# Copyright (C) 2005-2024 Splunk Inc. All Rights Reserved.

import json
from itsi_py3 import _
from ITOA.itoa_common import validate_json


class EntityDataDrilldownValidationException(Exception):
    pass


class EntityDataDrilldown(object):
    """
    EntityDataDrilldown - an entity data drilldown is used to associated entity with raw data
    """

    valid_types = ['metrics', 'events']

    def __init__(self, title, type, static_filter, entity_field_filter):
        """
        Initialize an EntityDataDrilldown object

        @type title: str
        @param title: name of the drilldown

        @type type: str
        @param type: corresponds to the raw data type in splunk (i.e. metrics or events)

        @type: static_filter: dict
        @param static_filter: json filter used to find subset of data that might be associated based on some static information

        @type entity_field_filter: dict
        @param entity_field_filter: json filter to be constructed using entity's alias information
        """
        self.title = title
        self.type = type
        self.static_filter = DataDrilldownFilter.from_json(static_filter)
        self.entity_field_filter = DataDrilldownFilter.from_json(entity_field_filter)

    @classmethod
    def validate(cls, log_prefix, json_data):
        """
        Validate if input json represents a valid entity data drilldown

        @type log_prefix: str
        @param log_prefix: prefix for log message

        @param json_data: data drilldown in json format
        @type json_data: dict

        @return: None
        """
        validate_json(log_prefix, json_data)
        cls._validate_type(log_prefix, json_data.get('type'))
        cls._validate_data_filter(log_prefix, json_data.get('static_filter'), json_data.get('entity_field_filter'))

    @classmethod
    def _validate_type(cls, log_prefix, drilldown_type):
        """
        Validate if the input type for entity data drilldown is valid

        @type log_prefix: str
        @param log_prefix: prefix for log message

        @type drilldown_type: str
        @param drilldown_type: drilldown type

        @return: None
        """
        if drilldown_type not in cls.valid_types:
            raise EntityDataDrilldownValidationException(
                log_prefix + _('Invalid data type for entity data drilldown - "%s". Must be one of %s') % (
                    drilldown_type,
                    ', '.join(cls.valid_types)
                )
            )

    @classmethod
    def _validate_data_filter(cls, log_prefix, static_filter, entity_field_filter):
        """
        Validate both static filter and entity field filter

        @type log_prefix: str
        @param log_prefix: prefix for log message

        @type static_filter: dict
        @param static_filter:

        @type entity_field_filter: dict
        @param entity_field_filter:

        @return: None
        """
        if not static_filter or not entity_field_filter:
            raise EntityDataDrilldownValidationException(log_prefix + _('static_filter and entity_field_filter cannot be empty'))

        DataDrilldownFilter.validate_data_filter_json(log_prefix, static_filter)
        DataDrilldownFilter.validate_data_filter_json(log_prefix, entity_field_filter)

    def build_data_drilldown_filter(self, entity):
        """
        construct data filter based on the entity information from input.

        @type entity: dict
        @param entity: entity information

        @rtype: dict
        @return: A data drilldown filter
        """
        drilldown_filter = BooleanFilter(
            type='and',
            filters=[self.static_filter, self.entity_field_filter]
        )
        filter_json = drilldown_filter.to_json(reference_entity=entity)
        filter_json_with_metadata = {
            'data_drilldown_title': self.title,
            'type': self.type,
            'filter': filter_json
        }
        return filter_json_with_metadata


class DataDrilldownFilter(object):
    """
    DataDrilldownFilter - represents a data drilldown filter which can be used to filter raw data.
    """

    def __init__(self, type):
        self.type = type

    @staticmethod
    def validate_data_filter_json(log_prefix, json_data):
        """
        Helper method to perform recursive validation on filters to check the necessary fields and structure

        @type log_prefix: str
        @param log_prefix: prefix for log message

        @type json_data: dict
        @param json_data: filter data in json format

        @return: None
        """
        f_type = json_data.get('type')
        if f_type in BasicFilter.ALLOWED_TYPES:
            BasicFilter.validate(log_prefix, json_data)
        elif f_type in BooleanFilter.ALLOWED_TYPES:
            BooleanFilter.validate(log_prefix, json_data)
        elif f_type in EntityFieldFilter.ALLOWED_TYPES:
            EntityFieldFilter.validate(log_prefix, json_data)
        else:
            raise EntityDataDrilldownValidationException(log_prefix + _('Invalid filter type found "%s"') % f_type)

    @staticmethod
    def from_json(json_data):
        """
        Deserialize input json data into an DataDrilldownFilter object

        @type json_data: dict
        @param json_data:

        @rtype: DataDrilldownFilter
        @return: A DataDrilldownFilter instance
        """
        params = json.loads(json_data) if isinstance(json_data, str) else json_data
        filter_type = params.get('type')
        if filter_type in BasicFilter.ALLOWED_TYPES:
            return BasicFilter(**params)
        elif filter_type in EntityFieldFilter.ALLOWED_TYPES:
            return EntityFieldFilter(**params)
        elif filter_type in BooleanFilter.ALLOWED_TYPES:
            return BooleanFilter(
                type=filter_type,
                filters=[DataDrilldownFilter.from_json(data) for data in json_data.get('filters', [])]
            )

    def to_json(self, **kwargs):
        """
        Serialize a DataDrilldownFilter object into its JSON format

