// file name: post_service.go
package appservice

import (
	"bbs-backend/api/request"
	"bbs-backend/common/errcode"
	"bbs-backend/dal"
	"bbs-backend/dal/model"
	"bbs-backend/logic/domainservice"
	"github.com/dgrijalva/jwt-go"
	"github.com/gin-gonic/gin"
	"strings"
)

func CreatePost(c *gin.Context, req request.CreatePostRequest) (*model.Post, error) {
	// 获取当前用户的 ID
	userID, err := getUserIDFromToken(c)
	if err != nil {
		return nil, errcode.ErrUnauthorized
	}

	post := &model.Post{
		Title:      req.Title,
		Content:    req.Content,
		AuthorID:   userID,
		CategoryID: req.CategoryID,
	}

	// 处理标签
	var tags []model.Tag
	for _, tagName := range req.Tags {
		var tag model.Tag
		// 检查标签是否存在，如果不存在则创建
		if err := dal.DB.Where("name = ?", tagName).FirstOrCreate(&tag, model.Tag{Name: tagName}).Error; err != nil {
			return nil, errcode.ErrInternalServerError
		}
		tags = append(tags, tag)
	}
	post.Tags = tags

	err = domainservice.CreatePostDomainService(post)
	if err != nil {
		return nil, errcode.ErrInternalServerError
	}

	return post, nil
}

func getUserIDFromToken(c *gin.Context) (uint, error) {
	authHeader := c.GetHeader("Authorization")
	if authHeader == "" {
		return 0, errcode.ErrUnauthorized
	}

	tokenString := strings.Replace(authHeader, "Bearer ", "", 1)
	token, err := jwt.Parse(tokenString, func(token *jwt.Token) (interface{}, error) {
		return []byte("your_secret_key"), nil
	})

	if err != nil {
		return 0, errcode.ErrUnauthorized
	}

	claims, ok := token.Claims.(jwt.MapClaims)
	if !ok || !token.Valid {
		return 0, errcode.ErrUnauthorized
	}

	userID, ok := claims["user_id"].(float64)
	if !ok {
		return 0, errcode.ErrUnauthorized
	}

	return uint(userID), nil
}

func GetPost(postID uint) (*model.Post, error) {
	post, err := domainservice.GetPostDomainService(postID)
	if err != nil {
		return nil, errcode.ErrNotFound
	}
	return post, nil
}

func GetPosts(req request.GetPostsRequest) ([]*model.Post, error) {
	posts, err := domainservice.GetPostsDomainService(req)
	if err != nil {
		return nil, errcode.ErrInternalServerError
	}
	return posts, nil
}