# Licensed to the Apache Software Foundation (ASF) under one
# or more contributor license agreements.  See the NOTICE file
# distributed with this work for additional information
# regarding copyright ownership.  The ASF licenses this file
# to you under the Apache License, Version 2.0 (the
# "License"); you may not use this file except in compliance
# with the License.  You may obtain a copy of the License at
#
#   http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing,
# software distributed under the License is distributed on an
# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
# KIND, either express or implied.  See the License for the
# specific language governing permissions and limitations
# under the License.

import logging
import os
from typing import Any, Callable, Dict

import wtforms_json
from flask import Flask, redirect
from flask_appbuilder import expose, IndexView
from flask_babel import gettext as __, lazy_gettext as _
from flask_compress import Compress

from superset.connectors.connector_registry import ConnectorRegistry
from superset.extensions import (
    _event_logger,
    APP_DIR,
    appbuilder,
    async_query_manager,
    cache_manager,
    celery_app,
    csrf,
    db,
    feature_flag_manager,
    machine_auth_provider_factory,
    manifest_processor,
    migrate,
    results_backend_manager,
    talisman,
)
from superset.security import SupersetSecurityManager
from superset.typing import FlaskResponse
from superset.utils.core import pessimistic_connection_handling
from superset.utils.log import DBEventLogger, get_event_logger_from_cfg_value

logger = logging.getLogger(__name__)


def create_app() -> Flask:
    app = Flask(__name__)

    try:
        # Allow user to override our config completely
        config_module = os.environ.get("SUPERSET_CONFIG", "superset.config")
        app.config.from_object(config_module)

        app_initializer = app.config.get("APP_INITIALIZER", SupersetAppInitializer)(app)
        app_initializer.init_app()

        return app

    # Make sure that bootstrap errors ALWAYS get logged
    except Exception as ex:
        logger.exception("Failed to create app")
        raise ex


class SupersetIndexView(IndexView):
    @expose("/")
    def index(self) -> FlaskResponse:
        return redirect("/superset/welcome/")


class SupersetAppInitializer:
    def __init__(self, app: Flask) -> None:
        super().__init__()

        self.flask_app = app
        self.config = app.config
        self.manifest: Dict[Any, Any] = {}

    def pre_init(self) -> None:
        """
        Called before all other init tasks are complete
        """
        wtforms_json.init()

        if not os.path.exists(self.config["DATA_DIR"]):
            os.makedirs(self.config["DATA_DIR"])

    def post_init(self) -> None:
        """
        Called after any other init tasks
        """

    def configure_celery(self) -> None:
        celery_app.config_from_object(self.config["CELERY_CONFIG"])
        celery_app.set_default()
        flask_app = self.flask_app

        # Here, we want to ensure that every call into Celery task has an app context
        # setup properly
        task_base = celery_app.Task

        class AppContextTask(task_base):  # type: ignore
            # pylint: disable=too-few-public-methods
            abstract = True

            # Grab each call into the task and set up an app context
            def __call__(self, *args: Any, **kwargs: Any) -> Any:
                with flask_app.app_context():  # type: ignore
                    return task_base.__call__(self, *args, **kwargs)

