import os
import sys
import paramiko
from dotenv import load_dotenv

sys.stdout.reconfigure(encoding='utf-8')
sys.stderr.reconfigure(encoding='utf-8')

def main():
    repo_root = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
    env_path = os.path.join(repo_root, ".env")
    load_dotenv(dotenv_path=env_path)

    host = os.environ.get('SERVER_HOST')
    user = os.environ.get('SERVER_USER')
    password = os.environ.get('SERVER_PASS')

    if not all([host, user]):
        print("Error: Server credentials not found in .env file.")
        return

    if password == "your_db_password_here" or password == "your_password_here" or not password:
        password = None

    print(f"Connecting to {user}@{host} via SSH...")
    ssh = paramiko.SSHClient()
    ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
    
    try:
        ssh.connect(host, username=user, password=password, timeout=15)
        print("Connected successfully!")
        
        # 1. Bring down and purge old deployment (Uninstall)
        print("\n--- [1/3] Purging existing stack (Docker Compose Down -v) ---")
        stdin, stdout, stderr = ssh.exec_command("cd food_project && docker-compose down -v")
        print("Output:", stdout.read().decode('utf-8'))
        print("Errors/Warnings:", stderr.read().decode('utf-8'))
        
        # 2. Fetch and pull latest code
        print("\n--- [2/3] Pulling latest version from Git ---")
        stdin, stdout, stderr = ssh.exec_command("cd food_project && git fetch origin main && git reset --hard origin/main && git clean -fd")
        print("Output:", stdout.read().decode('utf-8'))
        print("Errors/Warnings:", stderr.read().decode('utf-8'))
        
        # 3. Start up the new stack
        local_model = os.environ.get('LLM_MODEL', 'llama3.2:3b')
        print(f"\n--- [3/3] Launching new stack with model {local_model} ---")
        command = f"cd food_project && sed -i 's/^LLM_MODEL=.*/LLM_MODEL={local_model}/' .env && docker-compose up -d --build"
        stdin, stdout, stderr = ssh.exec_command(command)
        print("Output:", stdout.read().decode('utf-8'))
        print("Errors/Warnings:", stderr.read().decode('utf-8'))
        
        print("\nAll remote operations completed.")
        
    except Exception as e:
        print(f"Error executing remote commands: {e}")
    finally:
        ssh.close()
        print("SSH connection closed.")

if __name__ == "__main__":
    main()