import { spawn } from 'node:child_process';
import { mkdirSync, readFileSync } from 'node:fs';
import { Database } from 'bun:sqlite';
import { createServer } from 'node:net';
import { dirname, join } from 'node:path';
import { buildLocalDevConfig, resolveSqlitePath } from './dev-env';

type DrizzleJournal = {
  entries: Array<{ tag: string }>;
};

type ExitResult = {
  code: number | null;
  signal: NodeJS.Signals | null;
};

function trim(value: string | undefined) {
  const candidate = value?.trim();
  return candidate ? candidate : undefined;
}

async function isPortAvailable(port: number, host: string) {
  return await new Promise<boolean>((resolve) => {
    const server = createServer();

    server.once('error', () => resolve(false));
    server.listen(port, host, () => {
      server.close(() => resolve(true));
    });
  });
}

async function pickLocalPort(host: string) {
  const candidatePorts = [3000, 3001, 3002, 3100, 3200, 3300];

  for (const port of candidatePorts) {
    if (await isPortAvailable(port, host)) {
      return String(port);
    }
  }

  throw new Error(`Unable to find an open local dev port from: ${candidatePorts.join(', ')}`);
}

function hasTable(database: Database, tableName: string) {
  const row = database
    .query('SELECT name FROM sqlite_master WHERE type = ? AND name = ? LIMIT 1')
    .get('table', tableName) as { name: string } | null;

  return row !== null;
}

function readMigrationFiles() {
  const journal = JSON.parse(
    readFileSync(join(process.cwd(), 'drizzle', 'meta', '_journal.json'), 'utf8')
  ) as DrizzleJournal;

  return journal.entries.map((entry) => join(process.cwd(), 'drizzle', `${entry.tag}.sql`));
}

function bootstrapFreshDatabase(databaseUrl: string) {
  const databasePath = resolveSqlitePath(databaseUrl);
  if (!databasePath || databasePath === ':memory:') {
    return false;
  }

  mkdirSync(dirname(databasePath), { recursive: true });

  const database = new Database(databasePath, { create: true });

  try {
    database.exec('PRAGMA foreign_keys = ON;');

    const existingCoreTables = [
      'user',
      'filing',
      'watchlist_item',
      'filing_statement_snapshot',
      'filing_taxonomy_snapshot',
      'task_run'
    ];

    if (existingCoreTables.some((tableName) => hasTable(database, tableName))) {
      return false;
    }

    for (const migrationFile of readMigrationFiles()) {
      database.exec(readFileSync(migrationFile, 'utf8'));
    }

    return true;
  } finally {
    database.close();
  }
}

function exitFromResult(result: ExitResult) {
  if (result.signal) {
    process.exit(result.signal === 'SIGINT' || result.signal === 'SIGTERM' ? 0 : 1);
    return;
  }

  process.exit(result.code ?? 0);
}

const explicitPort = trim(process.env.PORT) || trim(process.env.APP_PORT);
const bindHost = trim(process.env.HOSTNAME) || trim(process.env.HOST) || '127.0.0.1';
const resolvedPort = explicitPort || await pickLocalPort(bindHost);
const config = buildLocalDevConfig({
  ...process.env,
  HOSTNAME: bindHost,
  PORT: resolvedPort
});
const env = {
  ...config.env
} as NodeJS.ProcessEnv;

delete env.NO_COLOR;

const databasePath = resolveSqlitePath(env.DATABASE_URL ?? '');
if (databasePath && databasePath !== ':memory:') {
  mkdirSync(dirname(databasePath), { recursive: true });
}

mkdirSync(env.WORKFLOW_LOCAL_DATA_DIR ?? '.workflow-data', { recursive: true });

const initializedDatabase = bootstrapFreshDatabase(env.DATABASE_URL ?? '');

console.info(`[dev] local origin ${config.publicOrigin}`);
console.info(`[dev] sqlite ${env.DATABASE_URL}`);
console.info(`[dev] workflow ${env.WORKFLOW_TARGET_WORLD} (${env.WORKFLOW_LOCAL_DATA_DIR})`);
if (!explicitPort && resolvedPort !== '3000') {
  console.info(`[dev] port 3000 is busy, using http://localhost:${resolvedPort} instead`);
}
if (initializedDatabase) {
  console.info('[dev] initialized the local SQLite schema from drizzle SQL files');
}

if (config.overrides.authOriginChanged) {
  console.info('[dev] forcing Better Auth origin/trusted origins to the local origin');
}

if (config.overrides.apiBaseChanged) {
  console.info('[dev] forcing NEXT_PUBLIC_API_URL to same-origin for local dev');
}

if (config.overrides.databaseChanged) {
  console.info('[dev] using a local SQLite database instead of the deployment path');
}

if (config.overrides.workflowChanged) {
  console.info('[dev] forcing Workflow to the local runtime for local dev');
}

if (config.overrides.secretFallbackUsed) {
  console.info('[dev] using the built-in local Better Auth secret because BETTER_AUTH_SECRET is unset or still a placeholder');
}

const child = spawn(
  'bun',
  ['--bun', 'next', 'dev', '--turbopack', '--hostname', config.bindHost, '--port', config.port],
  {
    env,
    stdio: 'inherit'
  }
);

function forwardSignal(signal: NodeJS.Signals) {
  if (!child.killed) {
    child.kill(signal);
  }
}

process.on('SIGINT', () => forwardSignal('SIGINT'));
process.on('SIGTERM', () => forwardSignal('SIGTERM'));

child.on('exit', (code, signal) => {
  exitFromResult({ code, signal });
});