Add initial support for buttons and components

1 files changed, 288 insertions, 0 deletions

diff --git a/discord/ui/button.py b/discord/ui/button.py
new file mode 100644
index 00000000..afc69f7a
--- /dev/null
+++ b/discord/ui/button.py
@@ -0,0 +1,288 @@
+"""
+The MIT License (MIT)
+
+Copyright (c) 2015-present Rapptz
+
+Permission is hereby granted, free of charge, to any person obtaining a
+copy of this software and associated documentation files (the "Software"),
+to deal in the Software without restriction, including without limitation
+the rights to use, copy, modify, merge, publish, distribute, sublicense,
+and/or sell copies of the Software, and to permit persons to whom the
+Software is furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+DEALINGS IN THE SOFTWARE.
+"""
+
+from __future__ import annotations
+
+from typing import Callable, Optional, TYPE_CHECKING, Tuple, Type, TypeVar, Union
+import inspect
+import re
+import os
+
+
+from .item import Item, ItemCallbackType
+from ..enums import ButtonStyle, ComponentType
+from ..partial_emoji import PartialEmoji
+from ..components import Button as ButtonComponent
+
+__all__ = (
+    'Button',
+    'button',
+)
+
+if TYPE_CHECKING:
+    from ..components import Component
+
+_custom_emoji = re.compile(r'<?(?P<animated>a)?:?(?P<name>[A-Za-z0-9\_]+):(?P<id>[0-9]{13,20})>?')
+
+
+def _to_partial_emoji(obj: Union[str, PartialEmoji], *, _custom_emoji=_custom_emoji) -> PartialEmoji:
+    if isinstance(obj, PartialEmoji):
+        return obj
+
+    obj = str(obj)
+    match = _custom_emoji.match(obj)
+    if match is not None:
+        groups = match.groupdict()
+        animated = bool(groups['animated'])
+        emoji_id = int(groups['id'])
+        name = groups['name']
+        return PartialEmoji(name=name, animated=animated, id=emoji_id)
+
+    return PartialEmoji(name=obj, id=None, animated=False)
+
+
+B = TypeVar('B', bound='Button')
+
+
+class Button(Item):
+    """Represents a UI button.
+
+    .. versionadded:: 2.0
+
+    Parameters
+    ------------
+    style: :class:`discord.ButtonStyle`
+        The style of the button.
+    custom_id: Optional[:class:`str`]
+        The ID of the button that gets received during an interaction.
+        If this button is for a URL, it does not have a custom ID.
+    url: Optional[:class:`str`]
+        The URL this button sends you to.
+    disabled: :class:`bool`
+        Whether the button is disabled or not.
+    label: :class:`str`
+        The label of the button.
+    emoji: Optional[:class:`PartialEmoji`]
+        The emoji of the button, if available.
+    """
+
+    __slots__: Tuple[str, ...] = Item.__slots__ + ('_underlying',)
+
+    __item_repr_attributes__: Tuple[str, ...] = (
+        'style',
+        'url',
+        'disabled',
+        'label',
+        'emoji',
+        'group_id',
+    )
+
+    def __init__(
+        self,
+        *,
+        style: ButtonStyle,
+        label: str,
+        disabled: bool = False,
+        custom_id: Optional[str] = None,
+        url: Optional[str] = None,
+        emoji: Optional[Union[str, PartialEmoji]] = None,
+        group: Optional[int] = None,
+    ):
+        super().__init__()
+        if custom_id is not None and url is not None:
+            raise TypeError('cannot mix both url and custom_id with Button')
+
+        if url is None and custom_id is None:
+            custom_id = os.urandom(16).hex()
+
+        self._underlying = ButtonComponent._raw_construct(
+            type=ComponentType.button,
+            custom_id=custom_id,
+            url=url,
+            disabled=disabled,
+            label=label,
+            style=style,
+            emoji=None if emoji is None else _to_partial_emoji(emoji),
+        )
+        self.group_id = group
+
+    @property
+    def style(self) -> ButtonStyle:
+        """:class:`discord.ButtonStyle`: The style of the button."""
+        return self._underlying.style
+
+    @style.setter
+    def style(self, value: ButtonStyle):
+        self._underlying.style = value
+
+    @property
+    def custom_id(self) -> Optional[str]:
+        """Optional[:class:`str`]: The ID of the button that gets received during an interaction.
+
+        If this button is for a URL, it does not have a custom ID.
