#!/usr/bin/env python3
import hashlib
import json
import os
import pathlib
import sys
import tempfile

import bpy


def rounded(values):
    return [round(float(value), 6) for value in values]


def lattice_report():
    lattice = bpy.data.lattices.get("WebGapLattice")
    if lattice is None:
        raise RuntimeError("WebGapLattice is missing")
    return {
        "id": "lattice:WebGapLattice",
        "name": lattice.name,
        "dimensions": [lattice.points_u, lattice.points_v, lattice.points_w],
        "pointCount": len(lattice.points),
        "interpolation": [
            lattice.interpolation_type_u,
            lattice.interpolation_type_v,
            lattice.interpolation_type_w,
        ],
        "useOutside": bool(lattice.use_outside),
        "activePoint": -1,
        "vertexGroup": lattice.vertex_group,
        "points": [
            {
                "coDeform": rounded(point.co_deform),
                "weight": round(float(point.weight_softbody), 6),
                "selected": bool(point.select),
            }
            for point in lattice.points
        ],
    }


def main() -> None:
    arguments = sys.argv[sys.argv.index("--") + 1 :]
    if len(arguments) != 2:
        raise SystemExit("usage: blender -b --python check-lattice-desktop.py -- FIXTURE REPORT")
    fixture, output = (pathlib.Path(value).resolve() for value in arguments)
    bpy.ops.wm.open_mainfile(filepath=str(fixture), load_ui=False)
    before = lattice_report()
    descriptor, temporary = tempfile.mkstemp(prefix="m16-lattice-reopen-", suffix=".blend")
    os.close(descriptor)
    try:
        bpy.ops.wm.save_as_mainfile(filepath=temporary, check_existing=False, compress=True)
        bpy.ops.wm.open_mainfile(filepath=temporary, load_ui=False)
        after = lattice_report()
    finally:
        pathlib.Path(temporary).unlink(missing_ok=True)
    if before != after:
        raise RuntimeError(f"lattice save/reopen drift: {before} != {after}")
    report = {
        "schemaVersion": 1,
        "task": "M16-GAP-00010",
        "operation": "LATTICE_DATABLOCK_DESKTOP",
        "fixture": str(fixture),
        "fixtureSha256": hashlib.sha256(fixture.read_bytes()).hexdigest(),
        "lattice": after,
        "saveReopen": "EXACT",
        "blenderVersion": bpy.app.version_string,
    }
    output.parent.mkdir(parents=True, exist_ok=True)
    output.write_text(json.dumps(report, indent=2, sort_keys=True) + "\n", encoding="utf-8")
    print(f"lattice-desktop-ok points={after['pointCount']} saveReopen=exact")


if __name__ == "__main__":
    main()