from dataclasses import dataclass, field
from datetime import datetime
from enum import Enum
from typing import Optional

from flet.controls.base_control import control
from flet.controls.control_event import (
    ControlEventHandler,
    Event,
    EventHandler,
)
from flet.controls.dialog_control import DialogControl
from flet.controls.duration import DateTimeValue
from flet.controls.material.textfield import KeyboardType
from flet.controls.padding import Padding, PaddingValue
from flet.controls.types import (
    ColorValue,
    IconData,
    Locale,
)

__all__ = [
    "DatePicker",
    "DatePickerEntryMode",
    "DatePickerEntryModeChangeEvent",
    "DatePickerMode",
]


class DatePickerMode(Enum):
    """Initial display of a calendar date picker."""

    DAY = "day"
    """Choosing a month and day."""

    YEAR = "year"
    """Choosing a year."""


class DatePickerEntryMode(Enum):
    """Mode of date entry method for the date picker dialog."""

    CALENDAR = "calendar"
    """
    User picks a date from calendar grid.

    Can switch to [`INPUT`][(c).] by activating a mode button in the dialog.
    """

    INPUT = "input"
    """
    User can input the date by typing it into a text field.

    Can switch to [`CALENDAR`][(c).] by activating a mode button in the dialog.
    """

    CALENDAR_ONLY = "calendarOnly"
    """
    User can only pick a date from calendar grid.

    There is no user interface to switch to another mode.
    """

    INPUT_ONLY = "inputOnly"
    """
    User can only input the date by typing it into a text field.

    There is no user interface to switch to another mode.
    """


@dataclass
class DatePickerEntryModeChangeEvent(Event["DatePicker"]):
    """Event fired when the [`DatePicker`][flet.] entry mode is changed."""

    entry_mode: DatePickerEntryMode
    """The new date picker entry mode."""


@control("DatePicker")
class DatePicker(DialogControl):
    """
    A Material-style date picker dialog.

    It can be opened by calling [`Page.show_dialog()`][flet.Page.show_dialog] method.

    Depending on the [`entry_mode`][(c).], it will show either a Calendar
    or an Input (TextField) for picking a date.
    """

    value: Optional[DateTimeValue] = None
    """
    The selected date that the picker should display.

    Defaults to [`current_date`][(c).].
    """

    modal: bool = False
    """
    Whether this date picker cannot be dismissed by clicking the area outside of it.
    """

    first_date: DateTimeValue = field(
        default_factory=lambda: datetime(year=1900, month=1, day=1)
    )
    """
    The earliest allowable date that the user can select.

    Defaults to `January 1, 1900`.
    """

    last_date: DateTimeValue = field(
        default_factory=lambda: datetime(year=2050, month=1, day=1)
    )
    """
    The latest allowable date that the user can select.

    Defaults to `January 1, 2050`.
    """

    current_date: DateTimeValue = field(default_factory=lambda: datetime.now())
    """
    The date representing today. It will be highlighted in the day grid.
    """

    locale: Optional[Locale] = None
    """
    The locale for this date picker dialog. It is intended for (rare) cases where this \
    dialog should be localized differently from the rest of the page.

    It overrides the locale used by the page (see [`Page.locale_configuration`][flet.]),
    but does not participate in page-level locale resolution.

    If set to `None` (the default) or an inexistent/unsupported locale,
    the [`current_locale`][flet.LocaleConfiguration.] of the
    [`Page.locale_configuration`][flet.] is used as fallback.
    """

    keyboard_type: KeyboardType = KeyboardType.DATETIME
    """
    The type of keyboard to use for editing the text.
    """

    date_picker_mode: DatePickerMode = DatePickerMode.DAY
    """
    Initial display mode of this picker.
    """

    entry_mode: DatePickerEntryMode = DatePickerEntryMode.CALENDAR
    """
    The initial mode of date entry method for the date picker dialog.
    """

    help_text: Optional[str] = None
    """
    The text that is displayed at the top of the header.

    This is used to indicate to the user what they are selecting a date for.

    Defaults to `"Select date"`.
    """

    cancel_text: Optional[str] = None
    """
    The text that is displayed on the cancel button.

    Defaults to `"Cancel"`.
    """

    confirm_text: Optional[str] = None
    """
    The text that is displayed on the confirm button.

    Defaults to `"OK"`.
    """

    error_format_text: Optional[str] = None
    """
    The error message displayed below the text field if the entered date is not in the \
    correct format.

    Defaults to `"Invalid format"`.
    """

    error_invalid_text: Optional[str] = None
    """
    The error message displayed below the text field if the date is earlier than \
    [`first_date`][(c).] or later than [`last_date`][(c).].

    Defaults to `"Out of range"`.
    """

    field_hint_text: Optional[str] = None
    """
    The hint text displayed in the text field.

    The default value is the date format string that depends on your locale.
    For example, `'mm/dd/yyyy'` for en_US.
    """

    field_label_text: Optional[str] = None
    """
    The label text displayed in the `TextField`.

    If `None`, defaults to the words representing the date format string.
    For example, `'Month, Day, Year'` for en_US.

    Defaults to `"Enter Date"`.
    """

    switch_to_calendar_icon: Optional[IconData] = None
    """
    The icon displayed in the corner of this picker's dialog when [`entry_mode`][(c).] \
    is [`DatePickerEntryMode.INPUT`][flet.].

    Clicking on this icon changes the [`entry_mode`][(c).] to
    [`DatePickerEntryMode.CALENDAR`][flet.].

    If `None`, defaults to `Icons.CALENDAR_TODAY`.
    """

    switch_to_input_icon: Optional[IconData] = None
    """
    The icon displayed in the corner of this picker's dialog when [`entry_mode`][(c).] \
    is [`DatePickerEntryMode.CALENDAR`][flet.].

    Clicking on icon changes the [`entry_mode`][(c).] to
    [`DatePickerEntryMode.INPUT`][flet.].

    If `None`, defaults to `Icons.EDIT_OUTLINED`.
    """

    barrier_color: Optional[ColorValue] = None
    """
    The color of the modal barrier that darkens everything below this picker's dialog.

    If `None`, the [`DialogTheme.barrier_color`][flet.] is used.
    If it is also `None`, then [`Colors.BLACK_54`][flet.] is used.
    """

    inset_padding: PaddingValue = field(
        default_factory=lambda: Padding.symmetric(horizontal=16.0, vertical=24.0)
    )
    """
    The amount of padding added to [`view_insets`][flet.PageMediaData.] of the \
    [`Page.media`][flet.] on the outside of this picker's dialog.

    This defines the minimum space between the screen's edges and the dialog.
    """

    on_change: Optional[ControlEventHandler["DatePicker"]] = None
    """
    Called when user clicks confirm button.
    [`value`][(c).] is updated with selected date.

    The [`data`][flet.Event.] property of the event handler argument
    contains the selected date.
    """

    on_entry_mode_change: Optional[EventHandler[DatePickerEntryModeChangeEvent]] = None
    """
    Called when the [`entry_mode`][(c).] is changed from the user interface.
    """
