"""Builds the machine parts kit into the open Blender file (run through the Blender MCP: exec this file).

build(keys=None) makes every item of mpk_items.ITEMS (or the given keys), replacing an item's objects if they exist.
Objects: SM_MPK_<key>_<Name> (static, origin at its centre on the floor) and SM_MPK_<key>_<Name>_<Part> for moving
parts (child of the item, origin on its axis, rotation 0, scale 1). Laid out as on the user's sheet.
"""
import importlib, math, os, sys
import bpy

HERE = os.path.dirname(os.path.abspath(__file__)) if "__file__" in dir() else BUILD_DIR
if HERE not in sys.path:
    sys.path.insert(0, HERE)
import mpk_lib, mpk_items
importlib.reload(mpk_lib); importlib.reload(mpk_items)
from mpk_lib import U, audit

COLL = "MPK | Parts"
MATS = ("MPK_Paint", "MPK_Dark", "MPK_Steel")


def coll(name, parent=None):
    c = bpy.data.collections.get(name) or bpy.data.collections.new(name)
    p = parent or bpy.context.scene.collection
    if c.name not in p.children:
        p.children.link(c)
    return c


def mat(name):
    mt = bpy.data.materials.get(name)
    if mt is None:
        mt = bpy.data.materials.new(name)
        mt.diffuse_color = {"MPK_Paint": (0.42, 0.36, 0.28, 1), "MPK_Dark": (0.05, 0.05, 0.05, 1),
                            "MPK_Steel": (0.3, 0.3, 0.3, 1)}[name]
    return mt


def make_obj(name, bm, c, loc, parent=None):
    old = bpy.data.objects.get(name)
    if old is not None:
        me_old = old.data
        bpy.data.objects.remove(old)
        if me_old.users == 0:
            bpy.data.meshes.remove(me_old)
    me = bpy.data.meshes.new(name)
    bm.to_mesh(me)
    bm.free()
    for n in MATS:
        me.materials.append(mat(n))
    me.shade_smooth()
    me.set_sharp_from_angle(angle=math.radians(40))
    ob = bpy.data.objects.new(name, me)
    c.objects.link(ob)
    if parent is not None:
        ob.parent = parent
        ob.matrix_parent_inverse.identity()
    ob.location = loc
    return ob


def build(keys=None):
    c = coll(COLL)
    report = {}
    for key, name, (cx, cy), fn in mpk_items.ITEMS:
        if keys and key not in keys:
            continue
        # children first, so a rebuild leaves no orphans
        for ob in [o for o in bpy.data.objects if o.name.startswith(f"SM_MPK_{key}_")]:
            me = ob.data
            bpy.data.objects.remove(ob)
            if me and me.users == 0:
                bpy.data.meshes.remove(me)
        k = mpk_lib.Kit()
        moving = fn(k) or []
        ob = make_obj(f"SM_MPK_{key}_{name}", k.finish(), c, ((cx - 1000) * U, -(cy - 470) * U, 0.0))
        ob["mpk_key"] = key
        ob["mpk_collision"] = [list(b[0]) + list(b[1]) for b in k.boxes]
        r = {"main": dict(audit(ob.data), culled=k.culled)}
        for suf, kk, piv, axis in moving:
            ch = make_obj(f"SM_MPK_{key}_{name}_{suf}", kk.finish(floor=False), c, tuple(v * U for v in piv), ob)
            ch["mpk_axis"] = axis
            r[suf] = dict(audit(ch.data), culled=kk.culled)
        report[key] = r
    return report