import { watch } from 'node:fs';
import { access } from 'node:fs/promises';
import path from 'node:path';
import { spawn } from 'node:child_process';

const repositoryRoot = path.resolve(process.cwd());
const layoutsRoot = path.resolve(process.env.CARD_LAYOUTS_ROOT ?? path.join(repositoryRoot, '../../../tools/card-layouts'));
const renderScript = path.join(repositoryRoot, 'scripts/render_card_layouts.sh');
const watched = [
  [path.join(repositoryRoot, 'json'), name => name === 'card_source.json'],
  [path.join(repositoryRoot, 'doc/assets'), () => true],
  [path.join(layoutsRoot, 'react/src'), name => /\.(tsx?|css)$/.test(name)],
  [path.join(layoutsRoot, 'react'), name => /^(build\.mjs|tsconfig\.json)$/.test(name)],
  [path.join(layoutsRoot, 'tools'), name => name === 'render_card.py'],
  [path.join(layoutsRoot, 'schemas'), name => name === 'card-source.schema.json']
];

let build = null;
let queued = false;
let debounce = null;

function render() {
  if (build) {
    queued = true;
    return;
  }
  process.stdout.write('[card-dev] generowanie karty…\n');
  build = spawn(renderScript, {
    cwd: repositoryRoot,
    env: { ...process.env, CARD_LAYOUTS_ROOT: layoutsRoot },
    stdio: 'inherit'
  });
  build.once('exit', code => {
    build = null;
    process.stdout.write(code === 0
      ? '[card-dev] karta gotowa; przeglądarka odświeży się automatycznie.\n'
      : `[card-dev] generator zakończył się kodem ${code}.\n`);
    if (queued) {
      queued = false;
      render();
    }
  });
}

function scheduleRender() {
  clearTimeout(debounce);
  debounce = setTimeout(render, 180);
}

await access(renderScript);
for (const [directory, accepts] of watched) {
  try {
    await access(directory);
    watch(directory, (_event, filename) => {
      if (filename && accepts(String(filename))) scheduleRender();
    });
    process.stdout.write(`[card-dev] obserwuję ${directory}\n`);
  } catch {
    process.stderr.write(`[card-dev] pomijam brakujący katalog ${directory}\n`);
  }
}

const server = spawn(process.execPath, ['--watch', 'scripts/card_server.mjs'], {
  cwd: repositoryRoot,
  stdio: 'inherit'
});
const stop = signal => {
  if (build) build.kill(signal);
  server.kill(signal);
  process.exit(0);
};
process.on('SIGINT', () => stop('SIGINT'));
process.on('SIGTERM', () => stop('SIGTERM'));

render();