namespace AxCopilot.Services;

/// <summary>
/// Executes task-state tracking behind a single service boundary.
/// AppStateService and UI layers should prefer this service over direct store access.
/// </summary>
public sealed class TaskRunService
{
    public sealed class TaskSummaryState
    {
        public int ActiveCount { get; init; }
        public int PendingPermissionCount { get; init; }
        public TaskRunStore.TaskRun? LatestRecentTask { get; init; }
        public bool HasActiveTasks => ActiveCount > 0;
    }

    private readonly TaskRunStore _store;

    public TaskRunService()
        : this(new TaskRunStore())
    {
    }

    public TaskRunService(TaskRunStore store)
    {
        _store = store;
        _store.Changed += () => Changed?.Invoke();
    }

    public TaskRunStore Store => _store;
    public IReadOnlyList<TaskRunStore.TaskRun> ActiveTasks => _store.ActiveTasks;
    public IReadOnlyList<TaskRunStore.TaskRun> RecentTasks => _store.RecentTasks;

    public event Action? Changed;

    public void StartOrUpdate(string id, string kind, string title, string summary, string status = "running", string? filePath = null)
    {
        _store.Upsert(id, kind, title, summary, status, filePath);
    }

    public void Complete(string id, string? summary = null, string status = "completed")
    {
        _store.Complete(id, summary, status);
    }

    public void CompleteByPrefix(string prefix, string? summary = null, string status = "completed")
    {
        _store.CompleteByPrefix(prefix, summary, status);
    }

    public void RestoreRecent(IEnumerable<TaskRunStore.TaskRun>? recent)
    {
        _store.RestoreRecent(recent);
    }

    public void StartAgentRun(string runId, string summary)
    {
        var evt = new Agent.AgentEvent { RunId = runId };
        StartOrUpdate(GetAgentTaskKey(evt), "agent", "main", summary, "running");
    }

    public void CompleteAgentRun(string runId, string summary, bool success)
    {
        var evt = new Agent.AgentEvent { RunId = runId };
        Complete(GetAgentTaskKey(evt), summary, success ? "completed" : "failed");
    }

    public void StartToolRun(string runId, string toolName, string summary, string? filePath = null, bool skill = false)
    {
        var evt = new Agent.AgentEvent { RunId = runId, ToolName = toolName };
        StartOrUpdate(
            GetToolTaskKey(evt),
            skill ? "skill" : "tool",
            string.IsNullOrWhiteSpace(toolName) ? (skill ? "skill" : "tool") : toolName,
            summary,
            "running",
            filePath);
    }

    public void CompleteToolRun(string runId, string toolName, string summary, bool success)
    {
        var evt = new Agent.AgentEvent { RunId = runId, ToolName = toolName };
        Complete(GetToolTaskKey(evt), summary, success ? "completed" : "failed");
    }

    public void StartPermissionRequest(string runId, string toolName, string summary, string? filePath = null)
    {
        var evt = new Agent.AgentEvent { RunId = runId, ToolName = toolName };
        StartOrUpdate(
            GetPermissionTaskKey(evt),
            "permission",
            string.IsNullOrWhiteSpace(toolName) ? "permission request" : $"{toolName} permission",
            summary,
            "waiting",
            filePath);
    }

    public void CompletePermissionRequest(string runId, string toolName, string summary, bool granted)
    {
        var evt = new Agent.AgentEvent { RunId = runId, ToolName = toolName };
        Complete(GetPermissionTaskKey(evt), summary, granted ? "completed" : "failed");
    }

    public void RecordHookResult(string runId, string toolName, string summary, bool success, string? filePath = null)
    {
        var evt = new Agent.AgentEvent { RunId = runId, ToolName = toolName };
        StartOrUpdate(
            GetHookTaskKey(evt),
            "hook",
            string.IsNullOrWhiteSpace(toolName) ? "hook" : $"{toolName} hook",
            summary,
            "running",
            filePath);
        Complete(GetHookTaskKey(evt), summary, success ? "completed" : "failed");
    }

    public void StartBackgroundRun(string id, string title, string summary)
    {
        var taskId = BuildBackgroundTaskId(id);
        StartOrUpdate(taskId, "background", string.IsNullOrWhiteSpace(title) ? "background" : title, summary, "running");
    }

    public void CompleteBackgroundRun(string id, string title, string summary, bool success)
    {
        var taskId = BuildBackgroundTaskId(id);
        if (!ActiveTasks.Any(x => string.Equals(x.Id, taskId, StringComparison.OrdinalIgnoreCase)))
        {
            StartOrUpdate(taskId, "background", string.IsNullOrWhiteSpace(title) ? "background" : title, summary, "running");
        }

