import { useEffect, useRef } from "react";
import { Terminal } from "@xterm/xterm";
import { WebglAddon } from "@xterm/addon-webgl";
import { SearchAddon } from "@xterm/addon-search";
import { attachSurface, detachSurface, sendInput, resizeSurface } from "./socketBridge";
import { registerSearch, unregisterSearch } from "./searchRegistry";

const decoder = new TextDecoder();
const encoder = new TextEncoder();

export function TerminalView({ surfaceId }: { surfaceId: string }) {
  const ref = useRef<HTMLDivElement>(null);

  useEffect(() => {
    if (!ref.current) return;
    const term = new Terminal({ fontFamily: "'JetBrains Mono Variable', 'JetBrains Mono', monospace", fontSize: 13, convertEol: false, scrollback: 10000 });
    try {
      term.loadAddon(new WebglAddon());
    } catch {
      // webgl unavailable → fall back to canvas/dom renderer silently
    }
    term.open(ref.current);

    const search = new SearchAddon();
    term.loadAddon(search);
    registerSearch(surfaceId, search);

    // Input → daemon.
    const inputDisposable = term.onData((data) => {
      void sendInput(surfaceId, encoder.encode(data));
    });

    let disposed = false;

    // Attach: fresh xterm instance, write snapshot, then stream live output.
    void attachSurface(surfaceId, (bytes) => {
      if (!disposed) term.write(decoder.decode(bytes));
    }).then((res) => {
      if (disposed) return;
      if (res.snapshot) term.write(res.snapshot);
      if (res.cols && res.rows) {
        term.resize(res.cols, res.rows);
        void resizeSurface(surfaceId, res.cols, res.rows);
      }
    });

    return () => {
      disposed = true;
      inputDisposable.dispose();
      void detachSurface(surfaceId);
      unregisterSearch(surfaceId);
      term.dispose();
    };
  }, [surfaceId]);

  return <div ref={ref} style={{ width: "100%", height: "100%" }} />;
}