        @type kwargs: dict
        @param kwargs: Any additional information required for serialization in key value format

        @return: json
        """
        raise NotImplementedError()


class BasicFilter(DataDrilldownFilter):
    """
    BasicFilter - equivalent a field=value filter OR field!=value filter based on its type
    """
    ALLOWED_TYPES = ['include', 'exclude']
    REQUIRED_FIELDS = ['type', 'values', 'field']

    def __init__(self, type, field, values):
        super(BasicFilter, self).__init__(type)
        self.type = type
        self.field = field
        self.values = values

    @classmethod
    def validate(cls, log_prefix, json_data):
        if not all([f in json_data for f in cls.REQUIRED_FIELDS]):
            raise EntityDataDrilldownValidationException(log_prefix + _('Missing field in basic filter, must contain %s') % cls.REQUIRED_FIELDS)
        if json_data['type'] not in cls.ALLOWED_TYPES:
            raise EntityDataDrilldownValidationException(log_prefix + _('Invalid type found for basic filter - "%s"') % json_data['type'])
        if not isinstance(json_data['values'], list):
            raise EntityDataDrilldownValidationException(
                log_prefix + _('Invalid type for values field of basic filter, must be list. Found: %s') %
                type(json_data['values']).__name__
            )

    def to_json(self, **kwargs):
        return {
            'type': self.type,
            'field': {'name': self.field},
            'values': self.values
        }


class BooleanFilter(DataDrilldownFilter):
    """
    BooleanFilter - glues BasicFilter and EntityFieldFilter together to express complex boolean logic
    """
    ALLOWED_TYPES = ['or', 'and']
    REQUIRED_FIELDS = ['type', 'filters']

    def __init__(self, type, filters):
        super(BooleanFilter, self).__init__(type)
        self.type = type
        self.filters = filters

    @classmethod
    def validate(cls, log_prefix, json_data):
        if 'filters' not in json_data:
            raise EntityDataDrilldownValidationException(log_prefix + _('Missing field in boolean filter, must contain "filters"'))
        if not isinstance(json_data['filters'], list):
            raise EntityDataDrilldownValidationException(log_prefix + _('filters of a boolean filter must be a list'))
        if json_data['type'] not in cls.ALLOWED_TYPES:
            raise EntityDataDrilldownValidationException(log_prefix + _('Invalid type found for boolean filter - "%s"') % json_data['type'])

        for filter_json in json_data['filters']:
            DataDrilldownFilter.validate_data_filter_json(log_prefix, filter_json)

    def to_json(self, **kwargs):
        return {
            'type': self.type,
            'filters': [f.to_json(**kwargs) for f in self.filters]
        }


class EntityFieldFilter(DataDrilldownFilter):
    """
    EntityFieldFilter - A filter "template" that could be constructed using an entity's alias.
    """
    ALLOWED_TYPES = ['entity']
    REQUIRED_FIELDS = ['type', 'data_field', 'entity_field']

    def __init__(self, type, data_field, entity_field):
        super(EntityFieldFilter, self).__init__(type)
        self.type = type
        self.data_field = data_field
        self.entity_field = entity_field

    @classmethod
    def validate(cls, log_prefix, json_data):
        if not all([f in json_data for f in cls.REQUIRED_FIELDS]):
            raise EntityDataDrilldownValidationException(log_prefix + _('Missing field in entity field filter, must contain %s') % cls.REQUIRED_FIELDS)
        if json_data['type'] not in cls.ALLOWED_TYPES:
            raise EntityDataDrilldownValidationException(log_prefix + _('Invalid type found for entity field filter - "%s"') % json_data['type'])

    def convert_to_basic_filter(self, entity):
        """
        Convert a EntityFieldFilter object to a BasicFilter object based on the input entity information

        @type entity: dict
        @param entity:

        @rtype: BasicFilter
        @return: A BasicFilter instance
        """
        value = entity.get(self.entity_field)
        if not isinstance(value, list):
            value = [value]

        return BasicFilter(
            type='include',
            field=self.data_field,
            values=value
        )

    def to_json(self, **kwargs):
        """
        Convert an EntityFieldFilter object to json, and convert to BasicFilter json if a
        reference entity is passed in

        @type kwargs: dict
        @param kwargs: Any extra information

        @keyword reference_entity: The entity to use to convert to a basic filter

        @rtype: dict
        @return: the EntityFieldFilter instance in json format
        """
        reference_entity = kwargs.get('reference_entity')
        if isinstance(reference_entity, dict):
            return self.convert_to_basic_filter(reference_entity).to_json()
        return {
            'type': self.type,
            'data_field': self.data_field,
            'entity_field': self.entity_field
        }