        celery_app.Task = AppContextTask

    def init_views(self) -> None:
        #
        # We're doing local imports, as several of them import
        # models which in turn try to import
        # the global Flask app
        #
        # pylint: disable=too-many-locals
        # pylint: disable=too-many-statements
        # pylint: disable=too-many-branches
        from superset.annotation_layers.api import AnnotationLayerRestApi
        from superset.annotation_layers.annotations.api import AnnotationRestApi
        from superset.async_events.api import AsyncEventsRestApi
        from superset.cachekeys.api import CacheRestApi
        from superset.charts.api import ChartRestApi
        from superset.connectors.druid.views import (
            Druid,
            DruidClusterModelView,
            DruidColumnInlineView,
            DruidDatasourceModelView,
            DruidMetricInlineView,
        )
        from superset.connectors.sqla.views import (
            RowLevelSecurityFiltersModelView,
            SqlMetricInlineView,
            TableColumnInlineView,
            TableModelView,
        )
        from superset.css_templates.api import CssTemplateRestApi
        from superset.dashboards.api import DashboardRestApi
        from superset.databases.api import DatabaseRestApi
        from superset.datasets.api import DatasetRestApi
        from superset.datasets.columns.api import DatasetColumnsRestApi
        from superset.datasets.metrics.api import DatasetMetricRestApi
        from superset.queries.api import QueryRestApi
        from superset.security.api import SecurityRestApi
        from superset.queries.saved_queries.api import SavedQueryRestApi
        from superset.reports.api import ReportScheduleRestApi
        from superset.reports.logs.api import ReportExecutionLogRestApi
        from superset.views.access_requests import AccessRequestsModelView
        from superset.views.alerts import (
            AlertLogModelView,
            AlertModelView,
            AlertObservationModelView,
            AlertView,
            ReportView,
        )
        from superset.views.annotations import (
            AnnotationLayerModelView,
            AnnotationModelView,
        )
        from superset.views.api import Api
        from superset.views.chart.views import SliceAsync, SliceModelView
        from superset.views.core import Superset
        from superset.views.css_templates import (
            CssTemplateAsyncModelView,
            CssTemplateModelView,
        )
        from superset.views.dashboard.views import (
            Dashboard,
            DashboardModelView,
            DashboardModelViewAsync,
        )
        from superset.views.database.views import (
            CsvToDatabaseView,
            DatabaseView,
            ExcelToDatabaseView,
        )
        from superset.views.datasource import Datasource
        from superset.views.dynamic_plugins import DynamicPluginsView
        from superset.views.key_value import KV
        from superset.views.log.api import LogRestApi
        from superset.views.log.views import LogModelView
        from superset.views.redirects import R
        from superset.views.schedules import (
            DashboardEmailScheduleView,
            SliceEmailScheduleView,
        )
        from superset.views.sql_lab import (
            SavedQueryView,
            SavedQueryViewApi,
            SqlLab,
            TableSchemaView,
            TabStateView,
        )
        from superset.views.tags import TagView

        #
        # Setup API views
        #
        appbuilder.add_api(AnnotationRestApi)
        appbuilder.add_api(AnnotationLayerRestApi)
        appbuilder.add_api(AsyncEventsRestApi)
        appbuilder.add_api(CacheRestApi)
        appbuilder.add_api(ChartRestApi)
        appbuilder.add_api(CssTemplateRestApi)
        appbuilder.add_api(DashboardRestApi)
        appbuilder.add_api(DatabaseRestApi)
        appbuilder.add_api(DatasetRestApi)
        appbuilder.add_api(DatasetColumnsRestApi)
        appbuilder.add_api(DatasetMetricRestApi)
        appbuilder.add_api(QueryRestApi)
        appbuilder.add_api(SavedQueryRestApi)
        if feature_flag_manager.is_feature_enabled("ALERT_REPORTS"):
            appbuilder.add_api(ReportScheduleRestApi)
            appbuilder.add_api(ReportExecutionLogRestApi)
        #
        # Setup regular views
        #
        if appbuilder.app.config["LOGO_TARGET_PATH"]:
            appbuilder.add_link(
                "Home", label=__("Home"), href="/superset/welcome/",
            )
        appbuilder.add_view(
            AnnotationLayerModelView,
            "Annotation Layers",
            label=__("Annotation Layers"),
            icon="fa-comment",
            category="Manage",
            category_label=__("Manage"),
            category_icon="",
        )
        appbuilder.add_view(
            DatabaseView,
            "Databases",
            label=__("Databases"),
            icon="fa-database",
            category="Data",
            category_label=__("Data"),
            category_icon="fa-database",
        )
        appbuilder.add_link(
            "Datasets",
            label=__("Datasets"),
            href="/tablemodelview/list/",
            icon="fa-table",
            category="Data",
            category_label=__("Data"),
            category_icon="fa-table",
        )
        appbuilder.add_separator("Data")
        appbuilder.add_view(
            SliceModelView,
            "Charts",
            label=__("Charts"),
            icon="fa-bar-chart",
            category="",
            category_icon="",
        )
        appbuilder.add_view(
            DashboardModelView,
            "Dashboards",
            label=__("Dashboards"),
            icon="fa-dashboard",
            category="",
            category_icon="",
        )
        if feature_flag_manager.is_feature_enabled("DYNAMIC_PLUGINS"):
            appbuilder.add_view(
                DynamicPluginsView,
                "Plugins",
                label=__("Plugins"),
                category="Manage",
                category_label=__("Manage"),
                icon="fa-puzzle-piece",
            )
        appbuilder.add_view(
            CssTemplateModelView,
            "CSS Templates",
            label=__("CSS Templates"),
            icon="fa-css3",
            category="Manage",
            category_label=__("Manage"),
            category_icon="",
        )
        if feature_flag_manager.is_feature_enabled("ROW_LEVEL_SECURITY"):
            appbuilder.add_view(
                RowLevelSecurityFiltersModelView,
                "Row Level Security",
                label=__("Row level security"),
                category="Security",
                category_label=__("Security"),
                icon="fa-lock",
            )

