package handler

import (
	"fmt"
	"strconv"

	"github.com/gin-gonic/gin"

	"carrot_bbs/internal/dto"
	"carrot_bbs/internal/pkg/response"
	"carrot_bbs/internal/service"
)

// UserHandler 用户处理器
type UserHandler struct {
	userService *service.UserService
	jwtService  *service.JWTService
}

// NewUserHandler 创建用户处理器
func NewUserHandler(userService *service.UserService) *UserHandler {
	return &UserHandler{
		userService: userService,
	}
}

// Register 用户注册
func (h *UserHandler) Register(c *gin.Context) {
	type RegisterRequest struct {
		Username         string `json:"username" binding:"required"`
		Email            string `json:"email" binding:"required,email"`
		Password         string `json:"password" binding:"required,min=6"`
		Nickname         string `json:"nickname" binding:"required"`
		Phone            string `json:"phone"`
		VerificationCode string `json:"verification_code" binding:"required"`
	}

	var req RegisterRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		response.BadRequest(c, err.Error())
		return
	}

	user, err := h.userService.Register(c.Request.Context(), req.Username, req.Email, req.Password, req.Nickname, req.Phone, req.VerificationCode)
	if err != nil {
		if se, ok := err.(*service.ServiceError); ok {
			response.Error(c, se.Code, se.Message)
			return
		}
		response.InternalServerError(c, "failed to register")
		return
	}

	// 生成Token
	accessToken, _ := h.jwtService.GenerateAccessToken(user.ID, user.Username)
	refreshToken, _ := h.jwtService.GenerateRefreshToken(user.ID, user.Username)

	response.Success(c, gin.H{
		"user":          dto.ConvertUserToResponse(user),
		"token":         accessToken,
		"refresh_token": refreshToken,
	})
}

// Login 用户登录
func (h *UserHandler) Login(c *gin.Context) {
	type LoginRequest struct {
		Username string `json:"username"`
		Account  string `json:"account"`
		Password string `json:"password" binding:"required"`
	}

	var req LoginRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		response.BadRequest(c, err.Error())
		return
	}

	account := req.Account
	if account == "" {
		account = req.Username
	}
	if account == "" {
		response.BadRequest(c, "username or account is required")
		return
	}

	user, err := h.userService.Login(c.Request.Context(), account, req.Password)
	if err != nil {
		if se, ok := err.(*service.ServiceError); ok {
			response.Error(c, se.Code, se.Message)
			return
		}
		response.InternalServerError(c, "failed to login")
		return
	}

	// 生成Token
	accessToken, _ := h.jwtService.GenerateAccessToken(user.ID, user.Username)
	refreshToken, _ := h.jwtService.GenerateRefreshToken(user.ID, user.Username)

	response.Success(c, gin.H{
		"user":          dto.ConvertUserToResponse(user),
		"token":         accessToken,
		"refresh_token": refreshToken,
	})
}

// SendRegisterCode 发送注册验证码
func (h *UserHandler) SendRegisterCode(c *gin.Context) {
	type SendCodeRequest struct {
		Email string `json:"email" binding:"required,email"`
	}

	var req SendCodeRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		response.BadRequest(c, err.Error())
		return
	}

	if err := h.userService.SendRegisterCode(c.Request.Context(), req.Email); err != nil {
		if se, ok := err.(*service.ServiceError); ok {
			response.Error(c, se.Code, se.Message)
			return
		}
		response.InternalServerError(c, "failed to send register verification code")
		return
	}

	response.Success(c, gin.H{"success": true})
}

// SendPasswordResetCode 发送找回密码验证码
func (h *UserHandler) SendPasswordResetCode(c *gin.Context) {
	type SendCodeRequest struct {
		Email string `json:"email" binding:"required,email"`
	}

	var req SendCodeRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		response.BadRequest(c, err.Error())
		return
	}

	if err := h.userService.SendPasswordResetCode(c.Request.Context(), req.Email); err != nil {
		if se, ok := err.(*service.ServiceError); ok {
			response.Error(c, se.Code, se.Message)
			return
		}
		response.InternalServerError(c, "failed to send reset verification code")
		return
	}

	response.Success(c, gin.H{"success": true})
}

// ResetPassword 找回密码并重置
func (h *UserHandler) ResetPassword(c *gin.Context) {
	type ResetPasswordRequest struct {
		Email            string `json:"email" binding:"required,email"`
		VerificationCode string `json:"verification_code" binding:"required"`
		NewPassword      string `json:"new_password" binding:"required,min=6"`
	}

