import fs from 'fs-extra';
import watch from 'node-watch';
import path from 'path';

import { buildRepository } from './repository/build';

/**
 * Create a filesystem watch task for a repository directory
 * Equivalent to tsc -w
 * @param location Repository path
 * @param out Create output files. False - dry run.
 * @param doDeploy Use deployment after build success
 */
export async function watchRepository(
  location?: string,
  out = true,
  doDeploy?: string): Promise<void> {

  if (!location) {
    location = process.cwd();
  }

  const buildMetaFile = path.join(location, 'squeebot.repo.json');
  if (!await fs.pathExists(buildMetaFile)) {
    throw new Error(`${location} is not a valid squeebot repository development environment!`);
  }

  const meta = await fs.readJson(buildMetaFile);
  if (!meta.name) {
    throw new Error(`${location} is not a valid squeebot repository development environment!`);
  }

  console.log('Watching repository "%s"!', meta.name);

  watch(location, {
    recursive: true,
    filter(f, skip): any {
      if (/\/node_modules/.test(f) ||
          /\.out/.test(f) ||
          /\.git/.test(f) ||
          /\.json$/.test(f)) {
        return skip;
      }

      if (meta.typescript && /\.js$/.test(f)) {
        return skip;
      }

      return true;
    },
  }, (evt, f) => {
    console.log(`\n ==> ${f} changed, rebuilding...`);
    buildRepository(location, out, doDeploy).catch((e) => {
      console.error(e);
    });
  });
}