from typing import List, Optional

from fastapi import APIRouter, Depends, HTTPException, status
from sqlalchemy import or_
from sqlalchemy.orm import Session

from app.core.bx_auth import BxUserContext, get_bx_current_user
from app.core.database import get_db
from app.core.tenant_context import get_tenant_no
from app.models.bx_models import BxAdvanceApply, BxWorkflowDef
from app.schemas.bx.advance import (
    AdvanceApplyCreate,
    AdvanceApplyOut,
    AdvanceApplyUpdate,
    AdvanceApprovalCreate,
    AdvanceApprovalOut,
    AdvanceApproverPendingStatsOut,
    AdvanceMyStatsOut,
)
from app.schemas.bx.common import ApiResponse, PagedData
from app.services.bx.advance import AdvanceService
from app.services.bx.expense_item import ExpenseItemService
from app.utils.bx_codegen import generate_apply_code
from app.utils.bx_date_range import append_create_time_filters

router = APIRouter(prefix="/advances", tags=["备用金管理"])


def _tenant(db: Session, user: BxUserContext) -> str:
    return get_tenant_no(db, user.to_tenant_user_dict())


def _fill_offset_amounts(db: Session, tenant_no: str, rows, out_rows: List[AdvanceApplyOut]) -> None:
    if not out_rows:
        return
    offset_map = AdvanceService.offset_amount_map(db, tenant_no, [r.id for r in rows])
    for out_row in out_rows:
        out_row.offset_amount = offset_map.get(out_row.id, 0.0)


@router.get("/", response_model=ApiResponse[PagedData[AdvanceApplyOut]])
def list_advances(
    page: int = 1,
    pageSize: int = 10,
    status: Optional[str] = None,
    keyword: str = "",
    applicantId: Optional[str] = None,
    applyDate: Optional[str] = None,
    applyDateFrom: Optional[str] = None,
    applyDateTo: Optional[str] = None,
    db: Session = Depends(get_db),
    user: BxUserContext = Depends(get_bx_current_user),
):
    tenant_no = _tenant(db, user)
    filters = []
    if status:
        filters.append(BxAdvanceApply.status == status)
    if keyword:
        filters.append(
            or_(
                BxAdvanceApply.apply_code.contains(keyword),
                BxAdvanceApply.applicant_name.contains(keyword),
            )
        )
    if applicantId:
        filters.append(BxAdvanceApply.applicant_id == str(applicantId).strip())
    append_create_time_filters(
        filters,
        BxAdvanceApply,
        apply_date=applyDate,
        apply_date_from=applyDateFrom,
        apply_date_to=applyDateTo,
    )
    rows, total = AdvanceService.get_paged(db, tenant_no, page=page, page_size=pageSize, filters=filters, user=user)
    out_rows = [AdvanceApplyOut.model_validate(r) for r in rows]
    _fill_offset_amounts(db, tenant_no, rows, out_rows)
    return ApiResponse(data=PagedData(rows=out_rows, total=total, page=page, page_size=pageSize))


@router.get("/my", response_model=ApiResponse[PagedData[AdvanceApplyOut]])
def my_advances(
    page: int = 1,
    pageSize: int = 10,
    status: Optional[str] = None,
    keyword: str = "",
    applyDate: Optional[str] = None,
    applyDateFrom: Optional[str] = None,
    applyDateTo: Optional[str] = None,
    db: Session = Depends(get_db),
    user: BxUserContext = Depends(get_bx_current_user),
):
    tenant_no = _tenant(db, user)
    filters = [
        or_(
            BxAdvanceApply.applicant_id == user.id,
            BxAdvanceApply.create_by == user.id,
        )
    ]
    if status:
        filters.append(BxAdvanceApply.status == status)
    if keyword:
        filters.append(
            or_(
                BxAdvanceApply.apply_code.contains(keyword),
                BxAdvanceApply.applicant_name.contains(keyword),
            )
        )
    append_create_time_filters(
        filters,
        BxAdvanceApply,
        apply_date=applyDate,
        apply_date_from=applyDateFrom,
        apply_date_to=applyDateTo,
    )
    rows, total = AdvanceService.get_paged(db, tenant_no, page=page, page_size=pageSize, filters=filters, user=user)
    out_rows = [AdvanceApplyOut.model_validate(r) for r in rows]
    _fill_offset_amounts(db, tenant_no, rows, out_rows)
    return ApiResponse(data=PagedData(rows=out_rows, total=total, page=page, page_size=pageSize))


