file.mvd attr available in spf parser

Author: Ghesselink

__init__.py

@@ -10,7 +10,7 @@
 
 from lark import Lark, Transformer, Tree, Token
 from lark.exceptions import UnexpectedToken, UnexpectedCharacters
-
+from ifcopenshell.util.mvd_info import MvdInfo, LARK_AVAILABLE
 
 class ValidationError(Exception):
     pass
@@ -484,6 +484,13 @@ def header(self):
             header[field_name.lower()] = namedtuple_class(*field_data)
 
         return types.SimpleNamespace(**header)
+    
+    
+    @property
+    def mvd(self):
+        if not LARK_AVAILABLE or MvdInfo is None:
+            return None
+        return MvdInfo(self.header)
 
     def __getitem__(self, key: numbers.Integral) -> entity_instance:
         return self.by_id(key)

mvd_info.py

@@ -0,0 +1,325 @@
+try:
+    from lark import Lark, Transformer
+    from lark.exceptions import UnexpectedCharacters, UnexpectedEOF, UnexpectedToken
+    LARK_AVAILABLE = True
+except ImportError:
+    LARK_AVAILABLE = False
+
+import re
+
+if LARK_AVAILABLE:
+    mvd_grammar = r'''
+        start: entry+
+
+        entry: "ViewDefinition" "[" simple_value_list "]"   -> view_definition
+            | "Comment" "[" simple_value_list "]" -> comment
+            | "ExchangeRequirement" "[" other_keyword "]" -> exchangerequirement
+            | "Option" "[" other_keyword "]" -> option
+            | GENERIC_KEYWORD "[" dynamic_option_word "]" -> dynamic_option
+
+        GENERIC_KEYWORD: /[A-Za-z0-9_]+/
+
+        simple_value_list: value ("," value)*
+
+        value_list_set: value_set (";" value_set)*
+
+        value_set: set_name ":" simple_value_list
+
+        set_name: /[A-Za-z0-9_]+/
+
+        value: /[A-Za-z0-9 _\.-]+/
+
+        other_keyword: /[^\[\]]+/  
+        
+        dynamic_option_word: /[^\[\]]+/ 
+
+        %import common.WS
+        %ignore WS
+    '''
+
+    parser = Lark(mvd_grammar, parser='lalr')
+
+    class DescriptionTransform(Transformer):
+        def __init__(self):
+            self.view_definitions = []
+            self.keywords = set()
+            self.comments = ""
+            self.exchange_requirements = ""
+            self.options = ""
+            self._dynamic = {}
+
+        def view_definition(self, args):
+            self.keywords.add('view_definitions')
+            self.view_definitions.extend(args[0])
+
+        def store_text_attribute(self, args, keyword):
+            self.keywords.add(keyword)
+            setattr(self, keyword, " ".join(" ".join(str(child) for child in args[0].children).split()))
+
+        def comment(self, args):
+            self.keywords.add("comments")
+            self.comments = args[0] if len(args[0]) > 1 else args[0][0]
+
+        def exchangerequirement(self, args):
+            self.store_text_attribute(args, "exchange_requirements")
+
+        def option(self, args):
+            if v := parse_semicolon_separated_kv(" ".join(" ".join(str(child) for child in args[0].children).split())):
+                setattr(self, 'options', v)
+            else:
+                self.store_text_attribute(args, "options")
+
+        def dynamic_option(self, args):
+            try:
+                original_keyword = str(args[0])  
+                key = original_keyword.lower()   
+                raw_text = args[1].children[0].value
+                parsed_value = parse_semicolon_separated_kv(raw_text)
+                self._dynamic[key] = (parsed_value, original_keyword)  
+                self.keywords.add(key)
+                setattr(self, key, parsed_value)
+            except Exception:
+                setattr(self, key, None)
+
+        def simple_value_list(self, args):
+            return [str(arg) for arg in args]
+
+        def value_list_set(self, args):
+            return args
+
+        def value_set(self, args):
+            return [str(args[0])] + args[1]
+
+        def value(self, args):
+            return str(args[0])
+
+        def set_name(self, args):
+            return str(args[0])
+
+    def parse_mvd(description):
+        text = ' '.join(description)
+        parsed_description = DescriptionTransform()
+        try:
+            if not text:
+                parsed_description.view_definitions = None
+                return parsed_description
+            parse_tree = parser.parse(text)
+            parsed_description.transform(parse_tree)
+        except (UnexpectedCharacters, UnexpectedEOF, UnexpectedToken):
+            parsed_description.view_definitions = None
+        return parsed_description
+
+    def parse_semicolon_separated_kv(text: str) -> dict[str, str | list[str]] | None:
+        if not re.search(r'\w+\s*:\s*[^:]+', text):
+            return None
+        result = {}
+        try:
+            pairs = text.split(';')
+            for pair in pairs:
+                if ':' in pair:
+                    key, value = pair.split(':', 1)
+                    key = key.strip()
+                    values = [v.strip() for v in value.split(',')]
+                    result[key] = values[0] if len(values) == 1 else values
+            return result
+        except Exception:
+            return None
+else:
+    def parse_mvd(description):
+        return None
+
+
+class MvdInfo:
+    def __init__(self, header):
+        self._header = header
+        self._parsed = None
+
+    def _ensure_parsed(self):
+        if not LARK_AVAILABLE:
+            return
+        if self._parsed is None:
+            description = self._header.file_description.description
+            if not description:
+                self._parsed = DescriptionTransform() # avoid AttributeError
+            else:
+                self._parsed = parse_mvd(description)
+
+    @property
+    def description(self) -> list[str]:
+        return self._header.file_description.description
