const acorn = require('acorn');
const escodegen = require('escodegen');
const replace = require('replace');
const path = require('path');
const fs = require('fs');

const reg = new RegExp(/(configs).*\]/s);
const targetPath = path.join(process.cwd(), 'hola.config.js');
/**
 * 更新`hola.config.js`中的configs参数
 * @param {object} addCode 需要新增的对象
 */
const updateHolaConfigs = (addCode: object): void => {
  let file = fs.readFileSync(targetPath, 'utf8');
  let comments = [];
  let tokens = [];
  const ast = acorn.parse(file, {
    locations: true,
    ranges: true,
    onComment: comments,
    onToken: tokens,
  });
  const addAst = getObjectAst(addCode);

  ast.body[0].expression.right.properties.forEach((item) => {
    if (item.key.name === 'configs') {
      item.value.elements = item.value.elements.concat(addAst);
    }
  });

  escodegen.attachComments(ast, comments, tokens); // 添加注释

  const decodedContent = escodegen.generate(ast, {
    format: {
      indent: {
        style: '  ',
        adjustMultilineComment: true,
      },
    },
    comment: true,
  });

  console.log('decodedContent', decodedContent);

  replace({
    regex: reg,
    replacement: decodedContent.match(reg)[0],
    paths: [targetPath],
    recursive: true,
    silent: true,
  });
};

/**
 * parse object to ast
 * @param {object} obj which object u want to parse
 */
function getObjectAst(obj: object): object {
  let properties = [] as object[];
  Object.keys(obj).forEach((key) => {
    properties.push(getPropertyAst(key, obj[key]));
  });
  return {
    type: 'ObjectExpression',
    properties: properties,
  };
}

/**
 * get a object.property ast
 * @param {string} propertyKey
 * @param {string} propertyValue
 */
function getPropertyAst(propertyKey: string, propertyValue: string): object {
  let propertyAstTemplate = {
    type: 'Property',
    method: false,
    shorthand: false,
    computed: false,
    key: { type: 'Identifier', name: propertyKey },
    value: {
      type: 'Literal',
      value: propertyValue,
      raw: propertyValue,
    },
    kind: 'init',
  };
  return propertyAstTemplate;
}

export default updateHolaConfigs;