using API.Data;
using API.Models;
using API.Services;
using Microsoft.EntityFrameworkCore;
using Model;

namespace API.GraphQL;

public class Query
{
    private static string EnsureAuthenticated(IHttpContextAccessor? httpContextAccessor, ITokenService tokenService)
    {
        var httpContext = httpContextAccessor?.HttpContext;
        if (httpContext == null)
            throw new Exception("Authentication required. Please provide a valid authorization token.");

        var authHeader = httpContext.Request.Headers["Authorization"].FirstOrDefault();
        if (string.IsNullOrWhiteSpace(authHeader))
            throw new Exception("Authentication required. Please login to access this resource.");

        var token = authHeader.StartsWith("Bearer ", StringComparison.OrdinalIgnoreCase)
            ? authHeader["Bearer ".Length..].Trim()
            : authHeader.Trim();

        var username = tokenService.ValidateToken(token);
        if (string.IsNullOrEmpty(username))
            throw new Exception("Invalid or expired authentication token. Please login again.");

        return username;
    }

    public async Task<CardNote?> GetNote(
        [Service] AppDbContext db,
        [Service] IHttpContextAccessor httpContextAccessor,
        [Service] ITokenService tokenService,
        string cardName)
    {
        var username = EnsureAuthenticated(httpContextAccessor, tokenService);
        try
        {
            var note = await db.CardNotes.FirstOrDefaultAsync(n => n.CardName == cardName && n.Username == username);
            return note ?? new CardNote { Username = username, CardName = cardName, Note = "" };
        }
        catch (Exception ex)
        {
            Console.WriteLine($"[WARNING] Could not retrieve note: {ex.Message}");
            return new CardNote { Username = username, CardName = cardName, Note = "" };
        }
    }

    public async Task<List<CardNote>> GetNotes(
        [Service] AppDbContext db,
        [Service] IHttpContextAccessor httpContextAccessor,
        [Service] ITokenService tokenService)
    {
        var username = EnsureAuthenticated(httpContextAccessor, tokenService);
        try
        {
            return await db.CardNotes.Where(n => n.Username == username).ToListAsync();
        }
        catch (Exception ex)
        {
            Console.WriteLine($"[WARNING] Could not retrieve notes: {ex.Message}");
            return new List<CardNote>();
        }
    }

    public async Task<List<UserDeck>> GetDecks(
        [Service] AppDbContext db,
        [Service] IHttpContextAccessor httpContextAccessor,
        [Service] ITokenService tokenService)
    {
        EnsureAuthenticated(httpContextAccessor, tokenService);
        try
        {
            return await db.UserDecks.OrderByDescending(d => d.UpdatedAt).ToListAsync();
        }
        catch (Exception ex)
        {
            Console.WriteLine($"[WARNING] Could not retrieve decks: {ex.Message}");
            return new List<UserDeck>();
        }
    }

    public async Task<UserDeck?> GetDeck(
        [Service] AppDbContext db,
        [Service] IHttpContextAccessor httpContextAccessor,
        [Service] ITokenService tokenService,
        Guid id)
    {
        EnsureAuthenticated(httpContextAccessor, tokenService);
        try
        {
            return await db.UserDecks.FindAsync(id);
        }
        catch (Exception ex)
        {
            Console.WriteLine($"[WARNING] Could not retrieve deck: {ex.Message}");
            return null;
        }
    }
}