fix: optimized to reduce rerenders

surfsense_web/components/chat/CodeBlock.tsx

@@ -1,6 +1,6 @@
 "use client";
 
-import React, { useState, useEffect } from "react";
+import React, { useState, useEffect, useMemo, useCallback } from "react";
 import { Prism as SyntaxHighlighter } from "react-syntax-highlighter";
 import {
   oneLight,
@@ -9,13 +9,66 @@ import {
 import { Check, Copy } from "lucide-react";
 import { useTheme } from "next-themes";
 
-// Code block component with syntax highlighting and copy functionality
-export const CodeBlock = ({
-  children,
-  language,
-}: {
+// Constants for styling and configuration
+const COPY_TIMEOUT = 2000;
+
+const BASE_CUSTOM_STYLE = {
+  margin: 0,
+  borderRadius: "0.375rem",
+  fontSize: "0.75rem",
+  lineHeight: "1.5rem",
+  border: "none",
+} as const;
+
+const LINE_PROPS_STYLE = {
+  wordBreak: "break-all" as const,
+  whiteSpace: "pre-wrap" as const,
+  border: "none",
+  borderBottom: "none",
+  paddingLeft: 0,
+  paddingRight: 0,
+  margin: "0.25rem 0",
+} as const;
+
+const CODE_TAG_PROPS = {
+  className: "font-mono",
+  style: {
+    border: "none",
+    background: "var(--syntax-bg)",
+  },
+} as const;
+
+// TypeScript interfaces
+interface CodeBlockProps {
   children: string;
   language: string;
+}
+
+interface LanguageRenderer {
+  (props: { code: string }): React.JSX.Element;
+}
+
+interface SyntaxStyle {
+  [key: string]: React.CSSProperties;
+}
+
+// Memoized fallback component for SSR/hydration
+const FallbackCodeBlock = React.memo(({ children }: { children: string }) => (
+  <div className="bg-muted p-4 rounded-md">
+    <pre className="m-0 p-0 border-0">
+      <code className="text-xs font-mono border-0 leading-6">
+        {children}
+      </code>
+    </pre>
+  </div>
+));
+
+FallbackCodeBlock.displayName = "FallbackCodeBlock";
+
+// Code block component with syntax highlighting and copy functionality
+export const CodeBlock = React.memo<CodeBlockProps>(({
+  children,
+  language,
 }) => {
   const [copied, setCopied] = useState(false);
   const { resolvedTheme, theme } = useTheme();
@@ -26,15 +79,62 @@ export const CodeBlock = ({
     setMounted(true);
   }, []);
 
-  const handleCopy = async () => {
-    await navigator.clipboard.writeText(children);
-    setCopied(true);
-    setTimeout(() => setCopied(false), 2000);
-  };
+  // Memoize theme detection
+  const isDarkTheme = useMemo(() => 
+    mounted && (resolvedTheme === "dark" || theme === "dark"),
+    [mounted, resolvedTheme, theme]
+  );
 
-  // Choose theme based on current system/user preference
-  const isDarkTheme = mounted && (resolvedTheme === "dark" || theme === "dark");
-  const syntaxTheme = isDarkTheme ? oneDark : oneLight;
+  // Memoize syntax theme selection
+  const syntaxTheme = useMemo(() => 
+    isDarkTheme ? oneDark : oneLight,
+    [isDarkTheme]
+  );
+
+  // Memoize enhanced style with theme-specific modifications
+  const enhancedStyle = useMemo<SyntaxStyle>(() => ({
+    ...syntaxTheme,
+    'pre[class*="language-"]': {
+      ...syntaxTheme['pre[class*="language-"]'],
+      margin: 0,
+      border: "none",
+      borderRadius: "0.375rem",
+      background: "var(--syntax-bg)",
+    },
+    'code[class*="language-"]': {
+      ...syntaxTheme['code[class*="language-"]'],
+      border: "none",
+      background: "var(--syntax-bg)",
+    },
+  }), [syntaxTheme]);
+
+  // Memoize custom style with background
+  const customStyle = useMemo(() => ({
+    ...BASE_CUSTOM_STYLE,
+    backgroundColor: "var(--syntax-bg)",
+  }), []);
+
+  // Memoized copy handler
+  const handleCopy = useCallback(async () => {
+    try {
+      await navigator.clipboard.writeText(children);
+      setCopied(true);
+      const timeoutId = setTimeout(() => setCopied(false), COPY_TIMEOUT);
+      return () => clearTimeout(timeoutId);
+    } catch (error) {
+      console.warn("Failed to copy code to clipboard:", error);
+    }
+  }, [children]);
+
+  // Memoized line props with style
+  const lineProps = useMemo(() => ({
+    style: LINE_PROPS_STYLE,
+  }), []);
+
+  // Early return for non-mounted state
+  if (!mounted) {
+    return <FallbackCodeBlock>{children}</FallbackCodeBlock>;
+  }
 
