path: root/gerbonara/cam.py

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

# copyright 2014 Hamilton Kibbe <ham@hamiltonkib.be>
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at

#     http://www.apache.org/licenses/LICENSE-2.0

# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

import math
from dataclasses import dataclass
from copy import deepcopy
from enum import Enum
import string

from .utils import LengthUnit, MM, Inch, Tag
from . import graphic_primitives as gp
from . import graphic_objects as go

@dataclass
class FileSettings:
    '''
    .. note::
        Format and zero suppression are configurable. Note that the Excellon
        and Gerber formats use opposite terminology with respect to leading
        and trailing zeros. The Gerber format specifies which zeros are
        suppressed, while the Excellon format specifies which zeros are
        included. This function uses the Gerber-file convention, so an
        Excellon file in LZ (leading zeros) mode would use
        `zeros='trailing'`
    '''
    notation : str = 'absolute'
    unit : LengthUnit = MM
    angle_unit : str = 'degree'
    zeros : bool = None
    number_format : tuple = (2, 5)

    # input validation
    def __setattr__(self, name, value):
        if name == 'unit' and value not in [MM, Inch]:
            raise ValueError(f'Unit must be either Inch or MM, not {value}')
        elif name == 'notation' and value not in ['absolute', 'incremental']:
            raise ValueError(f'Notation must be either "absolute" or "incremental", not {value}')
        elif name == 'angle_unit' and value not in ('degree', 'radian'):
            raise ValueError(f'Angle unit may be "degree" or "radian", not {value}')
        elif name == 'zeros' and value not in [None, 'leading', 'trailing']:
            raise ValueError(f'zeros must be either "leading" or "trailing" or None, not {value}')
        elif name == 'number_format':
            if len(value) != 2:
                raise ValueError(f'Number format must be a (integer, fractional) tuple of integers, not {value}')

            if value != (None, None) and (value[0] > 6 or value[1] > 7):
                raise ValueError(f'Requested precision of {value} is too high. Only up to 6.7 digits are supported by spec.')


        super().__setattr__(name, value)

    def to_radian(self, value):
        value = float(value)
        return math.radians(value) if self.angle_unit == 'degree' else value

    def parse_ipc_length(self, value, default=None):
        if value is None or not str(value).strip():
            return default

        if isinstance(value, str) and value[0].isalpha():
            value = value[1:]

        value = int(value)
        value *= 0.0001 if self.is_inch else 0.001
        return value

    def format_ipc_number(self, value, digits, key='', sign=False):
        if value is None:
            return ' ' * (digits + int(bool(sign)) + len(key))

        if isinstance(value, Enum):
            value = value.value
        num = format(round(value), f'{"+" if sign else ""}0{digits+int(bool(sign))}d')

        if len(num) > digits + int(bool(sign)):
            raise ValueError('Error: Number {num} to wide for IPC-356 field of width {digits}')

        return key + num

    def format_ipc_length(self, value, digits, key='', unit=None, sign=False):
        if value is not None:
            value = self.unit(value, unit)
            value /= 0.0001 if self.is_inch else  0.001

        return self.format_ipc_number(value, digits, key, sign=sign)

    @property
    def is_metric(self):
        return self.unit == MM

    @property
    def is_inch(self):
        return self.unit == Inch

    def copy(self):
        return deepcopy(self)

    def __str__(self):
        return f'<File settings: unit={self.unit}/{self.angle_unit} notation={self.notation} zeros={self.zeros} number_format={self.number_format}>'

    @property
    def incremental(self):
        return self.notation == 'incremental'

    @property
    def absolute(self):
        return not self.incremental # default to absolute

    def parse_gerber_value(self, value):
        if not value:
            return None

        # Handle excellon edge case with explicit decimal. "That was easy!"
        if '.' in value:
            return float(value)

        # TARGET3001! exports zeros as "00" even when it uses an explicit decimal point everywhere else.
        if int(value) == 0:
            return 0

        # Format precision
        integer_digits, decimal_digits = self.number_format
        if integer_digits is None or decimal_digits is None:
            raise SyntaxError('No number format set and value does not contain a decimal point. If this is an Allegro '
                    'Excellon drill file make sure either nc_param.txt or ncdrill.log ends up in the same folder as '
                    'it, because Allegro does not include this critical information in their Excellon output. If you '
                    'call this through ExcellonFile.from_string, you must manually supply from_string with a '
                    'FileSettings object from excellon.parse_allegro_ncparam.')

