import json
import sys

import click
from pathlib import Path
import logging
import re

from iottb import definitions
from iottb.models.device_metadata import DeviceMetadata
from iottb.models.iottb_config import IottbConfig
from iottb.definitions import CFG_FILE_PATH, TB_ECHO_STYLES

logger = logging.getLogger(__name__)


def prompt_for_device_details():
    device_details = {}
    aliases = []
    while True:
        click.echo("\nEnter the details for the new device:")
        click.echo("1. Device Name")
        click.echo("2. Description")
        click.echo("3. Model")
        click.echo("4. Manufacturer")
        click.echo("5. Current Firmware Version")
        click.echo("6. Device Type")
        click.echo("7. Supported Interfaces")
        click.echo("8. Companion Applications")
        click.echo("9. Add Alias")
        click.echo("10. Finish and Save")

        choice = click.prompt("Choose an option", type=int)

        if choice == 1:
            device_details['device_name'] = click.prompt("Enter the device name")
        elif choice == 2:
            device_details['description'] = click.prompt("Enter the description")
        elif choice == 3:
            device_details['model'] = click.prompt("Enter the model")
        elif choice == 4:
            device_details['manufacturer'] = click.prompt("Enter the manufacturer")
        elif choice == 5:
            device_details['firmware_version'] = click.prompt("Enter the current firmware version")
        elif choice == 6:
            device_details['device_type'] = click.prompt("Enter the device type")
        elif choice == 7:
            device_details['supported_interfaces'] = click.prompt("Enter the supported interfaces")
        elif choice == 8:
            device_details['companion_applications'] = click.prompt("Enter the companion applications")
        elif choice == 9:
            alias = click.prompt("Enter an alias")
            aliases.append(alias)
        elif choice == 10:
            break
        else:
            click.echo("Invalid choice. Please try again.")

    device_details['aliases'] = aliases
    return device_details


def confirm_and_add_device(device_details, db_path):
    click.echo("\nDevice metadata:")
    for key, value in device_details.items():
        click.echo(f"{key.replace('_', ' ').title()}: {value}")

    confirm = click.confirm("Do you want to add this device with above metadata?")
    if confirm:
        device_name = device_details.get('device_name')
        if not device_name:
            click.echo("Device name is required. Exiting...")
            return

        device_metadata = DeviceMetadata(**device_details)
        device_dir = db_path / device_metadata.canonical_name

        if device_dir.exists():
            click.echo(f"Device {device_name} already exists in the database.")
            click.echo("Exiting...")
            return

        try:
            device_dir.mkdir(parents=True, exist_ok=True)
            metadata_path = device_dir / definitions.DEVICE_METADATA_FILE_NAME
            device_metadata.save_metadata_to_file(metadata_path)
            click.echo(f"Successfully added device {device_name} to database.")
        except OSError as e:
            click.echo(f"Error trying to create device directory: {e}")
            click.echo("Exiting...")
    else:
        click.echo("Operation cancelled. Exiting...")


def add_device_guided(cfg, db):
    logger.info('Adding device interactively')
    # logger.debug(f'Parameters: {params}. value: {value}')
    databases = cfg.db_path_dict
    if not databases:
        click.echo('No databases found in config file.')
        return
    click.echo('Available Databases:')
    last = 0
    for i, db_name in enumerate(databases.keys(), start=1):
        click.echo(f'[{i}] {db_name}')
        last = i if last < i else last
    db_choice = click.prompt('Select the database to add the new device to  (1 - {last}, 0 to quit)',
                             type=int, default=1)
    if 1 <= db_choice <= last:
        selected_db = list(databases.keys())[db_choice - 1]
        click.confirm(f'Use {selected_db}?', abort=True)
        db_path = Path(databases[selected_db]) / selected_db
        logger.debug(f'DB Path {str(db_path)}')
        device_details = prompt_for_device_details()
        confirm_and_add_device(device_details, db_path)
    elif db_choice == 0:
        click.echo(f'Quitting...')
    else:
        click.echo(f'{db_choice} is not a valid choice. Please rerun command and select a valid database.')


@click.command('add-device', help='Add a device to a database')
@click.argument('device', type=str, default="")
@click.option('--db', '--database', type=str,
              envvar='IOTTB_DB', show_envvar=True, default="",
              help='Database in which to add this device. If not specified use default from config.')
@click.option('--guided', is_flag=True,
              help='Add device interactively')
def add_device(device, db, guided):
    """Add a new device to a database

        Device name must be supplied unless in an interactive setup. 
        Database is taken from config by default.
        If this device name contains spaces or other special characters normalization is performed to derive a canonical name.
    """
    logger.info('add-device invoked')

    # Step 1: Load Config
    # Dependency: Config file must exist
    config = IottbConfig(Path(CFG_FILE_PATH))
    logger.debug(f'Config loaded: {config}')
    # If guided flag set, continue with guided add and leave
    if guided:
        click.echo('Guided option set. Continuing with guided add.')
        add_device_guided(config, device, db)
        logger.info('Finished guided device add.')
        return

    # Step 2: Load database
    # dependency: Database folder must exist
    if db != "":
        database = db
        path = config.db_path_dict[database]
        logger.debug(f'Resolved (path, db) {path}, {database}')
    else:
        path = config.default_db_location
        database = config.default_database
        logger.debug(f'Default (path, db) {path}, {database}')
    click.secho(f'Using database {database}')
    full_db_path = Path(path) / database
    if not full_db_path.is_dir():
        logger.warning(f'No database at {database}')
        click.echo(f'No database found at {full_db_path}', lvl='w')
        click.echo(
            f'You need to initialize the testbed before before you add devices!')
        click.echo(
            f'To initialize the testbed in the default location run "iottb init-db"')
        click.echo('Exiting...')
        sys.exit()
    # Ensure a device name was passed as argument
    if device == "":
        click.echo("Device name cannot be an empty string. Exiting...", lvl='w')
        return

    # Step 3: Check if device already exists in database
    # dependency: DeviceMetadata object
    device_metadata = DeviceMetadata(device_name=device)
    device_dir = full_db_path / device_metadata.canonical_name

    # Check if device is already registered
    if device_dir.exists():
        logger.warning(f'Device directory {device_dir} already exists.')
        click.echo(f'Device {device} already exists in the database.')
        click.echo('Exiting...')
        sys.exit()
    try:
        device_dir.mkdir()
    except OSError as e:
        logger.error(f'Error trying to create device {e}')
        click.echo('Exiting...')
        sys.exit()

    # Step 4: Save metadata into device_dir
    metadata_path = device_dir / definitions.DEVICE_METADATA_FILE_NAME
    with metadata_path.open('w') as metadata_file:
        json.dump(device_metadata.__dict__, metadata_file, indent=4)
    click.echo(f'Successfully added device {device} to database')
    logger.debug(f'Added device {device} to database {database}. Full path of metadata {metadata_path}')
    logger.info(f'Metadata for {device} {device_metadata.print_attributes()}')