def UNORM(ld: LogicalData) -> int:
"""
Representation code 16, Unsigned 2-byte integer.
[RP66V1 Appendix B Section B.16]
"""
ret = ld.read()
ret <<= 8
ret |= ld.read()
return ret
def __init__(self, ld: LogicalData, template: Template):
component_descriptor = ComponentDescriptor(ld.read())
if not component_descriptor.is_object:
raise ExceptionEFLRObject(
f'Component Descriptor does not represent a object but a {component_descriptor.type}.'
)
self.name: RepCode.ObjectName = RepCode.OBNAME(ld)
self.attrs: typing.List[typing.Union[AttributeBase, None]] = []
self.attr_label_map: typing.Dict[bytes, int] = {}
index: int = 0
while True:
component_descriptor = ComponentDescriptor(ld.read())
if not component_descriptor.is_attribute_group:
raise ExceptionEFLRObject(
f'Component Descriptor does not represent a attribute but a {component_descriptor.type}.'
)
if template[index].component_descriptor.is_invariant_attribute:
self.attrs.append(template[index])
elif template[index].component_descriptor.is_absent_attribute:
self.attrs.append(None)
else:
# TODO: Check the attribute label is the same as the template. Reference [RP66V1 Section 4.5]
self.attrs.append(
Attribute(component_descriptor, ld, template[index]))
if ld.remain == 0 or ComponentDescriptor(ld.peek()).is_object:
break
# next_component_descriptor = ComponentDescriptor(ld.peek())
# if next_component_descriptor.is_object:
# break
index += 1
while len(self.attrs) < len(template):
self.attrs.append(template[len(self.attrs)])
if len(template) != len(self.attrs):
raise ExceptionEFLRObject(
f'Template specifies {len(template)} attributes but Logical Data has {len(self.attrs)}'
)
# Now populate self.attr_label_map
for a, attr in enumerate(self.attrs):
if attr is None:
label = template.attrs[a].label
else:
label = attr.label
# TODO: Assert that the attribute label is the same as the template. Reference [RP66V1 Section 4.5]
if label in self.attr_label_map:
raise ExceptionEFLRObjectDuplicateLabel(
f'Duplicate Attribute label {label}')
self.attr_label_map[label] = a
def SSHORT(ld: LogicalData) -> int:
"""
SSHORT Representation code 12, Signed 1-byte integer.
[RP66V1 Appendix B Section B.12]
"""
r = ld.read()
if r > 127:
r -= 256
return r
def __init__(self, ld: LogicalData):
ld_index = ld.index
component_descriptor = ComponentDescriptor(ld.read())
if not component_descriptor.is_set_group:
raise ExceptionEFLRSet(f'Component Descriptor does not represent a set but a {component_descriptor.type}.')
self.type: bytes = RepCode.IDENT(ld)
self.name: bytes = ComponentDescriptor.CHARACTERISTICS_AND_COMPONENT_FORMAT_SET_MAP['N'].global_default
if component_descriptor.has_set_N:
self.name = RepCode.IDENT(ld)
self.logical_data_consumed = ld.index - ld_index
def __init__(self, ld: LogicalData):
# TODO: Check ranges
self.year: int = USHORT(ld) + 1900
v: int = ld.read()
self.tz: int = (v >> 4) & 0xf
self.month: int = v & 0xf
self.day: int = USHORT(ld)
self.hour: int = USHORT(ld)
self.minute: int = USHORT(ld)
self.second: int = USHORT(ld)
self.millisecond: int = UNORM(ld)
def UVARI(ld: LogicalData) -> int:
"""
Representation code 18, Variable-length unsigned integer.
[RP66V1 Appendix B Section B.18]
"""
value: int = ld.read()
if value & 0xc0 == 0x80:
# Two bytes
value &= 0x7f
value <<= 8
value |= ld.read()
# TODO: Raise if < 2**7
elif value & 0xc0 == 0xc0:
# Four bytes
value &= 0x3f
value <<= 8
value |= ld.read()
value <<= 8
value |= ld.read()
value <<= 8
value |= ld.read()
# TODO: Raise if < 2**14
return value
def read(self, ld: LogicalData):
"""Populate the template with the Logical Data."""
while True:
component_descriptor = ComponentDescriptor(ld.read())
if not component_descriptor.is_attribute_group:
raise ExceptionEFLRTemplate(
f'Component Descriptor does not represent a attribute but a {component_descriptor.type}.'
)
template_attribute = TemplateAttribute(component_descriptor, ld)
if template_attribute.label in self.attr_label_map:
raise ExceptionEFLRTemplateDuplicateLabel(f'Duplicate template label {template_attribute.label}')
self.attr_label_map[template_attribute.label] = len(self.attrs)
self.attrs.append(template_attribute)
if ld.remain == 0:
# This is kind of unusual, it is an EFLR with a template but no objects.
break
next_component_descriptor = ComponentDescriptor(ld.peek())
if next_component_descriptor.is_object:
break
def USHORT(ld: LogicalData) -> int:
"""
USHORT Representation code 15, Unsigned 1-byte integer.
[RP66V1 Appendix B Section B.15]
"""
return ld.read()
def _pascal_string(ld: LogicalData) -> bytes:
"""Reads a Pascal like string from the LogicalData."""
siz: int = ld.read()
return ld.chunk(siz)