Fix base64 - pure Lua implementation, no external deps

package/src/client2server-unified.lua

@@ -198,15 +198,28 @@ end
 local ws = { sock = nil, connected = false, key = "" }
 
 -- Simple base64 encoder
+-- Pure Lua base64 encoder (no external deps)
 local function base64_encode(data)
-    -- Use openssl for base64 encoding
-    local f = io.popen("echo -n '" .. data:gsub("'", "'\\''") .. "' | openssl base64 -A 2>/dev/null")
-    if f then
-        local result = f:read("*a")
-        f:close()
-        return result:gsub("%s+$", "")
+    local b64_chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"
+    local result = {}
+    for i = 1, #data, 3 do
+        local b1, b2, b3 = string.byte(data, i, i+2)
+        b2 = b2 or 0
+        b3 = b3 or 0
+        table.insert(result, string.sub(b64_chars, math.floor(b1/4)+1, math.floor(b1/4)+1))
+        table.insert(result, string.sub(b64_chars, ((b1%16)*4) + math.floor(b2/16)+1, ((b1%16)*4) + math.floor(b2/16)+1))
+        if i+1 > #data then
+            table.insert(result, "==")
+        else
+            table.insert(result, string.sub(b64_chars, ((b2%16)*4) + math.floor(b3/64)+1, ((b2%16)*4) + math.floor(b3/64)+1))
+            if i+2 > #data then
+                table.insert(result, "=")
+            else
+                table.insert(result, string.sub(b64_chars, (b3%64)+1, (b3%64)+1))
+            end
+        end
     end
-    return ""
+    return table.concat(result)
 end
 
 -- SHA1 (for WebSocket handshake)