from pathlib import Path from typing import Any, Callable, Optional, cast from typing_extensions import Self from ... import core from ...binding import BindableProperty, bind, bind_from, bind_to from ...element import Element from ...helpers import is_file class SourceElement(Element): source = BindableProperty( on_change=lambda sender, source: cast(Self, sender)._handle_source_change(source)) # pylint: disable=protected-access SOURCE_IS_MEDIA_FILE: bool = False def __init__(self, *, source: Any, **kwargs: Any) -> None: super().__init__(**kwargs) self.auto_route: Optional[str] = None self.source = source self._set_props(source) def bind_source_to(self, target_object: Any, target_name: str = 'source', forward: Optional[Callable[[Any], Any]] = None, *, strict: Optional[bool] = None, ) -> Self: """Bind the source of this element to the target object's target_name property. The binding works one way only, from this element to the target. The update happens immediately and whenever a value changes. :param target_object: The object to bind to. :param target_name: The name of the property to bind to. :param forward: A function to apply to the value before applying it to the target (default: identity). :param strict: Whether to check (and raise) if the target object has the specified property (default: None, performs a check if the object is not a dictionary, *added in version 3.0.0*). """ bind_to(self, 'source', target_object, target_name, forward, self_strict=False, other_strict=strict) return self def bind_source_from(self, target_object: Any, target_name: str = 'source', backward: Optional[Callable[[Any], Any]] = None, *, strict: Optional[bool] = None, ) -> Self: """Bind the source of this element from the target object's target_name property. The binding works one way only, from the target to this element. The update happens immediately and whenever a value changes. :param target_object: The object to bind from. :param target_name: The name of the property to bind from. :param backward: A function to apply to the value before applying it to this element (default: identity). :param strict: Whether to check (and raise) if the target object has the specified property (default: None, performs a check if the object is not a dictionary, *added in version 3.0.0*). """ bind_from(self, 'source', target_object, target_name, backward, self_strict=False, other_strict=strict) return self def bind_source(self, target_object: Any, target_name: str = 'source', *, forward: Optional[Callable[[Any], Any]] = None, backward: Optional[Callable[[Any], Any]] = None, strict: Optional[bool] = None, ) -> Self: """Bind the source of this element to the target object's target_name property. The binding works both ways, from this element to the target and from the target to this element. The update happens immediately and whenever a value changes. The backward binding takes precedence for the initial synchronization. :param target_object: The object to bind to. :param target_name: The name of the property to bind to. :param forward: A function to apply to the value before applying it to the target (default: identity). :param backward: A function to apply to the value before applying it to this element (default: identity). :param strict: Whether to check (and raise) if the target object has the specified property (default: None, performs a check if the object is not a dictionary, *added in version 3.0.0*). """ bind(self, 'source', target_object, target_name, forward=forward, backward=backward, self_strict=False, other_strict=strict) return self def set_source(self, source: Any) -> None: """Set the source of this element. :param source: The new source. """ self.source = source def _handle_source_change(self, source: Any) -> None: """Called when the source of this element changes. :param source: The new source. """ self._set_props(source) def _set_props(self, source: Any) -> None: if is_file(source): if self.auto_route: core.app.remove_route(self.auto_route) if self.SOURCE_IS_MEDIA_FILE: source = core.app.add_media_file(local_file=source) else: source = core.app.add_static_file(local_file=source) self.auto_route = source if isinstance(source, Path) and not source.exists(): raise FileNotFoundError(f'File not found: {source}') self._props['src'] = source def _handle_delete(self) -> None: if self.auto_route: core.app.remove_route(self.auto_route) return super()._handle_delete()