PROCITY/pipeline/check_contract.py

#!/usr/bin/env python3
"""Assert the DJ-gear named-node contract survives normalization — read from the GLB, not Blender.

    python3 pipeline/check_contract.py SRC_DIR OUT_DIR MAP.json
    python3 pipeline/check_contract.py --list FILE.glb [FILE.glb ...]

The contract 90sDJsim's GEAR driver reads (dj-gear/README.md) is five bare node names:

    Platter_SPIN · Arm_YAW · Fader_PITCH · Fader_CROSS · Btn_STARTSTOP

Integrator ruling 5 exists because `gltf-transform optimize` silently deleted `Fader_CROSS` from a
696-node mixer. "Silently" is the operative word, so this check parses the **shipped GLB's** node
list rather than asking the tool that produced it — a scene-graph scan inside Blender still sees
control EMPTIES that were never exported, and would have reported a contract that the file does
not actually carry.

Verdict per model: PASS  = every contract node present in the source is present in the output.
                  FAIL  = one or more were lost (the ruling-5 failure mode).
                  N/A   = the source carried none (a cartridge has no crossfader).
Exit 1 if any FAIL.
"""
import json, os, struct, sys

CONTRACT = ["Platter_SPIN", "Arm_YAW", "Fader_PITCH", "Fader_CROSS", "Btn_STARTSTOP"]


def glb_nodes(path):
    """Node names from a GLB's JSON chunk. Dependency-free — no Blender, no pygltflib."""
    d = open(path, "rb").read()
    if d[:4] != b"glTF":
        raise ValueError("not a GLB")
    off = 12
    while off + 8 <= len(d):
        clen, ctype = struct.unpack("<II", d[off:off + 8])
        if ctype == 0x4E4F534A:
            g = json.loads(d[off + 8: off + 8 + clen].decode("utf-8"))
            return [n.get("name", "") for n in g.get("nodes", [])]
        off += 8 + clen
    raise ValueError("no JSON chunk")


def contract_of(path):
    names = set(glb_nodes(path))
    return [c for c in CONTRACT if c in names]


def main():
    if "--list" in sys.argv:
        for f in sys.argv[sys.argv.index("--list") + 1:]:
            print(f"{os.path.basename(f):46} {','.join(contract_of(f)) or '-'}")
        return 0
    if len(sys.argv) < 4:
        print(__doc__)
        return 2
    src_dir, out_dir, mapfile = sys.argv[1], sys.argv[2], sys.argv[3]
    pairs = json.load(open(mapfile))          # [{"src":"TTM54i.glb","file":"procity_...glb","mode":...}]

    rows, fails = [], 0
    for p in pairs:
        s = os.path.join(src_dir, p["src"])
        o = os.path.join(out_dir, p["file"])
        if not (os.path.isfile(s) and os.path.isfile(o)):
            rows.append({**p, "verdict": "MISSING"})
            fails += 1
            continue
        before, after = contract_of(s), contract_of(o)
        if not before:
            verdict = "N/A"
        elif p.get("mode") == "static":
            # a static dressing copy is one joined mesh BY DESIGN — it is not claimed to be
            # drivable, so a missing contract here is expected, not a failure.
            verdict = "STATIC (contract intentionally dropped)" if not after else "STATIC"
        elif set(before) <= set(after):
            verdict = "PASS"
        else:
            verdict = "FAIL"
            fails += 1
        rows.append({**p, "contract_before": before, "contract_after": after, "verdict": verdict})

    w = max(len(r["file"]) for r in rows) if rows else 40
    print(f"{'shipped file':{w}} {'mode':7} {'source contract':46} {'shipped contract':46} verdict")
    print("-" * (w + 110))
    for r in rows:
        print(f"{r['file']:{w}} {r.get('mode',''):7} "
              f"{','.join(r.get('contract_before', [])) or '-':46} "
              f"{','.join(r.get('contract_after', [])) or '-':46} {r['verdict']}")
    n_pass = sum(1 for r in rows if r["verdict"] == "PASS")
    n_na = sum(1 for r in rows if r["verdict"] == "N/A")
    n_st = sum(1 for r in rows if str(r["verdict"]).startswith("STATIC"))
    print(f"\nPASS {n_pass} · STATIC {n_st} · N/A {n_na} · FAIL {fails}")
    json.dump(rows, open(os.path.join(out_dir, "_contract_check.json"), "w"), indent=2)
    return 1 if fails else 0


if __name__ == "__main__":
    sys.exit(main())