"""Exercise the deployment exit handler with synthetic image references and no Docker."""
import os
from pathlib import Path
import shutil
import subprocess
import unittest

ROOT = Path(__file__).resolve().parents[1]
BASH = 'C:/Program Files/Git/bin/bash.exe' if os.name == 'nt' else shutil.which('bash')


class DeployRollbackTests(unittest.TestCase):
    def exit_deploy(self, status, *, replaced=True, backend=True, frontend=True, compose_status=0):
        source = (ROOT / 'deploy/deploy.sh').read_text(encoding='utf-8')
        start = source.index('finish_deploy() {')
        handler = source[start:source.index('\ntrap finish_deploy EXIT\n', start) + len('\ntrap finish_deploy EXIT\n')]
        script = '\n'.join([
            'set -euo pipefail',
            f'replacement_started={str(replaced).lower()}',
            'previous_backend_ref=' + ('synthetic/backend:previous' if backend else ''),
            'previous_frontend_ref=' + ('synthetic/frontend:previous' if frontend else ''),
            'auth_config_body_file=synthetic-body',
            'auth_config_headers_file=synthetic-headers',
            'rm() { printf "CALL rm %s\\n" "$*"; }',
            'docker() { echo "CALL unexpected docker"; return 99; }',
            'curl() { echo "CALL unexpected curl"; return 99; }',
            'compose() {',
            '  printf "CALL compose %s [%s] [%s]\\n" "$*" "${BACKEND_IMAGE:-}" "${FRONTEND_IMAGE:-}";',
            f'  if [ "$1" = up ]; then return {compose_status}; fi;',
            '  return 0;',
            '}',
            handler,
            f'exit {status}',
        ])
        # Exclude inherited deployment settings from the fixture.
        environment = {key: value for key, value in os.environ.items()
                       if key.upper() in {'PATH', 'SYSTEMROOT', 'WINDIR', 'TEMP', 'TMP'}}
        result = subprocess.run([BASH, '--noprofile', '--norc'], input=script,
                                text=True, encoding='utf-8', capture_output=True,
                                cwd=ROOT, env=environment, timeout=10)
        self.assertEqual(status, result.returncode, result.stdout + result.stderr)
        self.assertEqual('', result.stderr)
        calls = [line for line in result.stdout.splitlines() if line.startswith('CALL ')]
        self.assertEqual(['CALL rm -f synthetic-body', 'CALL rm -f synthetic-headers'], calls[:2])
        return result.stdout, calls[2:]

    def test_failed_replacement_recreates_only_prior_core_images(self):
        stdout, calls = self.exit_deploy(41)
        self.assertEqual([
            'CALL compose up -d --force-recreate --remove-orphans backend frontend '
            '[synthetic/backend:previous] [synthetic/frontend:previous]',
        ], calls)
        self.assertIn('Deployment remains failed', stdout)

    def test_rollback_failure_retains_original_status_and_collects_diagnostics(self):
        stdout, calls = self.exit_deploy(41, compose_status=19)
        self.assertEqual([
            'CALL compose up -d --force-recreate --remove-orphans backend frontend '
            '[synthetic/backend:previous] [synthetic/frontend:previous]',
            'CALL compose ps [] []',
            'CALL compose logs --tail=200 backend frontend [] []',
        ], calls)
        self.assertIn('Manual recovery is required', stdout)

    def test_incomplete_previous_release_does_not_recreate_any_service(self):
        for backend, frontend in [(False, True), (True, False), (False, False)]:
            with self.subTest(backend=backend, frontend=frontend):
                stdout, calls = self.exit_deploy(41, backend=backend, frontend=frontend)
                self.assertEqual([], calls)
                self.assertIn('no complete previous core release', stdout)

    def test_failure_before_replacement_does_not_recreate_any_service(self):
        _, calls = self.exit_deploy(41, replaced=False)
        self.assertEqual([], calls)

    def test_success_does_not_recreate_any_service(self):
        _, calls = self.exit_deploy(0)
        self.assertEqual([], calls)


if __name__ == '__main__':
    unittest.main()