import chalk from "chalk";
import type { ReadonlyRecord } from "complete-common";
import { getEnumValues } from "complete-common";
import { commandExists, PackageManager } from "complete-node";
import { DEFAULT_PACKAGE_MANAGER } from "../../constants.js";
import { promptError } from "../../prompt.js";

const PACKAGE_MANAGERS = getEnumValues(PackageManager);

export async function getPackageManagerUsedForNewProject(
  options: ReadonlyRecord<PackageManager, boolean>,
): Promise<PackageManager> {
  // If the package manager was explicitly specified in the options, use that.
  const packageManagerFromOptions = await getPackageManagerFromOptions(options);
  if (packageManagerFromOptions !== undefined) {
    return packageManagerFromOptions;
  }

  return DEFAULT_PACKAGE_MANAGER;
}

async function getPackageManagerFromOptions(
  options: ReadonlyRecord<PackageManager, boolean>,
) {
  for (const packageManager of PACKAGE_MANAGERS) {
    if (!options[packageManager]) {
      continue;
    }

    // Only one package manager flag will be specified at a time.
    // eslint-disable-next-line no-await-in-loop
    const exists = await commandExists(packageManager);
    if (!exists) {
      promptError(
        `You specified the "--${packageManager}" option, but "${chalk.green(
          packageManager,
        )}" does not seem to be a valid command.`,
      );
    }

    return packageManager;
  }

  return undefined;
}