# SPDX-License-Identifier: MIT OR GPL-3.0-or-later
from dataclasses import dataclass
from typing import TYPE_CHECKING, Optional

if TYPE_CHECKING:
    from bpy.types import Mesh, Object


@dataclass
class MaterialInfo:
    """材质信息数据类"""
    name: str
    index: int
    face_count: int
    is_skin: bool


def find_body_mesh(armature: "Object") -> Optional["Object"]:
    """
    在Armature的子对象中查找名为"Body"的网格对象

    Args:
        armature: Armature对象

    Returns:
        Body网格对象，如果不存在则返回None
    """
    if armature is None:
        return None

    for child in armature.children:
        if child.type == "MESH" and child.name == "Body":
            return child

    return None


def is_skin_material(material_name: str) -> bool:
    """
    判断材质是否为皮肤材质

    Args:
        material_name: 材质名称

    Returns:
        如果材质名包含"SKIN"则返回True（不区分大小写）
    """
    return "SKIN" in material_name.upper()


def get_material_face_count(mesh: "Mesh", material_index: int) -> int:
    """
    获取指定材质的面数量

    Args:
        mesh: 网格数据
        material_index: 材质索引

    Returns:
        使用该材质的面数量
    """
    count = 0
    for polygon in mesh.polygons:
        if polygon.material_index == material_index:
            count += 1
    return count


def generate_unique_name(base_name: str, existing_names: set[str]) -> str:
    """
    生成唯一的对象名称

    Args:
        base_name: 基础名称
        existing_names: 已存在的名称集合

    Returns:
        唯一的名称
    """
    if base_name not in existing_names:
        return base_name

    suffix = 1
    while True:
        candidate = f"{base_name}.{suffix:03d}"
        if candidate not in existing_names:
            return candidate
        suffix += 1