import type { NoirPackageConfig } from '@aztec/foundation/noir';

import TOML from '@iarna/toml';
import { CommanderError } from 'commander';
import { rename, writeFile } from 'fs/promises';

/**
 * Updates a file in place atomically.
 * @param filePath - Path to file
 * @param contents - New contents to write
 */
export async function atomicUpdateFile(filePath: string, contents: string) {
  const tmpFilepath = filePath + '.tmp';
  try {
    await writeFile(tmpFilepath, contents, {
      // let's crash if the tmp file already exists
      flag: 'wx',
    });
    await rename(tmpFilepath, filePath);
  } catch (e) {
    if (e instanceof Error && 'code' in e && e.code === 'EEXIST') {
      const commanderError = new CommanderError(
        1,
        e.code,
        `Temporary file already exists: ${tmpFilepath}. Delete this file and try again.`,
      );
      commanderError.nestedError = e.message;
      throw commanderError;
    } else {
      throw e;
    }
  }
}

/**
 * Pretty prints Nargo.toml contents to a string
 * @param config - Nargo.toml contents
 * @returns The Nargo.toml contents as a string
 */
export function prettyPrintNargoToml(config: NoirPackageConfig): string {
  const withoutDependencies = Object.fromEntries(Object.entries(config).filter(([key]) => key !== 'dependencies'));

  const partialToml = TOML.stringify(withoutDependencies);
  const dependenciesToml = Object.entries(config.dependencies).map(([name, dep]) => {
    const depToml = TOML.stringify.value(dep);
    return `${name} = ${depToml}`;
  });

  return partialToml + '\n[dependencies]\n' + dependenciesToml.join('\n') + '\n';
}