"""
CI/CD Deployment Automation System

This module provides automated deployment scripts and configuration
for continuous integration and deployment pipelines.
"""

import os
import subprocess
import logging
import yaml
from pathlib import Path
from typing import Dict, List, Optional
from datetime import datetime

logger = logging.getLogger(__name__)


class DeploymentManager:
    """
    Manages automated deployment processes for the stream processing application.
    """
    
    def __init__(self, environment: str = 'production'):
        self.environment = environment
        self.project_root = Path(__file__).resolve().parent.parent
        self.deploy_config = self._load_deploy_config()
    
    def _load_deploy_config(self) -> Dict:
        """Load deployment configuration from YAML file."""
        config_path = self.project_root / 'deploy' / f'{self.environment}.yml'
        
        if config_path.exists():
            with open(config_path, 'r') as f:
                return yaml.safe_load(f)
        
        # Default configuration
        return {
            'docker': {
                'registry': 'your-registry.com',
                'image_name': 'stream-processor',
                'tag_prefix': self.environment
            },
            'deployment': {
                'replicas': 3 if self.environment == 'production' else 1,
                'resources': {
                    'cpu': '1000m',
                    'memory': '2Gi'
                }
            }
        }
    
    def run_tests(self) -> bool:
        """
        Run the complete test suite before deployment.
        
        Returns:
            bool: True if all tests pass, False otherwise
        """
        logger.info("Running test suite...")
        
        try:
            # Run pytest with coverage
            result = subprocess.run([
                'python', '-m', 'pytest',
                '--cov=apps',
                '--cov-report=html',
                '--cov-report=term',
                '--tb=short',
                '-v'
            ], cwd=self.project_root, capture_output=True, text=True)
            
            if result.returncode == 0:
                logger.info("All tests passed successfully")
                return True
            else:
                logger.error(f"Tests failed: {result.stdout}\n{result.stderr}")
                return False
                
        except Exception as e:
            logger.error(f"Failed to run tests: {str(e)}")
            return False
    
    def build_docker_image(self) -> bool:
        """
        Build Docker image for deployment.
        
        Returns:
            bool: True if build successful, False otherwise
        """
        logger.info("Building Docker image...")
        
        try:
            timestamp = datetime.now().strftime('%Y%m%d-%H%M%S')
            tag = f"{self.deploy_config['docker']['tag_prefix']}-{timestamp}"
            image_name = f"{self.deploy_config['docker']['registry']}/{self.deploy_config['docker']['image_name']}:{tag}"
            
            # Build web application image
            web_build_cmd = [
                'docker', 'build',
                '-f', 'docker/web.Dockerfile',
                '-t', image_name,
                '.'
            ]
            
            result = subprocess.run(
                web_build_cmd,
                cwd=self.project_root,
                capture_output=True,
                text=True
            )
            
            if result.returncode == 0:
                logger.info(f"Docker image built successfully: {image_name}")
                
                # Also build worker image
                worker_image_name = f"{self.deploy_config['docker']['registry']}/{self.deploy_config['docker']['image_name']}-worker:{tag}"
                worker_build_cmd = [
                    'docker', 'build',
                    '-f', 'docker/worker.Dockerfile',
                    '-t', worker_image_name,
                    '.'
                ]
                
                worker_result = subprocess.run(
                    worker_build_cmd,
                    cwd=self.project_root,
                    capture_output=True,
                    text=True
                )
                
                if worker_result.returncode == 0:
                    logger.info(f"Worker image built successfully: {worker_image_name}")
                    return True
                else:
                    logger.error(f"Worker image build failed: {worker_result.stderr}")
                    return False
            else:
                logger.error(f"Docker build failed: {result.stderr}")
                return False
                
        except Exception as e:
            logger.error(f"Failed to build Docker image: {str(e)}")
            return False
    
    def push_docker_image(self) -> bool:
        """
        Push Docker image to registry.
        
        Returns:
            bool: True if push successful, False otherwise
        """
        logger.info("Pushing Docker image to registry...")
        
        try:
            # This would push the built images to the registry
            # Implementation depends on your registry (Docker Hub, ECR, GCR, etc.)
            logger.info("Docker image push would be implemented here")
            return True
            
        except Exception as e:
            logger.error(f"Failed to push Docker image: {str(e)}")
            return False
    
    def deploy_to_environment(self) -> bool:
        """
        Deploy application to the target environment.
        
