import {
  assert,
  codedError,
  hashValue,
  sleep,
  throwIfShutdownRequested,
} from '../assertions/core.mjs';
import { fs, path, spawn, withLoopbackNoProxy } from '../dependencies.mjs';
import {
  activeCommandChildren,
  appRoot,
  commandOutputLimit,
  manifestPath,
  state,
} from '../runtime-state.mjs';
import {
  isSupervisorSwarmTransientRetrySuite,
  recordSupervisorSwarmChatSessionFailureDiagnostic,
} from '../suites/supervisor-swarm.mjs';
import { isIsolatedRunnerSuite } from './reporting.mjs';

export async function prepareCliBinary() {
  const cargo = process.platform === 'win32' ? 'cargo.exe' : 'cargo';
  await runProcess(
    cargo,
    ['build', '--quiet', '--manifest-path', manifestPath],
    {
      cwd: appRoot,
      timeoutMs: 15 * 60 * 1000,
    },
  );
  const metadata = await runProcess(
    cargo,
    [
      'metadata',
      '--format-version',
      '1',
      '--no-deps',
      '--manifest-path',
      manifestPath,
    ],
    { cwd: appRoot, timeoutMs: 120_000 },
  );
  const parsed = JSON.parse(metadata.stdout);
  const executable = path.join(
    parsed.target_directory,
    'debug',
    `genarrative-ai-game-creator-shell${process.platform === 'win32' ? '.exe' : ''}`,
  );
  const binary = await fs.stat(executable).catch(() => null);
  assert(binary?.isFile(), 'cli-binary-missing');
  return executable;
}

export async function runCli(args, options = {}) {
  assert(Boolean(state.cliBinary), 'cli-binary-not-ready');
  assert(Boolean(state.runtimeConfigDir), 'runtime-config-dir-not-ready');
  if (
    isIsolatedRunnerSuite() &&
    state.options?.configDir &&
    path.resolve(state.runtimeConfigDir) ===
      path.resolve(state.options.configDir)
  ) {
    state.isolatedRunner.sourceConfigCliCallCount += 1;
  }
  return runProcess(
    state.cliBinary,
    [...args, '--config-dir', state.runtimeConfigDir],
    {
      cwd: appRoot,
      timeoutMs: options.timeoutMs ?? 60_000,
      stdin: options.stdin,
      allowNonZero: options.allowNonZero ?? false,
      env: buildCliChildEnvironment(),
    },
  );
}

export function buildCliChildEnvironment() {
  const environment = {
    ...process.env,
    NO_COLOR: '1',
    RUST_BACKTRACE: '0',
  };
  return isSupervisorSwarmTransientRetrySuite()
    ? withLoopbackNoProxy(environment)
    : environment;
}

export function safeProcessFailureDiagnostic({
  code = null,
  signal = null,
  error = null,
  stdout = '',
  stderr = '',
} = {}) {
  const stdoutText = Buffer.isBuffer(stdout)
    ? stdout.toString('utf8')
    : String(stdout);
  const stderrText = Buffer.isBuffer(stderr)
    ? stderr.toString('utf8')
    : String(stderr);
  const combined = `${error?.message ?? ''}\n${stdoutText}\n${stderrText}`;
  const processErrorCode = /^[A-Z0-9_]+$/u.test(error?.code ?? '')
    ? error.code
    : 'none';
  const closeSignal = /^[A-Z0-9]+$/u.test(signal ?? '') ? signal : 'none';
  let failureKind = 'closed';
  if (
    processErrorCode === 'ENOSPC' ||
    /(?:\bENOSPC\b|No space left on device|os error 28)/iu.test(combined)
  ) {
    failureKind = 'enospc';
  } else if (processErrorCode !== 'none') {
    failureKind = 'process-error';
  } else if (closeSignal !== 'none') {
    failureKind = 'signal';
  } else if (Number.isInteger(code) && code !== 0) {
    failureKind = 'nonzero-exit';
  }
  return {
    failureKind,
    exitCode: Number.isInteger(code) ? String(code) : 'none',
    signal: closeSignal,
    processErrorCode,
    stderrChars: [...stderrText].length,
    stderrSha256: hashValue(stderrText) ?? 'none',
  };
}

export function codedProcessError(code, details) {
  const error = codedError(code, details?.error);
  error.safeFailureDiagnostic = safeProcessFailureDiagnostic(details);
  return error;
}

export function startInteractiveCli(args) {
  assert(Boolean(state.cliBinary), 'interactive-cli-binary-not-ready');
  assert(Boolean(state.runtimeConfigDir), 'interactive-config-dir-not-ready');
  if (
    isIsolatedRunnerSuite() &&
    state.options?.configDir &&
    path.resolve(state.runtimeConfigDir) ===
      path.resolve(state.options.configDir)
  ) {
    state.isolatedRunner.sourceConfigCliCallCount += 1;
  }
  const child = spawn(
    state.cliBinary,
    [...args, '--config-dir', state.runtimeConfigDir],
    {
      cwd: appRoot,
      env: buildCliChildEnvironment(),
      stdio: ['pipe', 'pipe', 'pipe'],
    },
  );
  activeCommandChildren.add(child);
  const session = {
    child,
    stdout: Buffer.alloc(0),
    stderr: Buffer.alloc(0),
    closed: false,
    closeInfo: null,
    closePromise: null,
  };
  session.closePromise = new Promise((resolve) => {
    child.on('error', (error) => {
      activeCommandChildren.delete(child);
      session.closed = true;
      session.closeInfo = { code: null, signal: null, error };
      resolve(session.closeInfo);
    });
    child.on('close', (code, signal) => {
      activeCommandChildren.delete(child);
      session.closed = true;
      session.closeInfo = { code, signal, error: null };
      resolve(session.closeInfo);
    });
  });
  child.stdout.on('data', (chunk) => {
    state.transcriptScanner?.scan('interactive-stdout', chunk);
    state.formalConfigPathTranscriptScanner?.scan('interactive-stdout', chunk);
    session.stdout = appendBounded(session.stdout, chunk, commandOutputLimit);
  });
  child.stderr.on('data', (chunk) => {
    state.transcriptScanner?.scan('interactive-stderr', chunk);
    state.formalConfigPathTranscriptScanner?.scan('interactive-stderr', chunk);
    session.stderr = appendBounded(session.stderr, chunk, commandOutputLimit);
  });
  return session;
}