        # Remove extraneous information
        sign = '-' if value[0] == '-' else ''
        value = value.lstrip('+-')

        if self.zeros == 'leading':
            value = '0'*decimal_digits + value # pad with zeros to ensure we have enough decimals
            out = float(sign + value[:-decimal_digits] + '.' + value[-decimal_digits:])

        else: # no or trailing zero suppression
            value = value + '0'*integer_digits
            out = float(sign + value[:integer_digits] + '.' + value[integer_digits:])
        return out

    def write_gerber_value(self, value, unit=None):
        """ Convert a floating point number to a Gerber/Excellon-formatted string.  """

        if unit is not None:
            value = self.unit(value, unit)
        
        integer_digits, decimal_digits = self.number_format
        if integer_digits is None:
            integer_digits = 3
        if decimal_digits is None:
            decimal_digits = 3

        # negative sign affects padding, so deal with it at the end...
        sign = '-' if value < 0 else ''

        # FIXME never use exponential notation here
        num = format(abs(value), f'0{integer_digits+decimal_digits+1}.{decimal_digits}f').replace('.', '')

        # Suppression...
        if self.zeros == 'trailing':
            num = num.rstrip('0')

        elif self.zeros == 'leading':
            num = num.lstrip('0')

        # Edge case. Per Gerber spec if the value is 0 we should return a single '0' in all cases, see page 77.
        elif not num.strip('0'):
            num = '0'

        return sign + (num or '0')

    def write_excellon_value(self, value, unit=None):
        if unit is not None:
            value = self.unit(value, unit)
        
        integer_digits, decimal_digits = self.number_format
        if integer_digits is None:
            integer_digits = 2
        if decimal_digits is None:
            decimal_digits = 6

        return format(value, f'0{integer_digits+decimal_digits+1}.{decimal_digits}f')


class Polyline:
    """ Class that is internally used to generate compact SVG renderings. Collectes a number of subsequent
    :py:class:`~.graphic_objects.Line` and :py:class:`~.graphic_objects.Arc` instances into one SVG <path>. """

    def __init__(self, *lines):
        self.coords = []
        self.polarity_dark = None
        self.width = None

        for line in lines:
            self.append(line)

    def append(self, line):
        assert isinstance(line, Line)
        if not self.coords:
            self.coords.append((line.x1, line.y1))
            self.coords.append((line.x2, line.y2))
            self.polarity_dark = line.polarity_dark
            self.width = line.width
            return True

        else:
            x, y = self.coords[-1]
            if self.polarity_dark == line.polarity_dark and self.width == line.width \
                    and math.isclose(line.x1, x) and math.isclose(line.y1, y):
                self.coords.append((line.x2, line.y2))
                return True

            else:
                return False

    def to_svg(self, fg='black', bg='white', tag=Tag):
        color = fg if self.polarity_dark else bg
        if not self.coords:
            return None

        (x0, y0), *rest = self.coords
        d = f'M {x0:.6} {y0:.6} ' + ' '.join(f'L {x:.6} {y:.6}' for x, y in rest)
        width = f'{self.width:.6}' if not math.isclose(self.width, 0) else '0.01mm'
        return tag('path', d=d, style=f'fill: none; stroke: {color}; stroke-width: {width}; stroke-linejoin: round; stroke-linecap: round')


class CamFile:
    def __init__(self, original_path=None, layer_name=None, import_settings=None):
        self.original_path = original_path
        self.layer_name = layer_name
        self.import_settings = import_settings

    def to_svg(self, margin=0, arg_unit=MM, svg_unit=MM, force_bounds=None, fg='black', bg='white', tag=Tag):

