDays(3),
            out _));

        // Act
        var rows = store.ListForPlayer(PlayerId, maxCompletedRows: 10);
        // Assert
        Assert.Equal(11, rows.Count);
        Assert.Equal(activeId, rows[0].ContractInstanceId);
        Assert.Equal(ContractInstanceStatus.Active, rows[0].Status);
        Assert.All(rows.Skip(1), row => Assert.Equal(ContractInstanceStatus.Completed, row.Status));
        Assert.DoesNotContain(
            rows.Skip(1),
            row => string.Equals(row.ContractInstanceId, "prototype_contract_instance_done_00", StringComparison.Ordinal));
        Assert.DoesNotContain(
            rows.Skip(1),
            row => string.Equals(row.ContractInstanceId, "prototype_contract_instance_done_01", StringComparison.Ordinal));
    }

    [Fact]
    public void TryClearInstance_ShouldReturnTrue_WhenRowMissing()
    {
        // Arrange
        var store = CreateStore();
        // Act
        var cleared = store.TryClearInstance(PlayerId, InstanceId);
        // Assert
        Assert.True(cleared);
        Assert.False(store.TryGet(PlayerId, InstanceId, out _));
    }

    [Fact]
    public async Task Host_ShouldResolveContractInstanceStoresFromDi()
    {
        // Arrange
        await using var factory = new InMemoryWebApplicationFactory();
        using var scope = factory.Services.CreateScope();
        var instanceStore = scope.ServiceProvider.GetRequiredService<IContractInstanceStore>();
        var outcomeStore = scope.ServiceProvider.GetRequiredService<IContractOutcomeStore>();
        // Act
        var created = instanceStore.TryCreateActive(
            PlayerId,
            InstanceId,
            TemplateId,
            SeedBucket,
            IssuedAt,
            out var snapshot);
        // Assert
        Assert.IsType<InMemoryContractInstanceStore>(instanceStore);
        Assert.IsType<InMemoryContractOutcomeStore>(outcomeStore);
        Assert.True(created);
        Assert.Equal(TemplateId, snapshot.TemplateId);
    }

    private static InMemoryContractInstanceStore CreateStore()
    {
        var options = Options.Create(new GamePositionOptions { DevPlayerId = PlayerId });
        return new InMemoryContractInstanceStore(options);
    }
}