feat(auth): M2 POST /wechat/conflict/rebind(换绑=注销X重建Y,单事务)

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

alembic/versions/comparison_llm_cost.py

@@ -0,0 +1,33 @@
+"""comparison_record: llm_cost_yuan + llm_price_snapshot(比价 LLM 调用成本 + 当时单价快照)
+
+回填 llm_calls 时按「当时的价」逐模型算出本次比价 LLM 总成本(元),连同所用单价快照一起冻结到
+记录上;admin 比价记录详情展示实际成本(旧记录 NULL → 前端回退估算)。见 services/llm_cost.py。
+
+Revision ID: comparison_llm_cost
+Revises: ad_ecpm_trace_id
+Create Date: 2026-07-13
+"""
+from collections.abc import Sequence
+
+import sqlalchemy as sa
+from sqlalchemy.dialects import postgresql
+
+from alembic import op
+
+revision: str = "comparison_llm_cost"
+down_revision: str | Sequence[str] | None = "ad_ecpm_trace_id"
+branch_labels: str | Sequence[str] | None = None
+depends_on: str | Sequence[str] | None = None
+
+_JSONB = sa.JSON().with_variant(postgresql.JSONB(), "postgresql")
+
+
+def upgrade() -> None:
+    # 均可空、无索引;SQLite 原生支持 ADD COLUMN,无需 batch_alter_table(同 comparison_debug_fields)。
+    op.add_column("comparison_record", sa.Column("llm_cost_yuan", sa.Float(), nullable=True))
+    op.add_column("comparison_record", sa.Column("llm_price_snapshot", _JSONB, nullable=True))
+
+
+def downgrade() -> None:
+    op.drop_column("comparison_record", "llm_price_snapshot")
+    op.drop_column("comparison_record", "llm_cost_yuan")

alembic/versions/phone_rebind_log.py

@@ -0,0 +1,32 @@
+"""phone_rebind_log 表(M2 换绑 30 天限制台账)
+
+Revision ID: phone_rebind_log
+Revises: comparison_llm_cost
+"""
+from alembic import op
+import sqlalchemy as sa
+
+revision = "phone_rebind_log"
+down_revision = "comparison_llm_cost"
+branch_labels = None
+depends_on = None
+
+
+def upgrade() -> None:
+    op.create_table(
+        "phone_rebind_log",
+        sa.Column("id", sa.Integer(), primary_key=True, autoincrement=True),
+        sa.Column("phone", sa.String(length=20), nullable=False),
+        sa.Column("old_user_id", sa.Integer(), nullable=True),
+        sa.Column("new_user_id", sa.Integer(), nullable=False),
+        sa.Column("source", sa.String(length=32), nullable=False, server_default="wechat_conflict"),
+        sa.Column("rebound_at", sa.DateTime(timezone=True), server_default=sa.func.now(), nullable=False),
+    )
+    op.create_index("ix_phone_rebind_log_phone", "phone_rebind_log", ["phone"])
+    op.create_index("ix_phone_rebind_log_rebound_at", "phone_rebind_log", ["rebound_at"])
+
+
+def downgrade() -> None:
+    op.drop_index("ix_phone_rebind_log_rebound_at", table_name="phone_rebind_log")
+    op.drop_index("ix_phone_rebind_log_phone", table_name="phone_rebind_log")
+    op.drop_table("phone_rebind_log")

app/admin/schemas/comparison.py

@@ -36,6 +36,8 @@ class AdminComparisonListItem(BaseModel):
     retry_count: int | None = None
     input_tokens: int | None = None      # Σ usage.prompt_tokens(server 派生)
     output_tokens: int | None = None     # Σ usage.completion_tokens(server 派生)
+    # 本次比价 LLM 总成本(元,按当时价冻结);旧记录/未回填为 None → 前端「成本」列回退估算。见 services/llm_cost.py。
+    llm_cost_yuan: float | None = None
     device_model: str | None = None
     rom_vendor: str | None = None
     rom_name: str | None = None
@@ -72,3 +74,5 @@ class AdminComparisonDetail(AdminComparisonListItem):
     # 原始上报全量;「卡在哪一步」从 raw_payload.platform_results[*].status 读
     # (store_not_found/items_not_found/below_minimum/unsupported = 卡在 找店/加菜/起送/读价)。
     raw_payload: dict | None = None
+    # 算成本所用单价快照 {mode, prices:{model:{...}}}(llm_cost_yuan 继承自列表项)。见 services/llm_cost.py。
+    llm_price_snapshot: dict | None = None

app/api/v1/auth.py

@@ -13,6 +13,7 @@ from __future__ import annotations
 import logging
 
 from fastapi import APIRouter, HTTPException, Request, status
+from sqlalchemy.exc import IntegrityError
 
 from app.api.deps import CurrentUser, DbSession
 from app.core import test_account
@@ -20,7 +21,9 @@ from app.core.ratelimit import enforce_rate_limit
 from app.core.security import (
     TokenError,
     create_bind_ticket,
+    create_conflict_ticket,
     decode_bind_ticket,
+    decode_conflict_ticket,
     decode_token,
     issue_token_pair,
 )
@@ -28,6 +31,7 @@ from app.integrations import wxpay
 from app.integrations.jiguang import JiguangError, mask_phone, verify_and_get_phone
 from app.integrations.sms import SmsError, send_code, verify_code
 from app.repositories import onboarding as onboarding_repo
+from app.repositories import phone_rebind as rebind_repo
 from app.repositories import user as user_repo
 from app.schemas.auth import (
     JverifyLoginRequest,
@@ -43,6 +47,8 @@ from app.schemas.auth import (
     WechatBindPhoneJverifyRequest,
     WechatBindPhoneSmsRequest,
     WechatBindResultResponse,
+    WechatConflictContinueRequest,
+    WechatConflictRebindRequest,
     WechatLoginRequest,
     WechatLoginResponse,
 )
@@ -240,13 +246,32 @@ def _finish_wechat_bind(
     未占用 → 新建微信账号(channel=wechat,昵称头像取微信)→ 签 token 登入。"""
     existing = user_repo.get_user_by_phone(db, phone)
     if existing is not None:
-        logger.info("wechat bind phone occupied phone=%s by user_id=%d", mask_phone(phone), existing.id)
+        from app.core.config import settings  # 局部 import,避免循环
+
+        ticket = create_conflict_ticket(
+            openid=openid,
+            wechat_nickname=wechat_nickname,
+            wechat_avatar_url=wechat_avatar_url,
+            phone=phone,
+        )
+        blocked = rebind_repo.rebound_within_days(db, phone, settings.PHONE_REBIND_LIMIT_DAYS)
+        logger.info(
+            "wechat bind phone occupied phone=%s by user_id=%d has_wechat=%s",
+            mask_phone(phone), existing.id, bool(existing.wechat_openid),
+        )
         return WechatBindResultResponse(
             status="phone_occupied",
             occupied_account=OccupiedAccountInfo(
                 nickname=existing.nickname,
                 avatar_url=existing.avatar_url,
                 created_at=existing.created_at,
+                has_wechat=bool(existing.wechat_openid),
+            ),
+            conflict_ticket=ticket,
+            rebind_available=not blocked,
+            rebind_blocked_days=(
+                rebind_repo.remaining_block_days(db, phone, settings.PHONE_REBIND_LIMIT_DAYS)
+                if blocked else 0
             ),
         )
     user = user_repo.create_wechat_user(
@@ -330,6 +355,91 @@ def wechat_bind_phone_jverify(
     )
 
