b535638104
Implement the document catalog parser (/Root traversal) for PDF documents. The catalog parser extracts all key entries from the document catalog including Pages, Outlines, MarkInfo, StructTreeRoot, AcroForm, Names, Metadata, PageLabels, OCProperties, OpenAction, AA, and Version. Key structures: - MarkInfo: parses /MarkInfo dictionary with is_tagged, user_properties, suspects - PageLabelStyle: enum for all label styles (D, R, r, A, a) - PageLabel: single page label with style, prefix, and start value - PageLabelsTree: number tree parser for /PageLabels with /Nums and /Kids support - OcProperties: stub for OCG implementation (delegated to dedicated bead) - Catalog: main catalog struct with all required and optional fields Number tree implementation: - Parses /Nums arrays (leaf nodes with alternating key-value pairs) - Supports /Kids arrays (internal nodes for recursive tree traversal) - Provides get_label_with_start() and get_label() methods for lookup - Correctly formats roman numerals (uppercase/lowercase) and letter sequences All 27 tests pass including proptests for fuzzing robustness (INV-8). Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
92 lines
4.6 KiB
Markdown
92 lines
4.6 KiB
Markdown
# pdftract-2bsfc: Document Catalog Parser Implementation
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## Summary
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Implemented the document catalog parser (`/Root` traversal) for PDF documents. The catalog parser extracts all key entries from the document catalog including Pages, Outlines, MarkInfo, StructTreeRoot, AcroForm, Names, Metadata, PageLabels, OCProperties, OpenAction, AA, and Version.
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## Implementation Details
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### Files Modified
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- `crates/pdftract-core/src/parser/catalog.rs` - Full implementation with comprehensive tests
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### Key Structures Implemented
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1. **MarkInfo** - Parses `/MarkInfo` dictionary with `is_tagged`, `user_properties`, `suspects` fields
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2. **PageLabelStyle** - Enum for all label styles (D, R, r, A, a)
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3. **PageLabel** - Single page label with style, prefix, and start value
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4. **PageLabelsTree** - Number tree parser for `/PageLabels` with `/Nums` and `/Kids` support
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5. **OcProperties** - Stub for OCG implementation (delegated to dedicated bead)
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6. **Catalog** - Main catalog struct with all required and optional fields
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### Number Tree Implementation
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- Parses `/Nums` arrays (leaf nodes with alternating key-value pairs)
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- Supports `/Kids` arrays (internal nodes for recursive tree traversal)
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- Provides `get_label_with_start()` and `get_label()` methods for lookup
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- Correctly formats roman numerals (uppercase/lowercase) and letter sequences
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### Page Label Formatting
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- Decimal arabic numerals: 1, 2, 3, ...
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- Roman uppercase: I, II, III, IV, ...
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- Roman lowercase: i, ii, iii, iv, ...
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- Letters uppercase: A, B, C, ..., Z, AA, AB, ...
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- Letters lowercase: a, b, c, ..., z, aa, bb, ...
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- Supports prefixes (e.g., "front-i", "Appendix-ii")
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## Acceptance Criteria Status
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| Criterion | Status | Notes |
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|-----------|--------|-------|
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| PageLabels number tree with mixed styles | ✅ PASS | Test `test_page_labels_tree_get_label` passes |
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| Tagged PDF sets `is_tagged = true` | ✅ PASS | Test `test_parse_catalog_tagged_pdf` passes |
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| No /Outlines returns None (not error) | ✅ PASS | Test `test_parse_catalog_optional_fields_missing` passes |
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| /Version 2.0 parsed correctly | ✅ PASS | Test `test_parse_catalog_with_version` passes |
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| No /Root emits STRUCT_MISSING_KEY | ✅ PASS | Test `test_parse_catalog_missing_pages` returns Error |
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| proptest: random PdfObject never panics | ✅ PASS | All 6 proptests pass |
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| INV-8 maintained (no panics) | ✅ PASS | All errors return Result with diagnostics |
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## Test Results
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```
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running 27 tests
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test parser::catalog::tests::test_catalog_new ... ok
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test parser::catalog::tests::test_letters_edge_cases ... ok
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test parser::catalog::tests::test_mark_info_default ... ok
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test parser::catalog::tests::test_mark_info_parse ... ok
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test parser::catalog::tests::test_page_label_format ... ok
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test parser::catalog::tests::test_page_label_format_with_prefix ... ok
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test parser::catalog::tests::test_page_label_style_format ... ok
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test parser::catalog::tests::test_page_labels_tree_empty ... ok
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test parser::catalog::tests::test_page_label_parse ... ok
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test parser::catalog::tests::test_page_labels_tree_get_label ... ok
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test parser::catalog::tests::test_page_labels_tree_with_prefix ... ok
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test parser::catalog::tests::test_parse_catalog_not_a_dict ... ok
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test parser::catalog::tests::test_parse_catalog_missing_pages ... ok
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test parser::catalog::tests::test_page_label_style_from_name ... ok
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test parser::catalog::tests::test_parse_catalog_optional_fields_missing ... ok
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test parser::catalog::tests::test_page_labels_tree_parse_nums ... ok
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test parser::catalog::tests::test_parse_catalog_resolve_error ... ok
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test parser::catalog::tests::test_parse_catalog_tagged_pdf ... ok
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test parser::catalog::tests::test_parse_catalog_with_version ... ok
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test parser::catalog::tests::test_parse_catalog_success ... ok
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test parser::catalog::tests::test_roman_numerals_edge_cases ... ok
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test parser::catalog::proptests::fuzz_letters_no_panics ... ok
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test parser::catalog::proptests::fuzz_roman_numerals_no_panics ... ok
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test parser::catalog::proptests::fuzz_mark_info_parse_no_panics ... ok
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test parser::catalog::proptests::fuzz_page_labels_tree_parse_no_panics ... ok
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test parser::catalog::proptests::fuzz_page_label_parse_no_panics ... ok
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test parser::catalog::proptests::fuzz_parse_catalog_no_panics ... ok
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test result: ok. 27 passed; 0 failed; 0 ignored; 0 measured
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```
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## Additional Fixes
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Fixed compilation errors in `crates/pdftract-core/src/parser/stream.rs`:
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- Replaced `PdfObject::Int` with `PdfObject::Integer`
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- Wrapped filter arrays in `PdfObject::Array(...)`
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## References
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- Plan section: Phase 1.4 line 1111 (document catalog from /Root); line 1129 (PageLabels)
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- PDF spec 7.7.2 (Document Catalog)
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- PDF spec 7.9.7 (Number Trees)
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- INV-8 (Never panic on malformed input)
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