import uuid

from fastapi import APIRouter, Depends, HTTPException, status
from sqlalchemy.ext.asyncio import AsyncSession

from app.core.deps import get_current_user, get_db_session, require_roles, require_study_member, require_study_roles
from app.crud import study as study_crud
from app.crud import member as member_crud
from app.crud import audit as audit_crud
from app.schemas.common import PaginatedResponse
from app.schemas.study import StudyCreate, StudyRead, StudyUpdate
from app.schemas.member import StudyMemberCreate
from app.utils.pagination import paginate

router = APIRouter()


@router.post("/", response_model=StudyRead, status_code=status.HTTP_201_CREATED, dependencies=[Depends(require_roles(["ADMIN"]))])
async def create_study(
    study_in: StudyCreate,
    db: AsyncSession = Depends(get_db_session),
    current_user=Depends(get_current_user),
) -> StudyRead:
    existing = await study_crud.get_by_code(db, study_in.code)
    if existing:
        raise HTTPException(status_code=status.HTTP_409_CONFLICT, detail="项目编号已存在")
    study = await study_crud.create(db, study_in, created_by=current_user.id)
    
    # 自动将创建者添加为项目成员，角色为PM
    member_in = StudyMemberCreate(
        user_id=current_user.id,
        role_in_study="PM",
        is_active=True,
    )
    await member_crud.add_member(db, study.id, member_in)
    
    return study


@router.get("/", response_model=PaginatedResponse[StudyRead])
async def list_studies(
    skip: int = 0,
    limit: int = 100,
    db: AsyncSession = Depends(get_db_session),
    current_user=Depends(get_current_user),
) -> PaginatedResponse[StudyRead]:
    if current_user.role == "ADMIN":
        studies = await study_crud.list_studies(db, skip=skip, limit=limit)
        total = await study_crud.list_studies(db, skip=0, limit=10_000_000)
    else:
        studies = await study_crud.list_studies_for_user(db, current_user.id, skip=skip, limit=limit)
        total = await study_crud.list_studies_for_user(db, current_user.id, skip=0, limit=10_000_000)
    return paginate(list(studies), total=len(total))


@router.get("/{study_id}", response_model=StudyRead, dependencies=[Depends(require_study_member())])
async def get_study(
    study_id: uuid.UUID,
    db: AsyncSession = Depends(get_db_session),
) -> StudyRead:
    study = await study_crud.get(db, study_id)
    if not study:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="项目不存在")
    return study


@router.patch(
    "/{study_id}",
    response_model=StudyRead,
    dependencies=[Depends(require_study_roles(["PM"]))],
)
async def update_study(
    study_id: uuid.UUID,
    study_in: StudyUpdate,
    db: AsyncSession = Depends(get_db_session),
) -> StudyRead:
    study = await study_crud.get(db, study_id)
    if not study:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="项目不存在")
    
    # 检查项目是否已锁定（除非是解锁操作）
    if study.is_locked and not (study_in.is_locked is False):
        raise HTTPException(
            status_code=status.HTTP_403_FORBIDDEN,
            detail="项目已锁定，无法编辑。请先解锁项目。"
        )
    
    updated = await study_crud.update(db, study, study_in)
    return updated


@router.delete(
    "/{study_id}",
    status_code=status.HTTP_204_NO_CONTENT,
    dependencies=[Depends(require_roles(["ADMIN"]))],
)
async def delete_study(
    study_id: uuid.UUID,
    db: AsyncSession = Depends(get_db_session),
    current_user=Depends(get_current_user),
) -> None:
    """硬删除项目及其所有关联数据（不可逆操作）"""
    study = await study_crud.get(db, study_id)
    if not study:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="项目不存在")
    
    # 删除项目及其所有关联数据（包括审计日志）
    await study_crud.delete(db, study_id)


@router.patch(
    "/{study_id}/lock",
    response_model=StudyRead,
    dependencies=[Depends(require_roles(["ADMIN"]))],
)
async def lock_study(
    study_id: uuid.UUID,
    db: AsyncSession = Depends(get_db_session),
    current_user=Depends(get_current_user),
) -> StudyRead:
    """锁定项目（仅管理员）"""
    study = await study_crud.get(db, study_id)
    if not study:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="项目不存在")
    
    locked_study = await study_crud.lock(db, study_id)
    
    # 记录审计日志
    await audit_crud.log_action(
        db,
        study_id=study_id,
        entity_type="study",
        entity_id=study_id,
        action="LOCK_STUDY",
        detail=f"项目已锁定：{study.name} ({study.code})",
        operator_id=current_user.id,
        operator_role=current_user.role,
    )
    
    return locked_study


@router.patch(
    "/{study_id}/unlock",
    response_model=StudyRead,
    dependencies=[Depends(require_roles(["ADMIN"]))],
)
async def unlock_study(
    study_id: uuid.UUID,
    db: AsyncSession = Depends(get_db_session),
    current_user=Depends(get_current_user),
) -> StudyRead:
    """解锁项目（仅管理员）"""
    study = await study_crud.get(db, study_id)
    if not study:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="项目不存在")
    
    unlocked_study = await study_crud.unlock(db, study_id)
    
    # 记录审计日志
    await audit_crud.log_action(
        db,
        study_id=study_id,
        entity_type="study",
        entity_id=study_id,
        action="UNLOCK_STUDY",
        detail=f"项目已解锁：{study.name} ({study.code})",
        operator_id=current_user.id,
        operator_role=current_user.role,
    )
    
    return unlocked_study