import { InvalidArgumentError } from '../error/invalid-argument-error';
import type { LanguageModelCallOptions } from './language-model-call-options';

/**
 * Validates model call options and returns a new object with normalized values.
 */
export function prepareLanguageModelCallOptions({
  maxOutputTokens,
  temperature,
  topP,
  topK,
  presencePenalty,
  frequencyPenalty,
  seed,
  stopSequences,
  reasoning,
}: LanguageModelCallOptions): LanguageModelCallOptions {
  if (maxOutputTokens != null) {
    if (!Number.isInteger(maxOutputTokens)) {
      throw new InvalidArgumentError({
        parameter: 'maxOutputTokens',
        value: maxOutputTokens,
        message: 'maxOutputTokens must be an integer',
      });
    }

    if (maxOutputTokens < 1) {
      throw new InvalidArgumentError({
        parameter: 'maxOutputTokens',
        value: maxOutputTokens,
        message: 'maxOutputTokens must be >= 1',
      });
    }
  }

  if (seed != null) {
    if (!Number.isInteger(seed)) {
      throw new InvalidArgumentError({
        parameter: 'seed',
        value: seed,
        message: 'seed must be an integer',
      });
    }
  }

  return {
    maxOutputTokens,
    temperature,
    topP,
    topK,
    presencePenalty,
    frequencyPenalty,
    stopSequences,
    seed,
    reasoning,
  };
}