import { readdir, writeFile, mkdir } from 'node:fs/promises';
import { join, resolve } from 'node:path';
import { loadTheme } from './src/palette.js';
import { buildVariables } from './src/themeBuilder.js';
import { renderThemeCSS } from './src/cssWriter.js';

const DOKI_REPO = resolve(process.env['DOKI_REPO'] ?? './doki-master-theme');
const OUTPUT_DIR = resolve(process.env['OUTPUT_DIR'] ?? './output');

async function findDefinitionFiles(dir: string): Promise<string[]> {
  const entries = await readdir(dir, { recursive: true });
  return entries
    .filter((f) => f.endsWith('.master.definition.json'))
    .map((f) => join(dir, f));
}

async function main(): Promise<void> {
  await mkdir(OUTPUT_DIR, { recursive: true });

  const definitionsDir = join(DOKI_REPO, 'definitions');
  const definitionFiles = await findDefinitionFiles(definitionsDir);

  if (definitionFiles.length === 0) {
    console.error(`No definition files found in ${definitionsDir}`);
    console.error('Make sure the doki-master-theme submodule is initialised:');
    console.error('  git submodule update --init');
    process.exit(1);
  }

  let success = 0;
  let errors = 0;

  for (const defPath of definitionFiles) {
    try {
      const theme = loadTheme(defPath, DOKI_REPO);
      const variables = buildVariables(theme);
      const css = renderThemeCSS(theme, variables);

      const outPath = join(OUTPUT_DIR, `theme-${theme.internalName}.css`);
      await writeFile(outPath, css, 'utf8');

      console.log(`✓ ${theme.internalName}`);
      success++;
    } catch (err) {
      console.error(`✗ ${defPath}: ${err}`);
      errors++;
    }
  }

  console.log(`\nGenerated ${success} theme${success !== 1 ? 's' : ''}. Errors: ${errors}.`);
}

main();