	var req ResetPasswordRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		response.BadRequest(c, err.Error())
		return
	}

	if err := h.userService.ResetPasswordByEmail(c.Request.Context(), req.Email, req.VerificationCode, req.NewPassword); err != nil {
		if se, ok := err.(*service.ServiceError); ok {
			response.Error(c, se.Code, se.Message)
			return
		}
		response.InternalServerError(c, "failed to reset password")
		return
	}

	response.Success(c, gin.H{"success": true})
}

// GetCurrentUser 获取当前用户
func (h *UserHandler) GetCurrentUser(c *gin.Context) {
	userID := c.GetString("user_id")
	if userID == "" {
		response.Unauthorized(c, "")
		return
	}

	user, err := h.userService.GetUserByID(c.Request.Context(), userID)
	if err != nil {
		response.NotFound(c, "user not found")
		return
	}

	// 实时计算帖子数量
	postsCount, err := h.userService.GetUserPostCount(c.Request.Context(), userID)
	if err != nil {
		// 如果获取失败，使用数据库中的值
		postsCount = int64(user.PostsCount)
	}

	response.Success(c, dto.ConvertUserToDetailResponseWithPostsCount(user, int(postsCount)))
}

// GetUserByID 获取指定用户
func (h *UserHandler) GetUserByID(c *gin.Context) {
	id := c.Param("id")
	currentUserID := c.GetString("user_id")

	// 获取用户信息，包含双向关注状态
	user, isFollowing, isFollowingMe, err := h.userService.GetUserByIDWithMutualFollowStatus(c.Request.Context(), id, currentUserID)
	if err != nil {
		response.NotFound(c, "user not found")
		return
	}

	// 实时计算帖子数量
	postsCount, err := h.userService.GetUserPostCount(c.Request.Context(), id)
	if err != nil {
		// 如果获取失败，使用数据库中的值
		postsCount = int64(user.PostsCount)
	}

	// 转换为响应格式，包含双向关注状态和实时计算的帖子数量
	userResponse := dto.ConvertUserToResponseWithMutualFollowAndPostsCount(user, isFollowing, isFollowingMe, int(postsCount))

	response.Success(c, userResponse)
}

// UpdateUser 更新用户
func (h *UserHandler) UpdateUser(c *gin.Context) {
	userID := c.GetString("user_id")
	if userID == "" {
		response.Unauthorized(c, "")
		return
	}

	type UpdateRequest struct {
		Nickname string  `json:"nickname"`
		Bio      string  `json:"bio"`
		Website  string  `json:"website"`
		Location string  `json:"location"`
		Avatar   string  `json:"avatar"`
		Phone    *string `json:"phone"`
		Email    *string `json:"email"`
	}

	var req UpdateRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		response.BadRequest(c, err.Error())
		return
	}

	user, err := h.userService.GetUserByID(c.Request.Context(), userID)
	if err != nil {
		response.NotFound(c, "user not found")
		return
	}

	if req.Nickname != "" {
		user.Nickname = req.Nickname
	}
	if req.Bio != "" {
		user.Bio = req.Bio
	}
	if req.Website != "" {
		user.Website = req.Website
	}
	if req.Location != "" {
		user.Location = req.Location
	}
	if req.Avatar != "" {
		user.Avatar = req.Avatar
	}
	if req.Phone != nil {
		user.Phone = req.Phone
	}
	if req.Email != nil {
		if user.Email == nil || *user.Email != *req.Email {
			user.EmailVerified = false
		}
		user.Email = req.Email
	}

	err = h.userService.UpdateUser(c.Request.Context(), user)
	if err != nil {
		response.InternalServerError(c, "failed to update user")
		return
	}

	// 实时计算帖子数量
	postsCount, err := h.userService.GetUserPostCount(c.Request.Context(), userID)
	if err != nil {
		// 如果获取失败，使用数据库中的值
		postsCount = int64(user.PostsCount)
	}

	response.Success(c, dto.ConvertUserToDetailResponseWithPostsCount(user, int(postsCount)))
}