@router.get("/my/stats", response_model=ApiResponse[AdvanceMyStatsOut])
def my_advance_stats(
    db: Session = Depends(get_db),
    user: BxUserContext = Depends(get_bx_current_user),
):
    tenant_no = _tenant(db, user)
    data = AdvanceService.my_apply_stats(db, user, tenant_no)
    return ApiResponse(data=AdvanceMyStatsOut.model_validate(data))


@router.get("/stats/status-counts", response_model=ApiResponse[dict])
def advance_status_counts(
    db: Session = Depends(get_db),
    user: BxUserContext = Depends(get_bx_current_user),
):
    tenant_no = _tenant(db, user)
    return ApiResponse(data=AdvanceService.global_status_counts(db, tenant_no, user=user))


@router.get("/pending-approval", response_model=ApiResponse[PagedData[AdvanceApplyOut]])
def pending_approval(
    page: int = 1,
    pageSize: int = 10,
    keyword: str = "",
    applicantId: Optional[str] = None,
    applyDate: Optional[str] = None,
    applyDateFrom: Optional[str] = None,
    applyDateTo: Optional[str] = None,
    db: Session = Depends(get_db),
    user: BxUserContext = Depends(get_bx_current_user),
):
    tenant_no = _tenant(db, user)
    applicant_id = str(applicantId).strip() if applicantId else None
    rows, total = AdvanceService.pending_approval(
        db,
        user,
        tenant_no,
        page=page,
        page_size=pageSize,
        keyword=keyword,
        applicant_id=applicant_id,
        apply_date=applyDate,
        apply_date_from=applyDateFrom,
        apply_date_to=applyDateTo,
    )
    out_rows = [AdvanceApplyOut.model_validate(r) for r in rows]
    return ApiResponse(data=PagedData(rows=out_rows, total=total, page=page, page_size=pageSize))


@router.get("/pending-approval/stats", response_model=ApiResponse[AdvanceApproverPendingStatsOut])
def advance_pending_approval_stats(
    db: Session = Depends(get_db),
    user: BxUserContext = Depends(get_bx_current_user),
):
    tenant_no = _tenant(db, user)
    data = AdvanceService.pending_approval_stats(db, user, tenant_no)
    return ApiResponse(data=AdvanceApproverPendingStatsOut.model_validate(data))


@router.get("/approved-by-me", response_model=ApiResponse[PagedData[AdvanceApplyOut]])
def approved_by_me(
    page: int = 1,
    pageSize: int = 10,
    keyword: str = "",
    applicantId: Optional[str] = None,
    applyDate: Optional[str] = None,
    applyDateFrom: Optional[str] = None,
    applyDateTo: Optional[str] = None,
    db: Session = Depends(get_db),
    user: BxUserContext = Depends(get_bx_current_user),
):
    tenant_no = _tenant(db, user)
    applicant_id = str(applicantId).strip() if applicantId else None
    rows, total = AdvanceService.approved_by_me(
        db,
        user,
        tenant_no,
        page=page,
        page_size=pageSize,
        keyword=keyword,
        applicant_id=applicant_id,
        apply_date=applyDate,
        apply_date_from=applyDateFrom,
        apply_date_to=applyDateTo,
    )
    out_rows = [AdvanceApplyOut.model_validate(r) for r in rows]
    return ApiResponse(data=PagedData(rows=out_rows, total=total, page=page, page_size=pageSize))


@router.get("/{advance_id}", response_model=ApiResponse[AdvanceApplyOut])
def get_advance(
    advance_id: str,
    db: Session = Depends(get_db),
    user: BxUserContext = Depends(get_bx_current_user),
):
    tenant_no = _tenant(db, user)
    advance = AdvanceService.get_by_id(db, advance_id, tenant_no, user=user)
    if not advance:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="备用金申请不存在")
    out = AdvanceApplyOut.model_validate(advance)
    offset_map = AdvanceService.offset_amount_map(db, tenant_no, [advance_id])
    out.offset_amount = offset_map.get(advance_id, 0.0)
    return ApiResponse(data=out)


@router.get("/{advance_id}/approvals", response_model=ApiResponse[List[AdvanceApprovalOut]])
def get_approvals(
    advance_id: str,
    db: Session = Depends(get_db),
    user: BxUserContext = Depends(get_bx_current_user),
):
    tenant_no = _tenant(db, user)
    if not AdvanceService.get_by_id(db, advance_id, tenant_no, user=user):
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="备用金申请不存在")
    approvals = AdvanceService.get_approvals(db, advance_id, tenant_no, user=user)
    return ApiResponse(data=[AdvanceApprovalOut.model_validate(a) for a in approvals])