 
+# ===================== 微信占用冲突(M2) =====================
+
+@router.post(
+    "/wechat/conflict/continue",
+    response_model=WechatBindResultResponse,
+    summary="微信占用冲突·继续绑定(登录老账号,能绑就绑)",
+)
+def wechat_conflict_continue(
+    req: WechatConflictContinueRequest, request: Request, db: DbSession
+) -> WechatBindResultResponse:
+    try:
+        claims = decode_conflict_ticket(req.conflict_ticket)
+    except TokenError as e:
+        raise HTTPException(status_code=401, detail="操作超时,请重新用微信登录") from e
+
+    enforce_rate_limit(
+        request, scope="wechat-conflict-device", subject=req.device_id,
+        limit=SMS_LOGIN_MAX_PER_HOUR, window_sec=3600, detail="操作过于频繁,请稍后再试",
+    )
+
+    user = user_repo.get_user_by_phone(db, claims["phone"])
+    if user is None:
+        # P 期间被腾空(老账号改号/注销)→ 前提已变,让前端重走
+        raise HTTPException(status_code=409, detail="账号状态已变化,请重新登录")
+    if user.status != "active":
+        raise HTTPException(status_code=403, detail="account disabled")
+
+    if user.wechat_openid is None:
+        try:
+            user_repo.attach_wechat_to_user(
+                db, user, openid=claims["openid"],
+                wechat_nickname=claims["wnk"], wechat_avatar_url=claims["wav"],
+            )
+        except IntegrityError:
+            db.rollback()  # openid 被别处绑走 → 只登入不绑
+            user_repo.touch_last_login(db, user)
+    else:
+        user_repo.touch_last_login(db, user)  # X 已绑别的微信 → 只登入,丢弃本次 openid
+
+    completed = onboarding_repo.is_completed(db, user_id=user.id, device_id=req.device_id)
+    logger.info("wechat conflict continue user_id=%d openid=%s***", user.id, claims["openid"][:6])
+    return WechatBindResultResponse(
+        status="logged_in",
+        token=_login_response(user, onboarding_completed=completed),
+    )
+
+
+@router.post(
+    "/wechat/conflict/rebind",
+    response_model=WechatBindResultResponse,
+    summary="微信占用冲突·换绑(注销老账号+用该号重建全新账号)",
+)
+def wechat_conflict_rebind(
+    req: WechatConflictRebindRequest, request: Request, db: DbSession
+) -> WechatBindResultResponse:
+    from app.core.config import settings  # 局部 import,避免循环
+
+    try:
+        claims = decode_conflict_ticket(req.conflict_ticket)
+    except TokenError as e:
+        raise HTTPException(status_code=401, detail="操作超时,请重新用微信登录") from e
+
+    enforce_rate_limit(
+        request, scope="wechat-conflict-device", subject=req.device_id,
+        limit=SMS_LOGIN_MAX_PER_HOUR, window_sec=3600, detail="操作过于频繁,请稍后再试",
+    )
+
+    phone = claims["phone"]
+    if rebind_repo.rebound_within_days(db, phone, settings.PHONE_REBIND_LIMIT_DAYS):
+        days = rebind_repo.remaining_block_days(db, phone, settings.PHONE_REBIND_LIMIT_DAYS)
+        raise HTTPException(status_code=409, detail=f"该手机号 {days} 天内已换绑过,暂不能再次换绑")
+
+    user = user_repo.rebind_account(
+        db, phone=phone, openid=claims["openid"],
+        wechat_nickname=claims["wnk"], wechat_avatar_url=claims["wav"],
+    )
+    completed = onboarding_repo.is_completed(db, user_id=user.id, device_id=req.device_id)
+    logger.info("wechat conflict rebind new_user_id=%d phone=%s openid=%s***",
+                user.id, mask_phone(phone), claims["openid"][:6])
+    return WechatBindResultResponse(
+        status="logged_in",
+        token=_login_response(user, onboarding_completed=completed),
+    )
+
+
 # ===================== Refresh =====================
 
 @router.post("/refresh", response_model=TokenPair, summary="用 refresh_token 换新 token 对")

app/api/v1/compare_record.py

@@ -27,6 +27,7 @@ from app.schemas.compare_record import (
     ComparisonRecordOut,
     ComparisonRecordPage,
 )
+from app.services.llm_cost import compute_llm_cost, get_llm_prices
 from app.services.pricebot_llm_calls import fetch_llm_calls
 
 logger = logging.getLogger("shagua.compare_record")
@@ -81,6 +82,8 @@ def _backfill_llm_calls(record_id: int, trace_id: str) -> None:
         # error 的调用 usage 可能为 None,or {} 兜底)
         rec.input_tokens = sum((c.get("usage") or {}).get("prompt_tokens") or 0 for c in calls)
         rec.output_tokens = sum((c.get("usage") or {}).get("completion_tokens") or 0 for c in calls)
+        # 本次比价 LLM 成本(元)+ 当时单价快照:按 app_config 现价逐模型算好冻结(services/llm_cost.py)。
+        rec.llm_cost_yuan, rec.llm_price_snapshot = compute_llm_cost(calls, get_llm_prices(db))
         db.commit()
         logger.info(
             "backfill llm_calls trace=%s n=%d in_tok=%d out_tok=%d",

app/core/config.py

@@ -44,9 +44,11 @@ class Settings(BaseSettings):
     JWT_ALGORITHM: str = "HS256"
     JWT_ACCESS_TOKEN_EXPIRE_MINUTES: int = 120
     JWT_REFRESH_TOKEN_EXPIRE_DAYS: int = 30
-    # 微信登录未命中 openid 时签发的"待绑手机"令牌有效期(分钟)。
-    # 见 auth.wechat_login / security.create_bind_ticket。
+    # 微信登录未命中 openid 时签发的"待绑手机"令牌有效期(JWT_SECRET_KEY 签名,typ=wechat_bind;
+    # 见 security.create_bind_ticket)。需覆盖"授权→输手机号→收短信→输验证码"整个绑定流程。
     WECHAT_BIND_TICKET_EXPIRE_MINUTES: int = 10
+    # 一个手机号 30 天内最多换绑一次(微信占用冲突页的"换绑"动作)。见 phone_rebind_log。
+    PHONE_REBIND_LIMIT_DAYS: int = 30
 
     # ===== Admin 后台 =====
     # admin 用独立 JWT secret(≠ JWT_SECRET_KEY),App 用户 token 无法越权访问后台。
@@ -84,6 +86,7 @@ class Settings(BaseSettings):
     SMS_SIGN_ID: int = 31729       # 极光短信签名 ID(非机密,可被 .env 覆盖)
     SMS_TEMPLATE_ID: int = 1       # 极光短信模板 ID(变量名 code,有效期 5 分钟)
     SMS_CODE_LENGTH: int = 6       # 验证码位数(本服务生成;前端 code 字段 4-8 位兼容)
+    SMS_DAILY_LIMIT_PER_PHONE: int = 10   # 单手机号每日发送上限(防刷 + 控费)
     SMS_MAX_VERIFY_ATTEMPTS: int = 5      # 单个验证码最多校验失败次数,超过即作废(防爆破)
 
     # ===== 测试账号(release 包全流程联调用)=====
@@ -109,6 +112,9 @@ class Settings(BaseSettings):
     # 美团调用走的代理。本机开发直连美团会 SSL EOF,需填 http://127.0.0.1:7897;
     # 线上国内服务器留空(=直连)。见 .env.example 与 integrations/meituan.py。
     MT_CPS_PROXY: str = ""
+    # 本地开发:开启后 /feed 接口直接返回 mock 数据,不调美团 API、不查离线库,
+    # 方便前端联调 feed 卡片样式、分页、距离排序等 UI。生产必须 false。
+    MT_CPS_MOCK_FEED: bool = True
 
     @property
     def mt_cps_configured(self) -> bool:

app/core/config_schema.py

@@ -96,4 +96,19 @@ CONFIG_DEFS: dict[str, dict[str, Any]] = {
         "group": "首页轮播", "type": "enum", "hidden": True,
         "help": "mixed=真实优先+种子补位(默认);real=只用真实比价记录;seed=只用种子/合成(演示)。",
     },
+    # 比价 LLM 调用成本计价。值是嵌套 JSON(非 str→int),借 dict_str_int 类型在配置页走原始 JSON
+    # 编辑框;set_value 不校验类型,嵌套 JSON 照存。
+    "llm_token_price": {
+        "default": {
+            "per_model": {"qwen3.5-flash": {"input_per_1m": 0.8, "output_per_1m": 2.0}},
+            "default": {"input_per_1m": 3.0, "output_per_1m": 15.0},
+            "currency": "CNY", "unit": "per_1m_tokens",
+        },
+        "label": "LLM 模型单价(元/百万 token)",
+        "group": "LLM 成本", "type": "dict_str_int",
+        "help": (
+            "比价 LLM 调用成本计价。JSON:per_model 按模型配 input/output 单价(元/1M token),"
+            "default 兜底未登记的模型。改价只影响之后回填的新记录,历史记录用当时价格快照。"
+        ),
+    },
 }

app/core/security.py

@@ -126,6 +126,52 @@ def decode_bind_ticket(token: str) -> dict[str, Any]:
     return {"openid": payload["sub"], "wnk": payload.get("wnk"), "wav": payload.get("wav")}
 
