import {
  Tree,
  installPackagesTask,
  joinPathFragments,
  logger,
  readJson,
  workspaceLayout
} from '@nx/devkit';
import { LibraryGeneratorSchema } from './schema';
import { addBbDependenciesToLibrary } from './updaters/add-library-dependencies/add-library-dependencies';
import { addProjectConfig } from './updaters/add-project-config/add-project-config';
import { addTemplates } from './updaters/add-templates/add-templates';
import { addWorkspaceDependencies } from './updaters/add-workspace-dependencies/add-workspace-dependencies';
import { updateBaseTsconfigJson } from './updaters/update-base-tsconfig-json/update-base-tsconfig-json';
import { updateGitignore } from './updaters/update-gitignore/update-gitignore';
import { updatePackageJson } from './updaters/update-package-json/update-package-json';

export interface ProjectDetails {
  projectName: string;
  projectRoot: string;
}

export interface ExpandedLibraryGeneratorSchema extends Omit<LibraryGeneratorSchema, 'name'> {
  projectName: string;
  projectRoot: string;
}

function getExpandedOptions(options: LibraryGeneratorSchema): ExpandedLibraryGeneratorSchema {
  // extract a name from the given library name that we can use as a
  // folder name, e.g. "@allianz/my-library" -> "my-library"
  const projectDirectoryName = options.name.includes('/')
    ? options.name.substring(options.name.indexOf('/') + 1)
    : options.name;

  const projectRoot = joinPathFragments(workspaceLayout().libsDir, projectDirectoryName);

  return {
    projectName: options.name,
    projectRoot,
    category: options.category,
    prefix: options.prefix
  };
}

function verifyWorkspaceSetup(tree: Tree) {
  const packageJsonPath = '/package.json';
  if (!tree.exists(packageJsonPath)) {
    throw new Error(
      `Cannot read package.json. Please take a look at the TALY documentation to learn more about the workspace setup: https://taly.frameworks.allianz.io/additional-documentation/getting-started.html`
    );
  }

  const packageJson = readJson(tree, packageJsonPath);
  const dependencies = [
    ...Object.keys(packageJson.dependencies || []),
    ...Object.keys(packageJson.devDependencies || [])
  ];

  // The following dependencies are required for the library generation and
  // will be automatically added when the Nx angular-monorepo preset is used.
  // If a dependency is missing, this is an indicator that the Nx workspace
  // is set up incorrectly.
  const includesRequiredDependencies =
    dependencies.includes('@angular-devkit/core') &&
    dependencies.includes('@angular-devkit/schematics') &&
    dependencies.includes('@nx/angular');
  const baseTsconfigJsonExists = tree.exists('tsconfig.base.json');
  if (!includesRequiredDependencies || !baseTsconfigJsonExists) {
    throw new Error(
      'The workspace does not fulfill the necessary prerequisites. Please take a look at the TALY documentation to learn more about the workspace setup: https://taly.frameworks.allianz.io/additional-documentation/getting-started.html'
    );
  }
}

export default async function library(tree: Tree, options: LibraryGeneratorSchema) {
  const expandedOptions = getExpandedOptions(options);
  const projectDetails = {
    projectName: expandedOptions.projectName,
    projectRoot: expandedOptions.projectRoot
  };

  verifyWorkspaceSetup(tree);

  addTemplates(tree, expandedOptions);
  addBbDependenciesToLibrary(tree, expandedOptions);
  await addProjectConfig(tree, expandedOptions);
  updatePackageJson(tree, projectDetails);
  updateBaseTsconfigJson(tree, projectDetails);
  updateGitignore(tree);
  addWorkspaceDependencies(tree);

  return () => {
    // Nx sets npm_config_legacy_peer_deps = true by default inside the `installPackagesTask` (https://github.com/nrwl/nx/blob/5ded713c3c487bd28874e75b1623ece07a79d91d/packages/nx/src/utils/package-manager.ts#L130)
    // We have to explicitly set it to prevent the default behavior
    process.env['npm_config_legacy_peer_deps'] ??= 'false';
    installPackagesTask(tree, true);

    logger.warn(
      'This command updated your workspace dependencies. Please review them to ensure they are compatible with your project.'
    );
  };
}