// SendEmailVerifyCode 发送当前用户邮箱验证码
func (h *UserHandler) SendEmailVerifyCode(c *gin.Context) {
	userID := c.GetString("user_id")
	if userID == "" {
		response.Unauthorized(c, "")
		return
	}

	type SendCodeRequest struct {
		Email string `json:"email" binding:"required,email"`
	}
	var req SendCodeRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		response.BadRequest(c, err.Error())
		return
	}

	if err := h.userService.SendCurrentUserEmailVerifyCode(c.Request.Context(), userID, req.Email); err != nil {
		if se, ok := err.(*service.ServiceError); ok {
			response.Error(c, se.Code, se.Message)
			return
		}
		response.InternalServerError(c, "failed to send email verify code")
		return
	}

	response.Success(c, gin.H{"success": true})
}

// VerifyEmail 验证当前用户邮箱
func (h *UserHandler) VerifyEmail(c *gin.Context) {
	userID := c.GetString("user_id")
	if userID == "" {
		response.Unauthorized(c, "")
		return
	}

	type VerifyEmailRequest struct {
		Email            string `json:"email" binding:"required,email"`
		VerificationCode string `json:"verification_code" binding:"required"`
	}
	var req VerifyEmailRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		response.BadRequest(c, err.Error())
		return
	}

	if err := h.userService.VerifyCurrentUserEmail(c.Request.Context(), userID, req.Email, req.VerificationCode); err != nil {
		if se, ok := err.(*service.ServiceError); ok {
			response.Error(c, se.Code, se.Message)
			return
		}
		response.InternalServerError(c, "failed to verify email")
		return
	}

	response.Success(c, gin.H{"success": true})
}

// RefreshToken 刷新Token
func (h *UserHandler) RefreshToken(c *gin.Context) {
	type RefreshRequest struct {
		RefreshToken string `json:"refresh_token" binding:"required"`
	}

	var req RefreshRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		response.BadRequest(c, err.Error())
		return
	}

	// 解析 refresh token
	claims, err := h.jwtService.ParseToken(req.RefreshToken)
	if err != nil {
		response.Unauthorized(c, "invalid refresh token")
		return
	}

	// 生成新 token
	accessToken, _ := h.jwtService.GenerateAccessToken(claims.UserID, claims.Username)
	refreshToken, _ := h.jwtService.GenerateRefreshToken(claims.UserID, claims.Username)

	response.Success(c, gin.H{
		"token":         accessToken,
		"refresh_token": refreshToken,
	})
}

// SetJWTService 设置JWT服务
func (h *UserHandler) SetJWTService(jwtSvc *service.JWTService) {
	h.jwtService = jwtSvc
}

// FollowUser 关注用户
func (h *UserHandler) FollowUser(c *gin.Context) {
	userID := c.Param("id")
	currentUserID := c.GetString("user_id")

	if userID == currentUserID {
		response.BadRequest(c, "cannot follow yourself")
		return
	}

	err := h.userService.FollowUser(c.Request.Context(), currentUserID, userID)
	if err != nil {
		response.InternalServerError(c, "failed to follow user")
		return
	}

	response.Success(c, gin.H{"success": true})
}

// UnfollowUser 取消关注用户
func (h *UserHandler) UnfollowUser(c *gin.Context) {
	userID := c.Param("id")
	currentUserID := c.GetString("user_id")

	err := h.userService.UnfollowUser(c.Request.Context(), currentUserID, userID)
	if err != nil {
		response.InternalServerError(c, "failed to unfollow user")
		return
	}

	response.Success(c, gin.H{"success": true})
}

// BlockUser 拉黑用户
func (h *UserHandler) BlockUser(c *gin.Context) {
	targetUserID := c.Param("id")
	currentUserID := c.GetString("user_id")

	if targetUserID == currentUserID {
		response.BadRequest(c, "cannot block yourself")
		return
	}

	err := h.userService.BlockUser(c.Request.Context(), currentUserID, targetUserID)
	if err != nil {
		if se, ok := err.(*service.ServiceError); ok {
			response.Error(c, se.Code, se.Message)
			return
		}
		response.InternalServerError(c, "failed to block user")
		return
	}

	response.Success(c, gin.H{"success": true})
}

// UnblockUser 取消拉黑
func (h *UserHandler) UnblockUser(c *gin.Context) {
	targetUserID := c.Param("id")
	currentUserID := c.GetString("user_id")

	if targetUserID == currentUserID {
		response.BadRequest(c, "cannot unblock yourself")
		return
	}

