"""
Module for parsing configuration from the top level config.py file
"""
from pathlib import Path
from importlib import util
from os import environ
from logging import getLogger

logger = getLogger(__name__)

# PLEASE NOTE: This is a sample config file. Please do NOT make any edits in this file!
# You should create your own config.py and it will overwrite the default config.

DEFAULT_CONFIG = {
    "templates_config_context": False,
    "templates_config_context_overrule": False,
    "template_cf": "zabbix_template",
    "device_cf": "zabbix_hostid",
    "clustering": False,
    "create_hostgroups": True,
    "create_journal": False,
    "sync_vms": False,
    "vm_hostgroup_format": "cluster_type/cluster/role",
    "full_proxy_sync": False,
    "zabbix_device_removal": ["Decommissioning", "Inventory"],
    "zabbix_device_disable": ["Offline", "Planned", "Staged", "Failed"],
    "hostgroup_format": "site/manufacturer/role",
    "traverse_regions": False,
    "traverse_site_groups": False,
    "nb_device_filter": {"name__n": "null"},
    "nb_vm_filter": {"name__n": "null"},
    "inventory_mode": "disabled",
    "inventory_sync": False,
    "device_inventory_map": {
        "asset_tag": "asset_tag",
        "virtual_chassis/name": "chassis",
        "status/label": "deployment_status",
        "location/name": "location",
        "latitude": "location_lat",
        "longitude": "location_lon",
        "comments": "notes",
        "name": "name",
        "rack/name": "site_rack",
        "serial": "serialno_a",
        "device_type/model": "type",
        "device_type/manufacturer/name": "vendor",
        "oob_ip/address": "oob_ip"
    },
    "vm_inventory_map": {
        "status/label": "deployment_status",
        "comments": "notes",
        "name": "name"
    },
    "usermacro_sync": False,
    "device_usermacro_map": {
        "serial": "{$HW_SERIAL}",
        "role/name": "{$DEV_ROLE}",
        "url": "{$NB_URL}",
        "id": "{$NB_ID}"
    },
    "vm_usermacro_map": {
        "memory": "{$TOTAL_MEMORY}",
        "role/name": "{$DEV_ROLE}",
        "url": "{$NB_URL}",
        "id": "{$NB_ID}"
    },
    "tag_sync": False,
    "tag_lower": True,
    "tag_name": 'NetBox',
    "tag_value": "name",
    "device_tag_map": {
        "site/name": "site",
        "rack/name": "rack",
        "platform/name": "target"
    },
    "vm_tag_map": {
        "site/name": "site",
        "cluster/name": "cluster",
        "platform/name": "target"
    }
}


def load_config():
    """Returns combined config from all sources"""
    # Overwrite default config with config.py
    conf = load_config_file(config_default=DEFAULT_CONFIG)
    # Overwrite default config and config.py with environment variables
    for key in conf:
        value_setting = load_env_variable(key)
        if value_setting is not None:
            conf[key] = value_setting
    return conf


def load_env_variable(config_environvar):
    """Returns config from environment variable"""
    prefix = "NBZX_"
    config_environvar = prefix + config_environvar.upper()
    if config_environvar in environ:
        return environ[config_environvar]
    return None


def load_config_file(config_default, config_file="config.py"):
    """Returns config from config.py file"""
    # Check if config.py exists and load it
    # If it does not exist, return the default config
    config_path = Path(config_file)
    if config_path.exists():
        dconf = config_default.copy()
        # Dynamically import the config module
        spec = util.spec_from_file_location("config", config_path)
        config_module = util.module_from_spec(spec)
        spec.loader.exec_module(config_module)
        # Update DEFAULT_CONFIG with variables from the config module
        for key in dconf:
            if hasattr(config_module, key):
                dconf[key] = getattr(config_module, key)
        return dconf
    return config_default