using System.Text.Json;
using ClawdDotNet.Core.Files;
using ClawdDotNet.Core.Staging;
using ClawdDotNet.Core.Storage;
using ClawdDotNet.Core.Tools;
using ClawdDotNet.Tools.FileRW;
using Microsoft.Extensions.Logging.Abstractions;
using Shouldly;

namespace ClawdDotNet.Tools.Tests.FileRW;

/// <summary>
/// #195: The file history keeps what a delete removes, so deleting a file is no irreversible
/// act any more and needs no approval. A folder at once, or a file the history cannot keep,
/// still goes to a human; the workspace itself is never deleted; and an agent can see and undo
/// what was deleted. Test instance 2026-10-01: eleven cleanup deletes waited for the human.
/// </summary>
public sealed class ReversibleDeleteTests : IDisposable
{
    private readonly string _instance = Path.Combine(Path.GetTempPath(), "clawd-tests", "rd-" + Guid.NewGuid().ToString("N")[..8]);
    private readonly string _agents;
    private readonly string _shared;
    private readonly FileHistorySettings _settings = new();
    private readonly FileHistory _history;
    private readonly FileRWTool _tool = new();

    public ReversibleDeleteTests()
    {
        _agents = Path.Combine(_instance, "Agents");
        _shared = Path.Combine(_agents, "SharedWorkspace");
        Directory.CreateDirectory(_shared);
        _history = new FileHistory(_agents, new SqliteStorage(Path.Combine(_instance, "state.db")), () => _settings);
    }

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

    private AgentToolContext Context(string agentId = "keeper", bool history = true)
    {
        var personal = Path.Combine(_agents, "Agent-" + agentId, "Workspace");
        Directory.CreateDirectory(personal);
        return new AgentToolContext(agentId, "inst",
            new Dictionary<string, object?> { ["sharedAccessLevel"] = "Admin", ["sharedAllowedExtensions"] = JsonSerializer.SerializeToElement(new[] { ".txt", ".md" }) },
            new NullStateStore(), NullLogger.Instance, CancellationToken.None,
            WorkspacePath: personal, SharedWorkspacePath: _shared)
        {
            History = history ? _history : null,
            RunId = "run-" + agentId
        };
    }

    private Task<ToolResult> Run(object input, AgentToolContext? context = null)
        => _tool.ExecuteAsync(JsonSerializer.SerializeToElement(input), context ?? Context(), CancellationToken.None);

    private string? KeyOf(object input, AgentToolContext? context = null)
        => _tool.StagingAktion(JsonSerializer.SerializeToElement(input), context ?? Context());

    private void Put(string relative, string content = "x")
    {
        var full = Path.Combine(_shared, relative);
        Directory.CreateDirectory(Path.GetDirectoryName(full)!);
        File.WriteAllText(full, content);
    }

    [Fact]
    public async Task A_kept_file_is_deleted_without_approval_and_put_back_by_the_agent()
    {
        Put("wetter/stunden/berlin_00.txt", "13.4 °C");
        var delete = new { action = "delete", workspace = "shared", path = "wetter/stunden/berlin_00.txt" };

        KeyOf(delete).ShouldBe("delete");
        _tool.Vorgabe("delete", Context()).ShouldBe(StagingDecision.Auto);

        var deleted = await Run(delete);
        deleted.Success.ShouldBeTrue(deleted.ErrorMessage);
        deleted.Content.ShouldContain("can be restored for 90 days");

        var list = await Run(new { action = "deleted", workspace = "shared" });
        list.Content.ShouldContain("wetter/stunden/berlin_00.txt");
        var entry = (await _history.ListAsync("shared", null, null, null, 10, default)).First(e => e.Action == FileAction.Delete).Id;

        var restored = await Run(new { action = "restore", workspace = "shared", entry });
        restored.Success.ShouldBeTrue(restored.ErrorMessage);
        File.ReadAllText(Path.Combine(_shared, "wetter/stunden/berlin_00.txt")).ShouldBe("13.4 °C");

        (await Run(new { action = "restore", workspace = "shared", entry })).ErrorMessage.ShouldContain("exists again");
        (await Run(new { action = "deleted", workspace = "shared" })).Content.ShouldContain("Nothing deleted");
    }

    [Fact]
    public async Task A_folder_needs_recursive_and_a_human_and_the_workspace_is_never_deleted()
    {
        Put("archiv/a.txt");
        Put("archiv/b.txt");

        KeyOf(new { action = "delete", workspace = "shared", path = "archiv" }).ShouldBe("delete_folder");
        KeyOf(new { action = "delete", workspace = "shared", path = "archiv", recursive = true }).ShouldBe("delete_folder");
        new StagingPolicy().Decide("FileRW", "delete_folder").ShouldBe(StagingDecision.Approve);

        (await Run(new { action = "delete", workspace = "shared", path = "archiv" })).ErrorMessage.ShouldContain("recursive");
        (await Run(new { action = "delete", workspace = "shared", path = "." })).ErrorMessage.ShouldContain("workspace itself cannot be deleted");
        Directory.Exists(Path.Combine(_shared, "archiv")).ShouldBeTrue();

        (await Run(new { action = "delete", workspace = "shared", path = "archiv", recursive = true })).Success.ShouldBeTrue();
        Directory.Exists(Path.Combine(_shared, "archiv")).ShouldBeFalse();
    }

    [Fact]
    public void A_file_the_history_cannot_keep_stays_with_a_human()
    {
        Put("big.txt", new string('x', 2048));

        KeyOf(new { action = "delete", workspace = "shared", path = "big.txt" }, Context(history: false)).ShouldBe("delete_unkept");
        _tool.Vorgabe("delete", Context(history: false)).ShouldBeNull("without a history, the standard rule asks a human");

        _settings.MaxObjectMegabytes = 0;
        KeyOf(new { action = "delete", workspace = "shared", path = "big.txt" }).ShouldBe("delete_unkept");
        new StagingPolicy().Decide("FileRW", "delete_unkept").ShouldBe(StagingDecision.Approve);
        new StagingPolicy().Decide("FileRW", "delete").ShouldBe(StagingDecision.Approve, "without the history's word, delete stays with a human");
    }

    [Fact]
    public async Task A_deletion_from_another_workspace_or_with_a_forbidden_extension_is_not_restored()
    {
        Put("note.txt", "shared note");
        await Run(new { action = "delete", workspace = "shared", path = "note.txt" });
        var entry = (await _history.ListAsync("shared", null, null, null, 10, default)).First(e => e.Action == FileAction.Delete).Id;

        (await Run(new { action = "restore", workspace = "personal", entry })).ErrorMessage.ShouldContain("no deletion in the personal workspace");
        (await Run(new { action = "restore", workspace = "shared" })).ErrorMessage.ShouldContain("'entry' is required");

        // A file whose extension the workspace no longer allows does not come back through restore.
        Put("tool.exe", "MZ");
        var exe = await _history.BeforeAsync(Path.Combine(_shared, "tool.exe"), "shared", default);
        File.Delete(Path.Combine(_shared, "tool.exe"));
        var recorded = await _history.RecordAsync(exe, FileAction.Delete, "someone", null, default);
        (await Run(new { action = "restore", workspace = "shared", entry = recorded!.Id })).Success.ShouldBeFalse();
        File.Exists(Path.Combine(_shared, "tool.exe")).ShouldBeFalse();
    }
}