#!/usr/bin/env python3
"""
OpenHands Build Agent Script

Executes build and test tasks using OpenHands SDK.
Designed for GitHub Actions integration.

Usage:
  python agent_build.py

Environment Variables (all required):
  LLM_API_KEY: API key for the LLM
  TASK: Build task to execute
  REPO_NAME: Name of the repository
  COMMIT_SHA: Commit SHA being built

Environment Variables (optional):
  LLM_MODEL: Language model to use (default: anthropic/claude-sonnet-4-5-20250929)
  LLM_BASE_URL: Optional base URL for LLM API
  RETRY_COUNT: Attempt number (for retry logic)
  PREVIOUS_ERRORS: Error messages from previous attempts

Example:
  export LLM_API_KEY="sk-..."
  export TASK="Build and test the project"
  export REPO_NAME="my-project"
  export COMMIT_SHA="abc123def456"
  python agent_build.py
"""

import os
import sys
import logging
import json
from pathlib import Path
from datetime import datetime

from openhands.sdk import LLM, Conversation, get_logger
from openhands.tools.preset.default import get_default_agent


def setup_logging():
    """Configure logging for the build process."""
    # Create logs directory
    logs_dir = Path("build_logs")
    logs_dir.mkdir(exist_ok=True)

    # Setup logger
    logger = get_logger(__name__)

    # Create file handler
    log_file = logs_dir / f"build_{datetime.now().strftime('%Y%m%d_%H%M%S')}.log"
    file_handler = logging.FileHandler(log_file)
    file_handler.setLevel(logging.INFO)

    # Create console handler
    console_handler = logging.StreamHandler()
    console_handler.setLevel(logging.INFO)

    # Format
    formatter = logging.Formatter(
        '%(asctime)s - %(name)s - %(levelname)s - %(message)s'
    )
    file_handler.setFormatter(formatter)
    console_handler.setFormatter(formatter)

    # Get root logger
    root_logger = logging.getLogger()
    root_logger.setLevel(logging.INFO)
    root_logger.addHandler(file_handler)
    root_logger.addHandler(console_handler)

    return logger, log_file


def load_context():
    """Load build context from environment variables."""
    required_vars = ['LLM_API_KEY', 'TASK', 'REPO_NAME', 'COMMIT_SHA']
    missing = [var for var in required_vars if not os.getenv(var)]

    if missing:
        raise ValueError(f"Missing required environment variables: {missing}")

    return {
        'api_key': os.getenv('LLM_API_KEY'),
        'task': os.getenv('TASK'),
        'repo_name': os.getenv('REPO_NAME'),
        'commit_sha': os.getenv('COMMIT_SHA'),
        'retry_count': os.getenv('RETRY_COUNT', '0'),
        'previous_errors': os.getenv('PREVIOUS_ERRORS', ''),
        'model': os.getenv('LLM_MODEL', 'anthropic/claude-sonnet-4-5-20250929'),
        'base_url': os.getenv('LLM_BASE_URL', ''),
    }


def create_llm(config):
    """Create and configure LLM instance."""
    llm_config = {
        'model': config['model'],
        'api_key': config['api_key'],
        'usage_id': f"build-{config['repo_name']}-{config['commit_sha'][:8]}",
        'drop_params': True,
    }

    if config['base_url']:
        llm_config['base_url'] = config['base_url']

    logger.info(f"Initializing LLM: {config['model']}")
    return LLM(**llm_config)


def build_enhanced_task(config):
    """Build enhanced task prompt with context."""
    task_parts = []

    # Header
    task_parts.append("=" * 80)
    task_parts.append(f"BUILD TASK: {config['repo_name']}")
    task_parts.append(f"Commit: {config['commit_sha']}")
    if int(config['retry_count']) > 0:
        task_parts.append(f"Retry Attempt: {config['retry_count']}")
    task_parts.append("=" * 80)
    task_parts.append("")

    # Previous errors (for retry)
    if config['previous_errors']:
        task_parts.append("PREVIOUS BUILD ERRORS:")
        task_parts.append("-" * 80)
        task_parts.append(config['previous_errors'])
        task_parts.append("-" * 80)
        task_parts.append("")
        task_parts.append("Please analyze these errors and fix them in this retry attempt.")
        task_parts.append("")

