using System;
using System.Collections.Generic;
using System.Data;
using System.Linq;
using BathHouseManagmet.Database;
using BathHouseManagmet.Models;
using CommunityToolkit.Mvvm.ComponentModel;
using CommunityToolkit.Mvvm.Input;
using Microsoft.Extensions.DependencyInjection;

namespace BathHouseManagmet.ViewModels;

public partial class DiscountViewModel : ViewModelBase
{
    private readonly IServiceProvider _serviceProvider;

    [ObservableProperty] List<Discount> _discounts;
    [ObservableProperty] int _currentPageSize;
    [ObservableProperty] List<int> _pageSizes;
    [ObservableProperty] string _pageInfo;

    private int totalPages;
    private int currentPage = 0;

    public DiscountViewModel(IServiceProvider serviceProvider)
    {
        _serviceProvider = serviceProvider;

        using (var rep = serviceProvider.GetRequiredService<DiscountRepository>())
            Discounts = new List<Discount>(rep.GetPage());

        PageSizes = new List<int>([5, 10, 15]);
        CurrentPageSize = PageSizes.First();
    }

    partial void OnCurrentPageSizeChanged(int value)
    {
        CalculatePage();
    }

    void CalculatePage()
    {
        using var db = new DiscountRepository();
        var rowsCount = db.GetRowsCount();
        totalPages = (int)Math.Ceiling(((double)rowsCount / CurrentPageSize));
        ShowFirstPage();
    }

    void ShowPage(int pageIndex)
    {
        currentPage = pageIndex;
        using var db = new DiscountRepository();
        Discounts.Clear();
        var rows = db.GetPage(pageIndex, CurrentPageSize);
        rows.ForEach(d => Discounts.Add(d));
        PageInfo = $"Страница {currentPage + 1} из {totalPages}";
    }

    [RelayCommand]
    private void ShowFirstPage()
    {
        ShowPage(0);
    }

    [RelayCommand]
    private void ShowLastPage()
    {
        ShowPage(totalPages - 1);
    }

    [RelayCommand]
    private void ShowNextPage()
    {
        if (currentPage < totalPages - 1)
            ShowPage(currentPage + 1);
    }

    [RelayCommand]
    private void ShowPreviousPage()
    {
        if (currentPage > 0)
            ShowPage(currentPage - 1);
    }
}