feat: ai elements (#1143)

components/elements/reasoning.tsx

@@ -0,0 +1,171 @@
+'use client';
+
+import { useControllableState } from '@radix-ui/react-use-controllable-state';
+import {
+  Collapsible,
+  CollapsibleContent,
+  CollapsibleTrigger,
+} from '@/components/ui/collapsible';
+import { cn } from '@/lib/utils';
+import { BrainIcon, ChevronDownIcon } from 'lucide-react';
+import type { ComponentProps } from 'react';
+import { createContext, memo, useContext, useEffect, useState } from 'react';
+import { Response } from './response';
+
+type ReasoningContextValue = {
+  isStreaming: boolean;
+  isOpen: boolean;
+  setIsOpen: (open: boolean) => void;
+  duration: number;
+};
+
+const ReasoningContext = createContext<ReasoningContextValue | null>(null);
+
+const useReasoning = () => {
+  const context = useContext(ReasoningContext);
+  if (!context) {
+    throw new Error('Reasoning components must be used within Reasoning');
+  }
+  return context;
+};
+
+export type ReasoningProps = ComponentProps<typeof Collapsible> & {
+  isStreaming?: boolean;
+  open?: boolean;
+  defaultOpen?: boolean;
+  onOpenChange?: (open: boolean) => void;
+  duration?: number;
+};
+
+const AUTO_CLOSE_DELAY = 1000;
+const MS_IN_S = 1000;
+
+export const Reasoning = memo(
+  ({
+    className,
+    isStreaming = false,
+    open,
+    defaultOpen = true,
+    onOpenChange,
+    duration: durationProp,
+    children,
+    ...props
+  }: ReasoningProps) => {
+    const [isOpen, setIsOpen] = useControllableState({
+      prop: open,
+      defaultProp: defaultOpen,
+      onChange: onOpenChange,
+    });
+    const [duration, setDuration] = useControllableState({
+      prop: durationProp,
+      defaultProp: 0,
+    });
+
+    const [hasAutoClosedRef, setHasAutoClosedRef] = useState(false);
+    const [startTime, setStartTime] = useState<number | null>(null);
+
+    // Track duration when streaming starts and ends
+    useEffect(() => {
+      if (isStreaming) {
+        if (startTime === null) {
+          setStartTime(Date.now());
+        }
+      } else if (startTime !== null) {
+        setDuration(Math.round((Date.now() - startTime) / MS_IN_S));
+        setStartTime(null);
+      }
+    }, [isStreaming, startTime, setDuration]);
+
+    // Auto-open when streaming starts, auto-close when streaming ends (once only)
+    useEffect(() => {
+      if (defaultOpen && !isStreaming && isOpen && !hasAutoClosedRef) {
+        // Add a small delay before closing to allow user to see the content
+        const timer = setTimeout(() => {
+          setIsOpen(false);
+          setHasAutoClosedRef(true);
+        }, AUTO_CLOSE_DELAY);
+
+        return () => clearTimeout(timer);
+      }
+    }, [isStreaming, isOpen, defaultOpen, setIsOpen, hasAutoClosedRef]);
+
+    const handleOpenChange = (newOpen: boolean) => {
+      setIsOpen(newOpen);
+    };
+
+    return (
+      <ReasoningContext.Provider
+        value={{ isStreaming, isOpen, setIsOpen, duration }}
+      >
+        <Collapsible
+          className={cn('not-prose mb-4', className)}
+          onOpenChange={handleOpenChange}
+          open={isOpen}
+          {...props}
+        >
+          {children}
+        </Collapsible>
+      </ReasoningContext.Provider>
+    );
+  },
+);
+
+export type ReasoningTriggerProps = ComponentProps<typeof CollapsibleTrigger>;
+
+export const ReasoningTrigger = memo(
+  ({ className, children, ...props }: ReasoningTriggerProps) => {
+    const { isStreaming, isOpen, duration } = useReasoning();
+
+    return (
+      <CollapsibleTrigger
+        className={cn(
+          'flex items-center gap-2 text-muted-foreground text-sm',
+          className,
+        )}
+        {...props}
+      >
+        {children ?? (
+          <>
+            <BrainIcon className="size-4" />
+            {isStreaming || duration === 0 ? (
+              <p>Thinking...</p>
+            ) : (
+              <p>Thought for {duration} seconds</p>
+            )}
+            <ChevronDownIcon
+              className={cn(
+                'size-4 text-muted-foreground transition-transform',
+                isOpen ? 'rotate-180' : 'rotate-0',
+              )}
+            />
+          </>
+        )}
+      </CollapsibleTrigger>
+    );
+  },
+);
+
+export type ReasoningContentProps = ComponentProps<
+  typeof CollapsibleContent
+> & {
+  children: string;
+};
+
+export const ReasoningContent = memo(
+  ({ className, children, ...props }: ReasoningContentProps) => (
+    <CollapsibleContent
+      className={cn(
+        'mt-4 text-sm',
+        'data-[state=closed]:fade-out-0 data-[state=closed]:slide-out-to-top-2 data-[state=open]:slide-in-from-top-2 text-popover-foreground outline-none data-[state=closed]:animate-out data-[state=open]:animate-in',
+        className,
+      )}
+      {...props}
+    >
+      <Response className="grid gap-2">{children}</Response>
+    </CollapsibleContent>
+  ),
+);
+
+Reasoning.displayName = 'Reasoning';
+ReasoningTrigger.displayName = 'ReasoningTrigger';
+ReasoningContent.displayName = 'ReasoningContent';