using System;
using System.Collections.ObjectModel;
using System.ComponentModel;
using System.Globalization;
using System.IO;
using System.Linq;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Input;
using Microsoft.Win32;

namespace Compdfkit_Tools.PDFControl
{
    public partial class FileGridListControl : UserControl, INotifyPropertyChanged
    {
        public class FileInfoData
        {
            public string FileName { get; set; }
            public string Size { get; set; }
            public string Location { get; set; }
        };

        private int _fileNum;
        public int FileNum
        {
            set
            {
                _fileNum = value;
                OnPropertyChanged("FileNum");
                OnPropertyChanged("FileNumText");
                FileNumChanged?.Invoke(this, EventArgs.Empty);
            }
            get => _fileNum;
        }

        public string FileNumText => $"Total {FileNum} Files";

        public event PropertyChangedEventHandler PropertyChanged;
        public event EventHandler FileNumChanged;
        public ObservableCollection<FileInfoData> FileInfoDataList = new ObservableCollection<FileInfoData>();
        
        
        public FileGridListControl()
        {
            InitializeComponent();
            DataContext = this;
            FileInfoDataList.CollectionChanged += (sender, args) =>
            {
                FileNum = FileInfoDataList.Count;
            };
            FileDataGrid.ItemsSource = FileInfoDataList;
        }
        
        private void AddFiles_Click(object sender, RoutedEventArgs e)
        {
            var dialog = new OpenFileDialog();
            dialog.Multiselect = true;
            dialog.Filter = @"PDF Files (*.pdf)|*.pdf";
            dialog.ShowDialog();
            dialog.Multiselect = true;

            foreach (var fileName in dialog.FileNames)
            {
                var file = new FileInfo(fileName);
                var fileInfoData = new FileInfoData()
                {
                    FileName = file.Name,
                    Size = GetSizeFromBytes(file.Length),
                    Location = file.FullName
                };
                
                if (FileInfoDataList.All(item => item.Location != fileInfoData.Location))
                {
                    FileInfoDataList.Add(fileInfoData);
                }
            }

            OnPropertyChanged("FileNum");
        }

        
        private string GetSizeFromBytes(long bytes)
        {
            string[] sizes = { "B", "KB", "MB", "GB", "TB" };
            double len = bytes;
            int order = 0;
            while (len >= 1024 && order < sizes.Length - 1)
            {
                order++;
                len /= 1024;
            }
            return $"{len:0.##} {sizes[order]}";
        }

        private void Remove_Click(object sender, RoutedEventArgs e)
        {
            if (FileDataGrid.SelectedItems.Count == 0)
            {
                FileInfoDataList.Clear();
                OnPropertyChanged("FileNum");
                return;
            }
            var selectedItems = FileDataGrid.SelectedItems;
            var selectedItemsList = selectedItems.Cast<FileInfoData>().ToList();
            
            foreach (var item in selectedItemsList)
            {
                FileInfoDataList.Remove(item);
            }
            OnPropertyChanged("FileNum");
        }
        
        protected virtual void OnPropertyChanged(string propertyName = null)
        {
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
        }

        private void FileDataGrid_SelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            BtnRemove.Content = FileDataGrid.SelectedItems.Count > 0 ? "Remove" : "Remove All";
        }

        private void FileDataGrid_OnMouseLeftButtonUp(object sender, MouseButtonEventArgs e)
        {
            if (e.OriginalSource.GetType() != typeof(DataGridCell))
            {
                FileDataGrid.UnselectAll();
            }
        }
    }
}