        Complete(taskId, summary, success ? "completed" : "failed");
    }

    public void StartQueueRun(string tab, string id, string summary)
    {
        var taskId = BuildQueueTaskId(tab, id);
        var title = string.IsNullOrWhiteSpace(tab) ? "queue" : $"{tab} queue";
        StartOrUpdate(taskId, "queue", title, summary, "running");
    }

    public void CompleteQueueRun(string tab, string id, string summary, string status)
    {
        var taskId = BuildQueueTaskId(tab, id);
        if (!ActiveTasks.Any(x => string.Equals(x.Id, taskId, StringComparison.OrdinalIgnoreCase)))
        {
            var title = string.IsNullOrWhiteSpace(tab) ? "queue" : $"{tab} queue";
            StartOrUpdate(taskId, "queue", title, summary, "running");
        }

        Complete(taskId, summary, status);
    }

    public TaskSummaryState GetSummary()
    {
        var active = ActiveTasks;
        return new TaskSummaryState
        {
            ActiveCount = active.Count,
            PendingPermissionCount = active.Count(task =>
                string.Equals(task.Kind, "permission", StringComparison.OrdinalIgnoreCase) ||
                string.Equals(task.Status, "waiting", StringComparison.OrdinalIgnoreCase)),
            LatestRecentTask = RecentTasks.FirstOrDefault(),
        };
    }

    public void RestoreRecentFromExecutionEvents(IEnumerable<Models.ChatExecutionEvent>? history)
    {
        var restored = new List<TaskRunStore.TaskRun>();
        var active = new Dictionary<string, TaskRunStore.TaskRun>(StringComparer.OrdinalIgnoreCase);
        var seen = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
        var normalizedHistory = NormalizeReplayHistory(history);

        if (normalizedHistory.Count > 0)
        {
            foreach (var item in normalizedHistory)
            {
                var scopedId = TryGetScopedId(item);
                if (string.IsNullOrWhiteSpace(scopedId))
                    continue;

                if (TryCreateActiveTaskFromExecutionEvent(item, out var activeTask))
                {
                    active[scopedId] = activeTask;
                    continue;
                }

                if (IsTerminalExecutionEvent(item))
                {
                    active.Remove(scopedId);
                    RemoveRunScopedActiveTasks(active, item);
                }
            }

            foreach (var item in normalizedHistory
                         .OrderByDescending(x => x.Timestamp)
                         .ThenByDescending(GetReplayPriority)
                         .ThenByDescending(x => x.Iteration)
                         .ThenByDescending(x => x.ElapsedMs))
            {
                var task = TryCreateTaskFromExecutionEvent(item);
                if (task == null || !seen.Add(task.Id))
                    continue;

                restored.Add(task);
                if (restored.Count >= 25)
                    break;
            }
        }

        _store.RestoreState(active.Values, restored);
    }

    private static int GetReplayPriority(Models.ChatExecutionEvent evt)
    {
        if (string.Equals(evt.Type, nameof(Agent.AgentEventType.Error), StringComparison.OrdinalIgnoreCase))
            return 100;
        if (string.Equals(evt.Type, nameof(Agent.AgentEventType.Complete), StringComparison.OrdinalIgnoreCase))
            return 90;
        if (string.Equals(evt.Type, nameof(Agent.AgentEventType.PermissionDenied), StringComparison.OrdinalIgnoreCase))
            return 80;
        if (string.Equals(evt.Type, nameof(Agent.AgentEventType.PermissionGranted), StringComparison.OrdinalIgnoreCase))
            return 70;
        if (string.Equals(evt.Type, nameof(Agent.AgentEventType.HookResult), StringComparison.OrdinalIgnoreCase))
            return evt.Success ? 60 : 65;
        if (string.Equals(evt.Type, nameof(Agent.AgentEventType.ToolResult), StringComparison.OrdinalIgnoreCase))
            return evt.Success ? 50 : 55;
        if (string.Equals(evt.Type, nameof(Agent.AgentEventType.ToolCall), StringComparison.OrdinalIgnoreCase))
            return 40;
        if (string.Equals(evt.Type, nameof(Agent.AgentEventType.PermissionRequest), StringComparison.OrdinalIgnoreCase))
            return 30;
        return 10;
    }

