Files
kandev/apps/web/components/task/chat/chat-motion.tsx
T

88 lines
2.4 KiB
TypeScript

"use client";
import {
createContext,
useContext,
useLayoutEffect,
useMemo,
useRef,
useState,
type ReactNode,
} from "react";
import { useChatMotion } from "@/hooks/use-chat-motion";
import { getNewArrivalIds, type ArrivalSnapshot } from "./chat-motion-state";
const ChatMotionContext = createContext({
live: false,
arrivals: new Set<string>() as ReadonlySet<string>,
receivedAt: 0,
});
export function ChatMotionProvider({
children,
sessionId,
messages,
live: eligible,
}: {
children: ReactNode;
sessionId: string | null;
messages: readonly { id: string }[];
live: boolean;
}) {
const enabled = useChatMotion();
const live = eligible && enabled;
const identity = messages.map((message) => message.id).join("\0");
const ids = useMemo(() => (identity ? identity.split("\0") : []), [identity]);
const previous = useRef<ArrivalSnapshot | null>(null);
const snapshot = useMemo(() => ({ sessionId, ids, live }), [sessionId, ids, live]);
const value = useMemo(
() => ({
live,
arrivals: getNewArrivalIds(previous.current, snapshot),
receivedAt: Date.now(),
}),
[live, snapshot],
);
useLayoutEffect(() => {
previous.current = snapshot;
}, [snapshot]);
return <ChatMotionContext.Provider value={value}>{children}</ChatMotionContext.Provider>;
}
export function useChatTextMotion(): boolean {
return useContext(ChatMotionContext).live;
}
/** The inner wrapper leaves measured row geometry and message identity intact. */
export function ChatMotionItem({
children,
messageId,
}: {
children: ReactNode;
messageId: string;
}) {
const context = useContext(ChatMotionContext);
const [arrival] = useState(() => (context.arrivals.has(messageId) ? context.receivedAt : null));
const played = useRef(false);
const ref = useRef<HTMLDivElement>(null);
useLayoutEffect(() => {
if (!context.live || arrival === null || played.current) return;
played.current = true;
const remaining = 160 - (Date.now() - arrival);
if (remaining <= 0 || !ref.current?.animate) return;
const animation = ref.current.animate(
[
{ opacity: 0, transform: "translateY(3px)" },
{ opacity: 1, transform: "translateY(0)" },
],
{ duration: remaining, easing: "ease-out" },
);
return () => animation.cancel();
}, [arrival, context.live]);
return (
<div ref={ref} data-chat-motion-item={messageId}>
{children}
</div>
);
}