+
+    @description.setter
+    def description(self, new_description: list[str]):
+        self._header.file_description.description = tuple(new_description)
+        self._parsed = None
+
+    @property
+    def view_definitions(self):
+        self._ensure_parsed()
+        if not self._parsed or self._parsed.view_definitions is None:
+            return None  #
+
+        vd = self._parsed.view_definitions
+        vd_list = vd if isinstance(vd, list) else [vd] if vd else []
+        return AutoCommitList(
+            vd_list,
+            callback=lambda val: (self._update_keyword("ViewDefinition", val), setattr(self, "_parsed", None)),
+            formatter=lambda lst: ",".join(str(i) for i in lst)
+        )
+
+    @view_definitions.setter
+    def view_definitions(self, new_value: str | list[str]):
+        if isinstance(new_value, list):
+            value = ", ".join(new_value)
+        else:
+            value = str(new_value)
+        self._update_keyword("ViewDefinition", value)
+
+    @property
+    def comments(self):
+        self._ensure_parsed()
+        comments = self._parsed.comments
+        comment_list = comments if isinstance(comments, list) else [comments] if comments else []
+        return AutoCommitList(
+            comment_list,
+            callback=lambda val: self._update_keyword("Comment", val),
+            formatter=lambda lst: ", ".join(str(i) for i in lst)
+        )
+
+    @comments.setter
+    def comments(self, new_value: str | list[str]):
+        if isinstance(new_value, list):
+            value = ", ".join(new_value)
+        else:
+            value = str(new_value)
+        self._update_keyword("Comment", value)
+
+    @property
+    def exchange_requirements(self):
+        self._ensure_parsed()
+        return self._parsed.exchange_requirements if self._parsed else None
+
+    @exchange_requirements.setter
+    def exchange_requirements(self, new_value: str):
+        self._update_keyword("ExchangeRequirement", new_value)
+
+    @property
+    def options(self):
+        self._ensure_parsed()
+        if isinstance(self._parsed.options, dict):
+            return DictionaryHandler(self._parsed.options, self, "Option")
+        return self._parsed.options if self._parsed else None
+
+    @options.setter
+    def options(self, new_value: str):
+        self._update_keyword("Option", new_value)
+
+    @property
+    def keywords(self):
+        self._ensure_parsed()
+        return self._parsed.keywords if self._parsed else set()
+
+    def _update_keyword(self, keyword: str, new_value: str):
+        updated = False
+        new_line = f"{keyword} [{new_value}]"
+        lines = []
+        for line in self.description:
+            if line.strip().startswith(f"{keyword} ["):
+                lines.append(new_line)
+                updated = True
+            else:
+                lines.append(line)
+        if not updated:
+            lines.append(new_line)
+        self.description = lines
+
+    def __getattr__(self, name):
+        self._ensure_parsed()
+        if hasattr(self._parsed, '_dynamic'):
+            name_lc = name.lower()
+            if name_lc in self._parsed._dynamic:
+                value, original_keyword = self._parsed._dynamic[name_lc]
+                return DictionaryHandler(value, self, original_keyword)
+        raise AttributeError(f"'MvdInfo' object has no attribute '{name}'")
+
+    def __dir__(self):
+        base = super().__dir__()
+        if self._parsed and hasattr(self._parsed, '_dynamic'):
+            return base + [kw for _, kw in self._parsed._dynamic.values()]
+        return base
+
+
+class DictionaryHandler(dict):
+    def __init__(self, initial_data, mvdinfo, keyword):
+        super().__init__()
+        self._mvdinfo = mvdinfo
+        self._keyword = keyword
+        for k, v in initial_data.items():
+            if isinstance(v, list):
+                super().__setitem__(k, AutoCommitList(v, self._commit))
+            else:
+                super().__setitem__(k, v)
+
+    def _commit(self):
+        new_value = "; ".join(
+            f"{k}: {', '.join(v) if isinstance(v, list) else v}"
+            for k, v in self.items()
+        )
+        self._mvdinfo._update_keyword(self._keyword, new_value)
+
+    def __setitem__(self, key, value):
+        if isinstance(value, list):
+            value = AutoCommitList(value, self._commit)
+        super().__setitem__(key, value)
+        self._commit()
+
+    def __delitem__(self, key):
+        super().__delitem__(key)
+        self._commit()
+
+
+class AutoCommitList(list):
+    "ensures keyword attributes are written back to ifcopenshell.file.header"
+    def __init__(self, iterable, callback, formatter=None):
+        super().__init__(iterable)
+        self._callback = callback
+        self._formatter = formatter  
+
+    def _commit(self):
+        if self._formatter:
+            self._callback(self._formatter(self))
+        else:
+            self._callback()
+
+    def append(self, item):
+        super().append(item)
+        self._commit()
+
+    def extend(self, iterable):
+        super().extend(iterable)
+        self._commit()
+
+    def insert(self, index, item):
+        super().insert(index, item)
+        self._commit()
+
+    def remove(self, item):
+        super().remove(item)
+        self._commit()
+
+    def pop(self, index=-1):
+        item = super().pop(index)
+        self._commit()
+        return item
+
+    def clear(self):
+        super().clear()
+        self._commit()
+
+    def __setitem__(self, index, value):
+        super().__setitem__(index, value)
+        self._commit()
+
+    def __delitem__(self, index):
+        super().__delitem__(index)
+        self._commit()

