subathon-timer/timer.js

window.addEventListener("DOMContentLoaded", () => {
  const websocket = new ReconnectingWebSocket("wss://lilac.thewisewolf.dev/tracker/timer/ws");
  communicate(websocket);
});


class Timer {
  constructor(renderer, timer_data) {
    this.renderer = renderer;
    this.destroying = false;

    this.update_from_data(timer_data);
  }

  update_from_data(timer_data) {
    this.end_at = new Date(timer_data.end_at);
    this.running = timer_data.is_running;
    this.name = timer_data.name;
    this.score_table = timer_data.score_table;

    this.total_contribution = timer_data.total_contribution;
    this.total_subpoints = timer_data.total_subpoints;
    this.total_bits = timer_data.total_bits;

    this.goals_met = timer_data.goals_met;
    this.goals_total = timer_data.goals_total;
    this.last_goal = timer_data.last_goal;
    this.next_goal = timer_data.next_goal;
    this.goals = timer_data.goals;

    this.last_contribution = timer_data.last_contribution;
    this.leaderboard = timer_data.leaderboard;
  }

  render_time() {
    this.renderer.render_time(
      Math.floor((this.end_at - new Date()) / 1000)
    );
  }

  render() {
    // Render goal
    if (this.next_goal != null) {
      this.renderer.render_current_goal(
        this.next_goal.name,
        this.total_contribution,
        this.next_goal.required,
      );
    } else if (this.last_goal != null) {
      this.renderer.render_current_goal(
        this.last_goal.name,
        this.total_contribution,
        this.last_goal.required,
      );
    } else {
      this.renderer.clear_current_goal();
    }

    // Render leaderboard 
    this.renderer.render_users(this.leaderboard);

    // Render timer 
    this.render_time();
  }

  /**
   * Recursive call run per second to update the rendered timer
   */
  tick() {
    if (!this.destroying) {
      this.render_time();

      if (this.running) {
        setTimeout(this.tick.bind(this), 1000);
      }
    }

  }
}

class TimerRenderer {
  constructor() {
    // HH:MM or MM:SS
    this.timer = document.getElementById("Timer");

    // Current Goal:
    this.goal_label = document.getElementById("GoalLabel")

    // Name of the goal to display
    this.goal_name = document.getElementById("GoalName")

    // 1524/3000 Points
    this.goal_progress = document.getElementById("GoalProgress")

    // Top 3 Gifters 
    this.topusers_label = document.getElementById("TopUsers")

    // Leaderboard items 
    // 1. (or points?)
    this.topusers_user1_num = document.getElementById("GiftUserNum1")
    // Name of user 1
    this.topusers_user1_name = document.getElementById("GiftUserName1")
    this.topusers_user2_num = document.getElementById("GiftUserNum2")
    this.topusers_user2_name = document.getElementById("GiftUserName2")
    this.topusers_user3_num = document.getElementById("GiftUserNum3")
    this.topusers_user3_name = document.getElementById("GiftUserName3")
  }

  /**
   * Bring the display into a standard initial state.
   */
  reset() {
    this.timer.textContent = "00:00";
    this.goal_label.textContent = "Next Goal:";
    this.goal_name.textContent = "Be awesome";
    this.goal_progress.textContent = "00/00";

    this.topusers_label.textContent = "Leaderboard:";
    this.topusers_user1_num.textContent = "1";
    this.topusers_user1_name.textContent = "Anonymous";
    this.topusers_user2_num.textContent = "2";
    this.topusers_user2_name.textContent = "Anonymous";
    this.topusers_user3_num.textContent = "3";
    this.topusers_user3_name.textContent = "Anonymous";

  }

  /**
   * Render the timer from a time remaining.
   *
   * @param {integer} seconds_remaining - The number of seconds remaining on the timer.
   */
  render_time(seconds_remaining) {
    var timestr;
    // Render a time remaining given in seconds
    if (seconds_remaining <= 0) {
      timestr = "00:00";
    } else {
      var seconds = seconds_remaining % 60;
      seconds_remaining = seconds_remaining - seconds;
      var minutes = Math.floor(seconds_remaining / 60);
      var hours = Math.floor(minutes / 60);
      minutes = minutes - 60 * hours;

      // Change rendering mode based on hours or minutes left
      if (hours > 0) {
        timestr = String(hours).padStart(2, '0') + ':' + String(minutes).padStart(2, '0');
      } else {
        timestr = String(minutes).padStart(2, '0') + ':' + String(seconds).padStart(2, '0');
      }
    }
    this.timer.textContent = timestr;
  }

