from datetime import datetime, timezone

from fastapi import APIRouter, Depends, HTTPException

from app.middleware.auth import get_current_user
from app.models.checkup import CheckupPlan, CheckupItem
from app.models.user import User

router = APIRouter()

# 标准产检计划
STANDARD_CHECKUPS = [
    CheckupItem(title="首次产检", week=6, items=["B超确认宫内孕", "血常规", "尿常规", "肝功能", "肾功能"], preparations=["空腹", "带身份证和医保卡"], notes="确认怀孕和预产期", importance="high"),
    CheckupItem(title="NT检查", week=12, items=["NT超声筛查", "血清学筛查", "血压", "体重"], preparations=["不需要空腹", "需憋尿"], notes="筛查唐氏综合征风险", importance="high"),
    CheckupItem(title="唐氏筛查", week=16, items=["唐氏筛查抽血", "血压", "体重", "宫高腹围"], preparations=["空腹抽血"], notes="评估胎儿染色体异常风险", importance="high"),
    CheckupItem(title="大排畸检查", week=22, items=["四维彩超", "血压", "体重", "宫高腹围"], preparations=["不需要空腹", "提前预约"], notes="全面筛查胎儿结构畸形", importance="high"),
    CheckupItem(title="糖耐量检查", week=24, items=["OGTT糖耐量试验", "血压", "体重"], preparations=["空腹8-14小时", "检查前3天正常饮食"], notes="筛查妊娠期糖尿病", importance="high"),
    CheckupItem(title="常规产检", week=28, items=["血常规", "尿常规", "血压", "体重", "胎心监护"], preparations=["空腹"], notes="进入孕晚期，增加产检频率", importance="medium"),
    CheckupItem(title="常规产检", week=30, items=["B超评估胎儿发育", "血压", "体重", "胎心监护"], preparations=[], notes="评估胎儿生长发育", importance="medium"),
    CheckupItem(title="常规产检", week=32, items=["血常规", "尿常规", "血压", "体重", "胎心监护", "B超"], preparations=["空腹"], notes="观察胎位", importance="medium"),
    CheckupItem(title="GBS筛查", week=36, items=["B族链球菌筛查", "血压", "体重", "胎心监护", "内检"], preparations=[], notes="预防新生儿感染", importance="high"),
    CheckupItem(title="每周产检", week=37, items=["胎心监护", "血压", "体重", "宫高腹围"], preparations=[], notes="每周一次，准备待产", importance="medium"),
    CheckupItem(title="每周产检", week=38, items=["胎心监护", "B超评估", "血压", "体重"], preparations=[], notes="评估分娩时机", importance="medium"),
    CheckupItem(title="每周产检", week=39, items=["胎心监护", "血压", "体重", "宫颈评估"], preparations=[], notes="关注产兆", importance="high"),
    CheckupItem(title="预产期产检", week=40, items=["胎心监护", "B超", "血压", "体重", "催产评估"], preparations=[], notes="超过预产期需密切监护", importance="high"),
]


@router.get("/plan")
async def get_checkup_plan(user: User = Depends(get_current_user)):
    """获取产检计划"""
    plan = await CheckupPlan.find_one(CheckupPlan.user_id == user.id)

    if not plan:
        # Generate default plan
        plan = CheckupPlan(user_id=user.id, checkups=STANDARD_CHECKUPS)
        await plan.insert()

    # Mark completed checkups based on current week
    current_week = user.pregnancy_week or 0
    checkups = []
    for c in plan.checkups:
        status = c.status
        if c.week < current_week and status == "upcoming":
            status = "missed"
        checkups.append({
            **c.model_dump(),
            "status": status,
        })

    # Find next checkup
    next_checkup = None
    for c in checkups:
        if c["status"] == "upcoming":
            next_checkup = c
            break

    return {
        "checkups": checkups,
        "next_checkup": next_checkup,
        "current_week": current_week,
    }


@router.put("/plan/{week}/complete")
async def complete_checkup(week: int, user: User = Depends(get_current_user)):
    """标记产检已完成"""
    plan = await CheckupPlan.find_one(CheckupPlan.user_id == user.id)
    if not plan:
        raise HTTPException(status_code=404, detail="产检计划不存在")

    for checkup in plan.checkups:
        if checkup.week == week:
            checkup.status = "completed"
            break

    plan.updated_at = datetime.now(timezone.utc)
    await plan.save()
    return {"message": "已标记完成"}


async def link_report_to_checkup(user_id, report_id: str, pregnancy_week: int):
    """将报告自动关联到最近的产检（±2周窗口），并标记该产检为已完成"""
    plan = await CheckupPlan.find_one(CheckupPlan.user_id == user_id)
    if not plan:
        return

    best = None
    best_diff = 999
    for c in plan.checkups:
        diff = abs(c.week - pregnancy_week)
        if diff <= 2 and diff < best_diff:
            best = c
            best_diff = diff

    if best:
        if report_id not in best.report_ids:
            best.report_ids.append(report_id)
        best.status = "completed"
        plan.updated_at = datetime.now(timezone.utc)
        await plan.save()