Implement CRUD operations for blog posts with Create, Edit, and Delete handlers

app/internal/logic/editpostlogic.go

@@ -0,0 +1,67 @@
+package logic
+
+import (
+	"context"
+	"database/sql"
+	"fmt"
+
+	"git.cialloo.com/CiallooWeb/Blog/app/internal/svc"
+	"git.cialloo.com/CiallooWeb/Blog/app/internal/types"
+
+	"github.com/zeromicro/go-zero/core/logx"
+)
+
+type EditPostLogic struct {
+	logx.Logger
+	ctx    context.Context
+	svcCtx *svc.ServiceContext
+}
+
+// Edit an existing blog post
+func NewEditPostLogic(ctx context.Context, svcCtx *svc.ServiceContext) *EditPostLogic {
+	return &EditPostLogic{
+		Logger: logx.WithContext(ctx),
+		ctx:    ctx,
+		svcCtx: svcCtx,
+	}
+}
+
+func (l *EditPostLogic) EditPost(req *types.EditPostReq) (resp *types.EditPostResp, err error) {
+	var coverID sql.NullInt64
+
+	// If cover image key is provided, get the file ID from files table
+	if req.Cover_image_key != "" {
+		query := `SELECT id FROM files WHERE file_key = $1`
+		err := l.svcCtx.DB.QueryRowContext(l.ctx, query, req.Cover_image_key).Scan(&coverID.Int64)
+		if err != nil {
+			if err == sql.ErrNoRows {
+				l.Errorf("Cover image file not found with key: %s", req.Cover_image_key)
+				return nil, fmt.Errorf("cover image not found")
+			}
+			l.Errorf("Failed to get cover image file: %v", err)
+			return nil, err
+		}
+		coverID.Valid = true
+	}
+
+	// Update post with updated_at timestamp
+	query := `UPDATE posts SET title = $1, content = $2, cover_id = $3, updated_at = CURRENT_TIMESTAMP WHERE id = $4`
+	result, err := l.svcCtx.DB.ExecContext(l.ctx, query, req.Title, req.Content, coverID, req.Post_id)
+	if err != nil {
+		l.Errorf("Failed to update post: %v", err)
+		return nil, err
+	}
+
+	// Check if post exists
+	rowsAffected, err := result.RowsAffected()
+	if err != nil {
+		l.Errorf("Failed to get rows affected: %v", err)
+		return nil, err
+	}
+	if rowsAffected == 0 {
+		l.Errorf("Post not found with id: %s", req.Post_id)
+		return nil, fmt.Errorf("post not found")
+	}
+
+	return &types.EditPostResp{}, nil
+}