using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Authorization;
using Microsoft.EntityFrameworkCore;
using LingAdmin.IdentityService.Data;
using LingAdmin.IdentityService.Services;
using LingAdmin.Shared.DTOs;

namespace LingAdmin.IdentityService.Controllers;

/// <summary>
/// 用户管理控制器 - 管理员操作
/// </summary>
[ApiController]
[Route("api/[controller]")]
[Authorize(Roles = "Admin,SuperAdmin")]
public class UsersController : ControllerBase
{
    private readonly IdentityDbContext _context;
    private readonly IPasswordHasher _passwordHasher;
    private readonly ILogger<UsersController> _logger;

    public UsersController(
        IdentityDbContext context,
        IPasswordHasher passwordHasher,
        ILogger<UsersController> logger)
    {
        _context = context;
        _passwordHasher = passwordHasher;
        _logger = logger;
    }

    /// <summary>
    /// 获取用户列表（分页）
    /// </summary>
    [HttpGet]
    public async Task<ActionResult<ApiResponse<PaginatedResponse<UserDto>>>> GetUsers(
        [FromQuery] PaginationRequest pagination)
    {
        var query = _context.Users.AsQueryable();

        // Search
        if (!string.IsNullOrWhiteSpace(pagination.Search))
        {
            var search = pagination.Search.ToLower();
            query = query.Where(u => 
                u.Name.ToLower().Contains(search) || 
                u.Email.ToLower().Contains(search));
        }

        // Sort
        query = pagination.SortBy?.ToLower() switch
        {
            "name" => pagination.SortDescending ? query.OrderByDescending(u => u.Name) : query.OrderBy(u => u.Name),
            "email" => pagination.SortDescending ? query.OrderByDescending(u => u.Email) : query.OrderBy(u => u.Email),
            "createdat" => pagination.SortDescending ? query.OrderByDescending(u => u.CreatedAt) : query.OrderBy(u => u.CreatedAt),
            _ => query.OrderByDescending(u => u.CreatedAt)
        };

        var totalCount = await query.CountAsync();

        var users = await query
            .Skip((pagination.Page - 1) * pagination.PageSize)
            .Take(pagination.PageSize)
            .Select(u => new UserDto
            {
                Id = u.Id,
                Name = u.Name,
                Email = u.Email,
                Status = u.Status,
                CreatedAt = u.CreatedAt,
                LastLoginAt = u.LastLoginAt
            })
            .ToListAsync();

        var response = new PaginatedResponse<UserDto>
        {
            Items = users,
            TotalCount = totalCount,
            Page = pagination.Page,
            PageSize = pagination.PageSize
        };

        return Ok(ApiResponse<PaginatedResponse<UserDto>>.Ok(response));
    }

    /// <summary>
    /// 获取单个用户
    /// </summary>
    [HttpGet("{id}")]
    public async Task<ActionResult<ApiResponse<UserDto>>> GetUser(int id)
    {
        var user = await _context.Users.FindAsync(id);

        if (user == null)
        {
            return NotFound(ApiResponse<UserDto>.NotFound("User not found"));
        }

        var userDto = new UserDto
        {
            Id = user.Id,
            Name = user.Name,
            Email = user.Email,
            Status = user.Status,
            CreatedAt = user.CreatedAt,
            LastLoginAt = user.LastLoginAt
        };

        return Ok(ApiResponse<UserDto>.Ok(userDto));
    }

    /// <summary>
    /// 更新用户状态
    /// </summary>
    [HttpPatch("{id}/status")]
    public async Task<ActionResult<ApiResponse<UserDto>>> UpdateUserStatus(int id, [FromBody] UpdateStatusRequest request)
    {
        var user = await _context.Users.FindAsync(id);

        if (user == null)
        {
            return NotFound(ApiResponse<UserDto>.NotFound("User not found"));
        }

        if (!new[] { "Active", "Inactive", "Suspended" }.Contains(request.Status))
        {
            return BadRequest(ApiResponse<UserDto>.Error("Invalid status. Must be Active, Inactive, or Suspended"));
        }

        user.Status = request.Status;
        user.UpdatedAt = DateTime.UtcNow;
        await _context.SaveChangesAsync();

        var userDto = new UserDto
        {
            Id = user.Id,
            Name = user.Name,
            Email = user.Email,
            Status = user.Status,
            CreatedAt = user.CreatedAt,
            LastLoginAt = user.LastLoginAt
        };

        return Ok(ApiResponse<UserDto>.Ok(userDto, "User status updated"));
    }

    /// <summary>
    /// 重置用户密码（管理员操作）
    /// </summary>
    [HttpPost("{id}/reset-password")]
    public async Task<ActionResult<ApiResponse<object>>> ResetUserPassword(int id, [FromBody] AdminResetPasswordRequest request)
    {
        var user = await _context.Users.FindAsync(id);

        if (user == null)
        {
            return NotFound(ApiResponse<object>.NotFound("User not found"));
        }

        user.PasswordHash = _passwordHasher.HashPassword(request.NewPassword);
        user.UpdatedAt = DateTime.UtcNow;

        // Revoke all refresh tokens
        var tokens = await _context.RefreshTokens
            .Where(rt => rt.UserId == id && rt.RevokedAt == null)
            .ToListAsync();

        foreach (var token in tokens)
        {
            token.RevokedAt = DateTime.UtcNow;
        }

        await _context.SaveChangesAsync();

        _logger.LogInformation("Admin reset password for user {UserId}", id);

        return Ok(ApiResponse<object>.Ok(new { }, "Password reset successfully"));
    }

    /// <summary>
    /// 删除用户
    /// </summary>
    [HttpDelete("{id}")]
    [Authorize(Roles = "SuperAdmin")]
    public async Task<ActionResult<ApiResponse<object>>> DeleteUser(int id)
    {
        var user = await _context.Users.FindAsync(id);

        if (user == null)
        {
            return NotFound(ApiResponse<object>.NotFound("User not found"));
        }

        // Delete all refresh tokens
        var tokens = await _context.RefreshTokens.Where(rt => rt.UserId == id).ToListAsync();
        _context.RefreshTokens.RemoveRange(tokens);

        _context.Users.Remove(user);
        await _context.SaveChangesAsync();

        _logger.LogInformation("User {UserId} deleted", id);

        return Ok(ApiResponse<object>.Ok(new { }, "User deleted successfully"));
    }

    /// <summary>
    /// [开发用] 重置用户密码 - 仅在开发环境可用
    /// </summary>
    [HttpPost("{id}/dev-reset-password")]
    [AllowAnonymous]
    public async Task<ActionResult<ApiResponse<object>>> DevResetPassword(int id, [FromBody] AdminResetPasswordRequest request)
    {
        // Only allow in development
        var env = HttpContext.RequestServices.GetService<IWebHostEnvironment>();
        if (!env!.IsDevelopment())
        {
            return NotFound();
        }

        var user = await _context.Users.FindAsync(id);
        if (user == null)
        {
            return NotFound(ApiResponse<object>.NotFound("User not found"));
        }

        user.PasswordHash = _passwordHasher.HashPassword(request.NewPassword);
        user.UpdatedAt = DateTime.UtcNow;
        await _context.SaveChangesAsync();

        return Ok(ApiResponse<object>.Ok(new { hash = user.PasswordHash }, "Password reset successfully"));
    }
}

public class UpdateStatusRequest
{
    public required string Status { get; set; }
}

public class AdminResetPasswordRequest
{
    public required string NewPassword { get; set; }
}