    public void ApplyAgentEvent(Agent.AgentEvent evt)
    {
        switch (evt.Type)
        {
            case Agent.AgentEventType.PermissionRequest:
                StartPermissionRequest(
                    evt.RunId,
                    evt.ToolName,
                    string.IsNullOrWhiteSpace(evt.Summary) ? "waiting for permission" : evt.Summary,
                    evt.FilePath);
                break;
            case Agent.AgentEventType.PermissionGranted:
                CompletePermissionRequest(
                    evt.RunId,
                    evt.ToolName,
                    string.IsNullOrWhiteSpace(evt.Summary) ? "permission granted" : evt.Summary,
                    true);
                break;
            case Agent.AgentEventType.PermissionDenied:
                CompletePermissionRequest(
                    evt.RunId,
                    evt.ToolName,
                    string.IsNullOrWhiteSpace(evt.Summary) ? "permission denied" : evt.Summary,
                    false);
                break;
            case Agent.AgentEventType.ToolCall:
                StartToolRun(
                    evt.RunId,
                    evt.ToolName,
                    string.IsNullOrWhiteSpace(evt.Summary) ? $"{evt.ToolName} running" : evt.Summary,
                    evt.FilePath);
                break;
            case Agent.AgentEventType.ToolResult:
                CompleteToolRun(
                    evt.RunId,
                    evt.ToolName,
                    string.IsNullOrWhiteSpace(evt.Summary) ? evt.ToolName : evt.Summary,
                    evt.Success);
                break;
            case Agent.AgentEventType.SkillCall:
                StartToolRun(
                    evt.RunId,
                    evt.ToolName,
                    string.IsNullOrWhiteSpace(evt.Summary) ? $"{evt.ToolName} running" : evt.Summary,
                    evt.FilePath,
                    skill: true);
                break;
            case Agent.AgentEventType.HookResult:
                RecordHookResult(
                    evt.RunId,
                    evt.ToolName,
                    string.IsNullOrWhiteSpace(evt.Summary) ? "hook running" : evt.Summary,
                    evt.Success,
                    evt.FilePath);
                break;
            case Agent.AgentEventType.Thinking:
            case Agent.AgentEventType.Planning:
                StartAgentRun(evt.RunId, evt.Summary);
                break;
            case Agent.AgentEventType.Paused:
                StartOrUpdate(
                    GetAgentTaskKey(evt),
                    "agent",
                    "main",
                    string.IsNullOrWhiteSpace(evt.Summary) ? "agent paused" : evt.Summary,
                    "paused",
                    evt.FilePath);
                break;
            case Agent.AgentEventType.Resumed:
                StartOrUpdate(
                    GetAgentTaskKey(evt),
                    "agent",
                    "main",
                    string.IsNullOrWhiteSpace(evt.Summary) ? "agent resumed" : evt.Summary,
                    "running",
                    evt.FilePath);
                break;
            case Agent.AgentEventType.Complete:
                CompleteAgentRun(
                    evt.RunId,
                    string.IsNullOrWhiteSpace(evt.Summary) ? "task completed" : evt.Summary,
