package handlers

import (
	"fmt"
	"io"
	"net/http"
	"os"
	"path/filepath"
	"strings"
	"time"

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

	"go_blog/models"
)

// ProfilePage renders the profile edit page.
func ProfilePage(db *gorm.DB) gin.HandlerFunc {
	return func(c *gin.Context) {
		tr := getTr(c)
		session := sessions.Default(c)
		userID := session.Get("user_id")

		var user models.User
		if err := db.First(&user, userID).Error; err != nil {
			c.String(http.StatusInternalServerError, "User not found")
			return
		}

		data := DefaultData(c)
		data["Title"] = tr["profile_title"]
		data["Profile"] = user

		// Flash messages (success / error).
		if msg := c.Query("saved"); msg == "1" {
			data["Success"] = tr["profile_saved"]
		}
		if msg := c.Query("error"); msg == "pw" {
			data["Error"] = tr["profile_wrong_password"]
		}

		c.HTML(http.StatusOK, "profile", data)
	}
}

// UpdateProfile processes the profile edit form (multipart).
func UpdateProfile(db *gorm.DB, storagePath string) gin.HandlerFunc {
	return func(c *gin.Context) {
		session := sessions.Default(c)
		userID := session.Get("user_id")

		var user models.User
		if err := db.First(&user, userID).Error; err != nil {
			c.Redirect(http.StatusFound, "/profile")
			return
		}

		// --- Text fields ---
		if v := c.PostForm("display_name"); v != "" {
			user.DisplayName = v
		}
		if v := c.PostForm("gender"); v != "" {
			user.Gender = v
		}
		if v := c.PostForm("email"); v != "" {
			user.Email = v
		}
		if v := c.PostForm("birthday"); v != "" {
			if t, err := time.Parse("2006-01-02", v); err == nil {
				user.Birthday = &t
			}
		}

		// --- Avatar upload ---
		file, header, err := c.Request.FormFile("avatar")
		if err == nil {
			defer file.Close()

			// Determine file extension.
			ext := strings.ToLower(filepath.Ext(header.Filename))
			if ext == "" || (ext != ".jpg" && ext != ".jpeg" && ext != ".png" && ext != ".gif" && ext != ".webp") {
				ext = ".jpg"
			}

			// Save under storagePath/avatars/.
			avatarDir := filepath.Join(storagePath, "avatars")
			if err := os.MkdirAll(avatarDir, 0755); err != nil {
				c.Redirect(http.StatusFound, "/profile")
				return
			}

			// Use user ID as filename base to avoid duplicates.
			savedName := fmt.Sprintf("%d%s", user.ID, ext)
			savedPath := filepath.Join(avatarDir, savedName)

			dst, err := os.Create(savedPath)
			if err != nil {
				c.Redirect(http.StatusFound, "/profile")
				return
			}
			defer dst.Close()

			if _, err := io.Copy(dst, file); err != nil {
				c.Redirect(http.StatusFound, "/profile")
				return
			}

			user.Avatar = savedName
			// Update session display immediately.
			session.Set("avatar", savedName)
		}

		// --- Password change ---
		currentPass := c.PostForm("current_password")
		newPass := c.PostForm("new_password")
		if currentPass != "" && newPass != "" {
			if !user.CheckPassword(currentPass) {
				session.Save()
				c.Redirect(http.StatusFound, "/profile?error=pw")
				return
			}
			if err := user.SetPassword(newPass); err != nil {
				session.Save()
				c.Redirect(http.StatusFound, "/profile")
				return
			}
		}

		// Save user record.
		if err := db.Save(&user).Error; err != nil {
			session.Save()
			c.Redirect(http.StatusFound, "/profile")
			return
		}

		// Update display name in session.
		session.Set("display_name", user.DisplayName)
		session.Save()

		c.Redirect(http.StatusFound, "/profile?saved=1")
	}
}