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# 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
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#   http://www.apache.org/licenses/LICENSE-2.0
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# KIND, either express or implied.  See the License for the
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import json
from datetime import datetime as dt

import pendulum
from flask_appbuilder.fieldwidgets import (
    BS3PasswordFieldWidget,
    BS3TextAreaFieldWidget,
    BS3TextFieldWidget,
    Select2Widget,
)
from flask_appbuilder.forms import DynamicForm
from flask_babel import lazy_gettext
from flask_wtf import FlaskForm
from wtforms import widgets
from wtforms.fields import Field, IntegerField, PasswordField, SelectField, StringField, TextAreaField
from wtforms.validators import InputRequired, Optional

from airflow.configuration import conf
from airflow.utils import timezone
from airflow.utils.types import DagRunType
from airflow.www.widgets import (
    AirflowDateTimePickerROWidget,
    AirflowDateTimePickerWidget,
    BS3TextAreaROWidget,
    BS3TextFieldROWidget,
)


class DateTimeWithTimezoneField(Field):
    """A text field which stores a `datetime.datetime` matching a format."""

    widget = widgets.TextInput()

    def __init__(self, label=None, validators=None, datetime_format='%Y-%m-%d %H:%M:%S%Z', **kwargs):
        super().__init__(label, validators, **kwargs)
        self.format = datetime_format
        self.data = None

    def _value(self):
        if self.raw_data:
            return ' '.join(self.raw_data)
        if self.data:
            return self.data.strftime(self.format)
        return ''

    def process_formdata(self, valuelist):
        if not valuelist:
            return
        date_str = ' '.join(valuelist)
        try:
            # Check if the datetime string is in the format without timezone, if so convert it to the
            # default timezone
            if len(date_str) == 19:
                parsed_datetime = dt.strptime(date_str, '%Y-%m-%d %H:%M:%S')
                default_timezone = self._get_default_timezone()
                self.data = default_timezone.convert(parsed_datetime)
            else:
                self.data = pendulum.parse(date_str)
        except ValueError:
            self.data = None
            raise ValueError(self.gettext('Not a valid datetime value'))

    def _get_default_timezone(self):
        current_timezone = conf.get("core", "default_timezone")
        if current_timezone == "system":
            default_timezone = pendulum.local_timezone()
        else:
            default_timezone = pendulum.timezone(current_timezone)
        return default_timezone


class DateTimeForm(FlaskForm):
    """Date filter form needed for task views"""

    execution_date = DateTimeWithTimezoneField("Logical date", widget=AirflowDateTimePickerWidget())


class DateTimeWithNumRunsForm(FlaskForm):
    """
    Date time and number of runs form for tree view, task duration
    and landing times
    """

    base_date = DateTimeWithTimezoneField(
        "Anchor date", widget=AirflowDateTimePickerWidget(), default=timezone.utcnow()
    )
    num_runs = SelectField(
        "Number of runs",
        default=25,
        choices=(
            (5, "5"),
            (25, "25"),
            (50, "50"),
            (100, "100"),
            (365, "365"),
        ),
    )


class DateTimeWithNumRunsWithDagRunsForm(DateTimeWithNumRunsForm):
    """Date time and number of runs and dag runs form for graph and gantt view"""

    execution_date = SelectField("DAG run")


class DagRunEditForm(DynamicForm):
    """Form for editing DAG Run.

    We don't actually want to allow editing, so everything is read-only here.
    """

    dag_id = StringField(lazy_gettext('Dag Id'), widget=BS3TextFieldROWidget())
    start_date = DateTimeWithTimezoneField(lazy_gettext('Start Date'), widget=AirflowDateTimePickerROWidget())
    end_date = DateTimeWithTimezoneField(lazy_gettext('End Date'), widget=AirflowDateTimePickerROWidget())
    run_id = StringField(lazy_gettext('Run Id'), widget=BS3TextFieldROWidget())
    state = StringField(lazy_gettext('State'), widget=BS3TextFieldROWidget())
    execution_date = DateTimeWithTimezoneField(
        lazy_gettext('Logical Date'),
        widget=AirflowDateTimePickerROWidget(),
    )
    conf = TextAreaField(lazy_gettext('Conf'), widget=BS3TextAreaROWidget())

    def populate_obj(self, item):
        """Populates the attributes of the passed obj with data from the form’s fields."""
        super().populate_obj(item)
        item.run_type = DagRunType.from_run_id(item.run_id)
        if item.conf:
            item.conf = json.loads(item.conf)


class TaskInstanceEditForm(DynamicForm):
    """Form for editing TaskInstance"""

    dag_id = StringField(lazy_gettext('Dag Id'), validators=[InputRequired()], widget=BS3TextFieldROWidget())
    task_id = StringField(
        lazy_gettext('Task Id'), validators=[InputRequired()], widget=BS3TextFieldROWidget()
    )
    start_date = DateTimeWithTimezoneField(lazy_gettext('Start Date'), widget=AirflowDateTimePickerROWidget())
    end_date = DateTimeWithTimezoneField(lazy_gettext('End Date'), widget=AirflowDateTimePickerROWidget())
    state = SelectField(
        lazy_gettext('State'),
        choices=(
            ('success', 'success'),
            ('running', 'running'),
            ('failed', 'failed'),
            ('up_for_retry', 'up_for_retry'),
        ),
        widget=Select2Widget(),
        validators=[InputRequired()],
    )
    execution_date = DateTimeWithTimezoneField(
        lazy_gettext('Logical Date'),
        widget=AirflowDateTimePickerROWidget(),
        validators=[InputRequired()],
    )


class ConnectionForm(DynamicForm):
    """Form for editing and adding Connection"""

    conn_id = StringField(
        lazy_gettext('Connection Id'), validators=[InputRequired()], widget=BS3TextFieldWidget()
    )
    description = StringField(lazy_gettext('Description'), widget=BS3TextAreaFieldWidget())
    host = StringField(lazy_gettext('Host'), widget=BS3TextFieldWidget())
    schema = StringField(lazy_gettext('Schema'), widget=BS3TextFieldWidget())
    login = StringField(lazy_gettext('Login'), widget=BS3TextFieldWidget())
    password = PasswordField(lazy_gettext('Password'), widget=BS3PasswordFieldWidget())
    port = IntegerField(lazy_gettext('Port'), validators=[Optional()], widget=BS3TextFieldWidget())
    extra = TextAreaField(lazy_gettext('Extra'), widget=BS3TextAreaFieldWidget())
