#!/usr/bin/env node

const fs = require('node:fs');
const path = require('node:path');

const root = __dirname;
const compiled_root = path.join(root, '.swp/compiled');
const link_pattern = /\[[^\]]*\]\(([^)\s]+)\)/g;

function scan(directory) {
  for (const entry of fs.readdirSync(directory, { withFileTypes: true })) {
    if (entry.name.startsWith('.')) {
      continue;
    }

    const file = path.join(directory, entry.name);

    if (entry.isDirectory()) {
      scan(file);
    } else if (entry.isFile() && entry.name.endsWith('.md')) {
      for (const match of fs.readFileSync(file, 'utf8').matchAll(link_pattern)) {
        const url = match[1].split(/[?#]/, 1)[0];

        if (!url.endsWith('.html') || /^[a-z][a-z0-9+.-]*:/i.test(url)) {
          continue;
        }

        const target = url.replace(/^\//, '');
        const base = url.startsWith('/')
          ? compiled_root
          : path.join(compiled_root, path.relative(root, path.dirname(file)));

        if (!fs.existsSync(path.resolve(base, target)) &&
            !fs.existsSync(path.resolve(compiled_root, target))) {
          console.log(match[0]);
        }
      }
    }
  }
}

scan(process.cwd());