import { Observable } from "@noya-app/observable";

export type ServerScriptLogLevel = "log" | "warn" | "error";

export type ServerScriptLogEntry = {
  id: string;
  scriptId: string;
  level: ServerScriptLogLevel;
  values: unknown[];
  timestamp: number;
  origin?: string;
  target?: string;
  mode?: string;
};

export type LogManagerOptions = {
  maxEntries?: number;
};

const DEFAULT_MAX_ENTRIES = 50;

/**
 * Stores server script log entries emitted over the multiplayer channel.
 */
export class LogManager {
  logs$ = new Observable<ServerScriptLogEntry[]>([]);

  constructor(private options: LogManagerOptions = {}) {}

  append(entry: ServerScriptLogEntry) {
    this.logs$.set(this.truncate([...this.logs$.get(), entry]));
  }

  appendMany(entries: ServerScriptLogEntry[]) {
    if (entries.length === 0) return;
    this.logs$.set(this.truncate([...this.logs$.get(), ...entries]));
  }

  clear() {
    this.logs$.set([]);
  }

  private truncate(entries: ServerScriptLogEntry[]) {
    const limit = this.options.maxEntries ?? DEFAULT_MAX_ENTRIES;
    if (limit <= 0) return entries;
    return entries.slice(-limit);
  }
}