export class ArgParser<T extends Record<string, string[]>> {
  private args: string[];
  private flags: Map<keyof T, boolean> = new Map();

  constructor(args: string[]) {
    this.args = args;
  }

  public get(key: string) {
    const index = this.args.indexOf(key);
    if (index === -1) return null;
    return this.args[index + 1];
  }

  setFlagDefs(flagDefs: T) {
    for (const [flag, defs] of Object.entries(flagDefs)) {
      for (const def of defs) {
        if (this.argFlags.includes(def)) {
          this.flags.set(flag, true);
        }
      }
    }
    return this;
  }

  getFlag(flag: keyof T) {
    return this.flags.get(flag);
  }

  get argFlags() {
    return this.args.filter((arg) => arg.startsWith("-"));
  }

  get nonFlags() {
    return this.args.filter((arg) => !arg.startsWith("-"));
  }

  get namedArgs() {
    return this.args.filter((arg) => arg.startsWith("--"));
  }

  get task() {
    return this.nonFlags[0];
  }
  get taskArgs() {
    return this.nonFlags.slice(1);
  }

  static parse(args: string[]) {
    return new ArgParser(args);
  }
}