import { SUPPORTED_CONTRACT_VERSIONS } from '../../manifest/contracts';
import type { Check } from './types';

interface ManifestWithContract {
  celilo_contract?: string;
}

/**
 * Compares the manifest's declared `celilo_contract` against the framework's
 * supported set:
 *
 * - `ok`   — claim equals the latest supported contract.
 * - `warn` — claim is older but still supported. The manifest works, but
 *            new contract features won't be available.
 * - `fail` — claim is unknown to the framework (typo, future version
 *            from a newer celilo, etc.). Manifest schema validation
 *            already catches this case more loudly; we still report it
 *            so a `module check` against a manifest with a bad contract
 *            highlights it as a contract-level problem.
 *
 * Today the framework only ships contract "1.0", so the warn branch is
 * forward-looking; once "1.1" lands, modules still on "1.0" will see a
 * minor-bump suggestion.
 */
export function checkContractVersion(manifest: ManifestWithContract): Check {
  const claimed = manifest.celilo_contract;
  const supported = SUPPORTED_CONTRACT_VERSIONS;
  const latest = supported[supported.length - 1];

  if (!claimed) {
    return {
      category: 'contract_version',
      name: 'celilo_contract',
      status: 'fail',
      message: 'manifest is missing the celilo_contract field',
      suggestedValue: latest,
    };
  }

  if (claimed === latest) {
    return {
      category: 'contract_version',
      name: 'celilo_contract',
      status: 'ok',
      message: `manifest declares celilo_contract: ${claimed} (latest)`,
      currentValue: claimed,
    };
  }

  if ((supported as readonly string[]).includes(claimed)) {
    return {
      category: 'contract_version',
      name: 'celilo_contract',
      status: 'warn',
      message: `manifest declares celilo_contract: ${claimed} (still supported, but ${latest} is available)`,
      currentValue: claimed,
      suggestedValue: latest,
    };
  }

  return {
    category: 'contract_version',
    name: 'celilo_contract',
    status: 'fail',
    message: `manifest declares celilo_contract: ${claimed} (unknown to this framework — supported: ${supported.join(', ')})`,
    currentValue: claimed,
    suggestedValue: latest,
  };
}