	err := h.userService.UnblockUser(c.Request.Context(), currentUserID, targetUserID)
	if err != nil {
		if se, ok := err.(*service.ServiceError); ok {
			response.Error(c, se.Code, se.Message)
			return
		}
		response.InternalServerError(c, "failed to unblock user")
		return
	}

	response.Success(c, gin.H{"success": true})
}

// GetBlockedUsers 获取黑名单列表
func (h *UserHandler) GetBlockedUsers(c *gin.Context) {
	currentUserID := c.GetString("user_id")
	if currentUserID == "" {
		response.Unauthorized(c, "")
		return
	}

	page, _ := strconv.Atoi(c.DefaultQuery("page", "1"))
	pageSize, _ := strconv.Atoi(c.DefaultQuery("page_size", "20"))
	if page <= 0 {
		page = 1
	}
	if pageSize <= 0 {
		pageSize = 20
	}

	users, total, err := h.userService.GetBlockedUsers(c.Request.Context(), currentUserID, page, pageSize)
	if err != nil {
		response.InternalServerError(c, "failed to get blocked users")
		return
	}

	userIDs := make([]string, len(users))
	for i, u := range users {
		userIDs[i] = u.ID
	}
	postsCountMap, _ := h.userService.GetUserPostCountBatch(c.Request.Context(), userIDs)
	userResponses := dto.ConvertUsersToResponseWithMutualFollowAndPostsCount(users, nil, postsCountMap)
	response.Paginated(c, userResponses, total, page, pageSize)
}

// GetBlockStatus 获取拉黑状态
func (h *UserHandler) GetBlockStatus(c *gin.Context) {
	targetUserID := c.Param("id")
	currentUserID := c.GetString("user_id")
	if currentUserID == "" {
		response.Unauthorized(c, "")
		return
	}
	if targetUserID == "" {
		response.BadRequest(c, "target user id is required")
		return
	}

	isBlocked, err := h.userService.IsBlocked(c.Request.Context(), currentUserID, targetUserID)
	if err != nil {
		response.InternalServerError(c, "failed to get block status")
		return
	}

	response.Success(c, gin.H{"is_blocked": isBlocked})
}

// GetFollowingList 获取关注列表
func (h *UserHandler) GetFollowingList(c *gin.Context) {
	userID := c.Param("id")
	currentUserID := c.GetString("user_id")
	page := c.DefaultQuery("page", "1")
	pageSize := c.DefaultQuery("page_size", "20")

	users, err := h.userService.GetFollowingList(c.Request.Context(), userID, page, pageSize)
	if err != nil {
		response.InternalServerError(c, "failed to get following list")
		return
	}

	// 如果已登录，获取双向关注状态和实时计算的帖子数量
	var userResponses []*dto.UserResponse
	if currentUserID != "" && len(users) > 0 {
		userIDs := make([]string, len(users))
		for i, u := range users {
			userIDs[i] = u.ID
		}
		statusMap, _ := h.userService.GetMutualFollowStatus(c.Request.Context(), currentUserID, userIDs)
		postsCountMap, _ := h.userService.GetUserPostCountBatch(c.Request.Context(), userIDs)
		userResponses = dto.ConvertUsersToResponseWithMutualFollowAndPostsCount(users, statusMap, postsCountMap)
	} else if len(users) > 0 {
		userIDs := make([]string, len(users))
		for i, u := range users {
			userIDs[i] = u.ID
		}
		postsCountMap, _ := h.userService.GetUserPostCountBatch(c.Request.Context(), userIDs)
		userResponses = dto.ConvertUsersToResponseWithMutualFollowAndPostsCount(users, nil, postsCountMap)
	} else {
		userResponses = dto.ConvertUsersToResponse(users)
	}

	response.Success(c, gin.H{
		"list": userResponses,
	})
}

// GetFollowersList 获取粉丝列表
func (h *UserHandler) GetFollowersList(c *gin.Context) {
	userID := c.Param("id")
	currentUserID := c.GetString("user_id")
	page := c.DefaultQuery("page", "1")
	pageSize := c.DefaultQuery("page_size", "20")

	fmt.Printf("[DEBUG] GetFollowersList: userID=%s, currentUserID=%s\n", userID, currentUserID)

	users, err := h.userService.GetFollowersList(c.Request.Context(), userID, page, pageSize)
	if err != nil {
		response.InternalServerError(c, "failed to get followers list")
		return
	}

	fmt.Printf("[DEBUG] GetFollowersList: found %d users\n", len(users))