        #
        # Setup views with no menu
        #
        appbuilder.add_view_no_menu(Api)
        appbuilder.add_view_no_menu(CssTemplateAsyncModelView)
        appbuilder.add_view_no_menu(CsvToDatabaseView)
        appbuilder.add_view_no_menu(ExcelToDatabaseView)
        appbuilder.add_view_no_menu(Dashboard)
        appbuilder.add_view_no_menu(DashboardModelViewAsync)
        appbuilder.add_view_no_menu(Datasource)

        if feature_flag_manager.is_feature_enabled("KV_STORE"):
            appbuilder.add_view_no_menu(KV)

        appbuilder.add_view_no_menu(R)
        appbuilder.add_view_no_menu(SavedQueryView)
        appbuilder.add_view_no_menu(SavedQueryViewApi)
        appbuilder.add_view_no_menu(SliceAsync)
        appbuilder.add_view_no_menu(SqlLab)
        appbuilder.add_view_no_menu(SqlMetricInlineView)
        appbuilder.add_view_no_menu(AnnotationModelView)
        appbuilder.add_view_no_menu(Superset)
        appbuilder.add_view_no_menu(TableColumnInlineView)
        appbuilder.add_view_no_menu(TableModelView)
        appbuilder.add_view_no_menu(TableSchemaView)
        appbuilder.add_view_no_menu(TabStateView)

        if feature_flag_manager.is_feature_enabled("TAGGING_SYSTEM"):
            appbuilder.add_view_no_menu(TagView)

        #
        # Add links
        #
        if not feature_flag_manager.is_feature_enabled("VERSIONED_EXPORT"):
            appbuilder.add_link(
                "Import Dashboards",
                label=__("Import Dashboards"),
                href="/superset/import_dashboards/",
                icon="fa-cloud-upload",
                category="Manage",
                category_label=__("Manage"),
                category_icon="fa-wrench",
            )
        appbuilder.add_link(
            "SQL Editor",
            label=_("SQL Editor"),
            href="/superset/sqllab/",
            category_icon="fa-flask",
            icon="fa-flask",
            category="SQL Lab",
            category_label=__("SQL Lab"),
        )
        appbuilder.add_link(
            __("Saved Queries"),
            href="/savedqueryview/list/",
            icon="fa-save",
            category="SQL Lab",
        )
        appbuilder.add_link(
            "Query Search",
            label=_("Query History"),
            href="/superset/sqllab/history/",
            icon="fa-search",
            category_icon="fa-flask",
            category="SQL Lab",
            category_label=__("SQL Lab"),
        )
        if self.config["CSV_EXTENSIONS"].intersection(
            self.config["ALLOWED_EXTENSIONS"]
        ):
            appbuilder.add_link(
                "Upload a CSV",
                label=__("Upload a CSV"),
                href="/csvtodatabaseview/form",
                icon="fa-upload",
                category="Data",
                category_label=__("Data"),
                category_icon="fa-wrench",
            )
        try:
            import xlrd  # pylint: disable=unused-import

            if self.config["EXCEL_EXTENSIONS"].intersection(
                self.config["ALLOWED_EXTENSIONS"]
            ):
                appbuilder.add_link(
                    "Upload Excel",
                    label=__("Upload Excel"),
                    href="/exceltodatabaseview/form",
                    icon="fa-upload",
                    category="Data",
                    category_label=__("Data"),
                    category_icon="fa-wrench",
                )
        except ImportError:
            pass

        #
        # Conditionally setup log views
        #
        if self.config["FAB_ADD_SECURITY_VIEWS"] and self.config["SUPERSET_LOG_VIEW"]:
            appbuilder.add_api(LogRestApi)
            appbuilder.add_view(
                LogModelView,
                "Action Log",
                label=__("Action Log"),
                category="Security",
                category_label=__("Security"),
                icon="fa-list-ol",
            )
        appbuilder.add_api(SecurityRestApi)
        #
        # Conditionally setup email views
        #
        if self.config["ENABLE_SCHEDULED_EMAIL_REPORTS"]:
            logging.warning(
                "ENABLE_SCHEDULED_EMAIL_REPORTS "
                "is deprecated and will be removed in version 2.0.0"
            )
            appbuilder.add_separator("Manage")
            appbuilder.add_view(
                DashboardEmailScheduleView,
                "Dashboard Email Schedules",
                label=__("Dashboard Emails"),
                category="Manage",
                category_label=__("Manage"),
                icon="fa-search",
            )
            appbuilder.add_view(
                SliceEmailScheduleView,
                "Chart Emails",
                label=__("Chart Email Schedules"),
                category="Manage",
                category_label=__("Manage"),
                icon="fa-search",
            )

