53 lines
1.6 KiB
Python
53 lines
1.6 KiB
Python
from typing import Any, Iterable, List, Optional, Tuple
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from pdfminer import settings
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from pdfminer.pdfparser import PDFSyntaxError
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from pdfminer.pdftypes import list_value, int_value, dict_value
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from pdfminer.utils import choplist
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class NumberTree:
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"""A PDF number tree.
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See Section 3.8.6 of the PDF Reference.
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"""
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def __init__(self, obj: Any):
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self._obj = dict_value(obj)
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self.nums: Optional[Iterable[Any]] = None
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self.kids: Optional[Iterable[Any]] = None
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self.limits: Optional[Iterable[Any]] = None
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if "Nums" in self._obj:
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self.nums = list_value(self._obj["Nums"])
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if "Kids" in self._obj:
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self.kids = list_value(self._obj["Kids"])
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if "Limits" in self._obj:
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self.limits = list_value(self._obj["Limits"])
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def _parse(self) -> List[Tuple[int, Any]]:
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items = []
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if self.nums: # Leaf node
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for k, v in choplist(2, self.nums):
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items.append((int_value(k), v))
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if self.kids: # Root or intermediate node
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for child_ref in self.kids:
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items += NumberTree(child_ref)._parse()
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return items
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values: List[Tuple[int, Any]] # workaround decorators unsupported by mypy
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@property # type: ignore[no-redef,misc]
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def values(self) -> List[Tuple[int, Any]]:
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values = self._parse()
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if settings.STRICT:
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if not all(a[0] <= b[0] for a, b in zip(values, values[1:])):
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raise PDFSyntaxError("Number tree elements are out of order")
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else:
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values.sort(key=lambda t: t[0])
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return values
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