1 files changed, 93 insertions, 0 deletions
diff --git a/packages/taler-util/src/globbing/balanced-match.ts b/packages/taler-util/src/globbing/balanced-match.ts
new file mode 100644
index 000000000..0dc35a569
--- /dev/null
+++ b/packages/taler-util/src/globbing/balanced-match.ts
@@ -0,0 +1,93 @@
+/*
+Original work Copyright (C) 2013 Julian Gruber <julian@juliangruber.com>
+Modified work Copyright (C) 2021 Taler Systems S.A.
+
+Permission is hereby granted, free of charge, to any person obtaining a
+copy of this software and associated documentation files (the "Software"),
+to deal in the Software without restriction, including without limitation
+the rights to use, copy, modify, merge, publish, distribute, sublicense,
+and/or sell copies of the Software, and to permit persons to whom the
+Software is furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+*/
+
+export function balanced(a: RegExp | string, b: RegExp | string, str: string) {
+  let myA: string;
+  let myB: string;
+  if (a instanceof RegExp) myA = maybeMatch(a, str)!;
+  else myA = a;
+  if (b instanceof RegExp) myB = maybeMatch(b, str)!;
+  else myB = b;
+
+  const r = range(myA, myB, str);
+
+  return (
+    r && {
+      start: r[0],
+      end: r[1],
+      pre: str.slice(0, r[0]),
+      body: str.slice(r[0]! + myA!.length, r[1]),
+      post: str.slice(r[1]! + myB!.length),
+    }
+  );
+}
+
+/**
+ * @param {RegExp} reg
+ * @param {string} str
+ */
+function maybeMatch(reg: RegExp, str: string) {
+  const m = str.match(reg);
+  return m ? m[0] : null;
+}
+
+balanced.range = range;
+
+/**
+ * @param {string} a
+ * @param {string} b
+ * @param {string} str
+ */
+function range(a: string, b: string, str: string) {
+  let begs: number[];
+  let beg: number;
+  let left, right, result;
+  let ai = str.indexOf(a);
+  let bi = str.indexOf(b, ai + 1);
+  let i = ai;
+
+  if (ai >= 0 && bi > 0) {
+    if (a === b) {
+      return [ai, bi];
+    }
+    begs = [];
+    left = str.length;
+
+    while (i >= 0 && !result) {
+      if (i === ai) {
+        begs.push(i);
+        ai = str.indexOf(a, i + 1);
+      } else if (begs.length === 1) {
+        result = [begs.pop(), bi];
+      } else {
+        beg = begs.pop()!;
+        if (beg < left) {
+          left = beg;
+          right = bi;
+        }
+
+        bi = str.indexOf(b, i + 1);
+      }
+
+      i = ai < bi && ai >= 0 ? ai : bi;
+    }
+
+    if (begs.length) {
+      result = [left, right];
+    }
+  }
+
+  return result;
+}