                    true);
                CompleteByPrefix(
                    string.IsNullOrWhiteSpace(evt.RunId) ? "tool:" : $"tool:{evt.RunId}:",
                    string.IsNullOrWhiteSpace(evt.Summary) ? "task completed" : evt.Summary,
                    "completed");
                CompleteByPrefix(
                    string.IsNullOrWhiteSpace(evt.RunId) ? "permission:" : $"permission:{evt.RunId}:",
                    string.IsNullOrWhiteSpace(evt.Summary) ? "task completed" : evt.Summary,
                    "completed");
                CompleteByPrefix(
                    string.IsNullOrWhiteSpace(evt.RunId) ? "hook:" : $"hook:{evt.RunId}:",
                    string.IsNullOrWhiteSpace(evt.Summary) ? "task completed" : evt.Summary,
                    "completed");
                break;
            case Agent.AgentEventType.StopRequested:
                StartOrUpdate(
                    GetAgentTaskKey(evt),
                    "agent",
                    "main",
                    string.IsNullOrWhiteSpace(evt.Summary) ? "agent stop requested" : evt.Summary,
                    "running",
                    evt.FilePath);
                CompleteAgentRun(
                    evt.RunId,
                    string.IsNullOrWhiteSpace(evt.Summary) ? "agent stop requested" : evt.Summary,
                    false);
                CompleteByPrefix(
                    string.IsNullOrWhiteSpace(evt.RunId) ? "tool:" : $"tool:{evt.RunId}:",
                    string.IsNullOrWhiteSpace(evt.Summary) ? "agent stop requested" : evt.Summary,
                    "cancelled");
                CompleteByPrefix(
                    string.IsNullOrWhiteSpace(evt.RunId) ? "permission:" : $"permission:{evt.RunId}:",
                    string.IsNullOrWhiteSpace(evt.Summary) ? "agent stop requested" : evt.Summary,
                    "cancelled");
                CompleteByPrefix(
                    string.IsNullOrWhiteSpace(evt.RunId) ? "hook:" : $"hook:{evt.RunId}:",
                    string.IsNullOrWhiteSpace(evt.Summary) ? "agent stop requested" : evt.Summary,
                    "cancelled");
                break;
            case Agent.AgentEventType.Error:
                if (!string.IsNullOrWhiteSpace(evt.ToolName))
                {
                    CompleteToolRun(
                        evt.RunId,
                        evt.ToolName,
                        string.IsNullOrWhiteSpace(evt.Summary) ? evt.ToolName : evt.Summary,
                        false);
                }
                else
                {
                    CompleteAgentRun(
                        evt.RunId,
                        string.IsNullOrWhiteSpace(evt.Summary) ? "error occurred" : evt.Summary,
                        false);
                    CompleteByPrefix(
                        string.IsNullOrWhiteSpace(evt.RunId) ? "permission:" : $"permission:{evt.RunId}:",
                        string.IsNullOrWhiteSpace(evt.Summary) ? "error occurred" : evt.Summary,
                        "failed");
                    CompleteByPrefix(
                        string.IsNullOrWhiteSpace(evt.RunId) ? "hook:" : $"hook:{evt.RunId}:",
                        string.IsNullOrWhiteSpace(evt.Summary) ? "error occurred" : evt.Summary,
                        "failed");
                }
                break;
        }
    }

