const path = require("path");

const rootPath = path.resolve(process.cwd(), "node_modules");
/** 解析绝对路径
 * @param {Object} dir
 */
function resolvePath(dir: string) {
  return path.resolve(rootPath, dir);
}

class TransformPages {
  public CONFIG: Config = {
    includes: ["path", "aliasPath", "name"],
  };
  public pagesPath: string;
  public uniPagesJSON: UniPagesJSON;
  public routes: string[];
  public platform: string;

  /**
   * Creates an instance of TransformPages.
   * @param {Config} config 调用getPagesRoutes时,返回值保留字段
   * @param {string} pagesPath pages.json 文件相对与项目根目录的位置
   * @memberof TransformPages
   */
  constructor(config: Config, pagesPath: string) {
    config = {
      ...this.CONFIG,
      ...config,
    };
    this.CONFIG = config;
    this.pagesPath = path.resolve(process.cwd(), pagesPath);
    this.uniPagesJSON = require(resolvePath(
      "@dcloudio/uni-cli-shared/dist/json/pages.js"
    ));
    this.platform = process.env["UNI_PLATFORM"];
    this.routes = this.getPagesRoutes().concat(this.getNotMpRoutes());
  }
  /**
   * 获取所有pages.json下的内容 返回json
   */
  get pagesJson() {
    return this.uniPagesJSON.parsePagesJson(this.pagesPath, this.platform);
  }
  /**
   * 通过读取pages.json文件 生成直接可用的routes
   */

  getPagesRoutes(pages = this.pagesJson.pages, rootPath = null) {
    const routes = [];
    let route, value;
    pages.forEach((pItem, pIndex) => {
      route = {};
      value = "";
      this.CONFIG.includes.forEach((cItem, cIndex) => {
        value = pItem[cItem];
        if (cItem === "path") {
          value = rootPath ? `/${rootPath}/${value}` : `/${value}`;
        }
        if (cItem === "aliasPath" && pIndex == 0 && rootPath == null) {
          route[cItem] = route[cItem] || "/";
        } else {
          route[cItem] = value ? value : {};
        }
      });
      routes.push(route);
    });
    return routes;
  }
  /**
   * 解析小程序分包路径
   */
  getNotMpRoutes() {
    const { subPackages } = this.pagesJson;
    let routes = [],
      subPages,
      root,
      subRoutes;
    if (subPackages == null || subPackages.length == 0) {
      return [];
    }
    subPackages.forEach((item) => {
      subPages = item.pages;
      root = item.root;
      subRoutes = this.getPagesRoutes(subPages, root);
      routes = routes.concat(subRoutes);
    });
    return routes;
  }
  /**
   * 单条page对象解析
   * @param {Object} pageCallback
   * @param {Object} subPageCallback
   */
  parsePages(pageCallback, subPageCallback) {
    this.PARSEPAGES(this.pagesJson, pageCallback, subPageCallback);
  }

  //历史版本的parsePages
  PARSEPAGES(pagesJson, pageCallback, subPageCallback) {
    if (!pagesJson) {
      pagesJson = this.pagesJson();
    }

    // pages
    pagesJson.pages.forEach((page) => {
      pageCallback && pageCallback(page);
    });
    // subPackages
    if (Array.isArray(pagesJson.subPackages) && pagesJson.subPackages.length) {
      pagesJson.subPackages.forEach((subPackage) => {
        const { root, pages } = subPackage;
        pages.forEach((page) => {
          root && subPageCallback && subPageCallback(root, page, subPackage);
        });
      });
    }
  }
}

export default TransformPages;