// File: Services/Scanners/ThreadScanner.cs

using System.Diagnostics;
using WebmrAPI.Models;
using WebmrAPI.Utils;

namespace WebmrAPI.Services.Scanners
{
    public class ThreadScanner : AbstractCpuScanner<ProcessThreadInfo>
    {
        override public ScanTarget Target { get => ScanTarget.Threads; }
        internal int PID { get; private set; }

        override internal async Task<bool> ScanAsync(Dictionary<long, ProcessThreadInfo> data)
        {
            return await Task.Run(() =>
            {
                try
                {
                    using (var process = Process.GetProcessById(PID))
                    foreach (ProcessThread thread in process.Threads)
                    {
                        ProcessThreadInfo info;

                        if (GetFromCacheOrNew(thread.Id, out info))
                        {
                            info.CpuUsage = CalcCpuUsage(info.ProcessorTime, Container.Elapsed.TotalMilliseconds);
                        }
                        else
                        {
                            info.ID = thread.Id;
                            info.CpuUsage = 0;
                        }

                        info.BasePriority = thread.BasePriority;
                        info.CurrentPriority = thread.CurrentPriority;
                        info.TotalProcessorTime = thread.TotalProcessorTime;

                        data.Add(info.ID, info);
                    }
                    return true;
                }
                catch (System.ComponentModel.Win32Exception ex) when (ex.NativeErrorCode == 5)
                {
                    Provider.Logger.LogWarning($"Access denied to process {PID} for thread scanning. Error: {ex.Message}");
                }
                catch (InvalidOperationException ex)
                {
                    Provider.Logger.LogWarning($"Process {PID} might have exited during thread enumeration. Error: {ex.Message}");
                }
                catch (Exception ex)
                {
                    Provider.Logger.LogError($"An unexpected error occurred while scanning threads for PID {PID}. Error: {ex.Message}");
                }
                return false;
            });
        }

        public ThreadScanner(IScanProvider scanner, LazyConcurrentContainer<ProcessThreadInfo> container, int pid)
            : base(scanner, container) 
        { 
            PID = pid;
        }
    }
}