fix: update bookmark on sqlite database (go-shiori#367)

It used an update and insert at the same time, since the virtual table
cannot have constrants nor upserts we need to try an update the
bookmark content to check for it's existence, inserting it only if the
update fails (don't affect any rows).

This will need to be improved in the future, since not all bookmark
updates require modification of the content table (in my case, I was
testing only updating tags).

internal/database/sqlite.go

@@ -73,7 +73,8 @@ func OpenSQLiteDatabase(databasePath string) (sqliteDB *SQLiteDatabase, err erro
 		CONSTRAINT bookmark_id_FK FOREIGN KEY(bookmark_id) REFERENCES bookmark(id),
 		CONSTRAINT tag_id_FK FOREIGN KEY(tag_id) REFERENCES tag(id))`)
 
-	tx.MustExec(`CREATE VIRTUAL TABLE IF NOT EXISTS bookmark_content USING fts5(title, content, html, docid)`)
+	tx.MustExec(`CREATE VIRTUAL TABLE IF NOT EXISTS bookmark_content
+		USING fts5(title, content, html, docid)`)
 
 	// Alter table if needed
 	if _, err := tx.Exec(`ALTER TABLE account ADD COLUMN owner INTEGER NOT NULL DEFAULT 0`); err != nil {
@@ -119,9 +120,9 @@ func (db *SQLiteDatabase) SaveBookmarks(bookmarks ...model.Bookmark) (result []m
 		url = ?, title = ?,	excerpt = ?, author = ?,
 		public = ?, modified = ?`)
 
-	// stmtInsertBookContent, _ := tx.Preparex(`INSERT OR IGNORE INTO bookmark_content
-	// 	(docid, title, content, html)
-	// 	VALUES (?, ?, ?, ?)`)
+	stmtInsertBookContent, _ := tx.Preparex(`INSERT OR REPLACE INTO bookmark_content
+		(docid, title, content, html)
+		VALUES (?, ?, ?, ?)`)
 
 	stmtUpdateBookContent, _ := tx.Preparex(`UPDATE bookmark_content SET
 		title = ?, content = ?, html = ?
@@ -164,8 +165,13 @@ func (db *SQLiteDatabase) SaveBookmarks(bookmarks ...model.Bookmark) (result []m
 			book.URL, book.Title, book.Excerpt, book.Author, book.Public, book.Modified,
 			book.URL, book.Title, book.Excerpt, book.Author, book.Public, book.Modified)
 
-		stmtUpdateBookContent.MustExec(book.Title, book.Content, book.HTML, book.ID)
-		//stmtInsertBookContent.MustExec(book.ID, book.Title, book.Content, book.HTML)
+		// Try to update it first to check for existence, we can't do an UPSERT here because
+		// bookmant_content is a virtual table
+		res := stmtUpdateBookContent.MustExec(book.Title, book.Content, book.HTML, book.ID)
+		rows, _ := res.RowsAffected()
+		if rows == 0 {
+			stmtInsertBookContent.MustExec(book.ID, book.Title, book.Content, book.HTML)
+		}
 
 		// Save book tags
 		newTags := []model.Tag{}