 
+def create_conflict_ticket(
+    *, openid: str, wechat_nickname: str | None, wechat_avatar_url: str | None, phone: str
+) -> str:
+    """手机号占用时签发的短时"冲突处理"令牌。
+
+    比 bind_ticket 多编码 **已验证的手机号 phone** —— 换绑/继续绑定只认它,证明"这对
+    openid/手机号刚在绑号时验证通过",免用户重输验证码,又堵住"拿自己 openid + 任意手机号
+    去夺号"的接管漏洞。typ='wechat_conflict';有效期复用 WECHAT_BIND_TICKET_EXPIRE_MINUTES。
+    """
+    now = _now()
+    expire = now + timedelta(minutes=settings.WECHAT_BIND_TICKET_EXPIRE_MINUTES)
+    payload: dict[str, Any] = {
+        "sub": openid,
+        "typ": "wechat_conflict",
+        "wnk": wechat_nickname,
+        "wav": wechat_avatar_url,
+        "phn": phone,
+        "iat": int(now.timestamp()),
+        "exp": int(expire.timestamp()),
+    }
+    return jwt.encode(payload, settings.JWT_SECRET_KEY, algorithm=settings.JWT_ALGORITHM)
+
+
+def decode_conflict_ticket(token: str) -> dict[str, Any]:
+    """解析"冲突处理"令牌,校验签名/过期/类型。失败抛 TokenError。
+
+    返回 {'openid': str, 'wnk': str|None, 'wav': str|None, 'phone': str}。
+    """
+    try:
+        payload = jwt.decode(token, settings.JWT_SECRET_KEY, algorithms=[settings.JWT_ALGORITHM])
+    except jwt.ExpiredSignatureError as e:
+        raise TokenError("conflict ticket expired") from e
+    except jwt.InvalidTokenError as e:
+        raise TokenError(f"invalid conflict ticket: {e}") from e
+    if payload.get("typ") != "wechat_conflict":
+        raise TokenError(f"wrong token type: want=wechat_conflict got={payload.get('typ')}")
+    if "sub" not in payload or "phn" not in payload:
+        raise TokenError("conflict ticket missing sub/phn")
+    return {
+        "openid": payload["sub"],
+        "wnk": payload.get("wnk"),
+        "wav": payload.get("wav"),
+        "phone": payload["phn"],
+    }
+
+
 # ===================== 密码 hash(admin 后台账号用)=====================
 # 用户侧是手机号+验证码登录,不存密码;仅 admin 账号用 username+password 登录。
 

app/models/__init__.py

@@ -32,6 +32,7 @@ from app.models.invite_fingerprint import InviteFingerprint  # noqa: F401
 from app.models.launch_confirm_sample import LaunchConfirmSample  # noqa: F401
 from app.models.meituan_coupon import MeituanCoupon  # noqa: F401
 from app.models.onboarding import OnboardingCompletion  # noqa: F401
+from app.models.phone_rebind_log import PhoneRebindLog  # noqa: F401
 from app.models.ops_marquee_seed import OpsMarqueeSeed  # noqa: F401
 from app.models.ops_stat_config import OpsStatConfig  # noqa: F401
 from app.models.price_observation import PriceObservation  # noqa: F401

app/models/comparison.py

@@ -137,6 +137,12 @@ class ComparisonRecord(Base):
     # 每次 LLM 调用明细 [{scene,model,input_messages,output,usage,latency_ms,error}];
     # server 收上报后按 trace_id 同机拉 pricebot 落库(见 compare_record 端点)。旧记录/未采集为 None。
     llm_calls: Mapped[list | None] = mapped_column(_JSON, nullable=True)
+    # 本次比价 LLM 总成本(元):回填时按「当时的价」逐模型算好冻结(见 services/llm_cost.py)。
+    # 单次亚分级 → float「元」(不用 *_cents)。旧记录/未回填为 None,前端回退「估算成本」。
+    llm_cost_yuan: Mapped[float | None] = mapped_column(Float, nullable=True)
+    # 算成本所用单价快照 {mode, prices:{model:{input_per_1m,output_per_1m,_source}}}:app_config 只存
+    # 当前价、不留历史,故把当时价冻结进来供审计/复算。
+    llm_price_snapshot: Mapped[dict | None] = mapped_column(_JSON, nullable=True)
 
     created_at: Mapped[datetime] = mapped_column(
         DateTime(timezone=True), server_default=func.now(), index=True, nullable=False

app/models/phone_rebind_log.py

@@ -0,0 +1,31 @@
+"""手机号换绑台账。
+
+记录"手机号从老账号被夺走、重建为新账号(X 注销 → Y)"这一破坏性事件,支撑"一个手机号
+30 天内最多换绑一次"的限制。手机号级、渠道无关(source 标来源);普通微信绑定不写此表。
+见 M2 spec §4.1。
+"""
+from __future__ import annotations
+
+from datetime import datetime
+
+from sqlalchemy import DateTime, Integer, String, func
+from sqlalchemy.orm import Mapped, mapped_column
+
+from app.db.base import Base
+
+
+class PhoneRebindLog(Base):
+    __tablename__ = "phone_rebind_log"
+
+    id: Mapped[int] = mapped_column(Integer, primary_key=True, autoincrement=True)
+    # 被换绑的真实手机号(注意:存真实号,不是老账号被腾号后的 deleted_<id>)
+    phone: Mapped[str] = mapped_column(String(20), index=True, nullable=False)
+    # 被注销的老账号 X;P 换绑时已被腾空(极边界)则为空
+    old_user_id: Mapped[int | None] = mapped_column(Integer, nullable=True)
+    # 换绑后新建的账号 Y
+    new_user_id: Mapped[int] = mapped_column(Integer, nullable=False)
+    # 换绑来源。手机号级配额、渠道无关,留字段给未来其他换绑路径共用同一份 30 天限制。
+    source: Mapped[str] = mapped_column(String(32), nullable=False, default="wechat_conflict")
+    rebound_at: Mapped[datetime] = mapped_column(
+        DateTime(timezone=True), server_default=func.now(), index=True, nullable=False
+    )

app/repositories/phone_rebind.py

@@ -0,0 +1,39 @@
+"""手机号换绑台账(phone_rebind_log)的查询与写入。见 M2 spec §4.1。"""
+from __future__ import annotations
+
+import math
+from datetime import datetime, timedelta, timezone
+
+from sqlalchemy import func, select
+from sqlalchemy.orm import Session
+
+from app.models.phone_rebind_log import PhoneRebindLog
+
+
+def rebound_within_days(db: Session, phone: str, days: int) -> bool:
+    """该手机号在最近 days 天内是否换绑过(命中 → 禁止再次换绑)。"""
+    since = datetime.now(timezone.utc) - timedelta(days=days)
+    stmt = (
+        select(PhoneRebindLog.id)
+        .where(PhoneRebindLog.phone == phone, PhoneRebindLog.rebound_at >= since)
+        .limit(1)
+    )
+    return db.execute(stmt).first() is not None
+
+
+def remaining_block_days(db: Session, phone: str, days: int) -> int:
+    """距离该手机号可再次换绑还剩几天(向上取整;无记录返回 0)。"""
+    last = db.execute(
+        select(func.max(PhoneRebindLog.rebound_at)).where(PhoneRebindLog.phone == phone)
+    ).scalar_one_or_none()
+    if last is None:
+        return 0
+    if last.tzinfo is None:  # SQLite 取回 naive datetime,按 UTC 归一
+        last = last.replace(tzinfo=timezone.utc)
+    remaining = (last + timedelta(days=days) - datetime.now(timezone.utc)).total_seconds()
+    return max(0, math.ceil(remaining / 86400))
+
+
+def add_rebind_log(db: Session, *, phone: str, old_user_id: int | None, new_user_id: int, source: str) -> None:
+    """写一条换绑台账(**不 commit**,交给调用方 rebind_account 的单事务)。"""
+    db.add(PhoneRebindLog(phone=phone, old_user_id=old_user_id, new_user_id=new_user_id, source=source))

app/repositories/user.py

@@ -12,6 +12,7 @@ from sqlalchemy import select
 from sqlalchemy.orm import Session
 
 from app.models.user import User
+from app.repositories import phone_rebind
 
 
 # ===== 创建时分配的标识:用户名(对外展示账号 ID)+ 默认昵称 =====
@@ -99,7 +100,25 @@ def touch_last_login(db: Session, user: User) -> User:
     return user
 
