using System;
using System.Linq;
using Microsoft.Maui.Controls;
using System.Collections.Generic;
using System.Formats.Tar;

namespace MauiApp1
{
    public partial class MainPage : ContentPage
    {
        private DatabaseService _db = new DatabaseService();
        private Book _selectedBook;

        public MainPage()
        {
            InitializeComponent();
        }

        protected override async void OnAppearing()
        {
            base.OnAppearing();
            await LoadBooks();
        }

        private async Task LoadBooks()
        {
            var books = await _db.GetBooksAsync();
            BooksList.ItemsSource = books;
        }

        private async void OnSaveClicked(object sender, EventArgs e)
        {
            string title = TitleEntry.Text?.Trim();
            string author = AuthorEntry.Text?.Trim();
            int.TryParse(YearEntry.Text, out int year);

            if (string.IsNullOrWhiteSpace(title))
            {
                await DisplayAlert("Błąd", "Podaj tytuł książki.", "OK");
                return;
            }

            if (_selectedBook == null)
            {
                var newBook = new Book { Title = title, Author = author, Year = year };
                await _db.AddBookAsync(newBook);
            }
            else
            {
                _selectedBook.Title = title;
                _selectedBook.Author = author;
                _selectedBook.Year = year;
                await _db.UpdateBookAsync(_selectedBook);
                _selectedBook = null;
            }

            await LoadBooks();
            ClearForm();
        }

        private void OnClearClicked(object sender, EventArgs e)
        {
            _selectedBook = null;
            ClearForm();
        }

        private void ClearForm()
        {
            TitleEntry.Text = "";
            AuthorEntry.Text = "";
            YearEntry.Text = "";
        }

        private void BooksList_SelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            _selectedBook = e.CurrentSelection.FirstOrDefault() as Book;
            if (_selectedBook != null)
            {
                TitleEntry.Text = _selectedBook.Title;
                AuthorEntry.Text = _selectedBook.Author;
                YearEntry.Text = _selectedBook.Year.ToString();
            }
        }

        private async void OnDeleteClicked(object sender, EventArgs e)
        {
            var button = sender as Button;
            var book = button?.CommandParameter as Book;
            if (book == null) return;

            bool confirm = await DisplayAlert("Potwierdzenie", $"Usunąć książkę '{book.Title}'?", "Tak", "Nie");
            if (confirm)
            {
                await _db.DeleteBookAsync(book);
                await LoadBooks();
            }
        }
    }
}