"""Check the vat: separate parts against each other, topology. Nothing is saved.

    blender.exe -b ../NutritionVat.blend --python nv_check.py      -> build/check_report.json

Triangle overlap in world space (BVH) between every pair of separate meshes: the body, the liquid, the two canisters
and the three pipes (each a fitting, a run and a ceiling coupling). The parts of one pipe meet by design (the bands
clamp the film, the film slides over the spigot): those pairs are listed, not counted. Smallest gaps from the liquid to
the glass, from the canisters and the pipes to the body. Topology of each mesh.
"""
import bpy, bmesh, json, os, math
from mathutils.bvhtree import BVHTree

HERE = os.path.dirname(os.path.abspath(__file__))
exec(open(os.path.join(HERE, "nv_lib.py")).read())


def world_bm(ob):
    bm = bmesh.new()
    bm.from_mesh(ob.data)
    bm.transform(ob.matrix_world)
    return bm


def tree(ob):
    bm = world_bm(ob)
    t = BVHTree.FromBMesh(bm)
    vs = [v.co.copy() for v in bm.verts]
    bm.free()
    return t, vs


def gap(verts, t):
    best = 1e9
    for v in verts:
        hit = t.find_nearest(v)
        if hit[0] is not None:
            best = min(best, hit[3])
    return best


def main():
    bpy.context.view_layer.update()
    names = ["SM_NutritionVat_Body", "SM_NutritionVat_Fluid", "NutritionVat_Canister_R", "NutritionVat_Canister_L"]
    names += sorted(o.name for o in bpy.data.objects if o.name.startswith("NutritionVat_Pipe"))
    obs = {n: bpy.data.objects[n] for n in names}
    T = {n: tree(o) for n, o in obs.items()}
    rep = {"overlaps": {}, "same_pipe_contacts": {}, "gaps_mm": {}, "audit": {}}
    pipe_of = lambda n: n.rsplit("_", 1)[1] if n.startswith("NutritionVat_Pipe") else None
    for i in range(len(names)):
        for j in range(i + 1, len(names)):
            a, b = names[i], names[j]
            n = len(T[a][0].overlap(T[b][0]))
            if pipe_of(a) and pipe_of(a) == pipe_of(b):
                rep["same_pipe_contacts"]["%s x %s" % (a, b)] = n
            else:
                rep["overlaps"]["%s x %s" % (a, b)] = n
    body = T["SM_NutritionVat_Body"][0]
    rep["gaps_mm"]["liquid to body (glass)"] = round(gap(T["SM_NutritionVat_Fluid"][1], body) * 1000, 2)
    for c in names[2:]:
        rep["gaps_mm"][c + " to body"] = round(gap(T[c][1], body) * 1000, 2)
    for n, o in obs.items():
        if n.startswith("NutritionVat_Pipe") and not n.endswith("_A"):
            continue                                   # the three pipes share their meshes
        rep["audit"][n] = audit(o)
    clash = sum(v for v in rep["overlaps"].values())
    rep["clash_pairs_total"] = clash
    with open(os.path.join(HERE, "check_report.json"), "w") as fh:
        json.dump(rep, fh, indent=1)
    print("CHECK OK" if not clash else "CHECK CLASH", json.dumps({k: v for k, v in rep["overlaps"].items() if v}),
          json.dumps(rep["gaps_mm"]))


main()