"""
ZF LIFETEC 自适应约束系统逻辑

传统约束系统：
- 碰撞传感器 → 固定力曲线 → 气囊+安全带

ZF LIFETEC 集成系统：
- 座舱感知（乘员分类+姿态+体型） → 自适应力曲线 → 变容气囊+电机安全带
"""

from dataclasses import dataclass
from typing import Optional
from enum import IntEnum


class OccupantClass(IntEnum):
    SMALL_ADULT = 0     # 小体型成人
    AVERAGE_ADULT = 1   # 中等体型成人
    LARGE_ADULT = 2     # 大体型成人
    CHILD = 3           # 儿童（含儿童座椅）
    EMPTY = 4           # 空座


class PostureState(IntEnum):
    NORMAL = 0          # 正常坐姿
    RECLINED = 1        # 后仰
    LEANING_FORWARD = 2  # 前倾
    OUT_OF_POSITION = 3  # OOP 异常姿态


@dataclass
class OccupantInfo:
    """乘员信息（来自座舱感知）"""
    classification: OccupantClass = OccupantClass.EMPTY
    weight: float = 0.0  # kg
    stature: float = 0.0  # cm
    posture: PostureState = PostureState.NORMAL
    seat_distance_to_dashboard: float = 0.0  # cm
    belt_locked: bool = False
    belt_position_correct: bool = True


class AdaptiveRestraintController:
    """
    ZF LIFETEC 自适应约束控制器
    
    根据乘员信息动态调整约束系统参数
    """
    
    def __init__(self):
        # Dual Contour Airbag 参数
        self.airbag_volumes = {
            OccupantClass.SMALL_ADULT: 60,    # 升
            OccupantClass.AVERAGE_ADULT: 75,  # 升
            OccupantClass.LARGE_ADULT: 90,    # 升
            OccupantClass.CHILD: 0,           # 禁用
            OccupantClass.EMPTY: 0,          # 禁用
        }
        
        # ACR.8 安全带预紧力参数
        self.belt_pretension = {
            OccupantClass.SMALL_ADULT: 150,   # N
            OccupantClass.AVERAGE_ADULT: 250,  # N
            OccupantClass.LARGE_ADULT: 350,   # N
            OccupantClass.CHILD: 100,         # N
            OccupantClass.EMPTY: 0,
        }
        
        # 负载限制
        self.load_limit = {
            OccupantClass.SMALL_ADULT: 2500,   # N
            OccupantClass.AVERAGE_ADULT: 3500,  # N
            OccupantClass.LARGE_ADULT: 4500,   # N
            OccupantClass.CHILD: 1500,          # N
            OccupantClass.EMPTY: 0,
        }
    
    def compute_restraint_profile(self, 
                                   occupant: OccupantInfo,
                                   crash_severity: float) -> dict:
        """
        计算约束系统参数
        
        Args:
            occupant: 乘员信息
            crash_severity: 碰撞严重程度 (0-1)
            
        Returns:
            profile: 约束系统参数
        """
        # OOP 检测：如果乘员前倾且距离仪表板过近
        if (occupant.posture == PostureState.OUT_OF_POSITION and
            occupant.seat_distance_to_dashboard < 30):
            # 降低气囊力度或禁用
            airbag_volume = 0  # OOP 时禁用气囊
            belt_pretension = self.belt_pretension[occupant.classification] * 1.5
            load_limit = self.load_limit[occupant.classification] * 0.7
            warning = "OOP: 气囊禁用, 安全带增强"
        elif (occupant.posture == PostureState.RECLINED and
              occupant.seat_distance_to_dashboard > 50):
            # 后仰坐姿：增大气囊容积
            base_vol = self.airbag_volumes[occupant.classification]
            airbag_volume = min(base_vol * 1.2, 90)
            belt_pretension = self.belt_pretension[occupant.classification]
            load_limit = self.load_limit[occupant.classification]
            warning = "后仰: 气囊增大"
        else:
            airbag_volume = self.airbag_volumes[occupant.classification]
            belt_pretension = self.belt_pretension[occupant.classification]
            load_limit = self.load_limit[occupant.classification]
            warning = "正常"
        
        # 安全带误用检测
        if not occupant.belt_locked:
            belt_active = False
            warning += " | 安全带未扣"
        elif not occupant.belt_position_correct:
            belt_active = True
            warning += " | 安全带位置异常"
        else:
            belt_active = True
        
        return {
            'airbag_volume_liters': airbag_volume,
            'airbag_active': airbag_volume > 0,
            'belt_pretension_N': belt_pretension,
            'belt_load_limit_N': load_limit,
            'belt_active': belt_active,
            'warning': warning
        }


# ========== 测试 ==========

if __name__ == "__main__":
    controller = AdaptiveRestraintController()
    
    # 场景1: 正常坐姿成人
    adult1 = OccupantInfo(
        classification=OccupantClass.AVERAGE_ADULT,
        weight=75, stature=175,
        posture=PostureState.NORMAL,
        seat_distance_to_dashboard=45,
        belt_locked=True, belt_position_correct=True
    )
    r1 = controller.compute_restraint_profile(adult1, 0.8)
    print(f"场景1 - 正常成人:")
    print(f"  气囊: {r1['airbag_volume_liters']}L ({'激活' if r1['airbag_active'] else '禁用'})")
    print(f"  安全带预紧: {r1['belt_pretension_N']}N")
    print(f"  负载限制: {r1['belt_load_limit_N']}N")
    print(f"  {r1['warning']}")
    
    # 场景2: OOP 前倾
    oop1 = OccupantInfo(
        classification=OccupantClass.SMALL_ADULT,
        weight=50, stature=160,
        posture=PostureState.OUT_OF_POSITION,
        seat_distance_to_dashboard=25,
        belt_locked=True, belt_position_correct=True
    )
    r2 = controller.compute_restraint_profile(oop1, 0.8)
    print(f"\n场景2 - OOP前倾:")
    print(f"  气囊: {r2['airbag_volume_liters']}L ({'激活' if r2['airbag_active'] else '禁用'})")
    print(f"  安全带预紧: {r2['belt_pretension_N']}N")
    print(f"  {r2['warning']}")
    
    # 场景3: 后仰
    reclined = OccupantInfo(
        classification=OccupantClass.LARGE_ADULT,
        weight=90, stature=185,
        posture=PostureState.RECLINED,
        seat_distance_to_dashboard=55,
        belt_locked=True, belt_position_correct=True
    )
    r3 = controller.compute_restraint_profile(reclined, 0.9)
    print(f"\n场景3 - 后仰:")
    print(f"  气囊: {r3['airbag_volume_liters']}L ({'激活' if r3['airbag_active'] else '禁用'})")
    print(f"  {r3['warning']}")