Get the internal thread and treat threadid as op, properly attach upload to post

pkg/gcsql/threads.go

@@ -1,6 +1,7 @@
 package gcsql
 
 import (
+	"database/sql"
 	"errors"
 	"strconv"
 )
@@ -47,6 +48,17 @@ func GetThread(threadID int) (*Thread, error) {
 	return thread, err
 }
 
+// GetTopPostThreadID gets the thread ID from the database, given the post ID of a top post
+func GetTopPostThreadID(opID int) (int, error) {
+	const query = `SELECT thread_id FROM DBPREFIXposts WHERE id = ? and is_top_post`
+	var threadID int
+	err := QueryRowSQL(query, interfaceSlice(opID), interfaceSlice(&threadID))
+	if err == sql.ErrNoRows {
+		err = ErrThreadDoesNotExist
+	}
+	return threadID, err
+}
+
 // GetThreadsWithBoardID queries the database for the threads with the given board ID from the database.
 // If onlyNotDeleted is true, it omits deleted threads and threads that were removed because the max
 // thread limit was reached

pkg/gcsql/uploads.go

@@ -56,6 +56,7 @@ func (p *Post) AttachFile(upload *Upload) error {
 	if err != nil {
 		return err
 	}
+	upload.PostID = p.ID
 	if _, err = ExecSQL(query,
 		&upload.PostID, &upload.FileOrder, &upload.OriginalFilename, &upload.Filename, &upload.Checksum, &upload.FileSize,
 		&upload.IsSpoilered, &upload.ThumbnailWidth, &upload.ThumbnailHeight, &upload.Width, &upload.Height,

pkg/posting/post.go

@@ -63,15 +63,30 @@ func MakePost(writer http.ResponseWriter, request *http.Request) {
 	post.IP = gcutil.GetRealIP(request)
 	var err error
 	threadidStr := request.FormValue("threadid")
+	// to avoid potential hiccups, we'll just treat the "threadid" form field as the OP ID and convert it internally
+	// to the real thread ID
+	var opID int
 	if threadidStr != "" {
 		// post is a reply
-		if post.ThreadID, err = strconv.Atoi(threadidStr); err != nil {
-			errEv.Str("threadid", threadidStr).Caller().Msg("Invalid threadid value")
+		if opID, err = strconv.Atoi(threadidStr); err != nil {
+			errEv.Err(err).
+				Str("opIDstr", threadidStr).
+				Caller().Msg("Invalid threadid value")
 			serverutil.ServeError(writer, "Invalid form data (invalid threadid)", wantsJSON, map[string]interface{}{
 				"threadid": threadidStr,
 			})
 			return
 		}
+		if opID > 0 {
+			if post.ThreadID, err = gcsql.GetTopPostThreadID(opID); err != nil {
+				errEv.Err(err).
+					Int("opID", opID).
+					Caller().Send()
+				serverutil.ServeError(writer, err.Error(), wantsJSON, map[string]interface{}{
+					"opID": opID,
+				})
+			}
+		}
 	}
 
 	boardidStr := request.FormValue("boardid")