# services/material_service.py
"""材料属性管理服务 - 全局唯一材料属性源

所有材料属性（密度、收缩率、最小壁厚、泡沫特性等）集中在此，
geometry_analyzer / mold_generator / aluminum_foam_mold 等模块一律通过 MaterialService 查询，
禁止再各自维护材料字典，避免数据漂移。

历史问题：材料字典曾在 4 处重复定义且冲突（如 PE 收缩率此处 0.020 vs aluminum_foam_mold 0.025；
PC/PA/PMMA 收缩率、POM 密度也冲突；PS 在其他字典有而此处缺失）。现已统一，以本文件为唯一源。
泡沫材料原用 `shrinkage_rate` 键，现统一为 `shrinkage`（值一致）。
"""

from typing import Dict, Any, List


MATERIAL_PROPERTIES: Dict[str, Dict[str, Any]] = {
    # —— 注塑塑料 ——
    "ABS": {"name": "ABS", "density": 1.05, "shrinkage": 0.005, "is_foam": False, "min_wall": 1.2},
    "PP": {"name": "PP", "density": 0.90, "shrinkage": 0.016, "is_foam": False, "min_wall": 1.0},
    "PE": {"name": "PE", "density": 0.95, "shrinkage": 0.020, "is_foam": False, "min_wall": 1.0},
    "PC": {"name": "PC", "density": 1.20, "shrinkage": 0.007, "is_foam": False, "min_wall": 1.5},
    "PA": {"name": "PA", "density": 1.14, "shrinkage": 0.010, "is_foam": False, "min_wall": 1.0},
    "POM": {"name": "POM", "density": 1.41, "shrinkage": 0.020, "is_foam": False, "min_wall": 1.0},
    "PMMA": {"name": "PMMA", "density": 1.18, "shrinkage": 0.005, "is_foam": False, "min_wall": 1.5},
    "PBT": {"name": "PBT", "density": 1.31, "shrinkage": 0.015, "is_foam": False, "min_wall": 1.2},
    "PS": {"name": "PS", "density": 1.05, "shrinkage": 0.004, "is_foam": False, "min_wall": 1.0},
    # —— 铝泡沫 ——
    "AlSi10Mg": {"name": "AlSi10Mg", "density": 0.45, "shrinkage": 0.015, "is_foam": True,
                 "expansion_ratio": 2.5, "molding_temp": 380, "description": "常用铝硅泡沫"},
    "AlSi12": {"name": "AlSi12", "density": 0.50, "shrinkage": 0.012, "is_foam": True,
               "expansion_ratio": 2.2, "molding_temp": 360, "description": "高强度铝泡沫"},
    "Pure Al Foam": {"name": "Pure Al Foam", "density": 0.35, "shrinkage": 0.020, "is_foam": True,
                     "expansion_ratio": 3.0, "molding_temp": 400, "description": "纯铝泡沫"},
    "AlSi7Mg": {"name": "AlSi7Mg", "density": 0.40, "shrinkage": 0.018, "is_foam": True,
                "expansion_ratio": 2.8, "molding_temp": 390, "description": "轻质铝镁泡沫"},
}

# 默认回退材料
_DEFAULT_MATERIAL = MATERIAL_PROPERTIES["ABS"]


class MaterialService:
    """材料属性管理服务 - 集中管理材料字典，便于扩展和单测"""

    @staticmethod
    def get_material(material_name: str) -> Dict[str, Any]:
        """获取材料属性，不存在则回退到 ABS"""
        return MATERIAL_PROPERTIES.get(material_name, _DEFAULT_MATERIAL)

    @staticmethod
    def has_material(material_name: str) -> bool:
        """材料是否在字典中（不回退）"""
        return material_name in MATERIAL_PROPERTIES

    @staticmethod
    def is_foam_material(material_name: str) -> bool:
        return MATERIAL_PROPERTIES.get(material_name, _DEFAULT_MATERIAL).get("is_foam", False)

    @staticmethod
    def list_all_materials() -> List[str]:
        return list(MATERIAL_PROPERTIES.keys())

    @staticmethod
    def resolve_material(requested: str) -> str:
        """解析请求的材料名，若不在字典中则回退为 ABS"""
        return requested if requested in MATERIAL_PROPERTIES else "ABS"