"""
models.py
数据模型模块：使用 Pydantic 定义请求/响应的数据结构。
FastAPI 会自动用这些模型做参数校验和文档生成。
"""

from pydantic import BaseModel, Field
from typing import Optional, List
from datetime import datetime


# ═══════════════════════════════════════════════════════════════
# 请求模型（客户端传入）
# ═══════════════════════════════════════════════════════════════

class DeviceCheckRequest(BaseModel):
    """设备校验请求：APP 启动时携带 SN 进行合法性校验"""
    sn: str = Field(..., min_length=5, description="设备序列号，如 GD30-20260507-001")


class LicenseGenerateRequest(BaseModel):
    """生成授权文件请求：管理后台为某台设备创建授权"""
    sn: str = Field(..., description="目标设备 SN")
    modules: List[str] = Field(default=[], description="激活的模块列表，如 ['1D', '2D']")
    valid_days: int = Field(default=365, ge=1, le=3650, description="授权有效期（天），默认一年")


class ActivateReportRequest(BaseModel):
    """上报激活状态请求：设备主机首次联网后回传激活结果"""
    sn: str = Field(..., description="设备序列号")
    status: str = Field(..., pattern="^(已激活|激活失败)$", description="上报状态：已激活 或 激活失败")


# ═══════════════════════════════════════════════════════════════
# 响应模型（服务端返回）
# ═══════════════════════════════════════════════════════════════

class DeviceInfo(BaseModel):
    """设备信息响应"""
    sn: str
    status: str
    activated_at: Optional[str] = None
    created_at: str


class CheckResponse(BaseModel):
    """设备校验响应：告诉 APP 这台设备是否合法、是否已激活"""
    valid: bool = Field(..., description="SN 是否存在于平台")
    activated: bool = Field(..., description="是否已激活")
    message: str = Field(..., description="给 APP 的提示信息")


class LicenseData(BaseModel):
    """授权文件内的业务数据结构（未加密前）"""
    version: str = Field(default="1.0", description="授权文件版本")
    device_sn: str = Field(..., description="绑定的设备 SN")
    generated_at: str = Field(..., description="生成时间 ISO8601")
    valid_until: str = Field(..., description="有效期截止时间")
    modules: List[str] = Field(default=[], description="授权模块列表")
    status: str = Field(default="active", description="授权状态")


class LicenseResponse(BaseModel):
    """生成授权文件响应：返回加密后的授权文件字符串"""
    success: bool
    encrypted_license: Optional[str] = Field(None, description="Base64 编码的加密授权文件")
    raw_license: Optional[dict] = Field(None, description="明文授权文件（仅调试用，生产环境可去掉）")
    message: str


class ActivateResponse(BaseModel):
    """上报激活状态响应"""
    success: bool
    sn: str
    new_status: str
    activated_at: Optional[str] = None
    message: str