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

namespace MoneyMap.Pages
{
    public class AccountDetailsModel : PageModel
    {
        private readonly MoneyMapContext _db;

        public AccountDetailsModel(MoneyMapContext db)
        {
            _db = db;
        }

        public Account Account { get; set; } = null!;
        public List<CardWithStats> Cards { get; set; } = new();
        public int TransactionCount { get; set; }

        [TempData]
        public string? SuccessMessage { get; set; }

        [TempData]
        public string? ErrorMessage { get; set; }

        public async Task<IActionResult> OnGetAsync(int id)
        {
            var account = await _db.Accounts.FindAsync(id);
            if (account == null)
                return NotFound();

            Account = account;

            // Get cards linked to this account
            var cards = await _db.Cards
                .Where(c => c.AccountId == id)
                .OrderBy(c => c.Owner)
                .ThenBy(c => c.Last4)
                .ToListAsync();

            var cardStats = new List<CardWithStats>();
            foreach (var card in cards)
            {
                var transactionCount = await _db.Transactions.CountAsync(t => t.CardId == card.Id);
                cardStats.Add(new CardWithStats
                {
                    Card = card,
                    TransactionCount = transactionCount
                });
            }

            Cards = cardStats;

            // Get transaction count for this account
            TransactionCount = await _db.Transactions.CountAsync(t => t.AccountId == id);

            return Page();
        }

        public async Task<IActionResult> OnPostDeleteCardAsync(int cardId)
        {
            var card = await _db.Cards.FindAsync(cardId);
            if (card == null)
            {
                ErrorMessage = "Card not found.";
                return RedirectToPage(new { id = card?.AccountId });
            }

            var accountId = card.AccountId;

            var transactionCount = await _db.Transactions.CountAsync(t => t.CardId == card.Id);
            if (transactionCount > 0)
            {
                ErrorMessage = $"Cannot delete card. It has {transactionCount} transaction(s) associated with it.";
                return RedirectToPage(new { id = accountId });
            }

            _db.Cards.Remove(card);
            await _db.SaveChangesAsync();

            SuccessMessage = "Card deleted successfully.";
            return RedirectToPage(new { id = accountId });
        }

        public class CardWithStats
        {
            public Card Card { get; set; } = null!;
            public int TransactionCount { get; set; }
        }
    }
}