go_blog/handlers/auth.go

package handlers

import (
	"net/http"

	"github.com/gin-contrib/sessions"
	"github.com/gin-gonic/gin"
	"gorm.io/gorm"

	"go_blog/models"
)

// LoginPage renders the login form.
func LoginPage() gin.HandlerFunc {
	return func(c *gin.Context) {
		tr := getTr(c)
		data := DefaultData(c)
		data["Title"] = tr["page_login"]
		if c.Query("error") == "1" {
			data["Error"] = tr["login_error"]
		}
		c.HTML(http.StatusOK, "login", data)
	}
}

// Login processes the login form submission.
func Login(db *gorm.DB) gin.HandlerFunc {
	return func(c *gin.Context) {
		username := c.PostForm("username")
		password := c.PostForm("password")

		var user models.User
		if err := db.Where("username = ?", username).First(&user).Error; err != nil {
			c.Redirect(http.StatusFound, "/login?error=1")
			return
		}

		if !user.CheckPassword(password) {
			c.Redirect(http.StatusFound, "/login?error=1")
			return
		}

		// Refuse login for non-normal accounts (disabled / locked / unactivated).
		if user.Status != models.StatusNormal {
			c.Redirect(http.StatusFound, "/login?error=1")
			return
		}

		// Create session.
		session := sessions.Default(c)
		session.Set("user_id", user.ID)
		session.Set("username", user.Username)
		if err := session.Save(); err != nil {
			c.String(http.StatusInternalServerError, "Failed to save session")
			return
		}

		// Redirect based on user role: admins to /admin, others to home
		if user.Role == models.RoleAdmin {
			c.Redirect(http.StatusFound, "/admin")
		} else {
			c.Redirect(http.StatusFound, "/")
		}
	}
}

// Logout clears the session and redirects home.
func Logout() gin.HandlerFunc {
	return func(c *gin.Context) {
		session := sessions.Default(c)
		session.Clear()
		session.Save()
		c.Redirect(http.StatusFound, "/")
	}
}