log_history.ts

import { setPreDebugLogHook } from './debug.js';

/**
 * LogHistory is a utility class that provides the ability to store and manage debug logs.
 * It can be enabled to record logs along with their timestamps, retrieve a specified number
 * of recent logs, or clear stored logs based on a given count. This can be useful for debugging
 * purposes, monitoring application activities, and maintaining log history.
 */
export class LogHistory {
  private logs: any[][] = [];

  /**
   * Enables the logging of debug messages with timestamps.
   * Hooks into the pre-debug log and stores each log entry along with its timestamp in the logs array.
   */
  public enable() {
    setPreDebugLogHook((...args: any[]) => {
      this.logs.push([new Date().toISOString(), ...args]);
    });
  }

  /**
   * Retrieves a specified number of logs from the end of the log history or all logs if no argument is provided.
   * The logs are ordered chronologically, with the oldest logs at the beginning of the array.
   *
   * @param last - Optional number representing the amount of recent logs to return. Defaults to 0, which returns all logs.
   * @returns An array of log arrays, each containing a timestamp and log arguments.
   */
  public getLogs(last = 0) {
    return last ? this.logs.slice(-last) : this.logs;
  }

  /**
   * Clear a specified number of logs from the beginning of the logs array.
   * If no count is provided, it will clear all logs.
   *
   * @param count - The number of logs to be removed (default: total logs length).
   */
  public clear(count = this.logs.length) {
    this.logs = this.logs.slice(count);
  }
}

export const logHistory = new LogHistory();