import { css, html, LitElement } from "lit";
import { customElement, property, state } from "lit/decorators.js";
import { classMap } from "lit/directives/class-map.js";

@customElement("dev-reloader")
export class DevReloader extends LitElement {
  @property({ attribute: true })
  ws = "";

  @property({ attribute: true, type: Boolean, reflect: true })
  auto = false;

  @state()
  private _connected = false;

  private _armed = false;

  private _socket?: WebSocket;

  static override styles = css`
    button {
      appearance: none;
      background: none;
      border: none;
      padding: none;
    }

    .widget {
      position: fixed;
      z-index: 999;
      bottom: 1rem;
      left: 1rem;
      border: solid 1px #0002;
      padding: 1rem;
      border-radius: 9999px;
      cursor: pointer;
      display: flex;
      align-items: center;
      box-shadow: 0 0.5rem 1rem #0002;
      opacity: 0.5;

      &:hover {
        opacity: 1;
      }
    }

    .indicator {
      width: 8px;
      height: 8px;
      border-radius: 9999px;
      background: #f60;

      &.connected {
        background: #06f;
      }
    }

    .label {
      margin-left: 1rem;
    }
  `;

  override connectedCallback() {
    super.connectedCallback();
    this._connected = true;
    this._handleDisconnect();
  }

  private _handleDisconnect() {
    if (this._connected) {
      console.log("dev-reloader: disconnected");
      this._connected = false;
      this._socket = undefined;
      const intvl = setInterval(() => {
        if (!this._socket || this._socket.readyState === WebSocket.CLOSED) {
          try {
            this._socket = new WebSocket(this.ws);
            this._socket.addEventListener("open", () => {
              if (this.auto && this._armed) {
                globalThis.location.reload();
              }
              console.log("dev-reloader: connected");
              this._connected = true;
              this._armed = true;
              clearInterval(intvl);
            });
            this._socket.addEventListener(
              "close",
              this._handleDisconnect.bind(this),
            );
            this._socket.addEventListener(
              "error",
              this._handleDisconnect.bind(this),
            );
          } catch { /* no-op */ }
        }
      }, 500);
    }
  }

  private _toggleAuto() {
    this.auto = !this.auto;
  }

  protected override render() {
    return html`
      <button type="button" class="widget" @click="${this._toggleAuto}">
        <div class="${classMap({
        indicator: true,
        connected: this._connected,
      })}"></div>
        <div class="label">
          ${this.auto ? "Disable" : "Enable"} auto-reload
        </div>
      </button>
    `;
  }
}