 
-def create_wechat_user(
+def attach_wechat_to_user(
+    db: Session, user: User, *, openid: str, wechat_nickname: str | None, wechat_avatar_url: str | None
+) -> User:
+    """继续绑定:把微信 openid + 微信源字段并入已存在账号(调用方保证 user.wechat_openid 为空)。
+
+    **只写 wechat_openid / wechat_nickname / wechat_avatar_url,不动展示 nickname/avatar_url**
+    (完整 §10"默认则用微信、改过则保留"规则留 M3)。撞 openid 唯一约束(O 期间被别处绑走,
+    极罕见)时由调用方捕获 IntegrityError 兜底降级为"只登入不绑"。
+    """
+    user.wechat_openid = openid
+    user.wechat_nickname = wechat_nickname
+    user.wechat_avatar_url = wechat_avatar_url
+    user.last_login_at = datetime.now(timezone.utc)
+    db.commit()
+    db.refresh(user)
+    return user
+
+
+def _build_wechat_user(
     db: Session,
     *,
     phone: str,
@@ -107,12 +126,8 @@ def create_wechat_user(
     wechat_nickname: str | None,
     wechat_avatar_url: str | None,
 ) -> User:
-    """微信登录新建账号:register_channel='wechat';展示昵称/头像取微信(§10 新注册),
-    昵称缺失(微信隐私脱敏返回 None)时退默认昵称。同时保存 wechat_* 源字段。
-
-    openid 唯一约束是并发/重复绑定的最终防线(极罕见,openid 在 wechat-login 刚查过为空)。
-    """
-    now = datetime.now(timezone.utc)
+    """构造并 db.add 一个微信账号行(register_channel='wechat',展示昵称头像取微信,缺则默认),
+    **不 commit**。create_wechat_user 与 rebind_account 共用,保证建号逻辑单一来源。"""
     user = User(
         phone=phone,
         username=_gen_unique_username(db),
@@ -122,9 +137,28 @@ def create_wechat_user(
         wechat_openid=openid,
         wechat_nickname=wechat_nickname,
         wechat_avatar_url=wechat_avatar_url,
-        last_login_at=now,
+        last_login_at=datetime.now(timezone.utc),
     )
     db.add(user)
+    return user
+
+
+def create_wechat_user(
+    db: Session,
+    *,
+    phone: str,
+    openid: str,
+    wechat_nickname: str | None,
+    wechat_avatar_url: str | None,
+) -> User:
+    """微信登录新建账号(未占用分支)。见 _build_wechat_user。
+
+    openid 唯一约束是并发/重复绑定的最终防线(极罕见,openid 在 wechat-login 刚查过为空)。
+    """
+    user = _build_wechat_user(
+        db, phone=phone, openid=openid,
+        wechat_nickname=wechat_nickname, wechat_avatar_url=wechat_avatar_url,
+    )
     db.commit()
     db.refresh(user)
     return user
@@ -198,3 +232,44 @@ def soft_delete_account(db: Session, user: User) -> None:
     # 释放邀请码唯一槽
     user.invite_code = None
     db.commit()
+
+
+def rebind_account(
+    db: Session,
+    *,
+    phone: str,
+    openid: str,
+    wechat_nickname: str | None,
+    wechat_avatar_url: str | None,
+    source: str = "wechat_conflict",
+) -> User:
+    """换绑:**单事务内**注销老账号 X(腾出手机号)+ 用该号建全新微信账号 Y + 写换绑台账。
+
+    - 老账号可能已不存在(P 被腾空)→ old_user_id=None,直接建 Y(幂等更稳)。
+    - 手机号唯一约束靠时序:先把 X.phone 改名并 flush 腾号,再插 Y。
+    - 全程不中途 commit,任一步失败整体回滚,绝不出现"X 删了 Y 没建"。
+    X 的字段变更等价 soft_delete_account(软删 + 匿名化 + 释放 openid/邀请码唯一槽),但不在此 commit。
+    """
+    old = get_user_by_phone(db, phone)
+    old_id = old.id if old is not None else None
+    if old is not None:
+        old.status = "deleted"
+        old.phone = f"deleted_{old.id}"
+        old.nickname = None
+        old.avatar_url = None
+        old.wechat_openid = None
+        old.wechat_nickname = None
+        old.wechat_avatar_url = None
+        old.invite_code = None
+        db.flush()  # 先落 phone 改名,腾出手机号唯一约束,才能给 Y 用
+    new_user = _build_wechat_user(
+        db, phone=phone, openid=openid,
+        wechat_nickname=wechat_nickname, wechat_avatar_url=wechat_avatar_url,
+    )
+    db.flush()  # 拿 new_user.id
+    phone_rebind.add_rebind_log(
+        db, phone=phone, old_user_id=old_id, new_user_id=new_user.id, source=source
+    )
+    db.commit()
+    db.refresh(new_user)
+    return new_user

app/schemas/auth.py

@@ -124,18 +124,22 @@ class WechatLoginResponse(BaseModel):
 
 
 class OccupiedAccountInfo(BaseModel):
-    """手机号被占用时返回的原账号脱敏展示信息(供 M2 冲突页;M1 客户端仅用于提示)。"""
+    """手机号被占用时返回的原账号脱敏展示信息(供冲突页)。"""
     nickname: str | None = None
     avatar_url: str | None = None
     created_at: datetime
+    has_wechat: bool = False
 
 
 class WechatBindResultResponse(BaseModel):
     # status="logged_in" → 未占用,已建号登入,token 有值;
-    # "phone_occupied" → 手机号被占用,occupied_account 有值,token 为 None
+    # "phone_occupied" → 手机号被占用,occupied_account + conflict_ticket 有值,token 为 None
     status: str
     token: TokenWithUser | None = None
     occupied_account: OccupiedAccountInfo | None = None
+    conflict_ticket: str | None = None            # 占用时签发,换绑/继续绑定只认它
+    rebind_available: bool | None = None          # 该手机号 30 天内是否还能换绑(给换绑按钮预置禁用态)
+    rebind_blocked_days: int | None = None        # 被限时剩余天数(rebind_available=False 时>0)
 
 
 class WechatBindPhoneSmsRequest(BaseModel):
@@ -149,3 +153,13 @@ class WechatBindPhoneJverifyRequest(BaseModel):
     bind_ticket: str = Field(..., min_length=1)
     login_token: str = Field(..., min_length=1, description="客户端 loginAuth 拿到的 loginToken")
     device_id: str = Field("", max_length=64)
+
+
+class WechatConflictContinueRequest(BaseModel):
+    conflict_ticket: str = Field(..., min_length=1)
+    device_id: str = Field("", max_length=64)
+
+
+class WechatConflictRebindRequest(BaseModel):
+    conflict_ticket: str = Field(..., min_length=1)
+    device_id: str = Field("", max_length=64)

app/services/llm_cost.py

@@ -0,0 +1,53 @@
+"""LLM 调用成本计算(纯逻辑,无 DB):按 model 分桶累加 token × 单价,返回总成本(元)+ 价格快照。
+
+用量取自 comparison_record.llm_calls[].usage(pricebot 已归一为 prompt/completion_tokens);
+error / 无 usage 的调用跳过。price_cfg = {per_model:{model:{input_per_1m,output_per_1m}}, default:{...}}。
+成本单位「元」——单次亚分级,用 float(不用 *_cents);snapshot 只含本次用到的模型的价(审计用,
+不存整张价表)。用到但没配价(既无 per_model 又无 default)的模型 → 快照标 unpriced,成本按 0 计。
+"""
+from __future__ import annotations
+
+_PRICE_KEY = "llm_token_price"
+
+
+def get_llm_prices(db) -> dict:
+    """读 LLM 单价配置(app_config;表内无则回退 CONFIG_DEFS 默认)。返回 compute_llm_cost 的 price_cfg。"""
+    from app.repositories import app_config  # 延迟 import:compute_llm_cost 纯逻辑不牵连 DB 层
+    return app_config.get_value(db, _PRICE_KEY)
+
+
+def compute_llm_cost(calls: list[dict], price_cfg: dict) -> tuple[float | None, dict | None]:
+    """遍历 calls 按 model 分桶,cost = Σ(入/1e6*入价 + 出/1e6*出价);无有效调用 → (None, None)。"""
+    if not calls:
+        return None, None
+    per_model = price_cfg.get("per_model") or {}
+    default = price_cfg.get("default")
+    buckets: dict[str, list[int]] = {}  # model -> [Σprompt_tokens, Σcompletion_tokens]
+    for c in calls:
+        if c.get("error"):
+            continue
+        usage = c.get("usage") or {}
+        model = c.get("model") or "unknown"
+        b = buckets.setdefault(model, [0, 0])
+        b[0] += usage.get("prompt_tokens") or 0
+        b[1] += usage.get("completion_tokens") or 0
+    if not buckets:  # 全是 error / 无 usage
+        return None, None
+    total = 0.0
+    prices: dict[str, dict] = {}
+    for model, (tin, tout) in buckets.items():
+        price = per_model.get(model, default)
+        in_p = price.get("input_per_1m") if isinstance(price, dict) else None
+        out_p = price.get("output_per_1m") if isinstance(price, dict) else None
+        # 没配价 / 无 default / 单价残缺或非法(配置页手改 JSON 可能存出脏数据)→ 标记待补价、
+        # 不计入成本;绝不抛异常,以免连累同一回填里的 token/llm_calls 落库。
+        if not isinstance(in_p, (int, float)) or not isinstance(out_p, (int, float)):
+            prices[model] = {"input_per_1m": in_p, "output_per_1m": out_p, "unpriced": True}
+            continue
+        total += tin / 1e6 * in_p + tout / 1e6 * out_p
+        prices[model] = {
+            "input_per_1m": in_p,
+            "output_per_1m": out_p,
+            "_source": "per_model" if model in per_model else "default",
+        }
+    return round(total, 6), {"mode": "per_model", "prices": prices}