+        """
+        return self._underlying.custom_id
+
+    @custom_id.setter
+    def custom_id(self, value: Optional[str]):
+        if value is not None and not isinstance(value, str):
+            raise TypeError('custom_id must be None or str')
+
+        self._underlying.custom_id = value
+
+    @property
+    def url(self) -> Optional[str]:
+        """Optional[:class:`str`]: The URL this button sends you to."""
+        return self._underlying.url
+
+    @url.setter
+    def url(self, value: Optional[str]):
+        if value is not None and not isinstance(value, str):
+            raise TypeError('url must be None or str')
+        self._underlying.url = value
+
+    @property
+    def disabled(self) -> bool:
+        """:class:`bool`: Whether the button is disabled or not."""
+        return self._underlying.disabled
+
+    @disabled.setter
+    def disabled(self, value: bool):
+        self._underlying.disabled = bool(value)
+
+    @property
+    def label(self) -> str:
+        """:class:`str`: The label of the button."""
+        return self._underlying.label
+
+    @label.setter
+    def label(self, value: str):
+        self._underlying.label = str(value)
+
+    @property
+    def emoji(self) -> Optional[PartialEmoji]:
+        """Optional[:class:`PartialEmoji`]: The emoji of the button, if available."""
+        return self._underlying.emoji
+
+    @emoji.setter
+    def emoji(self, value: Optional[Union[str, PartialEmoji]]):  # type: ignore
+        if value is not None:
+            self._underlying.emoji = _to_partial_emoji(value)
+        else:
+            self._underlying.emoji = None
+
+    def copy(self: B) -> B:
+        button = self.__class__(
+            style=self.style,
+            label=self.label,
+            disabled=self.disabled,
+            custom_id=self.custom_id,
+            url=self.url,
+            emoji=self.emoji,
+            group=self.group_id,
+        )
+        button.callback = self.callback
+        return button
+
+    @classmethod
+    def from_component(cls: Type[B], button: ButtonComponent) -> B:
+        return cls(
+            style=button.style,
+            label=button.label,
+            disabled=button.disabled,
+            custom_id=button.custom_id,
+            url=button.url,
+            emoji=button.emoji,
+            group=None,
+        )
+
+    @property
+    def type(self) -> ComponentType:
+        return self._underlying.type
+
+    def to_component_dict(self):
+        return self._underlying.to_dict()
+
+    def is_dispatchable(self) -> bool:
+        return True
+
+    def refresh_state(self, button: ButtonComponent) -> None:
+        self._underlying = button
+
+
+def button(
+    label: str,
+    *,
+    custom_id: Optional[str] = None,
+    disabled: bool = False,
+    style: ButtonStyle = ButtonStyle.grey,
+    emoji: Optional[Union[str, PartialEmoji]] = None,
+    group: Optional[int] = None,
+) -> Callable[[ItemCallbackType], Button]:
+    """A decorator that attaches a button to a component.
+
+    The function being decorated should have three parameters, ``self`` representing
+    the :class:`discord.ui.View`, the :class:`discord.ui.Button` being pressed and
+    the :class:`discord.Interaction` you receive.
+
+    .. note::
+
+        Buttons with a URL cannot be created with this function.
+        Consider creating a :class:`Button` manually instead.
+        This is because buttons with a URL do not have a callback
+        associated with them since Discord does not do any processing
+        with it.
+
+    Parameters
+    ------------
+    label: :class:`str`
+        The label of the button.
+    custom_id: Optional[:class:`str`]
+        The ID of the button that gets received during an interaction.
+        It is recommended not to set this parameter to prevent conflicts.
+    style: :class:`ButtonStyle`
+        The style of the button. Defaults to :attr:`ButtonStyle.grey`.
+    disabled: :class:`bool`
+        Whether the button is disabled or not. Defaults to ``False``.
+    emoji: Optional[Union[:class:`str`, :class:`PartialEmoji`]]
+        The emoji of the button. This can be in string form or a :class:`PartialEmoji`.
+    group: Optional[:class:`int`]
+        The relative group this button belongs to. A Discord component can only have 5
+        groups. By default, items are arranged automatically into those 5 groups. If you'd
+        like to control the relative positioning of the group then passing an index is advised.
+        For example, group=1 will show up before group=2. Defaults to ``None``, which is automatic
+        ordering.
+    """
+
+    def decorator(func: ItemCallbackType) -> Button:
+        nonlocal custom_id
+        if not inspect.iscoroutinefunction(func):
+            raise TypeError('button function must be a coroutine function')
+
+        custom_id = custom_id or os.urandom(32).hex()
+        button = Button(style=style, custom_id=custom_id, url=None, disabled=disabled, label=label, emoji=emoji, group=group)
+        button.callback = func
+        return button
+
+    return decorator