Add btoa, atob

1 files changed, 24 insertions, 0 deletions

diff --git a/src/js/base64.nim b/src/js/base64.nim
new file mode 100644
index 00000000..9b61f604
--- /dev/null
+++ b/src/js/base64.nim
@@ -0,0 +1,24 @@
+import unicode
+import std/base64
+
+import js/domexception
+import utils/opt
+
+proc atob*(data: string): DOMResult[string] =
+  try:
+    return ok(base64.decode(data))
+  except ValueError:
+    return err(newDOMException("Invalid character in string",
+      "InvalidCharacterError"))
+
+proc btoa*(data: string): DOMResult[string] =
+  # For some incomprehensible reason, this must return a DOMException
+  # for strings with chars not in latin-1.
+  #TODO this could be a lot more efficient if we just directly passed
+  # is_wide_char from QJS strings.
+  for r in data.runes:
+    if int32(r) <= 0xFF:
+      continue
+    return err(newDOMException("Invalid character in string",
+      "InvalidCharacterError"))
+  return ok(base64.encode(data))