docs/database/comparison_record.md

@@ -40,6 +40,8 @@
 | `raw_payload` | JSON(PG: JSONB) | nullable | 客户端原始上报全量(calibration + done.params),取数兜底 |
 | `input_tokens` | Integer | nullable | 本次 LLM 累计输入 token = Σ `llm_calls[].usage.prompt_tokens`(server 收上报后从 `llm_calls` 累加;旧记录/未采集为 null) |
 | `output_tokens` | Integer | nullable | 本次 LLM 累计输出 token = Σ `llm_calls[].usage.completion_tokens`(同上) |
+| `llm_cost_yuan` | Float | nullable | 本次比价 LLM 总成本(元),回填时按「当时价」逐模型算好冻结(见 `services/llm_cost.py`);旧记录/未回填为 null → 前端回退「估算成本」 |
+| `llm_price_snapshot` | JSON(PG: JSONB) | nullable | 算成本所用单价快照 `{mode, prices:{model:{input_per_1m,output_per_1m,_source}}}`;`app_config` 只存当前价、不留历史,故冻结当时价供审计/复算 |
 | `created_at` | DateTime(tz) | server_default now(), index | 时间 |
 
 > `ordered`(已下单)是**瞬态字段**,不在表里:`list_records` 读取时按 `store_name ∈ 该用户 source='compare' 的 savings_record.shop_name 集合` 现挂到实例上供出参用。

scripts/seed_mock_llm_cost.py

@@ -0,0 +1,248 @@
+"""一次性 mock:造带 LLM token 成本的比价记录 + 配好 app_config 模型单价,用于测「管理后端」LLM 成本展示。
+
+覆盖 admin「比价记录」详情抽屉的「LLM 成本」展示分支:
+  • app_config.llm_token_price ← 写一条多模型单价(= 配置页「LLM 成本」卡片「已改」态,get_llm_prices 读它)
+  • comparison_record ← 造 5 条,逐条**复用生产的 compute_llm_cost + 与 _backfill_llm_calls 同款派生**
+    (llm_call_count/retry_count/input_tokens/output_tokens/llm_cost_yuan/llm_price_snapshot),
+    确保 mock 行 = 真实回填产出。5 条刻意覆盖:
+      ① 单模型真实样本(qwen3.5-flash ×4) → ¥0.006184(核对精确值)
+      ② 多模型(flash + plus)          → 快照含两个模型、各自 _source=per_model
+      ③ 未登记模型(deepseek-v3)        → 走 default,快照 _source=default
+      ④ 旧记录(有 token、无 cost)       → llm_cost_yuan=NULL → 前端回退「估算成本」
+      ⑤ 含 error 调用                    → error 那次跳过计费、retry_count+1
+
+记录挂到库里第一个真实用户(admin 列表能显示手机号);无用户则 user_id=NULL(孤儿行,admin 照样全看)。
+created_at 用北京 naive、最近几分钟内错开,详情列表倒序即 ①→⑤ 置顶。
+
+幂等:重跑先按 trace_id 前缀「MOCKLLM-」清旧再建。app_config 单价是 upsert(不随 --clean-only 删,
+因该 key 本就是本需求新增、无历史真实值;要改价直接去配置页或重跑本脚本)。
+
+  python -m scripts.seed_mock_llm_cost              # 造价格 + 5 条记录
+  python -m scripts.seed_mock_llm_cost --clean-only # 只清 MOCKLLM- 记录(保留单价)
+
+验收:admin「比价记录」→ 找 trace「MOCKLLM-」的 5 条 → 点开详情看「LLM 成本」:
+  ①②③⑤ 显示「实际·当时价」+ 价格快照;④ 显示「估算」。
+"""
+from __future__ import annotations
+
+import argparse
+import sys
+from datetime import datetime, timedelta, timezone
+
+from sqlalchemy import delete, select
+
+from app.db.session import SessionLocal
+from app.models.comparison import ComparisonRecord
+from app.models.user import User
+from app.repositories import app_config
+from app.services.llm_cost import compute_llm_cost
+
+if hasattr(sys.stdout, "reconfigure"):
+    sys.stdout.reconfigure(encoding="utf-8")  # Windows 控制台输出中文/¥
+
+_BJ = timezone(timedelta(hours=8))
+ID_PREFIX = "MOCKLLM-"
+
+# ── 写进 app_config 的模型单价(get_llm_prices 读它;配置页「LLM 成本」卡片可再改)──
+PRICE_CFG = {
+    "per_model": {
+        "qwen3.5-flash": {"input_per_1m": 0.8, "output_per_1m": 2.0},
+        "qwen3.5-plus": {"input_per_1m": 4.0, "output_per_1m": 12.0},
+    },
+    "default": {"input_per_1m": 3.0, "output_per_1m": 15.0},
+    "currency": "CNY",
+    "unit": "per_1m_tokens",
+}
+
+
+def _c(scene: str, model: str, pin: int, cout: int, error: str | None = None) -> dict:
+    """一条 llm_calls 明细,结构对齐真实 pricebot 归一后契约:
+    {scene, model, input_messages:[{role,content}], output, usage:{prompt/completion/total_tokens},
+     latency_ms, error}(详情抽屉会遍历 input_messages,缺了会崩)。error 的调用无 usage/output。"""
+    return {
+        "scene": scene,
+        "model": model,
+        "error": error,
+        "input_messages": [
+            {"role": "system", "content": f"你是比价助手,负责 {scene} 环节。"},
+            {"role": "user", "content": f"[mock] 请处理本次比价的 {scene} 任务。"},
+        ],
+        "output": None if error else f"[mock] {scene} 环节完成。",
+        "usage": None if error else {
+            "prompt_tokens": pin, "completion_tokens": cout, "total_tokens": pin + cout,
+        },
+        "latency_ms": 780,
+    }
+
+
+# ── 5 条记录蓝本:calls 决定成本;freeze=False 模拟旧记录(有 token 无 cost)──
+RECORDS = [
+    {
+        "label": "①单模型·真实样本",
+        "source": ("美团外卖", 4280), "best": ("京东秒送", 3680),
+        "store": "肯德基(建国路店)", "product": "疯狂星期四全家桶",
+        "info": "在京东秒送找到同款,到手价 ¥36.80,省 ¥6.00",
+        "freeze": True,
+        "calls": [
+            _c("store_match", "qwen3.5-flash", 1512, 22),
+            _c("dish_match", "qwen3.5-flash", 2111, 160),
+            _c("dish_match", "qwen3.5-flash", 1940, 142),
+            _c("summary", "qwen3.5-flash", 1325, 13),
+        ],
+    },
+    {
+        "label": "②多模型·flash+plus",
+        "source": ("淘宝闪购", 5900), "best": ("美团外卖", 5200),
+        "store": "瑞幸咖啡(国贸店)", "product": "生椰拿铁×2、丝绒拿铁",
+        "info": "在美团外卖找到同款,到手价 ¥52.00,省 ¥7.00",
+        "freeze": True,
+        "calls": [
+            _c("store_match", "qwen3.5-flash", 2000, 50),
+            _c("dish_match", "qwen3.5-flash", 1800, 40),
+            _c("reasoning", "qwen3.5-plus", 3000, 500),
+        ],
+    },
+    {
+        "label": "③未登记模型走 default",
+        "source": ("京东秒送", 3100), "best": ("美团外卖", 2650),
+        "store": "麦当劳(soho店)", "product": "麦辣鸡腿堡套餐",
+        "info": "在美团外卖找到同款,到手价 ¥26.50,省 ¥4.50",
+        "freeze": True,