    # Main task
    task_parts.append("TASK:")
    task_parts.append(config['task'])
    task_parts.append("")

    # Instructions
    task_parts.append("INSTRUCTIONS:")
    task_parts.append("1. Analyze the project structure and identify build system")
    task_parts.append("2. Install dependencies (npm install, pip install, etc.)")
    task_parts.append("3. Run build commands (npm run build, ./build.sh, etc.)")
    task_parts.append("4. Execute tests (npm test, pytest, etc.)")
    task_parts.append("5. Report detailed results:")
    task_parts.append("   - Dependencies installed: YES/NO")
    task_parts.append("   - Build completed: YES/NO")
    task_parts.append("   - Tests passed: YES/NO")
    task_parts.append("   - All errors must be documented")
    task_parts.append("")
    task_parts.append("6. If errors occur:")
    task_parts.append("   - Analyze the error messages")
    task_parts.append("   - Attempt to fix them")
    task_parts.append("   - Retry build process")
    task_parts.append("   - Document what was fixed")
    task_parts.append("")
    task_parts.append("SUCCESS CRITERIA:")
    task_parts.append("- All dependencies installed successfully")
    task_parts.append("- Build completes without errors")
    task_parts.append("- All tests pass")
    task_parts.append("")
    task_parts.append("=" * 80)

    return "\n".join(task_parts)


def save_build_metadata(config, status, duration):
    """Save build metadata to JSON file."""
    metadata = {
        'repo_name': config['repo_name'],
        'commit_sha': config['commit_sha'],
        'retry_count': int(config['retry_count']),
        'status': status,
        'duration_seconds': duration,
        'timestamp': datetime.now().isoformat(),
        'model': config['model'],
    }

    metadata_file = Path("build_metadata.json")
    with open(metadata_file, 'w') as f:
        json.dump(metadata, f, indent=2)

    logger.info(f"Build metadata saved to {metadata_file}")


def main():
    """Execute build task with OpenHands SDK."""
    start_time = datetime.now()
    status = 'unknown'

    try:
        # Setup
        logger, log_file = setup_logging()
        logger.info("=" * 80)
        logger.info("Starting OpenHands Build")
        logger.info("=" * 80)

        # Load context
        config = load_context()
        logger.info(f"Loaded configuration: {config['repo_name']}@{config['commit_sha'][:8]}")

        # Create LLM
        llm = create_llm(config)

        # Create agent with default tools
        logger.info("Initializing OpenHands agent with default tools")
        agent = get_default_agent(llm=llm, cli_mode=True)

        # Create conversation with workspace
        cwd = Path.cwd()
        logger.info(f"Workspace: {cwd}")
        conversation = Conversation(agent=agent, workspace=cwd)

        # Build enhanced task
        task = build_enhanced_task(config)
        logger.info(f"Task prepared ({len(task)} characters)")
        logger.debug(f"Task:\n{task}")

        # Execute task
        logger.info("Sending task to OpenHands agent...")
        conversation.send_message(task)

        logger.info("Running agent conversation...")
        result = conversation.run()

        # Calculate duration
        end_time = datetime.now()
        duration = (end_time - start_time).total_seconds()

        # Save metadata
        status = 'success'
        save_build_metadata(config, status, duration)

        logger.info("=" * 80)
        logger.info(f"Build completed successfully in {duration:.2f} seconds")
        logger.info(f"Logs saved to: {log_file}")
        logger.info("=" * 80)

        return 0

    except Exception as e:
        # Calculate duration
        end_time = datetime.now()
        duration = (end_time - start_time).total_seconds()

        # Log error
        logger.error("=" * 80)
        logger.error(f"Build failed after {duration:.2f} seconds")
        logger.error(f"Error: {str(e)}")
        logger.error("=" * 80)

        # Try to save metadata even on failure
        try:
            config = load_context()
            status = 'failure'
            save_build_metadata(config, status, duration)
        except Exception:
            pass

        return 1


if __name__ == "__main__":
    sys.exit(main())