using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Mvc;
using LittleShop.Services;
using LittleShop.DTOs;

namespace LittleShop.Areas.Admin.Controllers;

[Area("Admin")]
[Authorize(Policy = "AdminOnly")]
public class UsersController : Controller
{
    private readonly IAuthService _authService;

    public UsersController(IAuthService authService)
    {
        _authService = authService;
    }

    public async Task<IActionResult> Index()
    {
        var users = await _authService.GetAllUsersAsync();
        return View(users);
    }

    public IActionResult Create()
    {
        return View();
    }

    [HttpPost]
    [ValidateAntiForgeryToken]
    public async Task<IActionResult> Create(CreateUserDto model)
    {
        try
        {
            if (!ModelState.IsValid)
            {
                return View(model);
            }

            var user = await _authService.CreateUserAsync(model);
            if (user == null)
            {
                ModelState.AddModelError("Username", "User with this username already exists");
                return View(model);
            }

            TempData["SuccessMessage"] = $"User '{user.Username}' created successfully";
            return RedirectToAction(nameof(Index));
        }
        catch (Exception ex)
        {
            ModelState.AddModelError("", "An error occurred while creating the user: " + ex.Message);
            return View(model);
        }
    }

    public async Task<IActionResult> Edit(Guid id)
    {
        var user = await _authService.GetUserByIdAsync(id);
        if (user == null)
        {
            return NotFound();
        }

        var model = new UpdateUserDto
        {
            Username = user.Username,
            IsActive = user.IsActive
        };

        ViewData["UserId"] = id;
        return View(model);
    }

    [HttpPost]
    [ValidateAntiForgeryToken]
    public async Task<IActionResult> Edit(Guid id, UpdateUserDto model)
    {
        try
        {
            // Additional validation for required username
            if (string.IsNullOrWhiteSpace(model.Username))
            {
                ModelState.AddModelError("Username", "Username is required");
            }

            // Validate password if provided
            if (!string.IsNullOrEmpty(model.Password) && model.Password.Length < 8)
            {
                ModelState.AddModelError("Password", "Password must be at least 8 characters if changing");
            }

            if (!ModelState.IsValid)
            {
                ViewData["UserId"] = id;
                return View(model);
            }

            var success = await _authService.UpdateUserAsync(id, model);
            if (!success)
            {
                // Check if it's because of duplicate username
                var existingUser = await _authService.GetUserByIdAsync(id);
                if (existingUser == null)
                {
                    return NotFound();
                }
                
                ModelState.AddModelError("Username", "Username is already taken by another user");
                ViewData["UserId"] = id;
                return View(model);
            }

            TempData["SuccessMessage"] = "User updated successfully";
            return RedirectToAction(nameof(Index));
        }
        catch (Exception ex)
        {
            ModelState.AddModelError("", "An error occurred while updating the user: " + ex.Message);
            ViewData["UserId"] = id;
            return View(model);
        }
    }

    [HttpPost]
    [ValidateAntiForgeryToken]
    public async Task<IActionResult> Delete(Guid id)
    {
        try
        {
            // Prevent admin user from deleting themselves
            var currentUserIdClaim = User.FindFirst(System.Security.Claims.ClaimTypes.NameIdentifier)?.Value;
            if (Guid.TryParse(currentUserIdClaim, out Guid currentUserId) && currentUserId == id)
            {
                TempData["ErrorMessage"] = "You cannot delete your own account";
                return RedirectToAction(nameof(Index));
            }

            // Get user info for confirmation message
            var user = await _authService.GetUserByIdAsync(id);
            if (user == null)
            {
                TempData["ErrorMessage"] = "User not found";
                return RedirectToAction(nameof(Index));
            }

            var success = await _authService.DeleteUserAsync(id);
            if (success)
            {
                TempData["SuccessMessage"] = $"User '{user.Username}' has been deactivated";
            }
            else
            {
                TempData["ErrorMessage"] = "Failed to delete user";
            }

            return RedirectToAction(nameof(Index));
        }
        catch (Exception ex)
        {
            TempData["ErrorMessage"] = "An error occurred while deleting the user: " + ex.Message;
            return RedirectToAction(nameof(Index));
        }
    }
}