@router.get("/{advance_id}/approval-history", response_model=ApiResponse[List[AdvanceApprovalOut]])
def get_approval_history(
    advance_id: str,
    db: Session = Depends(get_db),
    user: BxUserContext = Depends(get_bx_current_user),
):
    tenant_no = _tenant(db, user)
    if not AdvanceService.get_by_id(db, advance_id, tenant_no, user=user):
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="备用金申请不存在")
    history = AdvanceService.get_approval_history(db, advance_id, tenant_no, user=user)
    return ApiResponse(data=[AdvanceApprovalOut.model_validate(a) for a in history])


@router.post("/", response_model=ApiResponse[AdvanceApplyOut])
def create_advance(
    body: AdvanceApplyCreate,
    db: Session = Depends(get_db),
    user: BxUserContext = Depends(get_bx_current_user),
):
    tenant_no = _tenant(db, user)
    data = body.model_dump(exclude_unset=True)
    eid = data.get("expense_item_id")
    if eid:
        if not ExpenseItemService.get_by_id(db, eid, tenant_no, user=user, skip_scope=True):
            raise HTTPException(status_code=status.HTTP_400_BAD_REQUEST, detail=f"费用项目 {eid} 不存在")
    data["applicant_id"] = user.id
    data["applicant_name"] = user.name
    data["apply_code"] = generate_apply_code(db, "BYJ", tenant_no)
    data["status"] = "draft"
    wf = (
        db.query(BxWorkflowDef)
        .filter(
            BxWorkflowDef.biz_type == "advance",
            BxWorkflowDef.tenant_no == tenant_no,
            BxWorkflowDef.del_flag == 0,
        )
        .first()
    )
    if wf:
        data["wf_id"] = wf.id
    advance = AdvanceService.create(db, data, user=user)
    db.commit()
    db.refresh(advance)
    return ApiResponse(data=AdvanceApplyOut.model_validate(advance))


@router.put("/{advance_id}", response_model=ApiResponse[AdvanceApplyOut])
def update_advance(
    advance_id: str,
    body: AdvanceApplyUpdate,
    db: Session = Depends(get_db),
    user: BxUserContext = Depends(get_bx_current_user),
):
    tenant_no = _tenant(db, user)
    data = body.model_dump(exclude_unset=True)
    if data.get("expense_item_id"):
        eid = data["expense_item_id"]
        if not ExpenseItemService.get_by_id(db, eid, tenant_no, user=user, skip_scope=True):
            raise HTTPException(status_code=status.HTTP_400_BAD_REQUEST, detail=f"费用项目 {eid} 不存在")
    advance = AdvanceService.update(db, advance_id, data, user=user)
    if not advance:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="备用金申请不存在")
    db.commit()
    db.refresh(advance)
    return ApiResponse(data=AdvanceApplyOut.model_validate(advance))


@router.post("/{advance_id}/submit", response_model=ApiResponse[AdvanceApplyOut])
def submit_advance(
    advance_id: str,
    db: Session = Depends(get_db),
    user: BxUserContext = Depends(get_bx_current_user),
):
    advance = AdvanceService.submit(db, advance_id, user)
    if not advance:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="备用金申请不存在")
    db.commit()
    db.refresh(advance)
    return ApiResponse(data=AdvanceApplyOut.model_validate(advance))


@router.post("/{advance_id}/approve", response_model=ApiResponse[AdvanceApplyOut])
def approve_advance(
    advance_id: str,
    body: AdvanceApprovalCreate,
    db: Session = Depends(get_db),
    user: BxUserContext = Depends(get_bx_current_user),
):
    advance = AdvanceService.approve(db, advance_id, user, body.approval_opinion or "")
    if not advance:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="备用金申请不存在或无权审批")
    db.commit()
    db.refresh(advance)
    return ApiResponse(data=AdvanceApplyOut.model_validate(advance))


@router.post("/{advance_id}/reject", response_model=ApiResponse[AdvanceApplyOut])
def reject_advance(
    advance_id: str,
    body: AdvanceApprovalCreate,
    db: Session = Depends(get_db),
    user: BxUserContext = Depends(get_bx_current_user),
):
    advance = AdvanceService.reject(db, advance_id, user, body.approval_opinion or "")
    if not advance:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="备用金申请不存在或无权审批")
    db.commit()
    db.refresh(advance)
    return ApiResponse(data=AdvanceApplyOut.model_validate(advance))


@router.delete("/{advance_id}", response_model=ApiResponse[None])
def delete_advance(
    advance_id: str,
    db: Session = Depends(get_db),
    user: BxUserContext = Depends(get_bx_current_user),
):
    tenant_no = _tenant(db, user)
    if not AdvanceService.get_by_id(db, advance_id, tenant_no, user=user):
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="备用金申请不存在")
    AdvanceService.soft_delete(db, advance_id, user=user)
    db.commit()
    return ApiResponse(data=None)