	// 如果已登录，获取双向关注状态和实时计算的帖子数量
	var userResponses []*dto.UserResponse
	if currentUserID != "" && len(users) > 0 {
		userIDs := make([]string, len(users))
		for i, u := range users {
			userIDs[i] = u.ID
		}
		fmt.Printf("[DEBUG] GetFollowersList: checking mutual follow status for userIDs=%v\n", userIDs)
		statusMap, _ := h.userService.GetMutualFollowStatus(c.Request.Context(), currentUserID, userIDs)
		postsCountMap, _ := h.userService.GetUserPostCountBatch(c.Request.Context(), userIDs)
		userResponses = dto.ConvertUsersToResponseWithMutualFollowAndPostsCount(users, statusMap, postsCountMap)
	} else if len(users) > 0 {
		userIDs := make([]string, len(users))
		for i, u := range users {
			userIDs[i] = u.ID
		}
		postsCountMap, _ := h.userService.GetUserPostCountBatch(c.Request.Context(), userIDs)
		userResponses = dto.ConvertUsersToResponseWithMutualFollowAndPostsCount(users, nil, postsCountMap)
	} else {
		userResponses = dto.ConvertUsersToResponse(users)
	}

	response.Success(c, gin.H{
		"list": userResponses,
	})
}

// CheckUsername 检查用户名是否可用
func (h *UserHandler) CheckUsername(c *gin.Context) {
	username := c.Query("username")
	if username == "" {
		response.BadRequest(c, "username is required")
		return
	}

	available, err := h.userService.CheckUsernameAvailable(c.Request.Context(), username)
	if err != nil {
		response.InternalServerError(c, "failed to check username")
		return
	}

	response.Success(c, gin.H{"available": available})
}

// ChangePassword 修改密码
func (h *UserHandler) ChangePassword(c *gin.Context) {
	currentUserID := c.GetString("user_id")

	type ChangePasswordRequest struct {
		OldPassword      string `json:"old_password" binding:"required"`
		NewPassword      string `json:"new_password" binding:"required,min=6"`
		VerificationCode string `json:"verification_code" binding:"required"`
	}

	var req ChangePasswordRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		response.BadRequest(c, err.Error())
		return
	}

	err := h.userService.ChangePassword(c.Request.Context(), currentUserID, req.OldPassword, req.NewPassword, req.VerificationCode)
	if err != nil {
		if se, ok := err.(*service.ServiceError); ok {
			response.Error(c, se.Code, se.Message)
			return
		}
		response.InternalServerError(c, "failed to change password")
		return
	}

	response.Success(c, gin.H{"success": true})
}

// SendChangePasswordCode 发送修改密码验证码
func (h *UserHandler) SendChangePasswordCode(c *gin.Context) {
	currentUserID := c.GetString("user_id")
	if currentUserID == "" {
		response.Unauthorized(c, "")
		return
	}

	err := h.userService.SendChangePasswordCode(c.Request.Context(), currentUserID)
	if err != nil {
		if se, ok := err.(*service.ServiceError); ok {
			response.Error(c, se.Code, se.Message)
			return
		}
		response.InternalServerError(c, "failed to send change password code")
		return
	}

	response.Success(c, gin.H{"success": true})
}

// Search 搜索用户
func (h *UserHandler) Search(c *gin.Context) {
	keyword := c.Query("keyword")
	page, _ := strconv.Atoi(c.DefaultQuery("page", "1"))
	pageSize, _ := strconv.Atoi(c.DefaultQuery("page_size", "20"))

	users, total, err := h.userService.Search(c.Request.Context(), keyword, page, pageSize)
	if err != nil {
		response.InternalServerError(c, "failed to search users")
		return
	}

	// 获取实时计算的帖子数量
	var userResponses []*dto.UserResponse
	if len(users) > 0 {
		userIDs := make([]string, len(users))
		for i, u := range users {
			userIDs[i] = u.ID
		}
		postsCountMap, _ := h.userService.GetUserPostCountBatch(c.Request.Context(), userIDs)
		userResponses = dto.ConvertUsersToResponseWithMutualFollowAndPostsCount(users, nil, postsCountMap)
	} else {
		userResponses = dto.ConvertUsersToResponse(users)
	}

	response.Paginated(c, userResponses, total, page, pageSize)
}