"""Check the feeder: drivers, the moving parts through their whole travel, topology. Nothing is saved.

    blender.exe -b ../NutritionFeeder.blend --python nf_check.py      -> build/check_report.json

Runs NutritionFeeder_Root["inject"] from 0 to 1 in 101 steps and tests the nozzle and the needle against the body and
against each other (triangle overlap in world space, BVH), and measures their smallest clearance to the body's bore.
"""
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, "nf_lib.py")).read())


def bvh(ob, dg):
    ev = ob.evaluated_get(dg)
    me = ev.to_mesh()
    bm = bmesh.new()
    bm.from_mesh(me)
    bm.transform(ev.matrix_world)
    t = BVHTree.FromBMesh(bm)
    verts = [v.co.copy() for v in bm.verts]
    bm.free()
    ev.to_mesh_clear()
    return t, verts


def main():
    sc = bpy.context.scene
    root = bpy.data.objects["NutritionFeeder_Root"]
    body = bpy.data.objects["SM_NutritionFeeder_Body"]
    nozzle = bpy.data.objects["SM_NutritionFeeder_Nozzle"]
    needle = bpy.data.objects["SM_NutritionFeeder_Needle"]
    rep = {"drivers": {}, "travel": {}, "clashes": [], "audit": {}}
    for ob in (nozzle, needle):
        for fc in ob.animation_data.drivers:
            d = fc.driver
            rep["drivers"][ob.name] = dict(path=fc.data_path, index=fc.array_index, valid=d.is_valid,
                                           simple=d.is_simple_expression, expression=d.expression)
    if root.animation_data:
        root.animation_data.action = None
    dg = bpy.context.evaluated_depsgraph_get()
    tb, _ = bvh(body, dg)
    min_gap = {nozzle.name: 1e9, needle.name: 1e9}
    for k in range(101):
        root["inject"] = k / 100.0
        root.update_tag()                         # a property set from Python is not tagged by itself
        sc.frame_set(1 + (k % 2))
        dg = bpy.context.evaluated_depsgraph_get()
        dg.update()
        tn, vn = bvh(nozzle, dg)
        td, vd = bvh(needle, dg)
        for name, t in ((nozzle.name, tn), (needle.name, td)):
            n = len(t.overlap(tb))
            if n:
                rep["clashes"].append(dict(inject=k / 100.0, part=name, against=body.name, pairs=n))
        n = len(tn.overlap(td))
        if n:
            rep["clashes"].append(dict(inject=k / 100.0, part=nozzle.name, against=needle.name, pairs=n))
        for name, verts in ((nozzle.name, vn), (needle.name, vd)):
            for v in verts[::3]:
                hit = tb.find_nearest(v)
                if hit[0] is not None:
                    min_gap[name] = min(min_gap[name], hit[3])
        if k in (0, 55, 100):
            ev = lambda o: o.evaluated_get(dg).matrix_world.translation
            rep["travel"]["inject %.2f" % (k / 100)] = {o.name: [round(c, 5) for c in ev(o)] for o in (nozzle, needle)}
    rep["smallest_gap_to_body_mm"] = {k: round(v * 1000, 2) for k, v in min_gap.items()}
    for ob in (body, nozzle, needle):
        rep["audit"][ob.name] = audit(ob)
    with open(os.path.join(HERE, "check_report.json"), "w") as fh:
        json.dump(rep, fh, indent=1)
    print("CHECK OK" if not rep["clashes"] else "CHECK CLASH", json.dumps(rep))


main()