using Microsoft.Win32;
using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Data.Entity;
using System.Data.Entity.Infrastructure;
using System.Data.Entity.Migrations;
using System.Data.SqlClient;
using System.Data.SqlTypes;
using System.Linq;
using System.Runtime.Remoting.Contexts;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using System.IO;
using System.Data.Entity.Validation;
using System.Data.OleDb;
using System.Data;
using System.Reflection;

namespace musicschoolapp.Pages
{
    /// <summary>
    /// Логика взаимодействия для StudentEditingPage.xaml
    /// </summary>
    public partial class EnrollmentEditingPage : Page
    {
        musicschoolEntities1 mse = new musicschoolEntities1();
        DbSet<Enrollment> dbContext_;
        bool isadmin_;
        List<Enrollment> students1;
        bool adding = false;
        public EnrollmentEditingPage(bool isadmin)
        {
            InitializeComponent();
            this.isadmin_ = isadmin;
            if(isadmin)
            {
                dGridStudent.IsReadOnly = false;
            }
            else
            {
                isadmin_ = false;
               dGridStudent.IsReadOnly = true;
            }
            combobox_courses.ItemsSource = mse.Course.ToList();
            students1 = mse.Enrollment.ToList();
            dGridStudent.ItemsSource = students1;
        }


        public int updateDB()
        {
            combobox_courses.SelectedIndex = -1;
            try
            {
                foreach (var student in students1)
                {
                    var original = mse.Enrollment.Find(student.EnrollmentID);

                    if (original != null)
                    {
                        mse.Entry(original).CurrentValues.SetValues(student);
                    }
                    else
                    {
                        mse.Enrollment.Add(student);
                    }
                }

                int saveresult = mse.SaveChanges();
                students1 = mse.Enrollment.ToList();
                dGridStudent.ItemsSource = students1;
                return saveresult;
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.InnerException.ToString());
                return -1;
            }
        }
        private void dGridStudent_MouseDoubleClick(object sender, MouseButtonEventArgs e)
        {
            var grid = (DataGrid)sender;
            var cellInfo = grid.SelectedCells[grid.CurrentCell.Column.DisplayIndex];

            if (cellInfo.Column.Header.ToString() == "Фото")
            {
                if (MessageBox.Show("Вы дважды кликнули по столбцу 'Фото'. Изменить?", "Вопрос", MessageBoxButton.YesNo) == MessageBoxResult.Yes)
                {
                    OpenFileDialog openFileDialog = new OpenFileDialog();
                    openFileDialog.ShowDialog();
                    if (mse.Student.Find((grid.SelectedItem as Enrollment).EnrollmentID) == null)
                    {
                        MessageBox.Show("Объект не создан.");
                        grid.SelectedItem = -1;
                        mse.Enrollment.Add(dGridStudent.SelectedItem as Enrollment);
                        try
                        {
                            mse.SaveChanges();
                        }
                        catch (DbEntityValidationException ex)
                        {
                            foreach (var entityValidationErrors in ex.EntityValidationErrors)
                            {
                                foreach (var validationError in entityValidationErrors.ValidationErrors)
                                {
                                    MessageBox.Show("Свойство: " + validationError.PropertyName + " Ошибка: " + validationError.ErrorMessage);
                                }
                            }
                        }

                        MessageBox.Show("добавил");
                        int index = grid.SelectedIndex;
                        grid.SelectedIndex = -1;
                        grid.SelectedIndex = index;
                        dGridStudent_SelectionChanged(sender, new SelectionChangedEventArgs(DataGrid.SelectionChangedEvent, new Collection<object> { }, new Collection<object> { dGridStudent.SelectedItem }));
                    }
                    mse.SaveChanges();
                    dGridStudent.ItemsSource = mse.Enrollment.ToList();
                }
            }
        }
        private void dGridStudent_SelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            if (e.AddedItems != null && e.AddedItems.Count > 0)
            {
               

            }
            else if (e.RemovedItems != null && e.RemovedItems.Count > 0)
            {
                Enrollment selectedStudent = (e.RemovedItems[0] as Enrollment);
                if (selectedStudent != null)
                {
                    Enrollment studentInDb = mse.Enrollment.Find(selectedStudent.EnrollmentID);
                    if (studentInDb != null && (e.RemovedItems[0] as Enrollment).Student != null && (e.RemovedItems[0] as Enrollment).Course != null && isadmin_)
                    {
                        
                        if (MessageBox.Show("Удалить " + (e.RemovedItems[0] as Enrollment).Student.LastName + " (" + (e.RemovedItems[0] as Enrollment).Course.Name + ")", "Внимание",MessageBoxButton.YesNo) == MessageBoxResult.Yes)
                        {
                            mse.Enrollment.Remove(studentInDb);
                            try
                            {
                                mse.SaveChanges();
                            }
                            catch (DbUpdateException ex)
                            {

