import { Path, resolve } from '@angular-devkit/core';
import { Tree } from '@angular-devkit/schematics';
import { isNil } from '@ibm-wch-sdk/utils';
import { readFileSync } from 'fs';
import { join } from 'path';

const PACKAGE_JSON = '/package.json' as Path;
const FALLBACK = '/data' as Path;

const OPTIONS = '.wchtoolsoptions.json' as Path;

const SDK_IMPORT = '@ibm-wch-sdk/ng';
const CLI_IMPORT = '@ibm-wch-sdk/cli';

function _findBuildVersion(): string {
  // read the file
  const pkg = JSON.parse(
    readFileSync(join(__dirname, '..', '..', 'package.json'), {
      encoding: 'utf-8'
    })
  );
  return pkg.version;
}

export function findSdkVersion(host: Tree): string {
  // try to locate the package json
  const buf = host.read(PACKAGE_JSON);
  if (isNil(buf)) {
    return _findBuildVersion();
  }

  const pkg = JSON.parse(buf.toString());
  // check if we have imports
  const deps = pkg.dependencies || {};
  const devDeps = pkg.devDependencies || {};

  return deps[SDK_IMPORT] || devDeps[CLI_IMPORT] || _findBuildVersion();
}

export function findDataDir(host: Tree): Path {
  const buf = host.read(PACKAGE_JSON);
  if (isNil(buf)) {
    return FALLBACK;
  }

  const pkg = JSON.parse(buf.toString());
  const cfg = pkg.config || {};

  const data = cfg.data || FALLBACK;

  return resolve('/' as Path, data);
}

export function findWchToolsOptions(host: Tree): Path {
  return resolve(findDataDir(host), OPTIONS);
}