using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Windows.Input;
using Microsoft.Win32;
using leak_test_project.Models;
using leak_test_project.Utils;
using leak_test_project.ViewModels.Core;

namespace leak_test_project.ViewModels
{
    /// <summary>
    /// Data 화면의 검색/CSV 내보내기 로직을 담당하는 ViewModel.
    /// </summary>
    public class DataViewModel : ObservableObject
    {
        private DateTime _startDate = DateTime.Now.AddDays(-7);
        public DateTime StartDate { get => _startDate; set => SetProperty(ref _startDate, value); }

        private DateTime _endDate = DateTime.Now;
        public DateTime EndDate { get => _endDate; set => SetProperty(ref _endDate, value); }

        private int _judgmentIndex = 0;
        public int JudgmentIndex { get => _judgmentIndex; set => SetProperty(ref _judgmentIndex, value); }

        private string _idFilter = "";
        public string IdFilter { get => _idFilter; set => SetProperty(ref _idFilter, value); }

        private string _operatorFilter = "";
        public string OperatorFilter { get => _operatorFilter; set => SetProperty(ref _operatorFilter, value); }

        private string _lotNoFilter = "";
        public string LotNoFilter { get => _lotNoFilter; set => SetProperty(ref _lotNoFilter, value); }

        private string _modelFilter = "";
        public string ModelFilter { get => _modelFilter; set => SetProperty(ref _modelFilter, value); }

        private List<InspectData> _searchResults = new List<InspectData>();
        public List<InspectData> SearchResults { get => _searchResults; set => SetProperty(ref _searchResults, value); }

        // UI 표출용 (데이터가 없어도 격자를 그리기 위해 빈 행을 추가한 리스트)
        private List<InspectData> _displayResults = new List<InspectData>();
        public List<InspectData> DisplayResults { get => _displayResults; set => SetProperty(ref _displayResults, value); }

        private int _resultCount = 0;
        public int ResultCount { get => _resultCount; set => SetProperty(ref _resultCount, value); }

        private bool _isBusy = false;
        public bool IsBusy { get => _isBusy; set => SetProperty(ref _isBusy, value); }

        private readonly IDialogService _dialogService;
        private System.Threading.CancellationTokenSource _cts;

        public ICommand SearchCommand { get; }
        public ICommand CancelCommand { get; }

        /// <summary> Close 버튼 시 홈으로 돌아가는 커맨드 </summary>
        public ICommand CloseCommand { get; }

        public DataViewModel(Action navigateHome, IDialogService dialogService = null)
        {
            _dialogService = dialogService ?? new DefaultDialogService();
            SearchCommand = new RelayCommand(o => ExecuteSearch());
            CancelCommand = new RelayCommand(o => ExecuteCancel());
            CloseCommand = new RelayCommand(o => navigateHome?.Invoke());

            // 화면 초기 진입 시 빈 격자가 보이도록 빈 리스트로 초기 렌더링
            UpdateDisplayResults(new List<InspectData>());
        }

        private void UpdateDisplayResults(List<InspectData> results)
        {
            var display = new List<InspectData>(results);

            // 화면을 가득 채울 수 있도록 최소 50개의 행을 보장 (Excel 스타일)
            const int MinDisplayRows = 50;
            while (display.Count < MinDisplayRows)
            {
                display.Add(new InspectData());
            }

            DisplayResults = display;
        }

        private void ExecuteCancel()
        {
            _cts?.Cancel();
        }

        private async void ExecuteSearch()
        {
            _cts?.Cancel();
            _cts?.Dispose();
            _cts = new System.Threading.CancellationTokenSource();
            var token = _cts.Token;

            IsBusy = true;
            try
            {
                string[] judgmentOptions = { "[전체]", "OK", "NG" };
                string judgment = JudgmentIndex >= 0 && JudgmentIndex < judgmentOptions.Length 
                    ? judgmentOptions[JudgmentIndex] 
                    : "[전체]";

                var results = await System.Threading.Tasks.Task.Run(() => 
                    LogParser.ParseLogs(
                        StartDate, 
                        EndDate, 
                        judgment, 
                        IdFilter?.Trim() ?? "",
                        OperatorFilter?.Trim() ?? "",
                        LotNoFilter?.Trim() ?? "",
                        ModelFilter?.Trim() ?? "",
                        token
                    ),
                    token
                );
                SearchResults = results;
                ResultCount = results.Count;

                UpdateDisplayResults(results);

                if (results.Count == 0)
                {
                    _dialogService.ShowWarning("해당 조건의 데이터가 없습니다.");
                }
            }
            catch (OperationCanceledException)
            {
                _dialogService.ShowMessage("조회가 취소되었습니다.");
                CloseCommand.Execute(null);
            }
            catch (Exception ex)
            {
                _dialogService.ShowWarning($"조회 중 오류 발생: {ex.Message}");
            }
            finally
            {
                IsBusy = false;
            }
        }
    }
}