#!/usr/bin/env python # -*- coding: utf-8 -*- """ This file contains all the classes needed to perform layout of text-elements. This includes; ChunkOfText, LineOfText, Paragraph and Heading """ import typing from decimal import Decimal from borb.pdf.canvas.color.color import Color from borb.pdf.canvas.color.color import HexColor from borb.pdf.canvas.font.font import Font from borb.pdf.canvas.geometry.rectangle import Rectangle from borb.pdf.canvas.layout.hyphenation.hyphenation import Hyphenation from borb.pdf.canvas.layout.layout_element import Alignment from borb.pdf.canvas.layout.text.line_of_text import LineOfText from borb.pdf.canvas.layout.text.text_to_line_splitter import TextToLineSplitter from borb.pdf.page.page import Page class Paragraph(LineOfText): """ A paragraph (from the Ancient Greek παράγραφος, parágraphos, "to write beside") is a self-contained unit of discourse in writing dealing with a particular point or idea. A paragraph consists of one or more sentences. Though not required by the syntax of any language, paragraphs are usually an expected part of formal writing, used to organize longer prose. """ # # CONSTRUCTOR # def __init__( self, text: str, background_color: typing.Optional[Color] = None, border_bottom: bool = False, border_color: Color = HexColor("000000"), border_left: bool = False, border_radius_bottom_left: Decimal = Decimal(0), border_radius_bottom_right: Decimal = Decimal(0), border_radius_top_left: Decimal = Decimal(0), border_radius_top_right: Decimal = Decimal(0), border_right: bool = False, border_top: bool = False, border_width: Decimal = Decimal(1), fixed_leading: typing.Optional[Decimal] = None, font: typing.Union[Font, str] = "Helvetica", font_color: Color = HexColor("000000"), font_size: Decimal = Decimal(12), horizontal_alignment: Alignment = Alignment.LEFT, hyphenation: typing.Optional[Hyphenation] = None, margin_bottom: typing.Optional[Decimal] = None, margin_left: typing.Optional[Decimal] = None, margin_right: typing.Optional[Decimal] = None, margin_top: typing.Optional[Decimal] = None, multiplied_leading: typing.Optional[Decimal] = None, padding_bottom: Decimal = Decimal(0), padding_left: Decimal = Decimal(0), padding_right: Decimal = Decimal(0), padding_top: Decimal = Decimal(0), respect_newlines_in_text: bool = False, respect_spaces_in_text: bool = False, text_alignment: Alignment = Alignment.LEFT, vertical_alignment: Alignment = Alignment.TOP, ): super().__init__( text=text, font=font, font_size=font_size, vertical_alignment=vertical_alignment, horizontal_alignment=horizontal_alignment, font_color=font_color, border_top=border_top, border_right=border_right, border_bottom=border_bottom, border_left=border_left, border_radius_top_left=border_radius_top_left, border_radius_top_right=border_radius_top_right, border_radius_bottom_right=border_radius_bottom_right, border_radius_bottom_left=border_radius_bottom_left, border_color=border_color, border_width=border_width, padding_top=padding_top, padding_right=padding_right, padding_bottom=padding_bottom, padding_left=padding_left, margin_top=margin_top, margin_right=margin_right, margin_bottom=margin_bottom, margin_left=margin_left, multiplied_leading=multiplied_leading, fixed_leading=fixed_leading, background_color=background_color, ) self._respect_newlines_in_text = respect_newlines_in_text self._respect_spaces_in_text = respect_spaces_in_text self._hyphenation = hyphenation # alignment assert text_alignment in [ Alignment.LEFT, Alignment.CENTERED, Alignment.RIGHT, Alignment.JUSTIFIED, ] self._text_alignment = text_alignment # layout self._previous_lines_of_text: typing.Optional[typing.List[LineOfText]] = None # # PRIVATE # def __hash__(self) -> int: attr: typing.List[typing.Any] = [ self._text, self._font, self._font_size, self._vertical_alignment, self._horizontal_alignment, self._font_color, self._border_top, self._border_right, self._border_bottom, self._border_left, self._border_radius_top_left, self._border_radius_top_right, self._border_radius_bottom_right, self._border_radius_bottom_left, self._border_color, self._border_width, self._padding_top, self._padding_right, self._padding_bottom, self._padding_left, self._margin_top, self._margin_right, self._margin_bottom, self._margin_left, self._multiplied_leading, self._fixed_leading, self._background_color, ] attr_hash_for_layout: int = 1927868237 for a in attr: h: int = hash(a) attr_hash_for_layout ^= (h ^ (h << 16) ^ 89869747) * 3644798167 return attr_hash_for_layout * 69069 + 907133923 def _get_content_box(self, available_space: Rectangle) -> Rectangle: # This code gets screwed over by cached_by_hash # TODO: investigate # if the hash has changed, it implies some attributes that are relevant to layout have changed # we need to recalculate the content_box # otherwise we can just skip this and return the previously calculated content_box assert self._font_size is not None lines_of_text = [ LineOfText( x, font=self._font, font_size=self._font_size, font_color=self._font_color, horizontal_alignment=self._text_alignment, multiplied_leading=self._multiplied_leading, text_alignment=self._text_alignment, fixed_leading=self._fixed_leading, ) for x in self._split_text(available_space) ] # When using justification, # it is customary to treat the last line of a paragraph separately by simply left or right aligning it, # depending on the language direction. if self._text_alignment == Alignment.JUSTIFIED: lines_of_text[-1]._text_alignment = Alignment.LEFT # determine line height assert self._font_size is not None line_height: Decimal = self._font_size if self._multiplied_leading is not None: line_height *= self._multiplied_leading if self._fixed_leading is not None: line_height += self._fixed_leading # determine content box height h: Decimal = line_height * len(lines_of_text) # determine content box width w: Decimal = Decimal(0) for i, l in enumerate(lines_of_text): lbox: Rectangle = l._get_content_box( Rectangle( available_space.get_x(), available_space.get_y() + available_space.get_height() - (i + 1) * line_height, available_space.get_width(), line_height, ) ) w = max(w, lbox.get_width()) # store self._previous_lines_of_text self._previous_lines_of_text = lines_of_text # determine content box return Rectangle( available_space.get_x(), available_space.get_y() + available_space.get_height() - h, w, h, ) def _paint_content_box(self, page: Page, available_space: Rectangle) -> None: # ensure everything is initialized self._get_content_box(available_space) # determine line height assert self._font_size is not None line_height: Decimal = self._font_size if self._multiplied_leading is not None: line_height *= self._multiplied_leading if self._fixed_leading is not None: line_height += self._fixed_leading # if the Paragraph needs to be tagged, insert (STARTING) tagging operators # TODO: determine next MCID if self._needs_to_be_tagged(page): next_mcid: int = 0 page.append_to_content_stream("\n/Standard <>\nBDC\n" % next_mcid) # check whether it can be painted assert self._previous_lines_of_text is not None if round(available_space.get_height(), 2) < round( line_height * len(self._previous_lines_of_text), 2 ): self._split_text(available_space) assert False # call paint on all LineOfText objects for i, l in enumerate(self._previous_lines_of_text): l.paint( page, Rectangle( available_space.get_x(), available_space.get_y() + available_space.get_height() - (i + 1) * line_height, available_space.get_width(), line_height, ), ) # if the Paragraph needs to be tagged, insert (CLOSING) tagging operators if self._needs_to_be_tagged(page): page.append_to_content_stream("\nEMC\n") def _split_text(self, bounding_box: Rectangle) -> typing.List[str]: return TextToLineSplitter.text_to_lines( bounding_box=bounding_box, font=self.get_font(), font_size=self.get_font_size(), text=self.get_text(), hyphenation=self._hyphenation, respect_newlines=self._respect_newlines_in_text, respect_spaces=self._respect_spaces_in_text, ) # # PUBLIC #