test_parser.py

@@ -64,4 +64,43 @@ def test_parse_valid_header():
 
     for key, val in expected_schema.items():
         assert getattr(f.header.file_schema, key) == val, f"{key} mismatch"
+        
 
+def test_header_only_api():
+    f = open('fixtures/passing_header.ifc', only_header=True)
+    expected_description = {
+        "description": ('ViewDefinition [Alignment-basedView]',),
+        "implementation_level": '2;1',
+    }
+
+    expected_name = {
+        "name": 'Header example2.ifc',
+        "time_stamp": '2022-09-16T10:35:07',
+        "author": ('Evandro Alfieri',),
+        "organization": ('buildingSMART Int.',),
+        "preprocessor_version": 'IFC Motor 1.0',
+        "originating_system": 'Company - Application - 26.0.0.0',
+        "authorization": 'none',
+    }
+
+    expected_schema = {
+        "schema_identifiers": ('IFC4X3_ADD2',),
+    }
+
+    for key, val in expected_description.items():
+        assert getattr(f.header.file_description, key) == val, f"{key} mismatch"
+
+    for key, val in expected_name.items():
+        assert getattr(f.header.file_name, key) == val, f"{key} mismatch"
+
+    for key, val in expected_schema.items():
+        assert getattr(f.header.file_schema, key) == val, f"{key} mismatch"
+
+def test_file_mvd_attr():
+    f = open('fixtures/extended_mvd.ifc', only_header=True)
+    
+    assert 'ReferenceView_V1.2' in f.mvd.view_definitions
+    assert all(i in f.mvd.keywords for i in ['exchange_requirements', 'view_definitions', 'remark', 'comments'])
+    assert 'Ramp' in f.mvd.options['ExcludedObjects']
+    assert f.mvd.Remark['SomeKey'] == 'SomeValue'
+    assert len(f.mvd.comments) == 2