+        "calls": [
+            _c("store_match", "deepseek-v3", 5000, 800),
+        ],
+    },
+    {
+        "label": "④旧记录·有token无成本(回退估算)",
+        "source": ("美团外卖", 3600), "best": ("淘宝闪购", 3200),
+        "store": "华莱士(双井店)", "product": "全鸡汉堡套餐",
+        "info": "在淘宝闪购找到同款,到手价 ¥32.00,省 ¥4.00",
+        "freeze": False,  # 模拟本需求上线前的老记录:llm_cost_yuan=NULL → 前端回退估算
+        "calls": [
+            _c("store_match", "qwen3.5-flash", 2000, 100),
+        ],
+    },
+    {
+        "label": "⑤含 error 调用(跳过计费)",
+        "source": ("淘宝闪购", 4100), "best": ("京东秒送", 3750),
+        "store": "海底捞(合生汇店)", "product": "番茄锅底、肥牛卷",
+        "info": "在京东秒送找到同款,到手价 ¥37.50,省 ¥3.50",
+        "freeze": True,
+        "calls": [
+            _c("store_match", "qwen3.5-flash", 0, 0, error="timeout"),
+            _c("store_match", "qwen3.5-flash", 1500, 30),
+        ],
+    },
+]
+
+_PLATFORM_ID = {  # 展示名 → 平台代号(comparison_results / source/best 列用)
+    "美团外卖": "meituan", "京东秒送": "jd", "淘宝闪购": "taobao",
+}
+
+
+def _naive_bj_now() -> datetime:
+    return datetime.now(_BJ).replace(tzinfo=None)
+
+
+def clean(db) -> int:
+    n = db.execute(
+        delete(ComparisonRecord).where(ComparisonRecord.trace_id.like(f"{ID_PREFIX}%"))
+    ).rowcount or 0
+    db.commit()
+    return n
+
+
+def _build_record(spec: dict, owner_id: int | None, created_at: datetime) -> tuple[ComparisonRecord, float | None]:
+    """按蓝本造一条记录,LLM 派生完全对齐 _backfill_llm_calls;返回 (记录, 冻结成本或 None)。"""
+    calls = spec["calls"]
+    src_name, src_cents = spec["source"]
+    best_name, best_cents = spec["best"]
+
+    # —— 与 _backfill_llm_calls 同款派生 ——
+    llm_call_count = len(calls)
+    retry_count = sum(1 for c in calls if c.get("error"))
+    input_tokens = sum((c.get("usage") or {}).get("prompt_tokens") or 0 for c in calls)
+    output_tokens = sum((c.get("usage") or {}).get("completion_tokens") or 0 for c in calls)
+    if spec["freeze"]:
+        cost, snapshot = compute_llm_cost(calls, PRICE_CFG)  # 复用生产纯函数
+    else:
+        cost, snapshot = None, None  # 旧记录:回填这段代码上线前就有,只有 token 没成本
+
+    rec = ComparisonRecord(
+        user_id=owner_id,
+        device_id=f"{ID_PREFIX.lower()}dev",
+        business_type="food",
+        trace_id=f"{ID_PREFIX}{spec['label'][0]}",  # ①..⑤ 各一,唯一
+        status="success",
+        source_platform_id=_PLATFORM_ID.get(src_name), source_platform_name=src_name,
+        source_price_cents=src_cents,
+        best_platform_id=_PLATFORM_ID.get(best_name), best_platform_name=best_name,
+        best_price_cents=best_cents,
+        saved_amount_cents=src_cents - best_cents,
+        is_source_best=False,
+        store_name=spec["store"],
+        product_names=spec["product"],
+        information=spec["info"],
+        items=[{"name": spec["product"], "qty": 1}],
+        comparison_results=[
+            {"platform_id": _PLATFORM_ID.get(src_name), "platform_name": src_name,
+             "price": src_cents / 100, "is_source": True, "rank": 2},
+            {"platform_id": _PLATFORM_ID.get(best_name), "platform_name": best_name,
+             "price": best_cents / 100, "is_source": False, "rank": 1},
+        ],
+        total_ms=90_000 + llm_call_count * 1000,
+        step_count=llm_call_count * 3,
+        llm_call_count=llm_call_count,
+        retry_count=retry_count,
+        input_tokens=input_tokens,
+        output_tokens=output_tokens,
+        llm_calls=calls,
+        llm_cost_yuan=cost,
+        llm_price_snapshot=snapshot,
+        created_at=created_at,
+    )
+    return rec, cost
+
+
+def seed(db) -> list[tuple[str, float | None]]:
+    app_config.set_value(db, "llm_token_price", PRICE_CFG, admin_id=None)  # upsert 单价
+    owner_id = db.execute(select(User.id).order_by(User.id).limit(1)).scalar()
+    base = _naive_bj_now()
+    out: list[tuple[str, float | None]] = []
+    for i, spec in enumerate(RECORDS):
+        rec, cost = _build_record(spec, owner_id, base - timedelta(minutes=i * 3))
+        db.add(rec)
+        out.append((spec["label"], cost))
+    db.commit()
+    return out, owner_id
+
+
+def main() -> None:
+    parser = argparse.ArgumentParser(description="造带 LLM 成本的比价记录 + app_config 模型单价(测管理后端)")
+    parser.add_argument("--clean-only", action="store_true", help="只清 MOCKLLM- 记录,不重建(保留单价)")
+    args = parser.parse_args()
+
+    db = SessionLocal()
+    try:
+        removed = clean(db)
+        if removed:
+            print(f"🧹 已清理旧 mock 记录 {removed} 条")
+        if args.clean_only:
+            print("✅ 仅清理,已完成(app_config 单价保留)。")
+            return
+
+        results, owner_id = seed(db)
+        print(f"\n✅ 已写入 app_config.llm_token_price(单价)+ {len(results)} 条比价记录"
+              f"(挂 user_id={owner_id or 'NULL(孤儿行)'})")
+        print("\n📋 每条冻结成本(admin 详情「LLM 成本」应显示):")
+        for label, cost in results:
+            shown = "NULL → 前端回退「估算」" if cost is None else f"¥{cost}"
+            print(f"  {label:<20} {shown}")
+        print("\n👉 验收:admin「比价记录」→ trace 搜「MOCKLLM-」→ 点开详情核对 LLM 成本 + 价格快照。")
+        print("   配置页「系统配置」→「福利页」Tab →「LLM 成本」卡片,单价应为「已改」态。")
+    finally:
+        db.close()
+
+
+if __name__ == "__main__":
+    main()

