--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/header.py Sat May 25 09:41:33 2019 +0200
@@ -0,0 +1,138 @@
+import re
+import linetypes
+
+class Header:
+ def __init__(self):
+ self.description = None
+ self.name = None
+ self.author = None
+ self.username = None
+ self.filetype = None
+ self.qualifiers = None
+ self.license = None
+ self.help = []
+ self.bfc = None
+ self.category = None
+ self.keywords = []
+ self.cmdline = None
+ self.history = []
+
+class BadHeader:
+ def __init__(self, index, reason):
+ self.index = index
+ self.reason = reason
+ def __repr__(self):
+ return str.format(
+ 'header.BadHeader(index = {index!r}, reason = {reason!r})',
+ index = self.index,
+ reason = self.reason,
+ )
+
+geometrical_types = [
+ linetypes.LineSegment,
+ linetypes.Triangle,
+ linetypes.Quadrilateral,
+ linetypes.ConditionalLine,
+]
+
+def is_suitable_header_object(entry):
+ return not any(
+ isinstance(entry, linetype)
+ for linetype in [
+ *geometrical_types,
+ linetypes.Comment,
+ linetypes.Error,
+ ]
+ )
+
+class HeaderError(Exception):
+ def __init__(self, index, reason):
+ self.index, self.reason = index, reason
+ def __repr__(self):
+ return str.format(
+ 'HeaderError({index!r}, {reason!r})',
+ index = self.index,
+ reason = self.reason,
+ )
+ def __str__(self):
+ return reason
+
+class HeaderParser:
+ def __init__(self):
+ self.model_body = None
+ self.cursor = 0
+ self.problems = []
+ def parse(self, model_body):
+ result = Header()
+ self.order = []
+ self.cursor = -1
+ self.model_body = model_body
+ self.skip_to_next()
+ result.description = self.current()
+ self.skip_to_next()
+ result.name = self.parse_pattern('^Name: (.+)$', 'name')[0]
+ self.skip_to_next()
+ result.author = self.parse_pattern('^Author: (.+)$', 'author')[0]
+ for header_entry in self.get_more_header_stuff():
+ if self.try_to_match(
+ '^!LDRAW_ORG ' +
+ '(' \
+ '(?:Unofficial_)?' \
+ 'Part|' \
+ 'Subpart|' \
+ 'Primitive|' \
+ '8_Primitive|' \
+ '48_Primitive|' \
+ 'Shortcut' \
+ ')\s?' \
+ '(ORIGINAL|UPDATE \d\d\d\d-\d\d)?$',
+ 'part type'):
+ result.filetype, result.qualifiers = self.groups
+ elif self.try_to_match(
+ '^!LICENSE (.+)$',
+ 'license'):
+ result.license = self.groups()
+ else:
+ self.parse_error("couldn't handle header metacommand: " + repr(header_entry.text))
+ return {
+ 'header': result,
+ 'end-index': self.cursor + 1,
+ }
+ def parse_error(self, message):
+ raise HeaderError(index = self.cursor, reason = message)
+ def get_more_header_stuff(self):
+ while True:
+ self.cursor += 1
+ if self.cursor >= len(self.model_body):
+ break
+ entry = self.model_body[self.cursor]
+ if not is_suitable_header_object(entry):
+ break
+ if isinstance(entry, linetypes.MetaCommand):
+ yield entry
+ def skip_to_next(self, *, spaces_expected = 0):
+ while True:
+ if self.cursor + 1 >= len(self.model_body):
+ self.parse_error('stub ldraw file')
+ self.cursor += 1
+ entry = self.model_body[self.cursor]
+ if not is_suitable_header_object(entry):
+ self.parse_error('header is incomplete')
+ if isinstance(entry, linetypes.MetaCommand):
+ return
+ def try_to_match(self, pattern, patterntype):
+ try:
+ self.groups = self.parse_pattern(pattern, patterntype)
+ except:
+ return False
+ def current(self):
+ entry = self.model_body[self.cursor]
+ assert isinstance(entry, linetypes.MetaCommand)
+ return entry.text
+ def parse_pattern(self, pattern, description):
+ match = re.search(pattern, self.current())
+ if match:
+ self.order.append(description)
+ return match.groups()
+ else:
+ self.parse_error(str.format("couldn't parse {}", description))