io_import_dxf/dxfgrabber/tablessection.py

   1 # SPDX-FileCopyrightText: 2012 Manfred Moitzi (mozman)
   2 #
   3 # SPDX-License-Identifier: MIT
   4
   5 # Purpose: handle tables section
   6 # Created: 21.07.2012, taken from my ezdxf project
   7
   8 from __future__ import unicode_literals
   9 __author__ = "mozman <mozman@gmx.at>"
  10
  11 from .defaultchunk import iterchunks, DefaultChunk
  12 from .layers import LayerTable
  13 from .styles import StyleTable
  14 from .linetypes import LinetypeTable
  15
  16 TABLENAMES = {
  17     'layer': 'layers',
  18     'ltype': 'linetypes',
  19     'appid': 'appids',
  20     'dimstyle': 'dimstyles',
  21     'style': 'styles',
  22     'ucs': 'ucs',
  23     'view': 'views',
  24     'vport': 'viewports',
  25     'block_record': 'block_records',
  26     }
  27
  28
  29 def tablename(dxfname):
  30     """ Translate DXF-table-name to attribute-name. ('LAYER' -> 'layers') """
  31     name = dxfname.lower()
  32     return TABLENAMES.get(name, name+'s')
  33
  34
  35 class DefaultDrawing(object):
  36     dxfversion = 'AC1009'
  37     encoding = 'cp1252'
  38
  39
  40 class TablesSection(object):
  41     name = 'tables'
  42
  43     def __init__(self):
  44         self._tables = dict()
  45         self._create_default_tables()
  46
  47     def _create_default_tables(self):
  48         for cls in TABLESMAP.values():
  49             table = cls()
  50             self._tables[table.name] = table
  51
  52     @staticmethod
  53     def from_tags(tags, drawing):
  54         tables_section = TablesSection()
  55         tables_section._setup_tables(tags)
  56         return tables_section
  57
  58     def _setup_tables(self, tags):
  59         def name(table):
  60             return table[1].value
  61
  62         def skiptags(tags, count):
  63             for i in range(count):
  64                 next(tags)
  65             return tags
  66
  67         itertags = skiptags(iter(tags), 2)  # (0, 'SECTION'), (2, 'TABLES')
  68         for table in iterchunks(itertags, stoptag='ENDSEC', endofchunk='ENDTAB'):
  69             table_class = table_factory(name(table))
  70             if table_class is not None:
  71                 new_table = table_class.from_tags(table)
  72                 self._tables[new_table.name] = new_table
  73
  74     def __getattr__(self, key):
  75         try:
  76             return self._tables[key]
  77         except KeyError:
  78             raise AttributeError(key)
  79
  80 # support for further tables types are possible
  81 TABLESMAP = {
  82     'LAYER': LayerTable,
  83     'STYLE': StyleTable,
  84     'LTYPE': LinetypeTable,
  85 }
  86
  87
  88 def table_factory(name):
  89     return TABLESMAP.get(name, None)