providerrefactor part1

src/providers/sqlite3/queries/translate.js

@@ -0,0 +1,51 @@
+function quoteIdentifiers(sql) {
+  return sql.replace(/\[([^\]]+)]/g, '"$1"');
+}
+
+function moveReturning(sql) {
+  const output = /\bOUTPUT\s+([\s\S]*?)(?=\bVALUES\b|\bWHERE\b)/i.exec(sql);
+  if (!output) return sql;
+
+  const columns = output[1]
+    .split(',')
+    .map((column) => column.trim().replace(/\bINSERTED\./gi, ''))
+    .join(', ');
+  const withoutOutput = sql.slice(0, output.index) + sql.slice(output.index + output[0].length);
+  return `${withoutOutput.trim().replace(/;$/, '')}\nRETURNING ${columns}`;
+}
+
+function moveTop(sql) {
+  const matches = [...sql.matchAll(/\bTOP\s*\(?\s*(\d+)\s*\)?\s*/gi)];
+  if (matches.length === 0) return sql;
+  if (matches.length > 1) {
+    // Complex nested queries are supplied as compatibility exports until
+    // their provider-specific store paths are converted. Do not corrupt them
+    // by appending one LIMIT to the outer statement.
+    return sql;
+  }
+  return `${sql.replace(matches[0][0], '').trim().replace(/;$/, '')}\nLIMIT ${matches[0][1]}`;
+}
+
+/** Convert the common, context-free subset of MSSQL query syntax to SQLite. */
+export function sqliteQuery(sql) {
+  if (typeof sql !== 'string') return sql;
+
+  let result = quoteIdentifiers(sql)
+    .replace(/\bISNULL\s*\(/gi, 'IFNULL(')
+    .replace(/\bSYSUTCDATETIME\s*\(\s*\)/gi, "strftime('%Y-%m-%dT%H:%M:%fZ', 'now')")
+    .replace(/\bCAST\s*\(([^()]+?)\s+AS\s+INT\s*\)/gi, 'CAST($1 AS INTEGER)');
+  result = moveReturning(result);
+  result = moveTop(result);
+  return result;
+}
+
+export function translateQueries(module, moduleName) {
+  return Object.fromEntries(
+    Object.entries(module).map(([name, value]) => [
+      name,
+      typeof value === 'string' && /\s/.test(value)
+        ? sqliteQuery(value)
+        : value,
+    ]),
+  );
+}