import { outputFile } from "fs-extra";
import * as path from "path";
import { walk } from "walk";

export const relativePath = (...relativePath: string[]): string =>
  path.resolve(...relativePath);

export const radarPath = (...pathInSrc: string[]) =>
  relativePath("radar", ...pathInSrc);

export const stylesPath = (...pathInSrc: string[]) =>
  relativePath("styles", ...pathInSrc);

export const faviconPath = (...pathInSrc: string[]) =>
  relativePath("assets/favicon.ico", ...pathInSrc);

export const jsPath = (...pathInSrc: string[]) =>
  relativePath("js", ...pathInSrc);

export const buildPath = (...pathInDist: string[]) =>
  relativePath("build", ...pathInDist);

export const getAllMarkdownFiles = (folder: string) =>
  getAllFiles(folder, isMarkdownFile);

const getAllFiles = (
  folder: string,
  predicate: (s: string) => boolean
): Promise<string[]> =>
  new Promise((resolve, reject) => {
    const walker = walk(folder, { followLinks: false });
    const files: string[] = [];

    walker.on("file", (root, fileStat, next) => {
      if (predicate(fileStat.name)) {
        files.push(path.resolve(root, fileStat.name));
      }
      next();
    });

    walker.on("errors", (root, nodeStatsArray, next) => {
      nodeStatsArray.forEach(function (n) {
        console.error("[ERROR] " + n.name);
        if (n.error) {
          console.error(n.error.message || n.error.code + ": " + n.error.path);
        }
      });
      next();
    });

    walker.on("end", () => {
      resolve(files.sort());
    });
  });

const isMarkdownFile = (name: string) => name.match(/\.md$/) !== null;

export const save = (data: string | Buffer | DataView, fileName: string) =>
  outputFile(buildPath(fileName), data);