        if force_bounds is None:
            (min_x, min_y), (max_x, max_y) = self.bounding_box(svg_unit, default=((0, 0), (0, 0)))
        else:
            (min_x, min_y), (max_x, max_y) = force_bounds
            min_x = svg_unit(min_x, arg_unit)
            min_y = svg_unit(min_y, arg_unit)
            max_x = svg_unit(max_x, arg_unit)
            max_y = svg_unit(max_y, arg_unit)

        content_min_x, content_min_y = min_x, min_y
        content_w, content_h = max_x - min_x, max_y - min_y
        if margin:
            margin = svg_unit(margin, arg_unit)
            min_x -= margin
            min_y -= margin
            max_x += margin
            max_y += margin

        w, h = max_x - min_x, max_y - min_y
        w = 1.0 if math.isclose(w, 0.0) else w
        h = 1.0 if math.isclose(h, 0.0) else h

        view = tag('sodipodi:namedview', [], id='namedview1', pagecolor=bg,
                inkscape__document_units=svg_unit.shorthand)

        tags = []
        polyline = None
        for i, obj in enumerate(self.objects):
            #if isinstance(obj, go.Flash):
            #    if polyline:
            #        tags.append(polyline.to_svg(tag, fg, bg))
            #        polyline = None

            #    mask_tags = [ prim.to_svg(tag, 'white', 'black') for prim in obj.to_primitives(unit=svg_unit) ]
            #    mask_tags.insert(0, tag('rect', width='100%', height='100%', fill='black'))
            #    mask_id = f'mask{i}'
            #    tag('mask', mask_tags, id=mask_id)
            #    tag('rect', width='100%', height='100%', mask='url(#{mask_id})', fill=fg)

            #else:
                for primitive in obj.to_primitives(unit=svg_unit):
                    if isinstance(primitive, gp.Line):
                        if not polyline:
                            polyline = gp.Polyline(primitive)
                        else:
                            if not polyline.append(primitive):
                                tags.append(polyline.to_svg(fg, bg, tag=tag))
                                polyline = gp.Polyline(primitive)
                    else:
                        if polyline:
                            tags.append(polyline.to_svg(fg, bg, tag=tag))
                            polyline = None
                        tags.append(primitive.to_svg(fg, bg, tag=tag))
        if polyline:
            tags.append(polyline.to_svg(fg, bg, tag=tag))

        # setup viewport transform flipping y axis
        xform = f'translate({content_min_x} {content_min_y+content_h}) scale(1 -1) translate({-content_min_x} {-content_min_y})'

        svg_unit = 'in' if svg_unit == 'inch' else 'mm'
        # TODO export apertures as <uses> where reasonable.
        return tag('svg', [view, tag('g', tags, transform=xform)],
                width=f'{w}{svg_unit}', height=f'{h}{svg_unit}',
                viewBox=f'{min_x} {min_y} {w} {h}',
                xmlns="http://www.w3.org/2000/svg",
                xmlns__xlink="http://www.w3.org/1999/xlink",
                xmlns__sodipodi='http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd',
                xmlns__inkscape='http://www.inkscape.org/namespaces/inkscape',
                root=True)

    def size(self, unit=MM):
        (x0, y0), (x1, y1) = self.bounding_box(unit, default=((0, 0), (0, 0)))
        return (x1 - x0, y1 - y0)

    def bounding_box(self, unit=MM, default=None):
        """ Calculate bounding box of file. Returns value given by 'default' argument when there are no graphical
        objects (default: None)
        """
        bounds = [ p.bounding_box(unit) for p in self.objects ]
        if not bounds:
            return default

        min_x = min(x0 for (x0, y0), (x1, y1) in bounds)
        min_y = min(y0 for (x0, y0), (x1, y1) in bounds)
        max_x = max(x1 for (x0, y0), (x1, y1) in bounds)
        max_y = max(y1 for (x0, y0), (x1, y1) in bounds)

        #for p in self.objects:
        #    bb = (o_min_x, o_min_y), (o_max_x, o_max_y) = p.bounding_box(unit)
        #    if o_min_x == min_x or o_min_y == min_y or o_max_x == max_x or o_max_y == max_y:
        #        print('\033[91m  bounds\033[0m', bb, p)

        return ((min_x, min_y), (max_x, max_y))