using Microsoft.EntityFrameworkCore;
using vendorApproverBackend.Data;
using vendorApproverBackend.Entities;
using vendorApproverBackend.Requests;
using vendorApproverBackend.Exceptions;

namespace vendorApproverBackend.Services
{
    public class CertificationPackService
    {
        private readonly DataContext _context;

        public CertificationPackService(DataContext context)
        {
            _context = context;
        }

     
        public async Task<CertificationPack> AddPackAsync(AddCertificationPackRequest request)
        {
            var pack = new CertificationPack
            {
                Name = request.Name,
                Description = request.Description,
                Timestamp = DateTime.UtcNow 
            };

            if (request.Price.HasValue)
            {
                pack.Price = request.Price.Value;
            }
            _context.CertificationPacks.Add(pack);
            await _context.SaveChangesAsync();
            return pack;
        }

        public async Task<CertificationPack> GetPackByIdAsync(long id)
        {
            var pack = await _context.CertificationPacks.FindAsync(id);

            if (pack == null)
            {
                throw new NotFoundException($"Certification Pack with ID {id} not found.");
            }

            return pack;
        }


        public async Task<List<CertificationPack>> GetAllPacksAsync()
        {
            return await _context.CertificationPacks
                .OrderByDescending(p => p.Timestamp)
                .ToListAsync();
        }

        public async Task<CertificationPack> UpdatePackAsync(long id, UpdateCertificationPackRequest request)
        {
            var pack = await GetPackByIdAsync(id);
            if (request.Name != null)
            {
                pack.Name = request.Name;
            }
            if (request.Description != null)
            {
                pack.Description = request.Description;
            }
            if (request.Price.HasValue)
            {
                pack.Price = request.Price.Value;
            }
            _context.CertificationPacks.Update(pack);
            await _context.SaveChangesAsync();
            return pack;
        }

        public async Task DeletePackAsync(long id)
        {
            var pack = await GetPackByIdAsync(id);

            _context.CertificationPacks.Remove(pack);
            await _context.SaveChangesAsync();
        }
    }
}