    public void ApplySubAgentStatus(Agent.SubAgentStatusEvent evt)
    {
        var taskId = string.IsNullOrWhiteSpace(evt.Id) ? "subagent:unknown" : $"subagent:{evt.Id}";
        var title = string.IsNullOrWhiteSpace(evt.Id) ? "sub-agent" : evt.Id;
        var summary = string.IsNullOrWhiteSpace(evt.Summary) ? evt.Task : evt.Summary;

        switch (evt.Status)
        {
            case Agent.SubAgentRunStatus.Started:
                StartOrUpdate(taskId, "subagent", title, summary, "running");
                StartBackgroundRun(evt.Id, title, summary);
                break;
            case Agent.SubAgentRunStatus.Completed:
                Complete(taskId, summary, "completed");
                CompleteBackgroundRun(evt.Id, title, summary, true);
                break;
            case Agent.SubAgentRunStatus.Failed:
                Complete(taskId, summary, "failed");
                CompleteBackgroundRun(evt.Id, title, summary, false);
                break;
        }
    }

    private static string GetAgentTaskKey(Agent.AgentEvent evt)
        => string.IsNullOrWhiteSpace(evt.RunId) ? "agent:main" : $"agent:{evt.RunId}";

    private static string GetToolTaskKey(Agent.AgentEvent evt)
    {
        var suffix = string.IsNullOrWhiteSpace(evt.ToolName) ? "unknown" : evt.ToolName;
        return string.IsNullOrWhiteSpace(evt.RunId)
            ? $"tool:{suffix}"
            : $"tool:{evt.RunId}:{suffix}";
    }

    private static string GetPermissionTaskKey(Agent.AgentEvent evt)
    {
        var suffix = string.IsNullOrWhiteSpace(evt.ToolName) ? "unknown" : evt.ToolName;
        return string.IsNullOrWhiteSpace(evt.RunId)
            ? $"permission:{suffix}"
            : $"permission:{evt.RunId}:{suffix}";
    }

    private static string GetHookTaskKey(Agent.AgentEvent evt)
    {
        var suffix = string.IsNullOrWhiteSpace(evt.ToolName) ? "unknown" : evt.ToolName;
        return string.IsNullOrWhiteSpace(evt.RunId)
            ? $"hook:{suffix}"
            : $"hook:{evt.RunId}:{suffix}";
    }

    private static string BuildBackgroundTaskId(string id)
        => string.IsNullOrWhiteSpace(id) ? "background:unknown" : $"background:{id}";

    private static string BuildQueueTaskId(string tab, string id)
    {
        var scope = string.IsNullOrWhiteSpace(tab) ? "default" : tab;
        var suffix = string.IsNullOrWhiteSpace(id) ? "unknown" : id;
        return $"queue:{scope}:{suffix}";
    }

    private static TaskRunStore.TaskRun? TryCreateTaskFromExecutionEvent(Models.ChatExecutionEvent item)
    {
        static string BuildScopedId(string prefix, Models.ChatExecutionEvent evt)
        {
            var suffix = string.IsNullOrWhiteSpace(evt.ToolName) ? "main" : evt.ToolName;
            return string.IsNullOrWhiteSpace(evt.RunId)
                ? $"{prefix}:{suffix}"
                : $"{prefix}:{evt.RunId}:{suffix}";
        }

        if (string.Equals(item.Type, nameof(Agent.AgentEventType.PermissionGranted), StringComparison.OrdinalIgnoreCase) ||
            string.Equals(item.Type, nameof(Agent.AgentEventType.PermissionDenied), StringComparison.OrdinalIgnoreCase))
        {
            return new TaskRunStore.TaskRun
            {
                Id = BuildScopedId("permission", item),
                Kind = "permission",
                Title = string.IsNullOrWhiteSpace(item.ToolName) ? "permission" : $"{item.ToolName} permission",
                Summary = item.Summary,
                Status = string.Equals(item.Type, nameof(Agent.AgentEventType.PermissionDenied), StringComparison.OrdinalIgnoreCase) ? "failed" : "completed",
                StartedAt = item.Timestamp,
                UpdatedAt = item.Timestamp,
                FilePath = item.FilePath,
            };
        }

        if (string.Equals(item.Type, nameof(Agent.AgentEventType.ToolResult), StringComparison.OrdinalIgnoreCase))
        {
            return new TaskRunStore.TaskRun
            {
                Id = BuildScopedId("tool", item),
                Kind = "tool",
                Title = string.IsNullOrWhiteSpace(item.ToolName) ? "tool" : item.ToolName,
                Summary = item.Summary,
                Status = item.Success ? "completed" : "failed",
                StartedAt = item.Timestamp,
                UpdatedAt = item.Timestamp,
                FilePath = item.FilePath,
            };
        }

        if (string.Equals(item.Type, nameof(Agent.AgentEventType.HookResult), StringComparison.OrdinalIgnoreCase))
        {
            return new TaskRunStore.TaskRun
            {
                Id = BuildScopedId("hook", item),
                Kind = "hook",
                Title = string.IsNullOrWhiteSpace(item.ToolName) ? "hook" : $"{item.ToolName} hook",
                Summary = item.Summary,
                Status = item.Success ? "completed" : "failed",
                StartedAt = item.Timestamp,
                UpdatedAt = item.Timestamp,
                FilePath = item.FilePath,
            };
        }

