Blog/app/internal/logic/createpostlogic.go

package logic

import (
	"context"
	"database/sql"
	"fmt"

	"git.cialloo.com/CiallooWeb/Blog/app/internal/svc"
	"git.cialloo.com/CiallooWeb/Blog/app/internal/types"
	"git.cialloo.com/CiallooWeb/Blog/app/internal/utils"

	"github.com/zeromicro/go-zero/core/logx"
)

type CreatePostLogic struct {
	logx.Logger
	ctx    context.Context
	svcCtx *svc.ServiceContext
}

// Create a new blog post
func NewCreatePostLogic(ctx context.Context, svcCtx *svc.ServiceContext) *CreatePostLogic {
	return &CreatePostLogic{
		Logger: logx.WithContext(ctx),
		ctx:    ctx,
		svcCtx: svcCtx,
	}
}

func (l *CreatePostLogic) CreatePost(req *types.CreatePostReq) (resp *types.CreatePostResp, err error) {
	// Start a transaction
	tx, err := l.svcCtx.DB.BeginTx(l.ctx, nil)
	if err != nil {
		l.Errorf("Failed to begin transaction: %v", err)
		return nil, err
	}
	defer tx.Rollback()

	// Extract all image file keys from content
	imageKeys, err := utils.ExtractImageKeysFromContent(req.Content)
	if err != nil {
		l.Errorf("Failed to parse content: %v", err)
		return nil, fmt.Errorf("invalid content format")
	}

	// Extract all archive file keys from content
	archiveKeys, err := utils.ExtractArchiveKeysFromContent(req.Content)
	if err != nil {
		l.Errorf("Failed to parse archive files from content: %v", err)
		return nil, fmt.Errorf("invalid content format")
	}

	// Combine all file keys
	allFileKeys := append(imageKeys, archiveKeys...)

	// Extract all hashtags from content
	hashtags, err := utils.ExtractHashtagsFromContent(req.Content)
	if err != nil {
		l.Errorf("Failed to parse hashtags from content: %v", err)
		return nil, fmt.Errorf("invalid content format")
	}

	// Migrate cover image from tmpfiles to files if provided
	var coverID sql.NullInt64
	if req.CoverImageKey != "" {
		fileID, err := l.migrateFileFromTmpToFiles(tx, req.CoverImageKey)
		if err != nil {
			return nil, err
		}
		coverID.Int64 = fileID
		coverID.Valid = true
	}

	// Migrate all content files (images and archives) from tmpfiles to files
	for _, fileKey := range allFileKeys {
		_, err := l.migrateFileFromTmpToFiles(tx, fileKey)
		if err != nil {
			l.Errorf("Failed to migrate content file %s: %v", fileKey, err)
			// Continue with other files, don't fail the whole operation
		}
	}

	// Insert new post
	var postID int64
	postQuery := `INSERT INTO posts (title, content, cover_id) VALUES ($1, $2, $3) RETURNING id`
	err = tx.QueryRowContext(l.ctx, postQuery, req.Title, req.Content, coverID).Scan(&postID)
	if err != nil {
		l.Errorf("Failed to create post: %v", err)
		return nil, err
	}

	// Create or get hashtag IDs and link them to the post
	for _, tagName := range hashtags {
		var tagID int64

		// Try to get existing hashtag
		getTagQuery := `SELECT id FROM hashtags WHERE name = $1`
		err := tx.QueryRowContext(l.ctx, getTagQuery, tagName).Scan(&tagID)

		if err == sql.ErrNoRows {
			// Hashtag doesn't exist, create it
			createTagQuery := `INSERT INTO hashtags (name) VALUES ($1) RETURNING id`
			err = tx.QueryRowContext(l.ctx, createTagQuery, tagName).Scan(&tagID)
			if err != nil {
				l.Errorf("Failed to create hashtag %s: %v", tagName, err)
				continue
			}
		} else if err != nil {
			l.Errorf("Failed to get hashtag %s: %v", tagName, err)
			continue
		}

		// Link hashtag to post
		linkQuery := `INSERT INTO post_hashtags (post_id, hashtag_id) VALUES ($1, $2) ON CONFLICT DO NOTHING`
		_, err = tx.ExecContext(l.ctx, linkQuery, postID, tagID)
		if err != nil {
			l.Errorf("Failed to link hashtag %s to post: %v", tagName, err)
			// Continue with other hashtags
		}
	}

	// Commit transaction
	if err = tx.Commit(); err != nil {
		l.Errorf("Failed to commit transaction: %v", err)
		return nil, err
	}

	return &types.CreatePostResp{
		PostId: fmt.Sprintf("%d", postID),
	}, nil
}

// migrateFileFromTmpToFiles moves a file from tmpfiles to files table
func (l *CreatePostLogic) migrateFileFromTmpToFiles(tx *sql.Tx, fileKey string) (int64, error) {
	// Check if file already exists in files table
	var existingID int64
	checkQuery := `SELECT id FROM files WHERE file_key = $1`
	err := tx.QueryRowContext(l.ctx, checkQuery, fileKey).Scan(&existingID)
	if err == nil {
		// File already exists, return its ID
		return existingID, nil
	}
	if err != sql.ErrNoRows {
		l.Errorf("Failed to check existing file: %v", err)
		return 0, err
	}

	// Verify file exists in tmpfiles table
	var fileName string
	tmpQuery := `SELECT file_name FROM tmpfiles WHERE key = $1`
	err = tx.QueryRowContext(l.ctx, tmpQuery, fileKey).Scan(&fileName)
	if err != nil {
		if err == sql.ErrNoRows {
			l.Errorf("File not found in tmpfiles with key: %s", fileKey)
			return 0, fmt.Errorf("file not found")
		}
		l.Errorf("Failed to get tmpfile: %v", err)
		return 0, err
	}

	// Insert into files table
	var fileID int64
	fileQuery := `INSERT INTO files (file_name, file_key) VALUES ($1, $2) RETURNING id`
	err = tx.QueryRowContext(l.ctx, fileQuery, fileName, fileKey).Scan(&fileID)
	if err != nil {
		l.Errorf("Failed to insert file record: %v", err)
		return 0, err
	}

	// Delete from tmpfiles
	deleteQuery := `DELETE FROM tmpfiles WHERE key = $1`
	_, err = tx.ExecContext(l.ctx, deleteQuery, fileKey)
	if err != nil {
		l.Errorf("Failed to delete tmpfile: %v", err)
		// Don't fail the operation for this
	}

	return fileID, nil
}