        if self.config["ENABLE_ALERTS"]:
            logging.warning(
                "ENABLE_ALERTS is deprecated and will be removed in version 2.0.0"
            )
            appbuilder.add_view(
                AlertModelView,
                "Alerts",
                label=__("Alerts"),
                category="Manage",
                category_label=__("Manage"),
                icon="fa-exclamation-triangle",
            )
            appbuilder.add_view_no_menu(AlertLogModelView)
            appbuilder.add_view_no_menu(AlertObservationModelView)

        if feature_flag_manager.is_feature_enabled("ALERT_REPORTS"):
            appbuilder.add_view(
                AlertView,
                "Alerts & Report",
                label=__("Alerts & Reports"),
                category="Manage",
                category_label=__("Manage"),
                icon="fa-exclamation-triangle",
            )
            appbuilder.add_view_no_menu(ReportView)

        #
        # Conditionally add Access Request Model View
        #
        if self.config["ENABLE_ACCESS_REQUEST"]:
            appbuilder.add_view(
                AccessRequestsModelView,
                "Access requests",
                label=__("Access requests"),
                category="Security",
                category_label=__("Security"),
                icon="fa-table",
            )

        #
        # Conditionally setup Druid Views
        #
        if self.config["DRUID_IS_ACTIVE"]:
            appbuilder.add_separator("Data")
            appbuilder.add_view(
                DruidDatasourceModelView,
                "Druid Datasources",
                label=__("Druid Datasources"),
                category="Data",
                category_label=__("Data"),
                icon="fa-cube",
            )
            appbuilder.add_view(
                DruidClusterModelView,
                name="Druid Clusters",
                label=__("Druid Clusters"),
                icon="fa-cubes",
                category="Data",
                category_label=__("Data"),
                category_icon="fa-database",
            )
            appbuilder.add_view_no_menu(DruidMetricInlineView)
            appbuilder.add_view_no_menu(DruidColumnInlineView)
            appbuilder.add_view_no_menu(Druid)

            if self.config["DRUID_METADATA_LINKS_ENABLED"]:
                appbuilder.add_link(
                    "Scan New Datasources",
                    label=__("Scan New Datasources"),
                    href="/druid/scan_new_datasources/",
                    category="Data",
                    category_label=__("Data"),
                    category_icon="fa-database",
                    icon="fa-refresh",
                )
                appbuilder.add_link(
                    "Refresh Druid Metadata",
                    label=__("Refresh Druid Metadata"),
                    href="/druid/refresh_datasources/",
                    category="Data",
                    category_label=__("Data"),
                    category_icon="fa-database",
                    icon="fa-cog",
                )
            appbuilder.add_separator("Data")

    def init_app_in_ctx(self) -> None:
        """
        Runs init logic in the context of the app
        """
        self.configure_feature_flags()
        self.configure_fab()
        self.configure_url_map_converters()
        self.configure_data_sources()
        self.configure_auth_provider()
        self.configure_async_queries()

        # Hook that provides administrators a handle on the Flask APP
        # after initialization
        flask_app_mutator = self.config["FLASK_APP_MUTATOR"]
        if flask_app_mutator:
            flask_app_mutator(self.flask_app)

        self.init_views()

    def init_app(self) -> None:
        """
        Main entry point which will delegate to other methods in
        order to fully init the app
        """
        self.pre_init()
        self.setup_db()
        self.configure_celery()
        self.setup_event_logger()
        self.setup_bundle_manifest()
        self.register_blueprints()
        self.configure_wtf()
        self.configure_logging()
        self.configure_middlewares()
        self.configure_cache()

        with self.flask_app.app_context():  # type: ignore
            self.init_app_in_ctx()

        self.post_init()

    def configure_auth_provider(self) -> None:
        machine_auth_provider_factory.init_app(self.flask_app)

    def setup_event_logger(self) -> None:
        _event_logger["event_logger"] = get_event_logger_from_cfg_value(
            self.flask_app.config.get("EVENT_LOGGER", DBEventLogger())
        )

    def configure_data_sources(self) -> None:
        # Registering sources
        module_datasource_map = self.config["DEFAULT_MODULE_DS_MAP"]
        module_datasource_map.update(self.config["ADDITIONAL_MODULE_DS_MAP"])
        ConnectorRegistry.register_sources(module_datasource_map)

