using AcDream.Core.Chat;

namespace AcDream.Core.Tests.Chat;

/// <summary>
/// Phase J follow-up: ACE often sends the same system text via two
/// wire paths (GameMessageSystemChat 0xF7E0 + GameEventCommunication-
/// TransientString 0x02EB) for back-compat — both get routed to
/// <see cref="ChatLog.OnSystemMessage"/> in our wiring, which would
/// double-print every system line. Dedupe consecutive identical
/// system text within a short window.
/// </summary>
public sealed class ChatLogSystemDedupTests
{
    [Fact]
    public void OnSystemMessage_ImmediateDuplicate_OnlyOneEntry()
    {
        var log = new ChatLog();
        log.OnSystemMessage("Unknown command: help", chatType: 0);
        log.OnSystemMessage("Unknown command: help", chatType: 0);

        // Second identical message arrived <1s later — suppressed.
        Assert.Single(log.Snapshot());
    }

    [Fact]
    public void OnSystemMessage_DifferentText_BothEntries()
    {
        var log = new ChatLog();
        log.OnSystemMessage("Welcome to Asheron's Call", chatType: 0);
        log.OnSystemMessage("Use @acecommands to get a complete list of commands.", chatType: 0);

        // Different text — both retained even back-to-back.
        Assert.Equal(2, log.Snapshot().Length);
    }

    [Fact]
    public void OnSystemMessage_TripletDuplicate_StillOnlyOneEntry()
    {
        var log = new ChatLog();
        log.OnSystemMessage("Unknown command: help", chatType: 0);
        log.OnSystemMessage("Unknown command: help", chatType: 0);
        log.OnSystemMessage("Unknown command: help", chatType: 0);

        Assert.Single(log.Snapshot());
    }

    [Fact]
    public void OnSystemMessage_DuplicateBookendingNonDuplicate_KeepsBothUnique()
    {
        var log = new ChatLog();
        log.OnSystemMessage("Unknown command: help", chatType: 0);
        log.OnSystemMessage("Welcome to Asheron's Call", chatType: 0);
        log.OnSystemMessage("Unknown command: help", chatType: 0);

        // First "Unknown..." retained, "Welcome..." retained, second
        // "Unknown..." is no longer the *immediate* duplicate (the
        // most-recent entry is "Welcome..."), so it's kept too.
        Assert.Equal(3, log.Snapshot().Length);
    }
}