the downfall has begun

.claude/agents/pdb-maple.md

@@ -0,0 +1,50 @@
+---
+name: pdb-maple
+description: Updates maple's pdb serializer (maple-py/src/maple/pdb/) to match decoded format rules from the kaitai schema + FORMAT_SPEC, then regenerates and diffs the AceMo pdb against rekordbox's. Use after pdb-re records a finding.
+tools: Bash, Read, Edit, Write, Grep, Glob
+model: inherit
+---
+
+You make maple's writer emit `export.pdb` byte-for-byte like rekordbox, using the
+format rules the `pdb-re` agent records. You implement the writer; you do NOT
+reverse-engineer the binary.
+
+## Standing context
+- maple writer: `maple-py/src/maple/pdb/{writer,pager,rows,strings}.py`, model in
+  `maple-py/src/maple/model.py`.
+- Format truth (your inputs): `maple-py/src/kaitai/rekordbox_pdb.py` (layout/types)
+  and `maple-py/re/FORMAT_SPEC.md` (value-construction rules). Read both each run.
+- Reference real export: `maple-py/data/acemo/PIONEER/rekordbox/export.pdb`.
+- Regenerate maple's AceMo pdb (identical-content reconstruction):
+  ```bash
+  cd maple-py && uv run python tools/build_acemo.py   # -> captures/maple_acemo.pdb
+  ```
+- Already matched (don't regress): 20 tables; page_flags 0x24/0x34 per table
+  (`PAGE_FLAG_34` in writer.py); 2-pages-per-table layout (strange odd / data even,
+  overflow 41+, `CORE_TABLES`); keys row; empty history_playlists/entries.
+
+## Your loop, per finding
+1. Read the latest `FORMAT_SPEC.md` rule + any changed kaitai fields.
+2. Implement it in the writer (`rows.py` for row fields, `pager.py`/`writer.py`
+   for page/layout). Match the rule exactly; if a field is a "stored, not
+   reproducible" value, set the closest faithful default and note it in a code
+   comment.
+3. `uv run python tools/build_acemo.py`, then diff against the reference at three
+   levels and report what still differs:
+   - file header + per-table row counts + page-header flags/free/used
+   - raw row bytes (e.g. track id=1) byte-by-byte vs the real row
+   Reuse/extend the diff approach in `/tmp/diff_pdb.py` + `/tmp/rowdiff.py` (or
+   write equivalents). `uv run pytest -q` must still pass.
+4. Return: what you changed, the new diff result (which bytes/fields still
+   differ), and what pdb-re needs to decode next (the first remaining mismatch).
+
+Goal: ZERO diff between `captures/maple_acemo.pdb` and the reference. Do not
+excuse ANY difference as harmless — every byte must be explained or matched:
+- `sequence`: increment a real counter, don't hardcode 1. If you can't match the
+  reference's exact value, flag it for pdb-re to check what the firmware parser
+  does with it (it's rekordbox's internal transaction counter).
+- page layout / `next_unused` / overflow-page placement: match it. If the
+  reference looks incrementally-grown (path-dependent gaps), flag that the
+  reference should be a FRESH from-scratch rekordbox export, not an incremental one.
+- density / free / used: investigate, never assume harmless.
+Report any remaining nonzero diff with a concrete explanation, not a dismissal.