using ClawdDotNet.Core.Config;
using ClawdDotNet.Core.Organisation;
using ClawdDotNet.Core.Storage;
using ClawdDotNet.Core.Tasks;
using ClawdDotNet.Core.Tests.Infrastructure;
using Shouldly;

namespace ClawdDotNet.Core.Tests.Tasks;

/// <summary>
/// #714: Every task can say what it serves, up to the goal of its unit — and the run of a
/// task is told so.
/// </summary>
public sealed class GoalChainTests : IDisposable
{
    private readonly string _directory = Path.Combine(Path.GetTempPath(), "clawd-tests", "goal-" + Guid.NewGuid().ToString("N")[..8]);
    private readonly SqliteTaskRepository _repo;

    public GoalChainTests()
    {
        _repo = new SqliteTaskRepository(new SqliteStorage(Path.Combine(_directory, "state.db")));
    }

    public void Dispose()
    {
        SqliteStorage.ReleasePooledConnections(_directory);
        try { Directory.Delete(_directory, recursive: true); }
        catch { /* cleaning up is secondary */ }
    }

    private Task<TaskItem> Save(string id, string title, string parent = "", string assignee = "@ads")
        => _repo.UpsertAsync(new TaskItem { Id = id, Title = title, ParentId = parent, Assignee = assignee }, default);

    private static OrgChart Shop(string marketingGoal = "Grow revenue profitably.", string amazonGoal = "") => new(
        [
            new UnitConfig { Id = "marketing", Name = "Marketing", Goal = marketingGoal },
            new UnitConfig { Id = "amazon", Name = "Amazon", ParentId = "marketing", Goal = amazonGoal }
        ],
        [new AgentConfig { AgentId = "ads", UnitId = "amazon" }]);

    [Fact]
    public async Task The_parents_are_walked_nearest_first()
    {
        await Save("t-1", "Spring collection");
        await Save("t-2", "Listings for the collection", "t-1");
        var leaf = await Save("t-3", "Text for chair A-100", "t-2");

        var parents = await GoalChain.ParentsAsync(leaf, _repo.GetAsync, default);

        parents.Select(p => p.Id).ShouldBe(["t-2", "t-1"]);
    }

    [Fact]
    public async Task A_cycle_in_the_data_does_not_hang_the_walk()
    {
        await Save("t-1", "A", "t-2");
        var b = await Save("t-2", "B", "t-1");

        (await GoalChain.ParentsAsync(b, _repo.GetAsync, default)).Select(p => p.Id).ShouldBe(["t-1"]);
    }

    [Fact]
    public async Task A_task_cannot_be_put_below_itself()
    {
        await Save("t-1", "Top");
        await Save("t-2", "Middle", "t-1");
        await Save("t-3", "Bottom", "t-2");

        (await GoalChain.WouldCycleAsync("t-1", "t-3", _repo.GetAsync, default)).ShouldBeTrue();
        (await GoalChain.WouldCycleAsync("t-1", "t-1", _repo.GetAsync, default)).ShouldBeTrue();
        (await GoalChain.WouldCycleAsync("t-3", "t-1", _repo.GetAsync, default)).ShouldBeFalse();
    }

    [Fact]
    public async Task The_description_ends_in_the_goal_of_the_nearest_unit_that_has_one()
    {
        var top = await Save("t-1", "Spring collection");
        var leaf = await Save("t-2", "Text for chair A-100", "t-1");

        var text = GoalChain.Describe(leaf, [top], Shop())!;

        text.ShouldContain("t-1 \"Spring collection\"");
        // amazon has no goal of its own — the one of marketing above it counts.
        text.ShouldContain("the goal of the unit \"Marketing\": Grow revenue profitably.");
    }

    [Fact]
    public void Without_parents_and_without_a_goal_nothing_is_added()
    {
        GoalChain.Describe(new TaskItem { Id = "t-9", Assignee = "@ads" }, [], Shop(marketingGoal: "")).ShouldBeNull();
        GoalChain.Describe(new TaskItem { Id = "t-9", Assignee = "@ads" }, [], null).ShouldBeNull();
    }

    [Fact]
    public async Task The_parent_survives_the_file_and_a_re_import()
    {
        var tasksDir = Path.Combine(_directory, "tasks");
        var board = new TaskboardService(_repo, tasksDir);
        await board.CreateAsync(new TaskItem { Id = "t-1", Title = "Top" }, default);
        await board.CreateAsync(new TaskItem { Id = "t-2", Title = "Below", ParentId = "t-1" }, default);

        Directory.GetFiles(tasksDir).Select(File.ReadAllText).Single(text => text.Contains("id: t-2"))
            .ShouldContain("parent: t-1");
        await board.ImportAllAsync(default);

        (await _repo.GetAsync("t-2", default))!.ParentId.ShouldBe("t-1");
    }

    [Fact]
    public async Task The_run_of_a_task_is_told_why()
    {
        var fixture = new EngineFixture();
        var agent = fixture.AddAgent("ads");
        agent.UnitId = "amazon";
        fixture.Engine.OrganisationProvider = () => new OrgChart(
            [
                new UnitConfig { Id = "marketing", Name = "Marketing", Goal = "Grow revenue profitably." },
                new UnitConfig { Id = "amazon", Name = "Amazon", ParentId = "marketing" }
            ],
            fixture.Agents);
        fixture.Client.RespondsWithText("ERGEBNIS: ok");

        await Save("t-1", "Spring collection", assignee: "@human");
        var leaf = await Save("t-2", "Text for chair A-100", "t-1");

        var dispatcher = new EngineTaskDispatcher(
            fixture.Engine, () => fixture.Agents, "test-instance", fixture.Registry, fixture.StateStore, TestLogging.Factory,
            tasks: _repo);
        await dispatcher.DispatchAsync(leaf, default);

        var message = fixture.Client.ReceivedRequests[0].Messages.Last(m => m.Role == "user").Content!;
        message.ShouldContain("Why this task exists");
        message.ShouldContain("t-1 \"Spring collection\"");
        message.ShouldContain("Grow revenue profitably.");
    }
}