#!/usr/bin/env python
# -*- coding: utf-8 -*-

"""
Begin a new subpath by moving the current point to
coordinates (x, y), omitting any connecting line segment. If
the previous path construction operator in the current path
was also m, the new m overrides it; no vestige of the
previous m operation remains in the path.
"""
import typing
from decimal import Decimal

from borb.io.read.types import AnyPDFType
from borb.pdf.canvas.geometry.line_segment import LineSegment
from borb.pdf.canvas.operator.canvas_operator import CanvasOperator


class BeginSubpath(CanvasOperator):
    """
    Begin a new subpath by moving the current point to
    coordinates (x, y), omitting any connecting line segment. If
    the previous path construction operator in the current path
    was also m, the new m overrides it; no vestige of the
    previous m operation remains in the path.
    """

    #
    # CONSTRUCTOR
    #

    def __init__(self):
        super().__init__("m", 2)

    #
    # PRIVATE
    #

    #
    # PUBLIC
    #

    def invoke(
        self,
        canvas_stream_processor: "CanvasStreamProcessor",  # type: ignore [name-defined]
        operands: typing.List[AnyPDFType] = [],
        event_listeners: typing.List["EventListener"] = [],  # type: ignore [name-defined]
    ) -> None:
        """
        Invoke the m operator
        :param canvas_stream_processor:     the CanvasStreamProcessor
        :param operands:                    the operands for this CanvasOperator
        :param event_listeners:             the typing.List of EventListener(s) that may be notified
        :return:                            None
        """
        assert isinstance(
            operands[0], Decimal
        ), "operand 0 of m operator must be of type Decimal"
        assert isinstance(
            operands[1], Decimal
        ), "operand 1 of m operator must be of type Decimal"

        # get graphic state
        canvas = canvas_stream_processor.get_canvas()
        gs = canvas.graphics_state

        # start empty subpath
        gs.path.append(LineSegment(operands[0], operands[1], operands[0], operands[1]))