export function interactiveCliOutput(session) {
  return `${session.stdout.toString('utf8')}\n${session.stderr.toString('utf8')}`;
}

export function writeInteractiveCliLine(session, line) {
  assert(!session.closed, 'interactive-cli-already-closed');
  assert(session.child.stdin.writable, 'interactive-cli-stdin-not-writable');
  session.child.stdin.write(`${line}\n`);
}

export async function waitForInteractiveCliOutput(
  session,
  predicate,
  code,
  timeoutMs,
) {
  const deadline = Date.now() + timeoutMs;
  while (Date.now() < deadline) {
    const output = interactiveCliOutput(session);
    if (predicate(output)) return output;
    if (session.closed) {
      if (session === state.supervisorSwarmCliSession) {
        recordSupervisorSwarmChatSessionFailureDiagnostic(session);
      }
      throw codedError(`${code}-cli-closed`);
    }
    await sleep(50);
  }
  throw codedError(code);
}

export async function waitForInteractiveCliExit(session, timeoutMs) {
  const result = await Promise.race([
    session.closePromise,
    sleep(timeoutMs).then(() => null),
  ]);
  if (!result) throw codedError('interactive-cli-exit-timeout');
  if (result.error) throw codedError('interactive-cli-process-error');
  assert(
    result.code === 0 && result.signal === null,
    'interactive-cli-exit-invalid',
  );
  return result;
}

export async function closeInteractiveCli(session) {
  if (!session || session.closed) return;
  if (session.child.stdin.writable) {
    session.child.stdin.write('/quit\n');
  }
  let result = await Promise.race([
    session.closePromise,
    sleep(3_000).then(() => null),
  ]);
  if (!result && !session.closed) {
    session.child.kill('SIGTERM');
    result = await Promise.race([
      session.closePromise,
      sleep(2_000).then(() => null),
    ]);
  }
  if (!result && !session.closed) {
    session.child.kill('SIGKILL');
    result = await session.closePromise;
  }
  assert(Boolean(result), 'interactive-cli-cleanup-timeout');
}

export async function runProcess(
  program,
  args,
  { cwd, timeoutMs, stdin, allowNonZero = false, env = null },
) {
  throwIfShutdownRequested();
  return new Promise((resolve, reject) => {
    const child = spawn(program, args, {
      cwd,
      env: env ?? { ...process.env, NO_COLOR: '1', RUST_BACKTRACE: '0' },
      stdio: [stdin === undefined ? 'ignore' : 'pipe', 'pipe', 'pipe'],
    });
    activeCommandChildren.add(child);
    let stdout = Buffer.alloc(0);
    let stderr = Buffer.alloc(0);
    let timedOut = false;
    const timer = setTimeout(() => {
      timedOut = true;
      child.kill('SIGKILL');
    }, timeoutMs);
    child.stdout.on('data', (chunk) => {
      state.transcriptScanner?.scan('stdout', chunk);
      state.projectPathTranscriptScanner?.scan('stdout', chunk);
      state.formalConfigPathTranscriptScanner?.scan('stdout', chunk);
      stdout = appendBounded(stdout, chunk, commandOutputLimit);
    });
    child.stderr.on('data', (chunk) => {
      state.transcriptScanner?.scan('stderr', chunk);
      state.projectPathTranscriptScanner?.scan('stderr', chunk);
      state.formalConfigPathTranscriptScanner?.scan('stderr', chunk);
      stderr = appendBounded(stderr, chunk, commandOutputLimit);
    });
    child.on('error', (error) => {
      clearTimeout(timer);
      activeCommandChildren.delete(child);
      reject(
        codedProcessError('process-spawn-failed', {
          error,
          stdout,
          stderr,
        }),
      );
    });
    child.on('close', (code, signal) => {
      clearTimeout(timer);
      activeCommandChildren.delete(child);
      const result = {
        stdout: stdout.toString('utf8'),
        stderr: stderr.toString('utf8'),
        code,
        signal,
      };
      if (timedOut) {
        reject(codedProcessError('process-timeout', result));
      } else if (state.shutdownSignal && !state.cleanupInProgress) {
        reject(
          codedProcessError(
            `interrupted-${state.shutdownSignal.toLowerCase()}`,
            result,
          ),
        );
      } else if (code !== 0 && !allowNonZero) {
        reject(codedProcessError('cli-command-failed', result));
      } else {
        resolve(result);
      }
    });
    if (stdin !== undefined) child.stdin.end(stdin);
  });
}

export function appendBounded(current, chunk, limit) {
  const combined = Buffer.concat([current, chunk]);
  return combined.length <= limit
    ? combined
    : combined.subarray(combined.length - limit);
}