#!/usr/bin/env node

const fs = require("fs-extra");
const { glob } = require("glob");
const path = require("path");
const { loadJsonFileSync } = require("load-json-file");
const yaml = require("yamljs");

(async () => {
  // documentation v14 has moved to ESM so need to import as if async, and wrap
  // in an IIFE as top level async not allowed.
  const documentation = await import("documentation");

  /**
   * When firing `npm run docs`:
   *   - inside a module, only the docs of that module will be generated
   *   - outside or at the root level it will generate docs for all modules
   */
  const currentFolder = process.cwd().split(path.sep).pop() as string;
  const packages = currentFolder.includes("packages/turf-")
    ? [path.join(process.cwd(), "package.json")]
    : glob.sync(
        path.join(__dirname, "..", "packages", "turf-*", "package.json")
      );

  // Template for README Markdown
  const postfix = fs.readFileSync(path.join(__dirname, "postfix.md"), "utf8");

  const paths = yaml.parse(
    fs.readFileSync(path.join(__dirname, "..", "documentation.yml"), "utf8")
  ).paths;

  packages.forEach((packagePath) => {
    const directory = path.parse(packagePath).dir;
    let indexPath = path.join(directory, "index.js");
    const pckg = loadJsonFileSync(packagePath);
    const name = pckg.name;
    const diagrams = glob
      .sync(path.join(directory, "diagrams", "*"))
      .filter(isImage);

    // some of the packages are typescript instead
    if (!fs.existsSync(indexPath)) {
      indexPath = path.join(directory, "index.ts");
    }

    // Build Documentation
    documentation
      .build(indexPath, { shallow: true })
      .then((res) => {
        if (res === undefined) return console.warn(packagePath);
        console.log("Building Docs: " + name);

        // Format Markdown
        documentation.formats
          .md(res, { paths })
          .then((markdown) => {
            markdown = `# ${name}\n\n${markdown}${postfix.replace(
              /{module}/,
              name
            )}`;
            if (diagrams.length)
              markdown += "\n\n### Diagrams\n\n" + diagramToMarkdown(diagrams);
            fs.writeFileSync(path.join(directory, "README.md"), markdown);
          })
          .catch((error) => console.warn(error));
      })
      .catch((error) => console.warn(error));
  });
})();

function isImage(image) {
  return [".gif", ".jpg", ".png"].indexOf(path.parse(image).ext) !== -1;
}

function diagramToMarkdown(diagrams) {
  return diagrams
    .map((image) => {
      const { name, base } = path.parse(image);
      return `![${name}](diagrams/${base})`;
    })
    .join("\n");
}