# -*- coding: utf-8 -*-
"""Opens OrePatches.blend read-only and checks how the clusters sit: does every cluster reach into the rock all
round its foot, and do two clusters of one patch run into each other.

  blender -b ../OrePatches.blend --python check_fit.py
"""
import bpy, bmesh, os, json, math
import numpy as np
from mathutils import Vector
from mathutils.bvhtree import BVHTree

HERE = os.path.dirname(os.path.abspath(__file__))
dg = bpy.context.evaluated_depsgraph_get()
out = {}


def tree(ob):
    bm = bmesh.new()
    bm.from_mesh(ob.data)
    bm.transform(ob.matrix_world)
    t = BVHTree.FromBMesh(bm)
    V = np.array([v.co[:] for v in bm.verts])
    bm.free()
    return t, V


for root in [o for o in bpy.data.objects if o.type == 'EMPTY' and o.name.startswith('OrePatch_')]:
    rock = next(c for c in root.children if c.name.startswith('SM_OreRock_'))
    insts = sorted([c for c in root.children if '_Ore_' in c.name], key=lambda o: o.name)
    rt, _ = tree(rock)
    trees = [tree(o) for o in insts]
    floating, crossing = [], []
    for ob, (t, V) in zip(insts, trees):
        mw = ob.matrix_world
        z = (mw.to_3x3() @ Vector((0, 0, 1))).normalized()
        s = mw.to_scale()[0]
        # 12 points round the foot, at 70 % of the footprint: the rock must reach the cluster's base plane there
        worst = 1e9
        for k in range(12):
            a = k * math.pi / 6
            p = mw @ Vector((0.175 * math.cos(a), 0.175 * math.sin(a), 0.0))
            hit = rt.ray_cast(p + z * (0.5 + 0.25 * s), -z)
            if hit[0] is None:
                worst = min(worst, -9.0)
                continue
            worst = min(worst, ((hit[0] - p).dot(z)) / s)
        if worst < -0.002:
            floating.append((ob.name, round(worst * s, 3)))
    for i in range(len(insts)):
        for j in range(i + 1, len(insts)):
            n = len(trees[i][0].overlap(trees[j][0]))
            if n:
                crossing.append((insts[i].name.split('_Ore_')[1], insts[j].name.split('_Ore_')[1], n))
    out[root.name] = dict(clusters=len(insts), foot_above_rock=floating, crossing_pairs=crossing)
    print('[fit]', root.name, 'clusters', len(insts), '| foot not buried:', floating or 'none', '| crossing pairs:', crossing or 'none')
json.dump(out, open(os.path.join(HERE, 'fit_report.json'), 'w'), indent=1)