        if (string.Equals(item.Type, nameof(Agent.AgentEventType.Complete), StringComparison.OrdinalIgnoreCase) ||
            string.Equals(item.Type, nameof(Agent.AgentEventType.Error), StringComparison.OrdinalIgnoreCase) ||
            string.Equals(item.Type, nameof(Agent.AgentEventType.StopRequested), StringComparison.OrdinalIgnoreCase))
        {
            return new TaskRunStore.TaskRun
            {
                Id = BuildScopedId("agent", item),
                Kind = "agent",
                Title = "main",
                Summary = item.Summary,
                Status = string.Equals(item.Type, nameof(Agent.AgentEventType.Error), StringComparison.OrdinalIgnoreCase)
                    ? "failed"
                    : string.Equals(item.Type, nameof(Agent.AgentEventType.StopRequested), StringComparison.OrdinalIgnoreCase)
                        ? "cancelled"
                        : "completed",
                StartedAt = item.Timestamp,
                UpdatedAt = item.Timestamp,
                FilePath = item.FilePath,
            };
        }

        return null;
    }

    private static bool TryCreateActiveTaskFromExecutionEvent(
        Models.ChatExecutionEvent item,
        out TaskRunStore.TaskRun task)
    {
        task = new TaskRunStore.TaskRun();

        if (string.Equals(item.Type, nameof(Agent.AgentEventType.PermissionRequest), StringComparison.OrdinalIgnoreCase))
        {
            task = new TaskRunStore.TaskRun
            {
                Id = BuildScopedId("permission", item),
                Kind = "permission",
                Title = string.IsNullOrWhiteSpace(item.ToolName) ? "permission request" : $"{item.ToolName} permission",
                Summary = item.Summary,
                Status = "waiting",
                StartedAt = item.Timestamp,
                UpdatedAt = item.Timestamp,
                FilePath = item.FilePath,
            };
            return true;
        }

        if (string.Equals(item.Type, nameof(Agent.AgentEventType.ToolCall), StringComparison.OrdinalIgnoreCase))
        {
            task = new TaskRunStore.TaskRun
            {
                Id = BuildScopedId("tool", item),
                Kind = "tool",
                Title = string.IsNullOrWhiteSpace(item.ToolName) ? "tool" : item.ToolName,
                Summary = item.Summary,
                Status = "running",
                StartedAt = item.Timestamp,
                UpdatedAt = item.Timestamp,
                FilePath = item.FilePath,
            };
            return true;
        }

        if (string.Equals(item.Type, nameof(Agent.AgentEventType.SkillCall), StringComparison.OrdinalIgnoreCase))
        {
            task = new TaskRunStore.TaskRun
            {
                Id = BuildScopedId("tool", item),
                Kind = "skill",
                Title = string.IsNullOrWhiteSpace(item.ToolName) ? "skill" : item.ToolName,
                Summary = item.Summary,
                Status = "running",
                StartedAt = item.Timestamp,
                UpdatedAt = item.Timestamp,
                FilePath = item.FilePath,
            };
            return true;
        }

        if (string.Equals(item.Type, nameof(Agent.AgentEventType.Paused), StringComparison.OrdinalIgnoreCase) ||
            string.Equals(item.Type, nameof(Agent.AgentEventType.Resumed), StringComparison.OrdinalIgnoreCase))
        {
            task = new TaskRunStore.TaskRun
            {
                Id = BuildScopedId("agent", item),
                Kind = "agent",
                Title = "main",
                Summary = item.Summary,
                Status = string.Equals(item.Type, nameof(Agent.AgentEventType.Paused), StringComparison.OrdinalIgnoreCase)
                    ? "paused"
                    : "running",
                StartedAt = item.Timestamp,
                UpdatedAt = item.Timestamp,
                FilePath = item.FilePath,
            };
            return true;
        }

