''' Load Fritzing part files as Schemdraw elements See https://github.com/fritzing/fritzing-app/wiki/2.1-Part-file-format Only extracts the breadboard view (schematic, PCB, and icon are not used) ''' from __future__ import annotations from typing import Optional import re import warnings import zipfile from io import BytesIO from collections import namedtuple from xml.etree import ElementTree as ET from ..util import Point from ..backends import matrix from ..elements import ElementImage from .pictorial import parse_size_to_units FritzingInfo = namedtuple('FritzingInfo', 'author version title url label date description') def find_transforms(element, tree): '''' Find all 'transform' tags in tree leading up to element ''' parents = {c: p for p in tree.iter() for c in p} xforms = [] def _find(elm): if (xf := elm.get('transform')): xforms.append(xf) p = parents.get(elm) if p is not None: _find(p) _find(element) return xforms def extract(elm: ET.Element, tag: str) -> Optional[str]: ''' Extract the tag's text from the element, returning None if tag doesn't exist ''' item = elm.find(tag) return item.text if item is not None else None def fritz_parts(fname: str) -> list[str | None]: ''' List titles of all Fritzing parts in the file ''' zip = zipfile.ZipFile(fname) parts = [f.filename for f in zip.infolist() if f.filename.endswith('.fzp')] names = [] for part in parts: module = ET.fromstring(zip.read(part)) title = module.find('title') if title is not None: names.append(title.text) return names class FritzingPart(ElementImage): ''' Load a Fritzing Part File as a Schemdraw Element Anchors will be extracted from the Part definition file. Note some anchors are not valid Python identifiers and therefore must be accessed through the Element.absanchors dictionary rather than an attribute of the element instance. Args: fname: Filename of fritzing .fzpz archive partname: Name of part within the file. Use `listparts` to show all names. If not provided, first part is drawn. partidx: Index of part within the file. If not provided, first part is drawn. Overrides `partname`. scale: Scale factor ''' def __init__(self, fname: str, partname: Optional[str] = None, partidx: Optional[int] = None, scale: float = 1.0): self.fname = fname self.zip = zipfile.ZipFile(self.fname) parts = [f.filename for f in self.zip.infolist() if f.filename.endswith('.fzp')] if partidx is not None: part = parts[partidx] elif partname is not None: part = parts[fritz_parts(fname).index(partname)] else: part = parts[0] self.module = ET.fromstring(self.zip.read(part)) self.info = FritzingInfo( author=extract(self.module, 'author'), version=extract(self.module, 'version'), title=extract(self.module, 'title'), url=extract(self.module, 'url'), label=extract(self.module, 'label'), date=extract(self.module, 'date'), description=extract(self.module, 'description'), ) views = self.module.find('views') if views is None: raise ValueError('Part has no views') breadboard = views.find('breadboardView') if breadboard is None: raise ValueError('Part has no breadboardView') layers = breadboard.find('layers') if layers is None: raise ValueError('Part breadboardView has no layers') svgfile = layers.get('image', '') image = self.zip.read('svg.' + svgfile.replace('/', '.')) imagebuf = BytesIO(image) self.imagexml = ET.fromstring(image) width = self.imagexml.get('width', '0') height = self.imagexml.get('height', '0') self.width_units = parse_size_to_units(width) * scale self.height_units = parse_size_to_units(height) * scale if self.width_units == 0 or self.height_units == 0: warnings.warn('Part has 0 width or height') viewbox = self.imagexml.get('viewBox') if viewbox: _, _, vieww, viewh = viewbox.split() self.vieww = float(vieww) self.viewh = float(viewh) self._scale = self.width_units / self.vieww else: # Some examples don't have a viewBox, assume same as width/height try: width_f = float(width) except ValueError: width_f = float(width[:-2]) self._scale = self.width_units / width_f super().