tests/test_llm_cost.py

@@ -0,0 +1,184 @@
+"""LLM 调用成本计算 compute_llm_cost:按模型分桶累加 token × 单价;error/无 usage 跳过。"""
+from __future__ import annotations
+
+from app.services.llm_cost import compute_llm_cost
+
+_PRICE = {
+    "per_model": {"qwen3.5-flash": {"input_per_1m": 0.8, "output_per_1m": 2.0}},
+    "default": {"input_per_1m": 3.0, "output_per_1m": 15.0},
+}
+
+
+def test_sums_per_model_single_model():
+    # 真实样本:4 次 qwen3.5-flash;Σprompt=6888、Σcompletion=337
+    calls = [
+        {"model": "qwen3.5-flash", "error": None, "usage": {"prompt_tokens": 1512, "completion_tokens": 22}},
+        {"model": "qwen3.5-flash", "error": None, "usage": {"prompt_tokens": 2111, "completion_tokens": 160}},
+        {"model": "qwen3.5-flash", "error": None, "usage": {"prompt_tokens": 1940, "completion_tokens": 142}},
+        {"model": "qwen3.5-flash", "error": None, "usage": {"prompt_tokens": 1325, "completion_tokens": 13}},
+    ]
+    cost, snapshot = compute_llm_cost(calls, _PRICE)
+    # 6888/1e6*0.8 + 337/1e6*2.0 = 0.0055104 + 0.000674 = 0.0061844 → round(6)
+    assert cost == 0.006184
+    assert snapshot == {
+        "mode": "per_model",
+        "prices": {
+            "qwen3.5-flash": {"input_per_1m": 0.8, "output_per_1m": 2.0, "_source": "per_model"},
+        },
+    }
+
+
+def test_multi_model_prices_each_bucket_separately():
+    calls = [
+        {"model": "qwen3.5-flash", "error": None, "usage": {"prompt_tokens": 1_000_000, "completion_tokens": 0}},
+        {"model": "gpt-x", "error": None, "usage": {"prompt_tokens": 0, "completion_tokens": 1_000_000}},
+    ]
+    price = {
+        "per_model": {
+            "qwen3.5-flash": {"input_per_1m": 0.8, "output_per_1m": 2.0},
+            "gpt-x": {"input_per_1m": 10.0, "output_per_1m": 30.0},
+        },
+        "default": {"input_per_1m": 3.0, "output_per_1m": 15.0},
+    }
+    cost, snap = compute_llm_cost(calls, price)
+    assert cost == 30.8  # qwen 1M入×0.8=0.8 + gpt-x 1M出×30=30.0
+    assert set(snap["prices"]) == {"qwen3.5-flash", "gpt-x"}
+
+
+def test_unknown_model_falls_back_to_default():
+    calls = [{"model": "mystery", "error": None, "usage": {"prompt_tokens": 1_000_000, "completion_tokens": 0}}]
+    price = {"per_model": {}, "default": {"input_per_1m": 3.0, "output_per_1m": 15.0}}
+    cost, snap = compute_llm_cost(calls, price)
+    assert cost == 3.0
+    assert snap["prices"]["mystery"]["_source"] == "default"
+
+
+def test_unpriced_model_marked_and_zero_cost():
+    calls = [{"model": "mystery", "error": None, "usage": {"prompt_tokens": 1_000_000, "completion_tokens": 999}}]
+    cost, snap = compute_llm_cost(calls, {"per_model": {}})  # 无 default
+    assert cost == 0.0
+    assert snap["prices"]["mystery"]["unpriced"] is True
+
+
+def test_error_and_missing_usage_calls_skipped():
+    calls = [
+        {"model": "qwen3.5-flash", "error": "boom", "usage": {"prompt_tokens": 9_999_999, "completion_tokens": 9_999_999}},
+        {"model": "qwen3.5-flash", "error": None, "usage": None},  # 无 usage
+        {"model": "qwen3.5-flash", "error": None, "usage": {"prompt_tokens": 1_000_000, "completion_tokens": 0}},
+    ]
+    cost, _ = compute_llm_cost(calls, _PRICE)
+    assert cost == 0.8  # 只有第 3 条计入
+
+
+def test_empty_or_all_error_returns_none():
+    assert compute_llm_cost([], _PRICE) == (None, None)
+    assert compute_llm_cost(None, _PRICE) == (None, None)
+    all_error = [{"model": "x", "error": "boom", "usage": {"prompt_tokens": 100, "completion_tokens": 100}}]
+    assert compute_llm_cost(all_error, _PRICE) == (None, None)
+
+
+def test_malformed_price_entry_is_treated_as_unpriced_not_raised():
+    # 手改配置页可能存出残缺/非法单价(缺 output_per_1m、非 dict);不能抛异常连累 token 回填。
+    calls = [
+        {"model": "bad-a", "error": None, "usage": {"prompt_tokens": 1_000_000, "completion_tokens": 5}},
+        {"model": "bad-b", "error": None, "usage": {"prompt_tokens": 1_000_000, "completion_tokens": 5}},
+        {"model": "ok", "error": None, "usage": {"prompt_tokens": 1_000_000, "completion_tokens": 0}},
+    ]
+    price = {
+        "per_model": {
+            "bad-a": {"input_per_1m": 0.8},   # 缺 output_per_1m
+            "bad-b": 5,                        # 非 dict
+            "ok": {"input_per_1m": 3.0, "output_per_1m": 15.0},
+        },
+    }
+    cost, snap = compute_llm_cost(calls, price)  # 不得抛异常
+    assert cost == 3.0  # 只有 ok(1M 入 × 3.0)计入;两个残缺项按 unpriced
+    assert snap["prices"]["bad-a"].get("unpriced") is True
+    assert snap["prices"]["bad-b"].get("unpriced") is True
+
+
+def test_get_llm_prices_falls_back_to_default_then_uses_override():
+    from app.db.session import SessionLocal
+    from app.models.app_config import AppConfig
+    from app.repositories import app_config
+    from app.services.llm_cost import get_llm_prices
+
+    db = SessionLocal()
+    try:
+        # 无 override → CONFIG_DEFS 默认(含 per_model / default)
+        prices = get_llm_prices(db)
+        assert "per_model" in prices and "default" in prices
+        # 有 override → 用 DB 值
+        app_config.set_value(
+            db, "llm_token_price",
+            {"per_model": {"m": {"input_per_1m": 1.0, "output_per_1m": 2.0}},
+             "default": {"input_per_1m": 0.0, "output_per_1m": 0.0}},
+            admin_id=1,
+        )
+        assert get_llm_prices(db)["per_model"]["m"]["input_per_1m"] == 1.0
+    finally:
+        row = db.get(AppConfig, "llm_token_price")
+        if row is not None:
+            db.delete(row)
+            db.commit()
+        db.close()
+
+
+def test_backfill_llm_calls_stores_cost_and_snapshot(monkeypatch):
+    from datetime import UTC, datetime
+
+    from app.api.v1 import compare_record
+    from app.db.session import SessionLocal
+    from app.models.app_config import AppConfig
+    from app.models.comparison import ComparisonRecord
+    from app.repositories import app_config
+
+    sample = [
+        {"model": "qwen3.5-flash", "error": None, "usage": {"prompt_tokens": 1512, "completion_tokens": 22}},
+        {"model": "qwen3.5-flash", "error": None, "usage": {"prompt_tokens": 2111, "completion_tokens": 160}},
+        {"model": "qwen3.5-flash", "error": None, "usage": {"prompt_tokens": 1940, "completion_tokens": 142}},
+        {"model": "qwen3.5-flash", "error": None, "usage": {"prompt_tokens": 1325, "completion_tokens": 13}},
+    ]
+    monkeypatch.setattr(compare_record, "fetch_llm_calls", lambda trace_id: sample)
+
+    db = SessionLocal()
+    try:
+        app_config.set_value(
+            db, "llm_token_price",
+            {"per_model": {"qwen3.5-flash": {"input_per_1m": 0.8, "output_per_1m": 2.0}},
+             "default": {"input_per_1m": 3.0, "output_per_1m": 15.0}},
+            admin_id=1,
+        )
+        rec = ComparisonRecord(
+            trace_id="llmcost-bf-1", status="success",
+            created_at=datetime.now(UTC).replace(tzinfo=None),
+        )
+        db.add(rec)
+        db.commit()
+        rid = rec.id
+    finally:
+        db.close()
+
+    compare_record._backfill_llm_calls(rid, "llmcost-bf-1")  # 独立 session 内回填
+
+    db = SessionLocal()
+    try:
+        rec = db.get(ComparisonRecord, rid)
+        assert rec.llm_cost_yuan == 0.006184
+        assert rec.llm_price_snapshot["prices"]["qwen3.5-flash"]["input_per_1m"] == 0.8
+        assert rec.input_tokens == 6888  # 现有 token 派生仍在
+    finally:
+        db.delete(db.get(ComparisonRecord, rid))
+        row = db.get(AppConfig, "llm_token_price")
+        if row is not None:
+            db.delete(row)
+        db.commit()
+        db.close()
+
+
+def test_admin_detail_schema_exposes_llm_cost_fields():
+    from app.admin.schemas.comparison import AdminComparisonDetail
+
+    fields = AdminComparisonDetail.model_fields
+    assert "llm_cost_yuan" in fields
+    assert "llm_price_snapshot" in fields