        if (string.Equals(item.Type, nameof(Agent.AgentEventType.Thinking), StringComparison.OrdinalIgnoreCase) ||
            string.Equals(item.Type, nameof(Agent.AgentEventType.Planning), StringComparison.OrdinalIgnoreCase))
        {
            task = new TaskRunStore.TaskRun
            {
                Id = BuildScopedId("agent", item),
                Kind = "agent",
                Title = "main",
                Summary = item.Summary,
                Status = "running",
                StartedAt = item.Timestamp,
                UpdatedAt = item.Timestamp,
                FilePath = item.FilePath,
            };
            return true;
        }

        return false;
    }

    private static bool IsTerminalExecutionEvent(Models.ChatExecutionEvent item)
    {
        if (string.Equals(item.Type, nameof(Agent.AgentEventType.PermissionGranted), StringComparison.OrdinalIgnoreCase) ||
            string.Equals(item.Type, nameof(Agent.AgentEventType.PermissionDenied), StringComparison.OrdinalIgnoreCase))
            return true;

        if (string.Equals(item.Type, nameof(Agent.AgentEventType.ToolResult), StringComparison.OrdinalIgnoreCase))
            return true;

        if (string.Equals(item.Type, nameof(Agent.AgentEventType.Complete), StringComparison.OrdinalIgnoreCase))
            return true;

        if (string.Equals(item.Type, nameof(Agent.AgentEventType.Error), StringComparison.OrdinalIgnoreCase))
            return true;

        if (string.Equals(item.Type, nameof(Agent.AgentEventType.StopRequested), StringComparison.OrdinalIgnoreCase))
            return true;

        return false;
    }

    private static void RemoveRunScopedActiveTasks(
        Dictionary<string, TaskRunStore.TaskRun> active,
        Models.ChatExecutionEvent item)
    {
        if (string.IsNullOrWhiteSpace(item.RunId))
            return;

        var shouldClearAllByRun =
            string.Equals(item.Type, nameof(Agent.AgentEventType.Complete), StringComparison.OrdinalIgnoreCase) ||
            string.Equals(item.Type, nameof(Agent.AgentEventType.StopRequested), StringComparison.OrdinalIgnoreCase) ||
            (string.Equals(item.Type, nameof(Agent.AgentEventType.Error), StringComparison.OrdinalIgnoreCase)
             && string.IsNullOrWhiteSpace(item.ToolName));

        if (!shouldClearAllByRun)
            return;

        var prefixes = new[]
        {
            $"agent:{item.RunId}:",
            $"tool:{item.RunId}:",
            $"permission:{item.RunId}:",
            $"hook:{item.RunId}:",
        };

        var keys = active.Keys
            .Where(key => prefixes.Any(prefix => key.StartsWith(prefix, StringComparison.OrdinalIgnoreCase)))
            .ToList();

        foreach (var key in keys)
            active.Remove(key);
    }

    private static string? TryGetScopedId(Models.ChatExecutionEvent item)
    {
        if (string.Equals(item.Type, nameof(Agent.AgentEventType.PermissionRequest), StringComparison.OrdinalIgnoreCase) ||
            string.Equals(item.Type, nameof(Agent.AgentEventType.PermissionGranted), StringComparison.OrdinalIgnoreCase) ||
            string.Equals(item.Type, nameof(Agent.AgentEventType.PermissionDenied), StringComparison.OrdinalIgnoreCase))
            return BuildScopedId("permission", item);

        if (string.Equals(item.Type, nameof(Agent.AgentEventType.ToolCall), StringComparison.OrdinalIgnoreCase) ||
            string.Equals(item.Type, nameof(Agent.AgentEventType.SkillCall), StringComparison.OrdinalIgnoreCase) ||
            string.Equals(item.Type, nameof(Agent.AgentEventType.ToolResult), StringComparison.OrdinalIgnoreCase))
            return BuildScopedId("tool", item);