        Returns:
            bool: True if deployment successful, False otherwise
        """
        logger.info(f"Deploying to {self.environment} environment...")
        
        try:
            # This would deploy using your orchestration platform
            # (Kubernetes, Docker Swarm, etc.)
            logger.info("Deployment would be implemented here")
            return True
            
        except Exception as e:
            logger.error(f"Deployment failed: {str(e)}")
            return False
    
    def run_health_checks(self) -> bool:
        """
        Run post-deployment health checks.
        
        Returns:
            bool: True if all health checks pass, False otherwise
        """
        logger.info("Running post-deployment health checks...")
        
        try:
            # Check application health endpoint
            # This would make HTTP requests to verify the deployment
            logger.info("Health checks would be implemented here")
            return True
            
        except Exception as e:
            logger.error(f"Health checks failed: {str(e)}")
            return False
    
    def rollback_deployment(self) -> bool:
        """
        Rollback to previous deployment if current deployment fails.
        
        Returns:
            bool: True if rollback successful, False otherwise
        """
        logger.info("Rolling back deployment...")
        
        try:
            # Implement rollback logic
            logger.info("Rollback would be implemented here")
            return True
            
        except Exception as e:
            logger.error(f"Rollback failed: {str(e)}")
            return False
    
    def full_deployment_pipeline(self) -> Dict[str, bool]:
        """
        Execute the complete deployment pipeline.
        
        Returns:
            dict: Results of each deployment step
        """
        results = {
            'tests_passed': False,
            'image_built': False,
            'image_pushed': False,
            'deployed': False,
            'health_checks_passed': False,
            'overall_success': False
        }
        
        try:
            # Step 1: Run tests
            results['tests_passed'] = self.run_tests()
            if not results['tests_passed']:
                logger.error("Deployment aborted: tests failed")
                return results
            
            # Step 2: Build Docker image
            results['image_built'] = self.build_docker_image()
            if not results['image_built']:
                logger.error("Deployment aborted: image build failed")
                return results
            
            # Step 3: Push image to registry
            results['image_pushed'] = self.push_docker_image()
            if not results['image_pushed']:
                logger.error("Deployment aborted: image push failed")
                return results
            
            # Step 4: Deploy to environment
            results['deployed'] = self.deploy_to_environment()
            if not results['deployed']:
                logger.error("Deployment failed")
                return results
            
            # Step 5: Run health checks
            results['health_checks_passed'] = self.run_health_checks()
            if not results['health_checks_passed']:
                logger.warning("Deployment completed but health checks failed")
                # Consider rollback here
                return results
            
            results['overall_success'] = True
            logger.info("Deployment pipeline completed successfully")
            return results
            
        except Exception as e:
            logger.error(f"Deployment pipeline failed: {str(e)}")
            results['error'] = str(e)
            return results


def deploy_application(environment: str = 'production') -> Dict[str, bool]:
    """
    Deploy the application to the specified environment.
    
    Args:
        environment: Target deployment environment
        
    Returns:
        dict: Deployment results
    """
    deployment_manager = DeploymentManager(environment)
    return deployment_manager.full_deployment_pipeline()


def create_deployment_config():
    """
    Create deployment configuration files for different environments.
    """
    configs = {
        'development': {
            'docker': {
                'registry': 'localhost:5000',
                'image_name': 'stream-processor',
                'tag_prefix': 'dev'
            },
            'deployment': {
                'replicas': 1,
                'resources': {
                    'cpu': '500m',
                    'memory': '1Gi'
                }
            }
        },
        'staging': {
            'docker': {
                'registry': 'your-registry.com',
                'image_name': 'stream-processor',
                'tag_prefix': 'staging'
            },
            'deployment': {
                'replicas': 2,
                'resources': {
                    'cpu': '750m',
                    'memory': '1.5Gi'
                }
            }
        },
        'production': {
            'docker': {
                'registry': 'your-registry.com',
                'image_name': 'stream-processor',
                'tag_prefix': 'prod'
            },
            'deployment': {
                'replicas': 3,
                'resources': {
                    'cpu': '1000m',
                    'memory': '2Gi'
                }
            }
        }
    }
    
    # Create deploy directory
    deploy_dir = Path(__file__).resolve().parent
    deploy_dir.mkdir(exist_ok=True)
    
    # Write configuration files
    for env, config in configs.items():
        config_path = deploy_dir / f'{env}.yml'
        with open(config_path, 'w') as f:
            yaml.dump(config, f, default_flow_style=False)
        
        logger.info(f"Created deployment config: {config_path}")