"""Door robot arm: the obstacles round the arms, as surface points for the fit (2026-10-18, scale-up).

Reads a .blend (the ship, read only, or this model's file) and samples the surfaces of everything the depsgraph shows
(collection instances and linked library objects included) inside the pockets' and the moon pool's box under the deck
top, except: this model's own parts ('DoorArm...', the installed arms and their rail system), the user's old rail boxes
and carriage placeholders (hidden in the ship), and the two moon pool doors (the fit moves them with their animation).
Writes build/obstacles_<tag>.npz: points (float32, metres, ship coordinates), their object index, the object names.

    blender -b --factory-startup --python build/dra_obstacles.py -- <file.blend> <tag> [scene name]
"""
import os
import sys
import math
import random
import numpy as np
import bpy
from mathutils import Vector

HERE = os.path.dirname(os.path.abspath(__file__))
args = sys.argv[sys.argv.index("--") + 1:]
path, tag = args[0], args[1]
bpy.ops.wm.open_mainfile(filepath=path, load_ui=False)
if len(args) > 2:
    sc = bpy.data.scenes[args[2]]
    if bpy.context.window_manager.windows:
        bpy.context.window_manager.windows[0].scene = sc
sc = bpy.context.scene
sc.frame_set(1)
dg = bpy.context.evaluated_depsgraph_get()
REG = ((-10.2, 16.2), (-9.7, 2.2), (-11.2, -3.30))
STEP = 0.04
SKIP = ("DoorArm", "Moonpool_Door_Aft", "Moonpool_Door_Fore", "upper rail", "rail carriage")
rng = random.Random(3)
pts, ids, names = [], [], []
for inst in dg.object_instances:
    ob = inst.object
    if ob.type not in ('MESH', 'CURVE', 'SURFACE', 'FONT', 'META'):
        continue
    nm = ob.name
    if any(s in nm for s in SKIP):
        continue
    M = inst.matrix_world.copy()
    bb = [M @ Vector(c) for c in ob.bound_box]
    if any(max(p[i] for p in bb) < REG[i][0] or min(p[i] for p in bb) > REG[i][1] for i in range(3)):
        continue
    try:
        me = ob.to_mesh()
    except Exception:
        continue
    if me is None:
        continue
    me.calc_loop_triangles()
    V = [M @ v.co for v in me.vertices]
    k = len(names)
    names.append(nm + ((" <" + inst.instance_object.name + ">") if inst.is_instance and inst.instance_object else ""))
    n0 = len(pts)
    for lt in me.loop_triangles:
        a, b, c = (V[i] for i in lt.vertices)
        lo = [min(a[i], b[i], c[i]) for i in range(3)]
        hi = [max(a[i], b[i], c[i]) for i in range(3)]
        if any(hi[i] < REG[i][0] or lo[i] > REG[i][1] for i in range(3)):
            continue
        area = (b - a).cross(c - a).length / 2
        n = max(1, int(math.ceil(area / (STEP * STEP))))
        for v in (a, b, c):
            pts.append((v.x, v.y, v.z))
            ids.append(k)
        for _ in range(n):
            r1, r2 = rng.random(), rng.random()
            if r1 + r2 > 1:
                r1, r2 = 1 - r1, 1 - r2
            p = a + (b - a) * r1 + (c - a) * r2
            pts.append((p.x, p.y, p.z))
            ids.append(k)
    ob.to_mesh_clear()
    print("[ob] %-60s %d points" % (names[-1][:60], len(pts) - n0), flush=True)
P = np.array(pts, np.float32)
m = (P[:, 0] >= REG[0][0]) & (P[:, 0] <= REG[0][1]) & (P[:, 1] >= REG[1][0]) & (P[:, 1] <= REG[1][1]) & \
    (P[:, 2] >= REG[2][0]) & (P[:, 2] <= REG[2][1])
np.savez_compressed(os.path.join(HERE, "obstacles_%s.npz" % tag), points=P[m], ids=np.array(ids, np.int32)[m],
                    names=np.array(names))
print("[ob] written", int(m.sum()), "points of", len(names), "objects", flush=True)