tests/test_wechat_conflict.py

@@ -0,0 +1,211 @@
+"""微信登录 M2 测试:conflict_ticket 令牌、继续绑定(attach/只登入)、换绑(建号+软删+30天限)。
+
+沿用 tests/test_wechat_login.py 风格:HTTP 走 client;微信 code→openid 用 monkeypatch;
+短信走 SMS_MOCK(任意 6 位过)。数据变更用"再走一遍 wechat-login 看 openid 落在哪个账号"做行为断言。
+"""
+from __future__ import annotations
+
+import pytest
+
+from app.api.v1 import auth  # noqa: F401  (后续测试打桩 verify_and_get_phone 用)
+from app.core import security
+from app.integrations import wxpay
+from app.models.phone_rebind_log import PhoneRebindLog
+
+
+def _fake_userinfo(openid: str, nickname: str | None = "微信昵称", avatar: str | None = "http://x/a.png"):
+    def _f(code: str) -> dict:
+        return {"openid": openid, "nickname": nickname, "avatar_url": avatar, "raw": {}}
+    return _f
+
+
+def _sms_occupy(client, phone: str) -> int:
+    """用普通短信登录占用一个手机号(register_channel=sms),返回该账号 id。"""
+    assert client.post("/api/v1/auth/sms/send", json={"phone": phone}).status_code == 200
+    r = client.post("/api/v1/auth/sms/login", json={"phone": phone, "code": "123456"})
+    assert r.status_code == 200, r.text
+    return r.json()["user"]["id"]
+
+
+def _occupy_via_conflict(client, monkeypatch, openid: str, phone: str, device_id: str) -> dict:
+    """微信登录(新 openid)→ 绑同一手机号 → 返回 phone_occupied 的响应体(含 conflict_ticket)。"""
+    monkeypatch.setattr(wxpay, "code_to_userinfo", _fake_userinfo(openid))
+    ticket = client.post(
+        "/api/v1/auth/wechat-login", json={"code": "c", "device_id": device_id}
+    ).json()["bind_ticket"]
+    r = client.post(
+        "/api/v1/auth/wechat/bind-phone/sms",
+        json={"bind_ticket": ticket, "phone": phone, "code": "123456", "device_id": device_id},
+    )
+    assert r.status_code == 200, r.text
+    body = r.json()
+    assert body["status"] == "phone_occupied"
+    return body
+
+
+# ===== Task 1: 模型可导入(建表由 conftest 的 create_all 完成) =====
+
+def test_phone_rebind_log_model_importable() -> None:
+    assert PhoneRebindLog.__tablename__ == "phone_rebind_log"
+
+
+# ===== Task 2: conflict_ticket 令牌 =====
+
+def test_conflict_ticket_roundtrip() -> None:
+    token = security.create_conflict_ticket(
+        openid="oid1", wechat_nickname="昵", wechat_avatar_url="http://a", phone="13900139000"
+    )
+    claims = security.decode_conflict_ticket(token)
+    assert claims["openid"] == "oid1"
+    assert claims["wnk"] == "昵"
+    assert claims["wav"] == "http://a"
+    assert claims["phone"] == "13900139000"
+
+
+def test_conflict_ticket_wrong_type_rejected() -> None:
+    # bind_ticket 冒充 conflict_ticket → TokenError(typ 不匹配)
+    bind = security.create_bind_ticket(openid="oid", wechat_nickname=None, wechat_avatar_url=None)
+    with pytest.raises(security.TokenError):
+        security.decode_conflict_ticket(bind)
+
+
+def test_conflict_ticket_expired_rejected(monkeypatch) -> None:
+    monkeypatch.setattr(security.settings, "WECHAT_BIND_TICKET_EXPIRE_MINUTES", -1)
+    token = security.create_conflict_ticket(
+        openid="oid", wechat_nickname=None, wechat_avatar_url=None, phone="13900139000"
+    )
+    with pytest.raises(security.TokenError):
+        security.decode_conflict_ticket(token)
+
+
+# ===== Task 3: 占用响应扩展 =====
+
+def test_phone_occupied_returns_conflict_ticket_and_flags(client, monkeypatch) -> None:
+    phone = "13900139101"
+    _sms_occupy(client, phone)  # 老账号 X(sms,无微信)
+    body = _occupy_via_conflict(client, monkeypatch, "openid_occ_101", phone, "devO1")
+    assert body["conflict_ticket"]
+    assert body["rebind_available"] is True      # 首次,未换绑过
+    assert body["rebind_blocked_days"] == 0
+    assert body["occupied_account"]["has_wechat"] is False  # X 是 sms 账号
+
+
+# ===== Task 4: 继续绑定 =====
+
+def test_continue_attaches_wechat_and_logs_into_existing(client, monkeypatch) -> None:
+    """X 无微信 → 继续绑定并入 openid + 登入 X;之后同 openid 登录直接命中 X。"""
+    phone = "13900139201"
+    x_id = _sms_occupy(client, phone)  # X:sms 账号,无微信
+    body = _occupy_via_conflict(client, monkeypatch, "openid_cont_201", phone, "devC1")
+
+    r = client.post(
+        "/api/v1/auth/wechat/conflict/continue",
+        json={"conflict_ticket": body["conflict_ticket"], "device_id": "devC1"},
+    )
+    assert r.status_code == 200, r.text
+    assert r.json()["status"] == "logged_in"
+    assert r.json()["token"]["user"]["id"] == x_id  # 登入的是老账号 X
+
+    # openid 现已并入 X:再走 wechat-login 直接命中 X
+    r = client.post("/api/v1/auth/wechat-login", json={"code": "c", "device_id": "devC1"})
+    assert r.json()["status"] == "logged_in"
+    assert r.json()["token"]["user"]["id"] == x_id
+
+
+def test_continue_when_existing_has_wechat_logs_in_and_discards_openid(client, monkeypatch) -> None:
+    """X 已绑别的微信 → 继续绑定只登入 X、丢弃本次 openid(不覆盖)。"""
+    phone = "13900139202"
+    # 先建一个已绑微信 O1 的账号 X(微信登录 O1 + 短信绑号)
+    monkeypatch.setattr(wxpay, "code_to_userinfo", _fake_userinfo("openid_o1_202"))
+    t = client.post("/api/v1/auth/wechat-login", json={"code": "c", "device_id": "devC2"}).json()["bind_ticket"]
+    x = client.post(
+        "/api/v1/auth/wechat/bind-phone/sms",
+        json={"bind_ticket": t, "phone": phone, "code": "123456", "device_id": "devC2"},
+    ).json()
+    x_id = x["token"]["user"]["id"]
+
+    # 新 openid O2 撞同号 → 占用(has_wechat=True)→ 继续绑定
+    body = _occupy_via_conflict(client, monkeypatch, "openid_o2_202", phone, "devC2b")
+    assert body["occupied_account"]["has_wechat"] is True
+    r = client.post(
+        "/api/v1/auth/wechat/conflict/continue",
+        json={"conflict_ticket": body["conflict_ticket"], "device_id": "devC2b"},
+    )
+    assert r.status_code == 200, r.text
+    assert r.json()["token"]["user"]["id"] == x_id  # 登入 X
+
+    # O2 被丢弃:再走 wechat-login(O2)→ 仍未命中(need_bind_phone)
+    monkeypatch.setattr(wxpay, "code_to_userinfo", _fake_userinfo("openid_o2_202"))
+    assert client.post(
+        "/api/v1/auth/wechat-login", json={"code": "c", "device_id": "devC2b"}
+    ).json()["status"] == "need_bind_phone"
+
+
+def test_continue_expired_ticket_returns_401(client, monkeypatch) -> None:
+    monkeypatch.setattr(security.settings, "WECHAT_BIND_TICKET_EXPIRE_MINUTES", -1)
+    expired = security.create_conflict_ticket(
+        openid="oid", wechat_nickname=None, wechat_avatar_url=None, phone="13900139209"
+    )
+    r = client.post(
+        "/api/v1/auth/wechat/conflict/continue",
+        json={"conflict_ticket": expired, "device_id": "devC3"},
+    )
+    assert r.status_code == 401, r.text
+
+
+# ===== Task 5: 换绑 =====
+
+def test_rebind_creates_new_account_and_binds_openid(client, monkeypatch) -> None:
+    """换绑 → 建全新微信账号 Y(≠X)+ openid 落到 Y;老账号 X 被注销(手机号归 Y)。"""
+    phone = "13900139301"
+    x_id = _sms_occupy(client, phone)
+    body = _occupy_via_conflict(client, monkeypatch, "openid_rb_301", phone, "devR1")
+
+    r = client.post(
+        "/api/v1/auth/wechat/conflict/rebind",
+        json={"conflict_ticket": body["conflict_ticket"], "device_id": "devR1"},
+    )
+    assert r.status_code == 200, r.text
+    y = r.json()["token"]["user"]
+    assert r.json()["status"] == "logged_in"
+    assert y["phone"] == phone
+    assert y["register_channel"] == "wechat"
+    assert y["id"] != x_id  # 是全新账号,不是老账号
+
+    # openid 落到 Y:再走 wechat-login 命中 Y
+    r = client.post("/api/v1/auth/wechat-login", json={"code": "c", "device_id": "devR1"})
+    assert r.json()["status"] == "logged_in"
+    assert r.json()["token"]["user"]["id"] == y["id"]
+
+
+def test_rebind_blocked_within_30_days(client, monkeypatch) -> None:
+    """同一手机号 30 天内二次换绑 → 409;占用响应 rebind_available=False。"""
+    phone = "13900139302"
+    _sms_occupy(client, phone)
+    body = _occupy_via_conflict(client, monkeypatch, "openid_rb_302a", phone, "devR2")
+    assert client.post(
+        "/api/v1/auth/wechat/conflict/rebind",
+        json={"conflict_ticket": body["conflict_ticket"], "device_id": "devR2"},
+    ).status_code == 200
+
+    # 第二次:新 openid 撞同号 → 占用响应此时 rebind_available=False
+    body2 = _occupy_via_conflict(client, monkeypatch, "openid_rb_302b", phone, "devR2b")
+    assert body2["rebind_available"] is False
+    assert body2["rebind_blocked_days"] >= 1
+    r = client.post(
+        "/api/v1/auth/wechat/conflict/rebind",
+        json={"conflict_ticket": body2["conflict_ticket"], "device_id": "devR2b"},
+    )
+    assert r.status_code == 409, r.text
+
+
+def test_rebind_expired_ticket_returns_401(client, monkeypatch) -> None:
+    monkeypatch.setattr(security.settings, "WECHAT_BIND_TICKET_EXPIRE_MINUTES", -1)
+    expired = security.create_conflict_ticket(
+        openid="oid", wechat_nickname=None, wechat_avatar_url=None, phone="13900139309"
+    )
+    r = client.post(
+        "/api/v1/auth/wechat/conflict/rebind",
+        json={"conflict_ticket": expired, "device_id": "devR3"},
+    )
+    assert r.status_code == 401, r.text