From ea2831fd774df77bab724b81b50eece85b6988bf Mon Sep 17 00:00:00 2001
From: Oli Larkin <olilarkin@googlemail.com>
Date: Tue, 23 Jan 2024 00:38:02 +0100
Subject: [PATCH] WAM: Fix missing atob in audioworklet #1050

---
 IPlug/WEB/Template/scripts/atob-polyfill.js | 40 +++++++++++++++++++++
 common-web.mk                               |  3 +-
 2 files changed, 42 insertions(+), 1 deletion(-)
 create mode 100644 IPlug/WEB/Template/scripts/atob-polyfill.js

diff --git a/IPlug/WEB/Template/scripts/atob-polyfill.js b/IPlug/WEB/Template/scripts/atob-polyfill.js
new file mode 100644
index 0000000000..a233910b5c
--- /dev/null
+++ b/IPlug/WEB/Template/scripts/atob-polyfill.js
@@ -0,0 +1,40 @@
+// Copied from https://github.com/strophe/strophejs/blob/e06d027/src/polyfills.js#L149
+
+// This code was written by Tyler Akins and has been placed in the
+// public domain.  It would be nice if you left this header intact.
+// Base64 code from Tyler Akins -- http://rumkin.com
+
+/**
+ * Decodes a base64 string.
+ * @param {string} input The string to decode.
+ */
+function atob(input) {
+  var keyStr = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=';
+
+  var output = '';
+  var chr1, chr2, chr3;
+  var enc1, enc2, enc3, enc4;
+  var i = 0;
+  // remove all characters that are not A-Z, a-z, 0-9, +, /, or =
+  input = input.replace(/[^A-Za-z0-9\+\/\=]/g, '');
+  do {
+    enc1 = keyStr.indexOf(input.charAt(i++));
+    enc2 = keyStr.indexOf(input.charAt(i++));
+    enc3 = keyStr.indexOf(input.charAt(i++));
+    enc4 = keyStr.indexOf(input.charAt(i++));
+
+    chr1 = (enc1 << 2) | (enc2 >> 4);
+    chr2 = ((enc2 & 15) << 4) | (enc3 >> 2);
+    chr3 = ((enc3 & 3) << 6) | enc4;
+
+    output = output + String.fromCharCode(chr1);
+
+    if (enc3 !== 64) {
+      output = output + String.fromCharCode(chr2);
+    }
+    if (enc4 !== 64) {
+      output = output + String.fromCharCode(chr3);
+    }
+  } while (i < input.length);
+  return output;
+};
\ No newline at end of file
diff --git a/common-web.mk b/common-web.mk
index 76c1d7e405..a5043f9117 100644
--- a/common-web.mk
+++ b/common-web.mk
@@ -94,7 +94,8 @@ LDFLAGS = -s ALLOW_MEMORY_GROWTH=1 --bind
 # The following settings mean the WASM is delivered as BASE64 and included in the MyPluginName-wam.js file.
 WAM_LDFLAGS = -s EXPORTED_RUNTIME_METHODS="['ccall', 'cwrap', 'setValue', 'UTF8ToString']" \
 -s BINARYEN_ASYNC_COMPILATION=0 \
--s SINGLE_FILE=1
+-s SINGLE_FILE=1 \
+--pre-js=$(IPLUG2_ROOT)/IPlug/WEB/Template/scripts/atob-polyfill.js
 #-s ENVIRONMENT=worker
 
 WEB_LDFLAGS = -s EXPORTED_FUNCTIONS=$(WEB_EXPORTS) \