gaphas.port - Gaphas

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# Source code for gaphas.port

    """Basic connectors such as Ports and Handles."""

    from __future__ import annotations

    from typing import TYPE_CHECKING

    from gaphas.constraint import Constraint, LineConstraint, PositionConstraint
    from gaphas.geometry import distance_line_point, distance_point_point
    from gaphas.handle import Handle
    from gaphas.position import MatrixProjection, Position
    from gaphas.solver import MultiConstraint
    from gaphas.types import Pos, SupportsFloatPos

    if TYPE_CHECKING:
        from gaphas.item import Item

    class Port:
        """Port connectable part of an item.

        The Item's handle connects to a port.
        """

        def __init__(self) -> None:
            super().__init__()

            self._connectable = True

        def _set_connectable(self, connectable: bool) -> None:
            self._connectable = connectable

        connectable = property(lambda s: s._connectable, _set_connectable)

        def glue(self, pos: SupportsFloatPos) -> tuple[Pos, float]:
            """Get glue point on the port and distance to the port."""
            raise NotImplementedError("Glue method not implemented")

        def constraint(self, item: Item, handle: Handle, glue_item: Item) -> Constraint:
            """Create connection constraint between item's handle and glue item."""
            raise NotImplementedError("Constraint method not implemented")

    class LinePort(Port):
        """Port defined as a line between two handles."""

        def __init__(self, start: Position, end: Position) -> None:
            super().__init__()

            self.start = start
            self.end = end

        def glue(self, pos: SupportsFloatPos) -> tuple[Pos, float]:
            """Get glue point on the port and distance to the port.

            >>> p1, p2 = (0.0, 0.0), (100.0, 100.0)
            >>> port = LinePort(p1, p2)
            >>> port.glue((50, 50))
            ((50.0, 50.0), 0.0)
            >>> port.glue((0, 10))
            ((5.0, 5.0), 7.0710678118654755)
            """
            d, pl = distance_line_point(
                self.start.tuple(), self.end.tuple(), (float(pos[0]), float(pos[1]))
            )
            return pl, d

        def constraint(self, item: Item, handle: Handle, glue_item: Item) -> Constraint:
            """Create connection line constraint between item's handle and the
            port."""
            start = MatrixProjection(self.start, glue_item.matrix_i2c)
            end = MatrixProjection(self.end, glue_item.matrix_i2c)
            point = MatrixProjection(handle.pos, item.matrix_i2c)
            line = LineConstraint((start.pos, end.pos), point.pos)
            return MultiConstraint(start, end, point, line)

    class PointPort(Port):
        """Port defined as a point."""

        def __init__(self, point: Position) -> None:
            super().__init__()
            self.point = point

        def glue(self, pos: SupportsFloatPos) -> tuple[Pos, float]:
            """Get glue point on the port and distance to the port.

            >>> h = Handle((10, 10))
            >>> port = PointPort(h.pos)
            >>> port.glue((10, 0))
            (<Position object on (10, 10)>, 10.0)
            """
            point: tuple[float, float] = self.point.pos  # type: ignore[assignment]
            d = distance_point_point(point, (float(pos[0]), float(pos[1])))
            return point, d

        def constraint(
            self, item: Item, handle: Handle, glue_item: Item
        ) -> MultiConstraint:
            """Return connection position constraint between item's handle and the
            port."""
            origin = MatrixProjection(self.point, glue_item.matrix_i2c)
            point = MatrixProjection(handle.pos, item.matrix_i2c)
            c = PositionConstraint(origin.pos, point.pos)
            return MultiConstraint(origin, point, c)