using NeonSprawl.Server.Game.Factions;
using Xunit;

namespace NeonSprawl.Server.Tests.Game.Factions;

public sealed class InMemoryReputationDeltaStoreTests
{
    private const string PlayerId = "dev-local-1";
    private const string GridFactionId = "prototype_faction_grid_operators";
    private static readonly DateTimeOffset RecordedAt = new(2026, 6, 15, 12, 0, 0, TimeSpan.Zero);

    [Fact]
    public void TryAppend_ShouldReturnTrueAndQueryRow_WhenFirstAppend()
    {
        // Arrange
        var store = CreateStore();
        var row = CreateRow("delta-001", 15, 15);
        // Act
        var appended = store.TryAppend(row);
        var rows = store.GetDeltasForPlayer(PlayerId);
        // Assert
        Assert.True(appended);
        var read = Assert.Single(rows);
        Assert.Equal(row.Id, read.Id);
        Assert.Equal(15, read.DeltaAmount);
        Assert.Equal(15, read.ResultingStanding);
    }

    [Fact]
    public void TryAppend_ShouldReturnFalse_WhenDuplicateId()
    {
        // Arrange
        var store = CreateStore();
        var row = CreateRow("delta-dup", 10, 10);
        Assert.True(store.TryAppend(row));
        // Act
        var duplicate = store.TryAppend(row with { DeltaAmount = 99, ResultingStanding = 99 });
        // Assert
        Assert.False(duplicate);
        var read = Assert.Single(store.GetDeltasForPlayer(PlayerId));
        Assert.Equal(10, read.DeltaAmount);
    }

    [Fact]
    public void TryAppend_ShouldReturnTrueTwice_WhenDistinctIds()
    {
        // Arrange
        var store = CreateStore();
        // Act
        var first = store.TryAppend(CreateRow("delta-a", 15, 15));
        var second = store.TryAppend(CreateRow("delta-b", 10, 25));
        // Assert
        Assert.True(first);
        Assert.True(second);
        Assert.Equal(2, store.GetDeltasForPlayer(PlayerId).Count);
    }

    [Fact]
    public void TryAppend_ShouldReturnFalse_WhenRowInvalid()
    {
        // Arrange
        var store = CreateStore();
        var emptyId = CreateRow("", 5, 5);
        var emptyPlayer = CreateRow("delta-x", 5, 5) with { PlayerId = "  " };
        var emptyFaction = CreateRow("delta-y", 5, 5) with { FactionId = "" };
        // Act
        var noId = store.TryAppend(emptyId);
        var noPlayer = store.TryAppend(emptyPlayer);
        var noFaction = store.TryAppend(emptyFaction);
        // Assert
        Assert.False(noId);
        Assert.False(noPlayer);
        Assert.False(noFaction);
        Assert.Empty(store.GetDeltasForPlayer(PlayerId));
    }

    [Fact]
    public void GetDeltasForPlayer_ShouldOrderByRecordedAtThenId()
    {
        // Arrange
        var store = CreateStore();
        Assert.True(store.TryAppend(CreateRow("delta-z", 1, 1) with { RecordedAt = RecordedAt.AddMinutes(2) }));
        Assert.True(store.TryAppend(CreateRow("delta-a", 2, 3) with { RecordedAt = RecordedAt }));
        Assert.True(store.TryAppend(CreateRow("delta-m", 3, 6) with { RecordedAt = RecordedAt }));
        // Act
        var rows = store.GetDeltasForPlayer(PlayerId);
        // Assert
        Assert.Equal(["delta-a", "delta-m", "delta-z"], rows.Select(static r => r.Id).ToArray());
    }

    [Fact]
    public void GetDeltasForPlayer_ShouldRespectLimit_WhenProvided()
    {
        // Arrange
        var store = CreateStore();
        Assert.True(store.TryAppend(CreateRow("delta-1", 1, 1)));
        Assert.True(store.TryAppend(CreateRow("delta-2", 1, 2)));
        // Act
        var rows = store.GetDeltasForPlayer(PlayerId, limit: 1);
        // Assert
        Assert.Single(rows);
        Assert.Equal("delta-1", rows[0].Id);
    }

    private static InMemoryReputationDeltaStore CreateStore() => new();

    private static ReputationDeltaRow CreateRow(string id, int delta, int resulting) =>
        new(
            id,
            PlayerId,
            GridFactionId,
            delta,
            resulting,
            ReputationDeltaSourceKinds.QuestCompletion,
            "prototype_quest_operator_chain",
            RecordedAt);
}