"""BSP 资产锚点检测脚本。

在 UE5 编辑器 Python 环境中运行，检测每个资产的 Bounds Origin，
判断锚点是中心、角落还是底部中心。

用法:
  方式1 — 命令行: python main.py check-pivots
  方式2 — 编辑器内: exec(open(r"check_pivots.py").read())
"""

import sys
import os
from pathlib import Path

# 将 level-builder 根目录加入 sys.path
_SCRIPT_DIR = Path(__file__).resolve().parent
_LB_DIR = _SCRIPT_DIR
if str(_LB_DIR) not in sys.path:
    sys.path.insert(0, str(_LB_DIR))

from config.asset_mapping import MESH_ASSETS

try:
    import unreal
    HAS_UNREAL = True
except ImportError:
    HAS_UNREAL = False


def check_pivots():
    """检测所有 BSP 资产的锚点类型。"""
    if not HAS_UNREAL:
        print("[错误] 需要在 UE5 编辑器 Python 环境中运行")
        return

    results = []
    for name, info in MESH_ASSETS.items():
        path = info["path"]
        default_size = info.get("default_size")
        mesh = unreal.load_asset(path)

        if not mesh:
            results.append(f"{name}: ⚠️ 无法加载")
            continue

        # 获取 Bounding Box (UE5 Box 对象有 min/max，没有 origin/extent)
        bb = mesh.get_bounding_box()
        bmin = bb.min
        bmax = bb.max

        mn_x, mn_y, mn_z = bmin.x, bmin.y, bmin.z
        mx_x, mx_y, mx_z = bmax.x, bmax.y, bmax.z
        size_x = mx_x - mn_x
        size_y = mx_y - mn_y
        size_z = mx_z - mn_z

        # 判断锚点类型:
        # CENTER:      min ≈ (-half, -half, -half)，对称包围盒
        # CORNER:      min ≈ (0, 0, 0)，锚点在角落
        # CENTER_BOTTOM: min ≈ (-half, -half, 0)，锚点在底部中心
        pivot_type = "UNKNOWN"
        offset_desc = ""

        if default_size:
            dw, dh, dd = default_size
            half_w, half_h, half_d = dw / 2, dh / 2, dd / 2
            tol = 5  # cm 容差

            is_corner = (abs(mn_x) < tol and abs(mn_y) < tol and abs(mn_z) < tol)
            is_center = (abs(mn_x + half_w) < tol and abs(mn_y + half_h) < tol
                         and abs(mn_z + half_d) < tol)
            is_center_bot = (abs(mn_x + half_w) < tol and abs(mn_y + half_h) < tol
                             and abs(mn_z) < tol)

            if is_corner:
                pivot_type = "CORNER"
            elif is_center:
                pivot_type = "CENTER"
            elif is_center_bot:
                pivot_type = "CENTER_BOTTOM"
            else:
                pivot_type = "OTHER"
                offset_desc = f" (min=({mn_x:.0f},{mn_y:.0f},{mn_z:.0f}), expected corner=0/center=-{half_w:.0f})"
        else:
            # 无 default_size，用 min 值推断
            tol = 5
            if abs(mn_x) < tol and abs(mn_y) < tol and abs(mn_z) < tol:
                pivot_type = "CORNER?"
            elif mn_z < -tol:
                pivot_type = "CENTER?"
            else:
                pivot_type = "CENTER_BOTTOM?"
            offset_desc = f" (no default_size, inferred)"

        results.append(
            f"{name}:\n"
            f"  min=({mn_x:.1f}, {mn_y:.1f}, {mn_z:.1f})  "
            f"max=({mx_x:.1f}, {mx_y:.1f}, {mx_z:.1f})  "
            f"size=({size_x:.0f}, {size_y:.0f}, {size_z:.0f})\n"
            f"  default_size={default_size}  →  pivot={pivot_type}{offset_desc}"
        )

    print("=" * 60)
    print("BSP 资产锚点检测结果")
    print("=" * 60)
    for r in results:
        print(r)
    print("=" * 60)

    # 保存结果
    out_path = Path(__file__).parent / "output" / "pivot_check.txt"
    out_path.parent.mkdir(exist_ok=True)
    with open(out_path, "w", encoding="utf-8") as f:
        f.write("BSP 资产锚点检测结果\n")
        f.write("=" * 60 + "\n")
        for r in results:
            f.write(r + "\n")
    print(f"\n结果已保存: {out_path}")


# 供命令行调用
if __name__ == "__main__":
    check_pivots()