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import { useRef, useState, useEffect } from "react";
import { generateGruvboxFromString } from "./utils/generate_gruvbox";
import "./App.css";
function App() {
const [socket, setSocket] = useState(null);
const [posts, setPosts] = useState([]);
const postsRef = useRef([]);
const [content, setContent] = useState("");
const [username, setUsername] = useState("");
const [error, setError] = useState("");
const [color, setColor] = useState("");
const scrollToBottomOfChat = () => {
const objDiv = document.getElementById("chat");
objDiv.scrollTop = objDiv.scrollHeight;
};
useEffect(() => {
const protocol = document.location.protocol === "https:" ? "wss:" : "ws:";
let socket;
fetch("/posts")
.then((r) => r.json())
.then((msgs) => {
postsRef.current = msgs;
setPosts(postsRef.current);
scrollToBottomOfChat();
})
.then(() => {
socket = new WebSocket(`${protocol}//${document.location.host}/`);
socket.addEventListener("open", () => {
socket.send("ping");
});
socket.addEventListener("message", (msg) => {
const { data } = msg;
if (data === "pong") return;
const chat = JSON.parse(msg.data);
if (chat.author) {
postsRef.current = [...postsRef.current, chat];
setPosts(postsRef.current);
scrollToBottomOfChat();
}
});
setSocket(socket);
});
return () => {
socket.close();
};
}, []);
useEffect(() => {
setColor(generateGruvboxFromString(username));
}, [username]);
const addPost = () => {
setError("");
if (socket) {
fetch("/posts", {
method: "POST",
headers: { Content: "application/json" },
body: JSON.stringify({ author: username, message: content }),
}).then(() => setContent(""));
}
};
return (
<div className="container" style={{ border: `1px solid ${color}` }}>
<div style={{ textAlign: "center" }}>
<h2>TrongELISPosting</h2>
</div>
<div id="chat" className="chat">
<p>Welcome!</p>
{posts.map((post) => (
<div
key={post.id}
style={{
lineBreak: "normal",
display: "flex",
alignItems: "center",
justifyContent: "space-between",
}}
>
<div>
<span style={{ color: generateGruvboxFromString(post.author) }}>
{post.author}:{" "}
</span>
<span>{post.message}</span>
</div>
<div style={{ fontSize: "x-small" }}>
[{new Date(post.date).toLocaleString()}]
</div>
</div>
))}
</div>
<div>
<input
placeholder={"Username"}
className="input"
style={{ color }}
onChange={(e) => {
setUsername(e.target.value);
}}
value={username}
></input>
<textarea
placeholder={"Message"}
className="input"
onChange={(e) => setContent(e.target.value)}
value={content}
rows={1}
cols={40}
></textarea>
<div className="button" onClick={addPost}>
Post
</div>
{error ? <p style={{ color: "red" }}>{error}</p> : null}
</div>
</div>
);
}
export default App;
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