import { EditorState } from "prosemirror-state";
import { Command } from "../types";

export interface FailedCommandResult {
  success: false;
}

export interface SuccessCommandResult {
  success: true;
  newState: EditorState;
}

export type CommandResult = FailedCommandResult | SuccessCommandResult;

export function applyCommand(command: Command, initial: EditorState): CommandResult {
  let newState = initial;
  const success = command(initial, tr => {
    // It's important to apply the transaction to `newState` (as opposed to
    // `initial`), to allow the command to internally execute multiple commands.
    newState = newState.apply(tr);
  });
  return success ? { success, newState } : { success };
}