#!/usr/bin/env python3
import sqlite3
import subprocess
import sys
from datetime import datetime

# --- Configuration ---
DB_PATH = '/www/vmail/postfixadmin.db'
POSTFIX_RELOAD_COMMAND = ['systemctl', 'restart', 'postfix']
# ---------------------

def create_alias(source_email, destination_email):
    """Inserts the alias into the SQLite database."""
    try:
        # We only validate the source here, as the destination is now hardcoded in __main__
        if '@' not in source_email:
            raise ValueError("Source must be a valid email address.")

        # Extract the domain name from the source email
        domain = source_email.split('@')[1]
        
        # Connect to the SQLite database
        # Note: If the database is busy (e.g., mail server is accessing it), this might fail.
        conn = sqlite3.connect(DB_PATH)
        cursor = conn.cursor()
        
        # Get the current datetime for created/modified fields
        now = datetime.now().strftime('%Y-%m-%d %H:%M:%S')

        # Check if the alias already exists
        cursor.execute("SELECT address FROM alias WHERE address=?", (source_email,))
        if cursor.fetchone():
            print(f"[INFO] Alias {source_email} already exists. Updating its destination...")
            sql = """
            UPDATE alias 
            SET goto = ?, modified = ?, active = 1
            WHERE address = ?
            """
            cursor.execute(sql, (destination_email, now, source_email))
        else:
            print(f"[INFO] Creating new alias: {source_email} -> {destination_email}")
            # SQL statement to insert the new alias
            # NOTE: We use the schema you provided earlier (no 'id' or 'domain_id')
            sql = """
            INSERT INTO alias (address, goto, domain, created, modified, active) 
            VALUES (?, ?, ?, ?, ?, 1)
            """
            cursor.execute(sql, (source_email, destination_email, domain, now, now))
        
        conn.commit()
        conn.close()
        print("[SUCCESS] Database update successful.")
        return True

    except ValueError as e:
        print(f"[ERROR] Input Error: {e}")
        return False
    except sqlite3.Error as e:
        print(f"[ERROR] Database Error: An error occurred connecting to or querying the DB at {DB_PATH}.")
        print(f"Error details: {e}")
        return False
    except Exception as e:
        print(f"[ERROR] An unexpected error occurred: {e}")
        return False

def reload_postfix():
    """Executes the Postfix restart/reload command via subprocess."""
    print("[INFO] Attempting to restart Postfix service using systemctl...")
    try:
        # Running as root, so no sudo needed, but check=True ensures error detection
        result = subprocess.run(POSTFIX_RELOAD_COMMAND, check=True, capture_output=True, text=True)
        
        if result.returncode == 0:
            print("[SUCCESS] Postfix restart successful.")
        else:
            print(f"[ERROR] Postfix restart failed with code {result.returncode}.")
            print("Stderr:\n", result.stderr)

    except subprocess.CalledProcessError as e:
        print(f"[ERROR] Postfix restart failed. Command returned non-zero exit status.")
        print(f"Stderr: {e.stderr}")
    except FileNotFoundError:
        print(f"[ERROR] Error: Command '{POSTFIX_RELOAD_COMMAND[0]}' not found. Is Postfix installed?")
    except Exception as e:
        print(f"[ERROR] An unexpected error occurred during Postfix restart: {e}")

if __name__ == "__main__":
    # Hardcode the desired destination email
    FIXED_DESTINATION = 'admin@fullpriceexit.com'
    
    # We now expect only 2 arguments: the script name and the source email
    if len(sys.argv) != 2:
        print("Usage: python3 create_alias.py <source_email>")
        print(f"Note: All created aliases will automatically redirect to {FIXED_DESTINATION}.")
        print("Example: python3 create_alias.py webmaster@fullpriceexit.com")
        sys.exit(1)

    source = sys.argv[1]
    destination = FIXED_DESTINATION # Use the hardcoded destination

    # 1. Create the alias in the database
    if create_alias(source, destination):
        # 2. Restart Postfix to apply changes
        reload_postfix()
        print("\n[COMPLETE] Automation complete.")
    else:
        print("\nProcess aborted due to errors.")