__init__(image=imagebuf, imgfmt='svg', width=self.width_units, height=self.height_units) self._findanchors() def _anchor_position(self, name: str, anchorelm: ET.Element) -> tuple[Optional[float], Optional[float]]: ''' Extract position of the anchor element from its SVG tag ''' matrices: list[matrix.Matrix3x3] = [] anchorx: Optional[float] = None anchory: Optional[float] = None # Anchor is SVG tag, pick out the exact point if anchorelm.tag.endswith('circle') or anchorelm.tag.endswith('ellipse'): anchorx = float(anchorelm.get('cx', '0')) anchory = float(anchorelm.get('cy', '0')) elif anchorelm.tag.endswith('rect'): rectwidth = float(anchorelm.get('width', '0')) rectheight = float(anchorelm.get('height', '0')) anchorx = float(anchorelm.get('x', '0')) + rectwidth/2 anchory = float(anchorelm.get('y', '0')) + rectheight/2 elif anchorelm.tag.endswith('polygon'): pointlist = anchorelm.get('points', '') pointstrs = re.split(',| ', pointlist) points = [float(p) for p in pointstrs if p] xpoints = points[::2] ypoints = points[1::2] anchorx = (max(xpoints) + min(xpoints)) / 2 anchory = (max(ypoints) + min(ypoints)) / 2 elif anchorelm.tag.endswith('path'): path = anchorelm.get('d', '') path = path.replace('-', ' -') # Some negative numbers don't have space before pointstrs = re.split(',| |M|L|H|V|Q|C|A|Z|m|l|h|v|q|c|a|z', path) # First item in list is 'M' directive, or similar # Let anchor just be the first point in the path. # Could be that center of path was intended, but that will get weird # with Bezier control points, etc. # NOTE: relative (lowercase m) moves won't work correctly pointstrs = [p for p in pointstrs if p] anchorx = float(pointstrs[0]) anchory = float(pointstrs[1]) elif anchorelm.tag.endswith('g'): # Set anchor based on first element within the group if len(anchorelm) > 0: return self._anchor_position(name, anchorelm[0]) else: warnings.warn(f'Connector {name} is empty') return None, None else: warnings.warn(f'Connector {name} unimplemented connector tag: {anchorelm.tag}') return None, None # Pick out SVG transforms leading up to the anchor element xforms = find_transforms(anchorelm, self.imagexml) for xf in xforms: for xfmode, value in re.findall(r'(.*?)\((.*?)\)', xf): xfmode = xfmode.strip() valuestrs = re.split(',| ', value) values = [float(v) for v in valuestrs if v] if xfmode == 'translate': m = matrix.matrix_translate(*values) elif xfmode == 'rotate': m = matrix.matrix_rotate(*values) elif xfmode == 'scale': m = matrix.matrix_scale(*values) elif xfmode == 'skewX': m = matrix.matrix_skewx(values[0]) elif xfmode == 'skewY': m = matrix.matrix_skewy(values[0]) elif xfmode == 'matrix': m = matrix.matrix(*values) else: raise NotImplementedError(f'Transform {xfmode} not implemented') matrices.append(m) # Apply the transformation matrices and scale to drawing units anchorx, anchory = matrix.transform_all(Point((anchorx, anchory)), matrices) anchorx = anchorx * self._scale anchory = self.height_units - anchory * self._scale return anchorx, anchory def _findanchors(self): ''' Find anchor positions ''' for connector in self.module.find('connectors'): name = connector.get('name') breadboard = connector.find('views').find('breadboardView') svgid = breadboard.find('p').get('svgId') anchorelm = self.imagexml.findall(f".//*[@id='{svgid}']") if len(anchorelm) == 0: anchorelm = self.imagexml.findall(f".//*[@id='{svgid}pin']") if len(anchorelm) == 0: return anchorelm = anchorelm[0] anchorx, anchory = self._anchor_position(name, anchorelm) if anchorx is not None and anchory is not None: self.anchors[name] = Point((anchorx, anchory))