   return (
     <div className="relative my-4 group">
@@ -43,6 +143,7 @@ export const CodeBlock = ({
           onClick={handleCopy}
           className="p-1.5 rounded-md bg-background/80 hover:bg-background border border-border flex items-center justify-center transition-colors"
           aria-label="Copy code"
+          type="button"
         >
           {copied ? (
             <Check size={14} className="text-green-500" />
@@ -51,103 +152,43 @@ export const CodeBlock = ({
           )}
         </button>
       </div>
-      {mounted ? (
-        <SyntaxHighlighter
-          language={language || "text"}
-          style={{
-            ...syntaxTheme,
-            'pre[class*="language-"]': {
-              ...syntaxTheme['pre[class*="language-"]'],
-              margin: 0,
-              border: "none",
-              borderRadius: "0.375rem",
-              background: "var(--syntax-bg)",
-            },
-            'code[class*="language-"]': {
-              ...syntaxTheme['code[class*="language-"]'],
-              border: "none",
-              background: "var(--syntax-bg)",
-            },
-          }}
-          customStyle={{
-            margin: 0,
-            borderRadius: "0.375rem",
-            fontSize: "0.75rem",
-            lineHeight: "1.5rem",
-            backgroundColor: "var(--syntax-bg)",
-            border: "none",
-          }}
-          codeTagProps={{
-            className: "font-mono",
-            style: {
-              border: "none",
-              background: "var(--syntax-bg)",
-            },
-          }}
-          showLineNumbers={false}
-          wrapLines={false}
-          lineProps={{
-            style: {
-              wordBreak: "break-all",
-              whiteSpace: "pre-wrap",
-              border: "none",
-              borderBottom: "none",
-              paddingLeft: 0,
-              paddingRight: 0,
-              margin: "0.25rem 0",
-            },
-          }}
-          PreTag="div"
-        >
-          {children}
-        </SyntaxHighlighter>
-      ) : (
-        <div className="bg-muted p-4 rounded-md">
-          <pre className="m-0 p-0 border-0">
-            <code className="text-xs font-mono border-0 leading-6">
-              {children}
-            </code>
-          </pre>
-        </div>
-      )}
+      <SyntaxHighlighter
+        language={language || "text"}
+        style={enhancedStyle}
+        customStyle={customStyle}
+        codeTagProps={CODE_TAG_PROPS}
+        showLineNumbers={false}
+        wrapLines={false}
+        lineProps={lineProps}
+        PreTag="div"
+      >
+        {children}
+      </SyntaxHighlighter>
     </div>
   );
-};
+});
 
-// Create language renderer function
-const createLanguageRenderer = (lang: string) => 
-  ({ code }: { code: string }) => (
+CodeBlock.displayName = "CodeBlock";
+
+// Optimized language renderer factory with memoization
+const createLanguageRenderer = (lang: string): LanguageRenderer => {
+  const renderer = ({ code }: { code: string }) => (
     <CodeBlock language={lang}>{code}</CodeBlock>
   );
+  renderer.displayName = `LanguageRenderer(${lang})`;
+  return renderer;
+};
 
-// Define language renderers for common programming languages
-export const languageRenderers = {
-  "javascript": createLanguageRenderer("javascript"),
-  "typescript": createLanguageRenderer("typescript"),
-  "python": createLanguageRenderer("python"),
-  "java": createLanguageRenderer("java"),
-  "csharp": createLanguageRenderer("csharp"),
-  "cpp": createLanguageRenderer("cpp"),
-  "c": createLanguageRenderer("c"),
-  "php": createLanguageRenderer("php"),
-  "ruby": createLanguageRenderer("ruby"),
-  "go": createLanguageRenderer("go"),
-  "rust": createLanguageRenderer("rust"),
-  "swift": createLanguageRenderer("swift"),
-  "kotlin": createLanguageRenderer("kotlin"),
-  "scala": createLanguageRenderer("scala"),
-  "sql": createLanguageRenderer("sql"),
-  "json": createLanguageRenderer("json"),
-  "xml": createLanguageRenderer("xml"),
-  "yaml": createLanguageRenderer("yaml"),
-  "bash": createLanguageRenderer("bash"),
-  "shell": createLanguageRenderer("shell"),
-  "powershell": createLanguageRenderer("powershell"),
-  "dockerfile": createLanguageRenderer("dockerfile"),
-  "html": createLanguageRenderer("html"),
-  "css": createLanguageRenderer("css"),
-  "scss": createLanguageRenderer("scss"),
-  "less": createLanguageRenderer("less"),
-  "markdown": createLanguageRenderer("markdown"),
-  "text": createLanguageRenderer("text"),
-}; 
+// Pre-defined supported languages for better maintainability
+const SUPPORTED_LANGUAGES = [
+  "javascript", "typescript", "python", "java", "csharp", "cpp", "c",
+  "php", "ruby", "go", "rust", "swift", "kotlin", "scala", "sql",
+  "json", "xml", "yaml", "bash", "shell", "powershell", "dockerfile",
+  "html", "css", "scss", "less", "markdown", "text"
+] as const;
+
+// Generate language renderers efficiently
+export const languageRenderers: Record<string, LanguageRenderer> = 
+  Object.fromEntries(
+    SUPPORTED_LANGUAGES.map(lang => [lang, createLanguageRenderer(lang)])
+  );