  /**
    * Render the current goal. 
    *
    * @param {string} name     - The name of the current goal.
    * @param {number} current  - The number of points we currently have.
    * @param {number} required - The number of points to achieve the goal.
    */
  render_current_goal(name, current, required) {
    // TODO: Some kind of end condition, ability to clear a goal etc
    // E.g. if subathon doesn't have a goal at all 
    // Or after we accomplish all goals

    this.goal_name.textContent = name;

    // Bitwise OR done to convert floats to integers if needed
    this.goal_progress.textContent = String(current | 0) + '/' + String(required | 0)
  }

  /**
   * Clear the current goal field.
   */
  clear_current_goal() {
    this.goal_name.textContent = "";
    this.goal_progress.textContent = "";
    this.goal_label.textContent = "";
  }

  /**
    * Render the user leaderboard.
    *
    * @param {Object[]} users               - The user leaderboard in descending (points, name) order.
    * @param {integer}  users[].amount      - The number of points this users has contrib.
    * @param {string}   users[].user_name   - The name of this user.
    */
  render_users(users) {

    if (users.length >= 1) {
      this.topusers_user1_num.textContent = "1";
      this.topusers_user1_name.textContent = users[0].user_name;
    } else {
      this.topusers_user1_num.textContent = "";
      this.topusers_user1_name.textContent = "";
    }

    if (users.length >= 2) {
      this.topusers_user2_num.textContent = "2";
      this.topusers_user2_name.textContent = users[1].user_name;
    } else {
      this.topusers_user2_num.textContent = "";
      this.topusers_user2_name.textContent = "";
    }

    if (users.length >= 3) {
      this.topusers_user3_num.textContent = "3";
      this.topusers_user3_name.textContent = users[2].user_name;
    } else {
      this.topusers_user3_num.textContent = "";
      this.topusers_user3_name.textContent = "";
    }

  }

}

class ReconnectingWebSocket {
  constructor(url) {
    this.url = url;
    this.ws = null;
    this.attempt = 0;
    this.connect();

    this.closing = false;
    this.onopen = null;
    this.onmessage = null;
    this.onclose = null;
    this.onerror = null;
  }

  connect() {
    this.ws = new WebSocket(this.url);

    this.ws.onopen = () => {
      console.log('WebSocket connected');
      this.attempt = 0;
      if (this.onopen != null) {
        this.onopen();
      }
    };

    this.ws.onmessage = (msg) => {
      console.log('Received:', msg.data);
      if (this.onmessage != null) {
        this.onmessage(msg);
      }
    };

    this.ws.onclose = () => {
      if (this.closing) {
        console.log('Closing Websocket.')
      } {
        console.warn('WebSocket closed. Reconnecting...');
        this.reconnect();
      }
    };

    this.ws.onerror = (err) => {
      console.error('WebSocket error:', err);
      if (this.onerror != null) {
        this.onerror();
      }
      this.close();
    };
  }

  reconnect() {
    const delay = this.getBackoffDelay(this.attempt);
    console.log(`Reconnecting in ${delay}ms`);

    setTimeout(() => {
      this.attempt++;
      this.connect();
    }, delay);
  }

  close() {
    this.closing = true;
    this.ws.close();
    if (this.onclose != null) {
      this.onclose();
    }
  }

  getBackoffDelay(attempt) {
    const base = 500; // 0.5 second
    const max = 30000; // 30 seconds
    const jitter = Math.random() * 1000;
    return Math.min(base * 2 ** attempt + jitter, max);
  }

  send(data) {
    if (this.ws.readyState === WebSocket.OPEN) {
      this.ws.send(data);
    } else {
      console.warn('WebSocket not connected');
    }
  }
}




function communicate(websocket) {
  console.log("Communicating");
  const params = new URLSearchParams(window.location.search);
  var renderer = new TimerRenderer();
  let timer;

  websocket.onopen = () => {
    websocket.send(
      JSON.stringify(
        {
          type: "init",
          channel: "SubTimer",
          community: params.get('community')
        }
      )
    );
    renderer.reset();
  };

  websocket.onmessage = ({ data }) => {
    const event = JSON.parse(data);
    switch (event.type) {
      case "DO":
        let args = event.args;

        // Call the specified method
        switch (event.method) {
          case "setTimer":
            if (timer == null) {
              timer = new Timer(renderer, args);
            } else {
              timer.update_from_data(args);
            }
            timer.render();
            timer.tick();
            break;
          case "noTimer":
            if (timer != null) {
              timer.destroying = true;
              timer = null;
            }
            renderer.reset();
          case "endTimer":
            if (timer != null) {
              timer.destroying = true;
              timer = null;
            }
          default:
            throw new Error(`Unsupported method requested: ${event.method}.`)
        }
        break;
      default:
        throw new Error(`Unsupported event type: ${event.type}.`);
    }
  };
}