/*
 * Licensed to Elasticsearch B.V. under one or more contributor
 * license agreements. See the NOTICE file distributed with
 * this work for additional information regarding copyright
 * ownership. Elasticsearch B.V. licenses this file to you under
 * the Apache License, Version 2.0 (the "License"); you may
 * not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

const chalk = require('chalk');
const { resolve } = require('path');
const Generator = require('yeoman-generator');
const utils = require('../utils');

const DOCUMENTATION_PAGE_PATH = resolve(__dirname, '../../doc_site/src/views');

module.exports = class extends Generator {
  constructor(args, options) {
    super(args, options);

    this.fileType = options.fileType;
  }

  prompting() {
    const prompts = [
      {
        message: "What's the name of the component you're documenting? Use snake_case, please.",
        name: 'name',
        type: 'input',
        store: true,
      },
    ];

    if (this.fileType === 'demo') {
      prompts.push({
        message: `What's the name of the directory this demo should go in? (Within ${DOCUMENTATION_PAGE_PATH}). Use snake_case, please.`,
        name: 'folderName',
        type: 'input',
        store: true,
        default: (answers) => answers.name,
      });

      prompts.push({
        message: 'What would you like to name this demo? Use snake_case, please.',
        name: 'demoName',
        type: 'input',
        store: true,
      });
    }

    return this.prompt(prompts).then((answers) => {
      this.config = answers;
    });
  }

  writing() {
    const config = this.config;

    const writeDocumentationPage = () => {
      const componentExampleName = utils.makeComponentName(config.name, false);
      const componentExamplePrefix = utils.lowerCaseFirstLetter(componentExampleName);
      const fileName = config.name;

      const path = DOCUMENTATION_PAGE_PATH;

      const vars = (config.documentationVars = {
        componentExampleName,
        componentExamplePrefix,
        fileName,
      });

      const documentationPagePath = (config.documentationPagePath = `${path}/${config.name}/${config.name}_example.js`);

      this.fs.copyTpl(
        this.templatePath('documentation_page.js'),
        this.destinationPath(documentationPagePath),
        vars
      );
    };

    const writeDocumentationPageDemo = (fileName, folderName) => {
      const componentExampleName = utils.makeComponentName(fileName, false);
      const componentExamplePrefix = utils.lowerCaseFirstLetter(componentExampleName);
      const componentName = utils.makeComponentName(config.name);

      const path = DOCUMENTATION_PAGE_PATH;

      const vars = (config.documentationVars = {
        componentExampleName,
        componentExamplePrefix,
        componentName,
        fileName,
      });

      const documentationPageDemoPath = (config.documentationPageDemoPath = `${path}/${folderName}/${fileName}.js`);

      this.fs.copyTpl(
        this.templatePath('documentation_page_demo.js'),
        this.destinationPath(documentationPageDemoPath),
        vars
      );
    };

    const writeSandbox = () => {
      const fileName = config.name;
      const componentExampleName = utils.makeComponentName(fileName, false);

      const path = DOCUMENTATION_PAGE_PATH;

      const vars = (config.documentationVars = {
        componentExampleName,
        fileName,
      });

      const sandboxPath = (config.documentationPageDemoPath = `${path}/${config.name}/${fileName}`);

      this.fs.copyTpl(
        this.templatePath('documentation_sandbox.html'),
        this.destinationPath(`${sandboxPath}_sandbox.html`)
      );

      this.fs.copyTpl(
        this.templatePath('documentation_sandbox.js'),
        this.destinationPath(`${sandboxPath}_sandbox.js`),
        vars
      );
    };

    switch (this.fileType) {
      case 'documentation':
        writeDocumentationPage();
        writeDocumentationPageDemo(config.name, config.name);
        break;

      case 'demo':
        writeDocumentationPageDemo(config.demoName, config.folderName);
        break;

      case 'sandbox':
        writeSandbox();
        break;
    }
  }

  end() {
    const showImportDemoSnippet = () => {
      const {
        componentExampleName,
        componentExamplePrefix,
        fileName,
      } = this.config.documentationVars;

      this.log(chalk.white('\n// Import demo into example.'));
      this.log(
        `${chalk.magenta('import')} ${componentExampleName} from ${chalk.cyan(
          `'./${fileName}'`
        )};\n` +
          `${chalk.magenta('const')} ${componentExamplePrefix}Source = require(${chalk.cyan(
            `'!!raw-loader!./${fileName}'`
          )});\n` +
          `${chalk.magenta(
            'const'
          )} ${componentExamplePrefix}Html = renderToHtml(${componentExampleName});`
      );

      this.log(chalk.white('\n// Render demo.'));
      this.log(
        `<GuideSection\n` +
          `  title="${componentExampleName}"\n` +
          `  source={[{\n` +
          `    type: GuideSectionTypes.JS,\n` +
          `    code: ${componentExamplePrefix}Source,\n` +
          `  }, {\n` +
          `    type: GuideSectionTypes.HTML,\n` +
          `    code: ${componentExamplePrefix}Html,\n` +
          `  }]}\n` +
          `>\n` +
          `  <GuideText>\n` +
          `    Description needed: how to use the ${componentExampleName} component.\n` +
          `  </GuideText>\n` +
          `\n` +
          `  <GuideDemo>\n` +
          `    <${componentExampleName} />\n` +
          `  </GuideDemo>\n` +
          `</GuideSection>\n`
      );
    };

    const showImportRouteSnippet = (suffix, appendToRoute) => {
      const { componentExampleName, fileName } = this.config.documentationVars;

      this.log(chalk.white('\n// Import example into routes.js.'));
      this.log(
        `${chalk.magenta('import')} ${componentExampleName}${suffix}\n` +
          `  ${chalk.magenta('from')} ${chalk.cyan(
            `'../../views/${fileName}/${fileName}_${suffix.toLowerCase()}'`
          )};`
      );

      this.log(chalk.white('\n// Import route definition into routes.js.'));
      this.log(
        `{\n` +
          `  name: ${chalk.cyan(`'${componentExampleName}${appendToRoute ? suffix : ''}'`)},\n` +
          `  component: ${componentExampleName}${suffix},\n` +
          `  hasReact: ${chalk.magenta('true')},\n` +
          `}`
      );
    };

    this.log('------------------------------------------------');
    this.log(chalk.bold('Import snippets:'));

    switch (this.fileType) {
      case 'documentation':
        showImportRouteSnippet('Example');
        break;

      case 'demo':
        showImportDemoSnippet();
        break;

      case 'sandbox':
        showImportRouteSnippet('Sandbox', true);
        break;
    }
    this.log('------------------------------------------------');
  }
};