/**
 * Dev script that generates src/environments/environment.local.ts from
 * .env.local (or process.env) before starting `ng serve`.
 *
 * Angular's esbuild-based builder doesn't read .env files like Vite does,
 * so we generate a TypeScript environment file and use Angular's
 * fileReplacements to swap it in during the development build.
 */
import { readFileSync, writeFileSync, existsSync, mkdirSync } from 'fs';
import { spawn } from 'child_process';

/** Parse a .env file into a key-value object. */
function parseEnvFile(filePath) {
  const vars = {};
  if (!existsSync(filePath)) return vars;

  for (const line of readFileSync(filePath, 'utf-8').split('\n')) {
    const trimmed = line.trim();
    if (!trimmed || trimmed.startsWith('#')) continue;
    const eqIdx = trimmed.indexOf('=');
    if (eqIdx === -1) continue;
    vars[trimmed.slice(0, eqIdx)] = trimmed.slice(eqIdx + 1);
  }
  return vars;
}

const envFile = parseEnvFile('.env.local');

// Resolve each variable: prefer process.env (set by `spacetime dev`),
// then .env.local, then fall back to the defaults in environment.ts.
const dbName =
  process.env.SPACETIMEDB_DB_NAME ||
  envFile.VITE_SPACETIMEDB_DB_NAME ||
  'angular-ts';
const host =
  process.env.SPACETIMEDB_HOST ||
  envFile.VITE_SPACETIMEDB_HOST ||
  'https://maincloud.spacetimedb.com';

mkdirSync('src/environments', { recursive: true });
writeFileSync(
  'src/environments/environment.local.ts',
  [
    '// Auto-generated by scripts/dev.mjs — do not edit manually.',
    'export const environment = {',
    `  SPACETIMEDB_HOST: '${host}',`,
    `  SPACETIMEDB_DB_NAME: '${dbName}',`,
    '};',
    '',
  ].join('\n')
);

const child = spawn('npx', ['ng', 'serve'], {
  stdio: 'inherit',
  shell: true,
});

child.on('exit', (code) => process.exit(code ?? 0));