        if (string.Equals(item.Type, nameof(Agent.AgentEventType.Thinking), StringComparison.OrdinalIgnoreCase) ||
            string.Equals(item.Type, nameof(Agent.AgentEventType.Planning), StringComparison.OrdinalIgnoreCase) ||
            string.Equals(item.Type, nameof(Agent.AgentEventType.Paused), StringComparison.OrdinalIgnoreCase) ||
            string.Equals(item.Type, nameof(Agent.AgentEventType.Resumed), StringComparison.OrdinalIgnoreCase) ||
            string.Equals(item.Type, nameof(Agent.AgentEventType.StopRequested), StringComparison.OrdinalIgnoreCase) ||
            string.Equals(item.Type, nameof(Agent.AgentEventType.Complete), StringComparison.OrdinalIgnoreCase))
            return BuildScopedId("agent", item);

        if (string.Equals(item.Type, nameof(Agent.AgentEventType.Error), StringComparison.OrdinalIgnoreCase))
        {
            if (string.IsNullOrWhiteSpace(item.ToolName))
                return BuildScopedId("agent", item);
            return BuildScopedId("tool", item);
        }

        return null;
    }

    private static string BuildScopedId(string prefix, Models.ChatExecutionEvent evt)
    {
        var suffix = string.IsNullOrWhiteSpace(evt.ToolName) ? "main" : evt.ToolName;
        return string.IsNullOrWhiteSpace(evt.RunId)
            ? $"{prefix}:{suffix}"
            : $"{prefix}:{evt.RunId}:{suffix}";
    }

    private static IReadOnlyList<Models.ChatExecutionEvent> NormalizeReplayHistory(
        IEnumerable<Models.ChatExecutionEvent>? history)
    {
        if (history == null)
            return Array.Empty<Models.ChatExecutionEvent>();

        var ordered = history
            .Where(x => x != null)
            .OrderBy(x => x.Timestamp == default ? DateTime.MinValue : x.Timestamp)
            .ThenBy(x => x.Iteration)
            .ThenBy(x => x.ElapsedMs)
            .ToList();

        var result = new List<Models.ChatExecutionEvent>(ordered.Count);
        foreach (var item in ordered)
        {
            if (result.Count == 0)
            {
                result.Add(item);
                continue;
            }

            var last = result[^1];
            if (!IsNearDuplicateReplayEvent(last, item))
            {
                result.Add(item);
                continue;
            }

            last.Timestamp = item.Timestamp;
            last.ElapsedMs = Math.Max(last.ElapsedMs, item.ElapsedMs);
            last.InputTokens = Math.Max(last.InputTokens, item.InputTokens);
            last.OutputTokens = Math.Max(last.OutputTokens, item.OutputTokens);
            last.StepCurrent = Math.Max(last.StepCurrent, item.StepCurrent);
            last.StepTotal = Math.Max(last.StepTotal, item.StepTotal);
            last.Iteration = Math.Max(last.Iteration, item.Iteration);
            if (string.IsNullOrWhiteSpace(last.FilePath))
                last.FilePath = item.FilePath;
            if (!string.IsNullOrWhiteSpace(item.Summary) && item.Summary.Length >= (last.Summary?.Length ?? 0))
                last.Summary = item.Summary;
            if (item.Steps is { Count: > 0 })
                last.Steps = item.Steps.ToList();
            if (!string.IsNullOrWhiteSpace(item.ToolInput))
                last.ToolInput = item.ToolInput;
            last.Success = last.Success && item.Success;
        }

        return result;
    }

    private static bool IsNearDuplicateReplayEvent(Models.ChatExecutionEvent left, Models.ChatExecutionEvent right)
    {
        if (!string.Equals(left.RunId, right.RunId, StringComparison.OrdinalIgnoreCase))
            return false;
        if (!string.Equals(left.Type, right.Type, StringComparison.OrdinalIgnoreCase))
            return false;
        if (!string.Equals(left.ToolName, right.ToolName, StringComparison.OrdinalIgnoreCase))
            return false;
        if (!string.Equals(left.Summary?.Trim(), right.Summary?.Trim(), StringComparison.Ordinal))
            return false;
        if (!string.Equals(left.FilePath ?? "", right.FilePath ?? "", StringComparison.OrdinalIgnoreCase))
            return false;
        if (left.Success != right.Success)
            return false;

        var delta = (right.Timestamp - left.Timestamp).Duration();
        return delta <= TimeSpan.FromSeconds(2);
    }
}