using ClawdDotNet.Core.Engine;
using ClawdDotNet.Core.Tests.Infrastructure;

namespace ClawdDotNet.Core.Tests.Engine;

/// <summary>
/// What an abort in the middle of a turn does to the conversation context.
///
/// The context is a shared list, changed in place. If a run aborts
/// between the tool call and its answer, an assistant message
/// with tool_calls remains that no answer follows — a message sequence the
/// interface does not accept.
/// </summary>
public class AbbruchKontextTests
{
    [Fact]
    public async Task Ein_Abbruch_waehrend_des_Werkzeugs_hinterlaesst_keinen_unbeantworteten_Aufruf()
    {
        var fixture = new EngineFixture().WithTool(
            FakeTool.Slow(TimeSpan.FromSeconds(5), name: "LangsamTool"));

        var agent = fixture.AddAgent("a1", "LangsamTool");

        fixture.Client
            .RespondsWithToolCall("LangsamTool")
            .AlwaysRespondsWithText("Fertig.");

        var lauf = fixture.Engine.ChatAsync(agent, "Los", "inst", CancellationToken.None);

        // Wait until the call is surely in place and the tool is running.
        await Task.Delay(300);
        fixture.Engine.AbortChat("a1");

        var result = await lauf;
        Assert.Equal(AgentRunStatus.Cancelled, result.Status);

        var kontext = fixture.Engine.GetChatContext("a1");

        var offeneAufrufe = kontext
            .Where(m => m.Role == "assistant" && m.ToolCalls is { Count: > 0 })
            .SelectMany(m => m.ToolCalls!)
            .Select(tc => tc.Id)
            .Where(id => !kontext.Any(m => m.Role == "tool" && m.ToolCallId == id))
            .ToList();

        Assert.True(offeneAufrufe.Count == 0,
            $"Unbeantwortete Werkzeugaufrufe im Kontext: {string.Join(", ", offeneAufrufe)}. " +
            "Eine solche Folge lehnt die Schnittstelle mit HTTP 400 ab — der Agent ist " +
            "danach dauerhaft blockiert.");

        // The substitute answer also says what happened. An empty answer would be formally
        // valid, but would leave the model puzzling why its call yielded nothing.
        var ersatz = kontext.Last(m => m.Role == "tool");
        Assert.Contains("abgebrochen", ersatz.Content, StringComparison.OrdinalIgnoreCase);
    }

    [Fact]
    public async Task Nach_einem_Abbruch_laesst_sich_der_Agent_wieder_ansprechen()
    {
        // The actual point: not the form of the context counts, but whether the
        // agent still works afterwards. A second chat has to run through.
        var fixture = new EngineFixture().WithTool(
            FakeTool.Slow(TimeSpan.FromSeconds(5), name: "LangsamTool"));

        var agent = fixture.AddAgent("a1", "LangsamTool");

        fixture.Client
            .RespondsWithToolCall("LangsamTool")
            .AlwaysRespondsWithText("Zweite Antwort.");

        var erster = fixture.Engine.ChatAsync(agent, "Los", "inst", CancellationToken.None);
        await Task.Delay(300);
        fixture.Engine.AbortChat("a1");
        await erster;

        var zweiter = await fixture.Engine.ChatAsync(agent, "Und jetzt?", "inst", CancellationToken.None);

        Assert.Equal(AgentRunStatus.Completed, zweiter.Status);
        Assert.Equal("Zweite Antwort.", zweiter.FinalMessage);

        // And the sequence that was sent in doing so was completely answered.
        var gesendet = fixture.Client.ReceivedRequests[^1].Messages;
        var offen = gesendet
            .Where(m => m.Role == "assistant" && m.ToolCalls is { Count: > 0 })
            .SelectMany(m => m.ToolCalls!)
            .Select(tc => tc.Id)
            .Where(id => !gesendet.Any(m => m.Role == "tool" && m.ToolCallId == id))
            .ToList();

        Assert.Empty(offen);
    }
}