                                MessageBox.Show("Запись, похоже, удалить нельзя.\n\n" + ex.InnerException);
                                MessageBox.Show("запись была удалена только из таблицы, но сохранена в базе данных, перезапустите окно и продолжайте работать.");
                                return;
                            }
                            students1.Remove(dGridStudent.SelectedItem as Enrollment);
                            dGridStudent.SelectedIndex = -1;
                            if ((e.RemovedItems[0] as Enrollment).Student != null)
                            {
                                MessageBox.Show("Удалено: " + (e.RemovedItems[0] as Enrollment).Student.LastName);
                            }
                            else
                            {
                                MessageBox.Show("Удалена 1 запись.");
                            }
                        }
                    }
                }
            }

        }

        private void BtnEdit_Click(object sender, RoutedEventArgs e)
        {
            
            {

            }
        }
        private void ToExcelButton_OnClick(object sender, RoutedEventArgs e)
        {
            var d = dGridStudent.ItemsSource.Cast<Enrollment>();
            var data = ToDataTable(d.ToList());
            var dialog = new SaveFileDialog();
            dialog.DefaultExt = ".xlsx";
            dialog.Filter = "Excel файл |*.xlsx";
            dialog.ShowDialog();
            if (dialog.FileName != String.Empty)
            {
                ToExcelFile(data, dialog.FileName);
            }
        }

        public static DataTable ToDataTable<T>(List<T> items)
        {
            var dataTable = new DataTable(typeof(T).Name);

            var properties = typeof(T).GetProperties(BindingFlags.Public | BindingFlags.Instance);
            foreach (var prop in properties)
            {
                var type = (prop.PropertyType.IsGenericType && prop.PropertyType.GetGenericTypeDefinition() == typeof(Nullable<>) ? Nullable.GetUnderlyingType(prop.PropertyType) : prop.PropertyType);
                dataTable.Columns.Add(prop.Name, type);
            }
            foreach (var item in items)
            {
                var values = new object[properties.Length];
                for (var i = 0; i < properties.Length; i++)
                {
                    values[i] = properties[i].GetValue(item, null);
                }
                dataTable.Rows.Add(values);
            }
            return dataTable;
        }

        public static void ToExcelFile(DataTable dataTable, string filePath, bool overwriteFile = true)
        {
            if (File.Exists(filePath) && overwriteFile)
                File.Delete(filePath);

            using (var connection = new OleDbConnection())
            {
                connection.ConnectionString = $"Provider=Microsoft.ACE.OLEDB.12.0;Data Source={filePath};" +
                                              "Extended Properties='Excel 12.0 Xml;HDR=YES;'";
                connection.Open();
                using (var command = new OleDbCommand())
                {
                    command.Connection = connection;
                    var columnNames = (from DataColumn dataColumn in dataTable.Columns select dataColumn.ColumnName).ToList();
                    var tableName = !string.IsNullOrWhiteSpace(dataTable.TableName) ? dataTable.TableName : Guid.NewGuid().ToString();
                    command.CommandText = $"CREATE TABLE [{tableName}] ({string.Join(",", columnNames.Select(c => $"[{c}] VARCHAR").ToArray())});";
                    command.ExecuteNonQuery();
                    foreach (DataRow row in dataTable.Rows)
                    {
                        var rowValues = (from DataColumn column in dataTable.Columns select (row[column] != null && row[column] != DBNull.Value) ? row[column].ToString() : string.Empty).ToList();
                        command.CommandText = $"INSERT INTO [{tableName}]({string.Join(",", columnNames.Select(c => $"[{c}]"))}) VALUES ({string.Join(",", rowValues.Select(r => $"'{r}'").ToArray())});";
                        command.ExecuteNonQuery();
                    }
                }

                connection.Close();
            }
            MessageBox.Show("Файл успешно сохранён в "+filePath);
        }
        private void Button_Click(object sender, RoutedEventArgs e)
        {

        }

        private void combobox_courses_SelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            dGridStudent.SelectedIndex = 0;
            
            if (combobox_courses.SelectedItem != null)
            {
                dGridStudent.ItemsSource = students1.Where(x => x.CourseID == (combobox_courses.SelectedItem as Course).CourseID).ToList();
            }
            else
            {
                dGridStudent.ItemsSource = students1;
            }
        }

        private void TextBox_TextChanged(object sender, TextChangedEventArgs e)
        {
            dGridStudent.SelectedIndex = -1;
            if (textbox_search.Text != String.Empty && dGridStudent.SelectedItem == null)
            {
                if(combobox_courses.SelectedItem != null)
                {
                    dGridStudent.ItemsSource = students1.Where(x => x.Student.LastName.Contains(textbox_search.Text) && x.Course == combobox_courses.SelectedItem as Course).ToList();
                }
                else 
                dGridStudent.ItemsSource = students1.Where(x => x.Student.LastName.Contains(textbox_search.Text)).ToList();
            }
            else
            {
                dGridStudent.ItemsSource = students1;
            }
        }
      
    }
}