"""
Class used to parse and update template when application-insights is enabled
"""
import logging
from typing import Any

from ruamel.yaml import YAML
from ruamel.yaml.comments import CommentedMap
from ruamel.yaml.representer import RoundTripRepresenter

from samcli.lib.init.template_modifiers.cli_template_modifier import TemplateModifier
from samcli.lib.utils.resources import AWS_APPLICATION_INSIGHTS, AWS_RESOURCE_GROUP

LOG = logging.getLogger(__name__)


class ApplicationInsightsTemplateModifier(TemplateModifier):
    TYPE_KEY = "Type"
    RESOURCES_KEY = "Resources"
    PROPERTIES_KEY = "Properties"
    NAME_KEY = "Name"
    RESOURCE_QUERY_KEY = "ResourceQuery"
    RESOURCE_GROUP_NAME_KEY = "ResourceGroupName"
    AUTO_CONFIG_ENABLED_KEY = "AutoConfigurationEnabled"
    DEPENDS_ON_KEY = "DependsOn"
    CFN_STACK_TYPE = "CLOUDFORMATION_STACK_1_0"
    RESOURCE_GROUP_REF = "ApplicationResourceGroup"
    APPLICATION_INSIGHTS_REF = "ApplicationInsightsMonitoring"
    AUTO_CONFIG_VALUE = "true"
    RESOURCE_GROUP_NAME = {"Fn::Sub": "ApplicationInsights-SAM-${AWS::StackName}"}

    # set ignore aliases to true. This configuration avoids usage yaml aliases which is not parsed by CloudFormation.
    class NonAliasingRTRepresenter(RoundTripRepresenter):
        def ignore_aliases(self, data):
            return True

    def __init__(self, location):
        self.yaml = YAML()
        self.yaml.Representer = ApplicationInsightsTemplateModifier.NonAliasingRTRepresenter
        super().__init__(location)

    def _get_template(self) -> Any:
        with open(self.template_location) as file:
            return self.yaml.load(file)

    def _update_template_fields(self):
        """
        Add new resources to SAM template
        """
        self._add_app_insights_monitoring_section()

    def _add_app_insights_monitoring_section(self):
        resourceGroup = {
            self.TYPE_KEY: AWS_RESOURCE_GROUP,
            self.PROPERTIES_KEY: {
                self.NAME_KEY: self.RESOURCE_GROUP_NAME,
                self.RESOURCE_QUERY_KEY: {self.TYPE_KEY: self.CFN_STACK_TYPE},
            },
        }

        appInsightsApplication = {
            self.TYPE_KEY: AWS_APPLICATION_INSIGHTS,
            self.PROPERTIES_KEY: {
                self.RESOURCE_GROUP_NAME_KEY: {"Ref": self.RESOURCE_GROUP_REF},
                self.AUTO_CONFIG_ENABLED_KEY: self.AUTO_CONFIG_VALUE,
            },
        }

        self.template[self.RESOURCES_KEY][self.RESOURCE_GROUP_REF] = CommentedMap(resourceGroup)
        self.template[self.RESOURCES_KEY][self.APPLICATION_INSIGHTS_REF] = CommentedMap(appInsightsApplication)

    def _print_sanity_check_error(self):
        link = "https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/cloudwatch-application-insights.html"
        message = (
            f"Warning: Unable to add Application Insights monitoring to the application."
            f"\nTo learn more about Application Insights, visit {link}"
        )
        LOG.warning(message)

    def _write(self, template: list):
        """
        write generated template into SAM template

        Parameters
        ----------
        template : list
            array with updated template data
        """
        with open(self.template_location, "w") as file:
            self.yaml.dump(self.template, file)