    def configure_cache(self) -> None:
        cache_manager.init_app(self.flask_app)
        results_backend_manager.init_app(self.flask_app)

    def configure_feature_flags(self) -> None:
        feature_flag_manager.init_app(self.flask_app)

    def configure_fab(self) -> None:
        if self.config["SILENCE_FAB"]:
            logging.getLogger("flask_appbuilder").setLevel(logging.ERROR)

        custom_sm = self.config["CUSTOM_SECURITY_MANAGER"] or SupersetSecurityManager
        if not issubclass(custom_sm, SupersetSecurityManager):
            raise Exception(
                """Your CUSTOM_SECURITY_MANAGER must now extend SupersetSecurityManager,
                 not FAB's security manager.
                 See [4565] in UPDATING.md"""
            )

        appbuilder.indexview = SupersetIndexView
        appbuilder.base_template = "superset/base.html"
        appbuilder.security_manager_class = custom_sm
        appbuilder.init_app(self.flask_app, db.session)

    def configure_url_map_converters(self) -> None:
        #
        # Doing local imports here as model importing causes a reference to
        # app.config to be invoked and we need the current_app to have been setup
        #
        from superset.utils.url_map_converters import (
            ObjectTypeConverter,
            RegexConverter,
        )

        self.flask_app.url_map.converters["regex"] = RegexConverter
        self.flask_app.url_map.converters["object_type"] = ObjectTypeConverter

    def configure_middlewares(self) -> None:
        if self.config["ENABLE_CORS"]:
            from flask_cors import CORS

            CORS(self.flask_app, **self.config["CORS_OPTIONS"])

        if self.config["ENABLE_PROXY_FIX"]:
            from werkzeug.middleware.proxy_fix import ProxyFix

            self.flask_app.wsgi_app = ProxyFix(  # type: ignore
                self.flask_app.wsgi_app, **self.config["PROXY_FIX_CONFIG"]
            )

        if self.config["ENABLE_CHUNK_ENCODING"]:

            class ChunkedEncodingFix:  # pylint: disable=too-few-public-methods
                def __init__(self, app: Flask) -> None:
                    self.app = app

                def __call__(
                    self, environ: Dict[str, Any], start_response: Callable[..., Any]
                ) -> Any:
                    # Setting wsgi.input_terminated tells werkzeug.wsgi to ignore
                    # content-length and read the stream till the end.
                    if environ.get("HTTP_TRANSFER_ENCODING", "").lower() == "chunked":
                        environ["wsgi.input_terminated"] = True
                    return self.app(environ, start_response)

            self.flask_app.wsgi_app = ChunkedEncodingFix(  # type: ignore
                self.flask_app.wsgi_app  # type: ignore
            )

        if self.config["UPLOAD_FOLDER"]:
            try:
                os.makedirs(self.config["UPLOAD_FOLDER"])
            except OSError:
                pass

        for middleware in self.config["ADDITIONAL_MIDDLEWARE"]:
            self.flask_app.wsgi_app = middleware(  # type: ignore
                self.flask_app.wsgi_app
            )

        # Flask-Compress
        Compress(self.flask_app)

        if self.config["TALISMAN_ENABLED"]:
            talisman.init_app(self.flask_app, **self.config["TALISMAN_CONFIG"])

    def configure_logging(self) -> None:
        self.config["LOGGING_CONFIGURATOR"].configure_logging(
            self.config, self.flask_app.debug
        )

    def setup_db(self) -> None:
        db.init_app(self.flask_app)

        with self.flask_app.app_context():  # type: ignore
            pessimistic_connection_handling(db.engine)

        migrate.init_app(self.flask_app, db=db, directory=APP_DIR + "/migrations")

    def configure_wtf(self) -> None:
        if self.config["WTF_CSRF_ENABLED"]:
            csrf.init_app(self.flask_app)
            csrf_exempt_list = self.config["WTF_CSRF_EXEMPT_LIST"]
            for ex in csrf_exempt_list:
                csrf.exempt(ex)

    def configure_async_queries(self) -> None:
        if feature_flag_manager.is_feature_enabled("GLOBAL_ASYNC_QUERIES"):
            async_query_manager.init_app(self.flask_app)

    def register_blueprints(self) -> None:
        for bp in self.config["BLUEPRINTS"]:
            try:
                logger.info("Registering blueprint: %s", bp.name)
                self.flask_app.register_blueprint(bp)
            except Exception:  # pylint: disable=broad-except
                logger.exception("blueprint registration failed")

    def setup_bundle_manifest(self) -> None:
        manifest_processor.init_app(self.flask_app)