using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.RazorPages;
using Microsoft.EntityFrameworkCore;
using _2021_backend.Data;
using _2021_backend.Models;

namespace _2021_backend.Pages.Students
{
    public class DeleteModel : PageModel
    {
        private readonly _2021_backend.Data.BackendContext Context;

        public DeleteModel(_2021_backend.Data.BackendContext context)
        {
            Context = context;
        }

        [BindProperty]
        public Student Student { get; set; }

        public async Task<IActionResult> OnGetAsync(string? idstr)
        {
            if (idstr == null)
            {
                return NotFound();
            }
            Guid id = Guid.Parse(idstr);

            Student = await Context.Students.FirstOrDefaultAsync(m => m.Guid == id);

            if (Student == null)
            {
                return NotFound();
            }
            return Page();
        }

        public async Task<IActionResult> OnPostAsync(string? idstr)
        {
            if (idstr == null)
            {
                return NotFound();
            }
            Guid id = Guid.Parse(idstr);

            Student = await Context.Students.FindAsync(id);

            if (Student != null)
            {
                var q = from e in Context.Sessions where e.Students.Contains(id) select e;
                var lst = q.ToList();
                foreach(var it in lst)
                {
                    it.Students.RemoveAll(k => k == id);
                }
                Context.Students.Remove(Student);
                Context.SaveChanges();
            }

            return RedirectToPage("./Index");
        }
    }
}