react-ui: Add support to display Chinese (#713)

* react-ui: Add support to display Chinese

llm-tgi microservice from GenAIComps has encoded each text, so Chinese
response will be shown as hexadecimal in react UI. Add support to decode
and display the response in Chinese. Also return raw response if no
pattern found.

Signed-off-by: Cathy Zhang <cathy.zhang@intel.com>
Signed-off-by: Ruoyu Ying <ruoyu.ying@intel.com>

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

---------

Signed-off-by: Cathy Zhang <cathy.zhang@intel.com>
Signed-off-by: Ruoyu Ying <ruoyu.ying@intel.com>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

ChatQnA/docker/ui/react/src/redux/Conversation/ConversationSlice.ts

@@ -162,7 +162,21 @@ export const doConversation = (conversationRequest: ConversationRequest) => {
             const match = msg.data.match(/b'([^']*)'/);
             if (match && match[1] != "</s>") {
               const extractedText = match[1];
-              result += extractedText;
+
+              // Check for the presence of \x hexadecimal
+              if (extractedText.includes("\\x")) {
+                // Decode Chinese (or other non-ASCII characters)
+                const decodedText = decodeEscapedBytes(extractedText);
+                result += decodedText;
+              } else {
+                result += extractedText;
+              }
+            } else if (!match) {
+              // Return data without pattern
+              result += msg?.data;
+            }
+            // Store back result if it is not null
+            if (result) {
               store.dispatch(setOnGoingResult(result));
             }
           } catch (e) {
@@ -195,3 +209,13 @@ export const doConversation = (conversationRequest: ConversationRequest) => {
     console.log(err);
   }
 };
+
+// decode \x hexadecimal encoding
+function decodeEscapedBytes(str: string): string {
+  // Convert the byte portion separated by \x into a byte array and decode it into a UTF-8 string
+  const byteArray: number[] = str
+    .split("\\x")
+    .slice(1)
+    .map((byte: string) => parseInt(byte, 16));
+  return new TextDecoder("utf-8").decode(new Uint8Array(byteArray));
+}