package handlers

import (
	"net/http"
	"strconv"
	"strings"

	"gateway/config"
	"gateway/models"
	"gateway/utils"

	"github.com/gin-contrib/sessions"
	"github.com/gin-gonic/gin"
	"github.com/jinzhu/gorm"
	"golang.org/x/crypto/bcrypt"
)

func GetLogin(c *gin.Context) {
	returnURL := c.Query("return_url")
	c.HTML(http.StatusOK, "login.html", gin.H{
		"return_url": returnURL,
	})
}

func PostLogin(db *gorm.DB) gin.HandlerFunc {
	return func(c *gin.Context) {
		username := c.PostForm("username")
		password := c.PostForm("password")
		returnURL := c.PostForm("return_url")

		var user models.User
		if err := db.Where("mobile = ?", username).First(&user).Error; err != nil {
			c.HTML(http.StatusUnauthorized, "login.html", gin.H{
				"error":      "用户不存在或密码错误",
				"return_url": returnURL,
			})
			return
		}

		if err := bcrypt.CompareHashAndPassword([]byte(user.Password), []byte(password)); err != nil {
			c.HTML(http.StatusUnauthorized, "login.html", gin.H{
				"error":      "用户不存在或密码错误",
				"return_url": returnURL,
			})
			return
		}

		session := sessions.Default(c)
		session.Set("user", user.ID)
		if err := session.Save(); err != nil {
			utils.Logger.Errorf("Session保存失败: %v", err)
			c.HTML(http.StatusInternalServerError, "login.html", gin.H{
				"error":      "登录状态保存失败",
				"return_url": returnURL,
			})
			return
		}

		if returnURL != "" {
			c.Redirect(http.StatusSeeOther, returnURL)
			return
		}

		c.Redirect(http.StatusSeeOther, "/")
	}
}

func GetRegister(db *gorm.DB) gin.HandlerFunc {
	return func(c *gin.Context) {
		regions, err := getRegions(db)
		if err != nil {
			c.HTML(http.StatusInternalServerError, "register.html", gin.H{"error": "系统错误"})
			return
		}
		c.HTML(http.StatusOK, "register.html", gin.H{"regions": regions})
	}
}

func PostRegister(db *gorm.DB) gin.HandlerFunc {
	return func(c *gin.Context) {
		regionStr, exists := c.GetPostForm("region")
		if !exists {
			handleRegisterError(c, db, "请选择所在地区")
			return
		}

		regionID, err := strconv.ParseUint(regionStr, 10, 32)
		if err != nil {
			handleRegisterError(c, db, "无效的地区参数")
			return
		}

		user := models.User{
			FullName: c.PostForm("fullname"),
			Mobile:   c.PostForm("mobile"),
			RegionID: uint(regionID),
		}

		var region models.Region
		if err := db.First(&region, user.RegionID).Error; err != nil {
			handleRegisterError(c, db, "请选择有效地区")
			return
		}

		if len(user.Mobile) != 11 {
			handleRegisterError(c, db, "手机号格式不正确")
			return
		}

		password := c.PostForm("password")
		hashedPassword, err := bcrypt.GenerateFromPassword([]byte(password), bcrypt.DefaultCost)
		if err != nil {
			utils.Logger.Errorf("密码加密失败: %v", err)
			handleRegisterError(c, db, "注册失败")
			return
		}
		user.Password = string(hashedPassword)

		if err := db.Create(&user).Error; err != nil {
			utils.Logger.Errorf("用户创建失败: %v", err)
			errorMsg := "注册失败"
			if strings.Contains(err.Error(), "UNIQUE constraint failed") {
				errorMsg = "该手机号已注册"
			}
			handleRegisterError(c, db, errorMsg)
			return
		}

		c.Redirect(http.StatusSeeOther, "/login")
	}
}

func Logout(c *gin.Context) {
	session := sessions.Default(c)

	// 使用配置中的session选项
	session.Options(config.GetLogoutSessionOptions())

	// 清除session数据
	session.Clear()

	// 添加清除缓存的 HTTP 头
	c.Header("Cache-Control", "no-cache, no-store, must-revalidate")
	c.Header("Pragma", "no-cache")
	c.Header("Expires", "0")

	// 保存更改
	if err := session.Save(); err != nil {
		utils.Logger.Errorf("退出登录失败: %v", err)
		c.HTML(http.StatusInternalServerError, "error.html", gin.H{"error": "退出登录失败"})
		return
	}

	c.Redirect(http.StatusSeeOther, "/login")
}

func getRegions(db *gorm.DB) ([]models.Region, error) {
	var regions []models.Region
	if err := db.Find(&regions).Error; err != nil {
		utils.Logger.Errorf("获取地区数据失败: %v", err)
		return nil, err
	}
	return regions, nil
}

func handleRegisterError(c *gin.Context, db *gorm.DB, errorMessage string) {
	regions, err := getRegions(db)
	if err != nil {
		c.HTML(http.StatusInternalServerError, "register.html", gin.H{"error": "系统错误"})
		return
	}
	c.HTML(http.StatusBadRequest, "register.html", gin.H{
		"error":   errorMessage,
		"regions": regions,
		"form": gin.H{
			"fullname": c.PostForm("fullname"),
			"mobile":   c.PostForm("mobile"),
		},
	})
}

func GetUserInfo(db *gorm.DB) gin.HandlerFunc {
	return func(c *gin.Context) {
		session := sessions.Default(c)
		userID := session.Get("user")

		if userID == nil {
			c.JSON(http.StatusUnauthorized, gin.H{"error": "未登录"})
			return
		}

		var user models.User
		if err := db.First(&user, userID).Error; err != nil {
			c.JSON(http.StatusInternalServerError, gin.H{"error": "获取用户信息失败"})
			return
		}

		c.JSON(http.StatusOK, gin.H{
			"id":       user.ID,
			"fullName": user.FullName,
			"mobile":   user.Mobile,
		})
	}
}