Source code for pystrich.code39

"""Code-39 barcode encoder

All needed by the user is done via the Code39Encoder class:

>>> encoder = Code39Encoder("MIL-STD-1189")
>>> encoder.save("test.png")

You may use this under a BSD License.
"""

from __future__ import annotations

import logging

from pystrich.bar_encoder import Bar1DEncoder
from pystrich.types import BarcodeRenderOptions

from .renderer import Code39Renderer
from .textencoder import TextEncoder

log = logging.getLogger("code39")




class Code39Encoder(Bar1DEncoder):
    """Encode a string as a Code 39 1D barcode.

    By default only the standard Code 39 character set is accepted
    (``0-9``, ``A-Z``, space, and ``-.$/+%``). Pass ``full_ascii=True`` to
    use the Full ASCII extension, which encodes any 7-bit character via
    paired symbols.

    Typical use::

        encoder = Code39Encoder("ABC-123")
        encoder.save("barcode.png")

    :ivar text: The original input text.
    :ivar encoded_text: List of code values produced by the text encoder.
    :ivar bars: The bar/space pattern as a string of ``"1"`` and ``"0"``.
    :ivar options: Render-time options dict (empty if none were supplied).
    :ivar width: Pixel width of the most recently rendered image.
    :ivar height: Pixel height of the most recently rendered image.
    """

    options: BarcodeRenderOptions
    text: str
    encoded_text: list[int]
    bars: str

    def __init__(
        self,
        text: str,
        full_ascii: bool = False,
        options: BarcodeRenderOptions | None = None,
    ) -> None:
        """Encode ``text`` as Code 39.

        :param text: The data to encode.
        :param full_ascii: If ``True``, use the Full ASCII extension so any
            7-bit character can be represented (each non-standard character
            becomes a pair of symbols).
        :param options: Optional dict tweaking the rendered output. Supported
            keys:

            * ``ttf_font`` -- absolute path to a TrueType font for the label.
              Defaults to a bundled bitmap font.
            * ``ttf_fontsize`` -- font size in points.
            * ``show_label`` -- whether to render the human-readable label
              underneath the bars (defaults to ``True``).
            * ``height`` -- total image height in pixels (defaults to ``120``).
            * ``label_border`` -- pixels of space between barcode and label.
            * ``bottom_border`` -- pixels of space between label and the
              bottom edge.
        """
        super().__init__(options)
        self.text = text
        encoder = TextEncoder()

        self.encoded_text = encoder.encode(self.text, full_ascii)
        log.debug("Encoded text is %s", self.encoded_text)

        self.bars = encoder.get_bars(self.encoded_text)
        log.debug("Bars: %s", self.bars)



    def init_renderer(self) -> Code39Renderer:
        """Construct a :class:`Code39Renderer` for the encoded bars.

        :rtype: :class:`Code39Renderer`
        """
        return Code39Renderer(self.bars, self.text, self.options)