import { LibraryJsonSchema } from '@allianz/taly-core/schemas';
import { assertValidName } from '@allianz/taly-sdk';
import { generateFiles, joinPathFragments, readProjectConfiguration, Tree } from '@nx/devkit';
import * as strings from '@nx/devkit/src/utils/string-utils';
import { extractLibraryData } from '../utils/extract-library-data';
import { BuildingBlockExampleGeneratorSchema } from './schema';

interface AddExampleOptionsWithPrefixedNameAndBuildingBlock
  extends Required<BuildingBlockExampleGeneratorSchema>,
    LibraryJsonSchema {
  nameWithPrefix: string;
  buildingBlockWithPrefix: string;
  path: string;
}

export default function generate(tree: Tree, options: BuildingBlockExampleGeneratorSchema) {
  assertValidName(options.name);

  const projectRoot = readProjectConfiguration(tree, options.project).root;
  const libraryData = extractLibraryData(tree, projectRoot);

  const nameWithPrefix = strings.dasherize(`${libraryData.prefix}-${options.name}`);
  const buildingBlockWithPrefix = strings.dasherize(
    `${libraryData.prefix}-${options.buildingBlock}`
  );

  const addExampleOptionsWithPrefixedNameAndBuildingBlock: AddExampleOptionsWithPrefixedNameAndBuildingBlock =
    {
      ...options,
      ...libraryData,
      nameWithPrefix,
      buildingBlockWithPrefix,
      path: projectRoot
    };

  addExample(tree, addExampleOptionsWithPrefixedNameAndBuildingBlock);
  updateMdFile(tree, addExampleOptionsWithPrefixedNameAndBuildingBlock);
  updateExportIndexFile(tree, addExampleOptionsWithPrefixedNameAndBuildingBlock);
}

function addExample(tree: Tree, options: AddExampleOptionsWithPrefixedNameAndBuildingBlock) {
  const templateOptions = {
    ...strings,
    ...options
  };

  generateFiles(tree, joinPathFragments(__dirname, 'files'), options.path, templateOptions);
}

function updateExportIndexFile(
  tree: Tree,
  options: AddExampleOptionsWithPrefixedNameAndBuildingBlock
) {
  const exportComponent = `export * from './${strings.dasherize(
    options.nameWithPrefix
  )}/${strings.dasherize(options.nameWithPrefix)}.component';`;

  const exportModule = `export * from './${strings.dasherize(
    options.nameWithPrefix
  )}/${strings.dasherize(options.nameWithPrefix)}.module';`;

  const exportForDoc = exportComponent + '\n' + exportModule;

  const docIndexFilePath = `${options.path}/documentation/examples/src/index.ts`;

  if (false === tree.exists(docIndexFilePath)) {
    throw new Error(`
        Could not find expected index.ts file to export the new example for the Building Block from!
        To add an example to your library there needs to be a file
        "/documentation/examples/src/index.ts" in the given path "${options.path}".
        Please check the path and make sure that the "${docIndexFilePath}"
        exists and then run this command again.
        `);
  }

  writeToFile(tree, docIndexFilePath, exportForDoc);

  return tree;
}

function updateMdFile(tree: Tree, options: AddExampleOptionsWithPrefixedNameAndBuildingBlock) {
  const exportComponent =
    '\n' + `<!-- example(${strings.dasherize(options.nameWithPrefix)}) -->` + '\n';

  const mdFilePath = `${options.path}/src/lib/${strings.dasherize(
    options.buildingBlockWithPrefix
  )}/${strings.dasherize(options.buildingBlockWithPrefix)}.md`;

  if (false === tree.exists(mdFilePath)) {
    throw new Error(`
          Could not find expected ${strings.dasherize(
            options.buildingBlockWithPrefix
          )}.md file to add the new example for the Building Block!
          To add an example to your library there needs to be a file
          "/src/lib/${strings.dasherize(options.buildingBlockWithPrefix)}/${strings.dasherize(
      options.buildingBlockWithPrefix
    )}.md"
          in the given path "${options.path}".
          Please check the path and make sure that the
          "${mdFilePath}"
          exists and then run this command again.
          `);
  }

  writeToFile(tree, mdFilePath, exportComponent);

  return tree;
}

function writeToFile(tree: Tree, path: string, newContent: string) {
  if (!tree.exists(path)) {
    return;
  }
  const libIndexFile = tree.read(path);
  const newLibIndexFileContent = libIndexFile + '\n' + newContent + '\n';
  tree.write(path, newLibIndexFileContent);
}