using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Mvc;
using Microsoft.EntityFrameworkCore;
using OnProfNext.Server.Data;
using OnProfNext.Shared.Models;
using OnProfNext.Shared.Models.DTOs;

namespace OnProfNext.Server.Controllers
{
    [Route("api/[controller]")]
    [ApiController]
    [Authorize]
    public class OrdersController : ControllerBase
    {
        private readonly AppDbContext _context;

        public OrdersController(AppDbContext context)
        {
            _context = context;
        }

        [HttpGet("byproject/{projectId}")]
        public async Task<ActionResult<IEnumerable<OrderDto>>> GetOrdersByProject(int projectId)
        {
            var orders = await _context.Orders
                .Include(o => o.OrderUsers)
                    .ThenInclude(ou => ou.User)
                .Where(o => o.ProjectId == projectId)
                .AsNoTracking()
                .Select(o => new OrderDto
                {
                    Id = o.Id,
                    ProjectId = o.ProjectId,
                    Auftragsnummer = o.Auftragsnummer,
                    Titel = o.Titel,
                    Status = o.Status,
                    Planstunden = o.Planstunden,
                    Iststunden = o.Iststunden,
                    MandantId = o.MandantId,
                    Mitarbeiter = o.OrderUsers
                        .Select(ou => new UserDto
                        {
                            Id = ou.User!.Id,
                            Username = ou.User.Username,
                            FirstName = ou.User.FirstName,
                            LastName = ou.User.LastName,
                            Email = ou.User.Email
                        }).ToList()
                })
                .ToListAsync();

            return Ok(orders);
        }

        // GET: api/orders/5
        [HttpGet("{id}")]
        public async Task<ActionResult<OrderDto>> GetOrder(int id)
        {
            var order = await _context.Orders
                .Include(o => o.OrderUsers)
                    .ThenInclude(ou => ou.User)
                .AsNoTracking()
                .FirstOrDefaultAsync(o => o.Id == id);

            if (order == null)
                return NotFound();

            var dto = new OrderDto
            {
                Id = order.Id,
                ProjectId = order.ProjectId,
                Auftragsnummer = order.Auftragsnummer,
                Titel = order.Titel,
                Status = order.Status,
                Planstunden = order.Planstunden,
                Iststunden = order.Iststunden,
                Projektcode = order.Projektcode,
                MandantId = order.MandantId,
                CreatedAt = order.CreatedAt,
                UpdatedAt = order.UpdatedAt,
                Mitarbeiter = order.OrderUsers
                    .Select(ou => new UserDto
                    {
                        Id = ou.User!.Id,
                        Username = ou.User.Username,
                        FirstName = ou.User.FirstName,
                        LastName = ou.User.LastName,
                        Email = ou.User.Email
                    }).ToList()
            };

            return Ok(dto);
        }

        // POST: api/orders
        [HttpPost]
        public async Task<ActionResult<OrderDto>> CreateOrder(OrderCreateDto dto)
        {
            var order = new Order
            {
                ProjectId = dto.ProjectId,
                Auftragsnummer = dto.Auftragsnummer,
                Titel = dto.Titel,
                Status = dto.Status,
                Planstunden = dto.Planstunden,
                Iststunden = 0,
                MandantId = dto.MandantId,
                CreatedAt = DateTime.UtcNow,
                UpdatedAt = DateTime.UtcNow
            };

            _context.Orders.Add(order);
            await _context.SaveChangesAsync();

            // Mitarbeiter zuordnen
            if (dto.UserIds != null && dto.UserIds.Any())
            {
                var relations = dto.UserIds.Select(uid => new OrderUser
                {
                    OrderId = order.Id,
                    UserId = uid
                });

                _context.OrderUsers.AddRange(relations);
                await _context.SaveChangesAsync();
            }

            // Antwort zusammenbauen
            var createdDto = new OrderDto
            {
                Id = order.Id,
                ProjectId = order.ProjectId,
                Auftragsnummer = order.Auftragsnummer,
                Titel = order.Titel,
                Status = order.Status,
                Planstunden = order.Planstunden,
                Iststunden = order.Iststunden,
                MandantId = order.MandantId,
                CreatedAt = order.CreatedAt,
                UpdatedAt = order.UpdatedAt
            };

            return CreatedAtAction(nameof(GetOrder), new { id = order.Id }, createdDto);
        }

        //PUT: api/orders/5
        [HttpPut("{id}")]
        public async Task<IActionResult> UpdateOrder(int id, OrderDto dto)
        {
            var order = await _context.Orders.FindAsync(id);
            if (order == null) return NotFound();

            order.Titel = dto.Titel;
            order.Status = dto.Status;
            order.Planstunden = dto.Planstunden;
            order.Iststunden = dto.Iststunden;
            order.Projektcode = dto.Projektcode;
            order.UpdatedAt = DateTime.UtcNow;

            await _context.SaveChangesAsync();
            return NoContent();
        }

        // DELETE: api/orders/5
        [HttpDelete("{id}")]
        public async Task<IActionResult> DeleteOrder(int id)
        {
            var order = await _context.Orders
                .Include(o => o.OrderUsers)
                .FirstOrDefaultAsync(o => o.Id == id);

            if (order == null)
                return NotFound();

            _context.OrderUsers.RemoveRange(order.OrderUsers);
            _context.Orders.Remove(order);
            await _context.SaveChangesAsync();

            return NoContent();
        }

        private int GetCurrentUserId()
        {
            var userIdClaim = User.FindFirst("UserId")?.Value;
            if (string.IsNullOrEmpty(userIdClaim))
                throw new UnauthorizedAccessException("Kein User-Claim im Token gefunden.");

            return int.Parse(userIdClaim);
        }

        [HttpGet("mine")]
        public async Task<ActionResult<IEnumerable<OrderDto>>> GetMyOrders()
        {
            var userId = GetCurrentUserId();

            var orders = await _context.Orders
                .Include(o => o.OrderUsers)
                    .ThenInclude(ou => ou.User)
                .Where(o => o.OrderUsers.Any(ou => ou.UserId == userId))
                .AsNoTracking()
                .Select(o => new OrderDto
                {
                    Id = o.Id,
                    ProjectId = o.ProjectId,
                    Auftragsnummer = o.Auftragsnummer,
                    Titel = o.Titel,
                    Status = o.Status,
                    Planstunden = o.Planstunden,
                    Iststunden = o.Iststunden,
                    Projektcode = o.Projektcode,
                    MandantId = o.MandantId,
                    CreatedAt = o.CreatedAt,
                    UpdatedAt = o.UpdatedAt,
                    Mitarbeiter = o.OrderUsers
                        .Select(ou => new UserDto
                        {
                            Id = ou.User!.Id,
                            Username = ou.User.Username,
                            FirstName = ou.User.FirstName,
                            LastName = ou.User.LastName,
                            Email = ou.User.Email
                        }).ToList()
                })
                .ToListAsync();

            return Ok(orders);
        }
    }
}