import csv
import io
from datetime import datetime
from typing import Any, List, Optional
from urllib.parse import quote

from fastapi import APIRouter, Depends, HTTPException, status
from fastapi.responses import StreamingResponse
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, BxReimburseApply, BxReimburseOffset
from app.schemas.bx.advance import (
    AdvanceFinanceIssueStatsOut,
    AdvanceIssueOut,
    AdvanceIssueRequest,
    AdvanceOffsetRecordOut,
)
from app.schemas.bx.common import ApiResponse, PagedData
from app.schemas.bx.reimburse import (
    BatchOffsetRequest,
    OffsetRequest,
    PayRequest,
    PaymentFinanceStatsOut,
    ReimburseApplyOut,
    ReimburseOffsetRecordOut,
)
from app.services.bx.advance import AdvanceService
from app.services.bx.attachment import AttachmentService
from app.services.bx.reimburse import ReimburseService
from app.utils.bx_date_range import append_create_time_filters

router = APIRouter(prefix="/payments", tags=["支付处理"])


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


def _wrap_reimburse_rows(outs: List[ReimburseApplyOut]) -> List[dict]:
    return [{"type": "reimburse", "data": o.model_dump(by_alias=True)} for o in outs]


@router.get("/pending", response_model=ApiResponse[PagedData[Any]])
def list_pending_payments(
    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)
    filters = [BxReimburseApply.status == "approved"]
    if keyword:
        filters.append(
            or_(
                BxReimburseApply.apply_code.contains(keyword),
                BxReimburseApply.applicant_name.contains(keyword),
            )
        )
    if applicantId:
        filters.append(BxReimburseApply.applicant_id == str(applicantId).strip())
    append_create_time_filters(
        filters,
        BxReimburseApply,
        apply_date=applyDate,
        apply_date_from=applyDateFrom,
        apply_date_to=applyDateTo,
    )
    rows, total = ReimburseService.get_paged(db, tenant_no, page=page, page_size=pageSize, filters=filters, user=user)
    outs = ReimburseService.out_rows_with_attachment_counts(db, tenant_no, list(rows))
    return ApiResponse(
        data=PagedData(rows=_wrap_reimburse_rows(outs), total=total, page=page, page_size=pageSize)
    )


@router.get("/stats", response_model=ApiResponse[PaymentFinanceStatsOut])
def payment_finance_stats(
    db: Session = Depends(get_db),
    user: BxUserContext = Depends(get_bx_current_user),
):
    tenant_no = _tenant(db, user)
    data = ReimburseService.finance_payment_stats(db, tenant_no, user=user)
    return ApiResponse(data=PaymentFinanceStatsOut.model_validate(data))


@router.get("/processed", response_model=ApiResponse[PagedData[Any]])
def list_processed_payments(
    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)
    filters = [BxReimburseApply.status.in_(["processed", "paid", "offset"])]
    if keyword:
        filters.append(
            or_(
                BxReimburseApply.apply_code.contains(keyword),
                BxReimburseApply.applicant_name.contains(keyword),
            )
        )
    if applicantId:
        filters.append(BxReimburseApply.applicant_id == str(applicantId).strip())
    append_create_time_filters(
        filters,
        BxReimburseApply,
        apply_date=applyDate,
        apply_date_from=applyDateFrom,
        apply_date_to=applyDateTo,
    )
    rows, total = ReimburseService.get_paged(db, tenant_no, page=page, page_size=pageSize, filters=filters, user=user)
    outs = ReimburseService.out_rows_with_attachment_counts(db, tenant_no, list(rows))
    return ApiResponse(
        data=PagedData(rows=_wrap_reimburse_rows(outs), total=total, page=page, page_size=pageSize)
    )


@router.post("/{payment_id}/pay", response_model=ApiResponse[ReimburseApplyOut])
def pay(
    payment_id: str,
    body: Optional[PayRequest] = None,
    db: Session = Depends(get_db),
    user: BxUserContext = Depends(get_bx_current_user),
):
    tenant_no = _tenant(db, user)
    pay_remark = body.pay_remark if body else ""
    actual_amount = body.actual_amount if body else None
    reimburse = ReimburseService.pay(
        db, payment_id, user, pay_remark=pay_remark or "", actual_amount=actual_amount
    )
    if not reimburse:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="支付记录不存在")
    db.commit()
    db.refresh(reimburse)
    return ApiResponse(data=ReimburseService.out_one_with_attachment_counts(db, tenant_no, reimburse))


@router.post("/{payment_id}/offset", response_model=ApiResponse[ReimburseApplyOut])
def offset(
    payment_id: str,
    body: OffsetRequest,
    db: Session = Depends(get_db),
    user: BxUserContext = Depends(get_bx_current_user),
):
    tenant_no = _tenant(db, user)
    reimburse = ReimburseService.offset(
        db,
        payment_id,
        body.advance_id,
        body.offset_amount,
        user,
        remark=body.remark or "",
    )
    if not reimburse:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="支付记录不存在")
    db.commit()
    db.refresh(reimburse)
    return ApiResponse(data=ReimburseService.out_one_with_attachment_counts(db, tenant_no, reimburse))


@router.post("/{payment_id}/batch-offset", response_model=ApiResponse[ReimburseApplyOut])
def batch_offset(
    payment_id: str,
    body: BatchOffsetRequest,
    db: Session = Depends(get_db),
    user: BxUserContext = Depends(get_bx_current_user),
):
    tenant_no = _tenant(db, user)
    reimburse = ReimburseService.batch_offset(
        db,
        payment_id,
        [item.model_dump() for item in body.items],
        body.pay_amount,
        user,
        remark=body.remark or "",
    )
    if not reimburse:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="支付记录不存在")
    db.commit()
    db.refresh(reimburse)
    return ApiResponse(data=ReimburseService.out_one_with_attachment_counts(db, tenant_no, reimburse))


@router.get("/advance-issues", response_model=ApiResponse[PagedData[AdvanceIssueOut]])
def list_advance_issues(
    page: int = 1,
    pageSize: int = 10,
    issue_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 issue_status == "pending":
        filters.append(BxAdvanceApply.status == "approved")
        filters.append(or_(BxAdvanceApply.issue_status.is_(None), BxAdvanceApply.issue_status != "issued"))
    elif issue_status == "issued":
        filters.append(BxAdvanceApply.status == "issued")
    else:
        filters.append(or_(BxAdvanceApply.status == "approved", BxAdvanceApply.status == "issued"))
    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 = [AdvanceIssueOut.model_validate(r) for r in rows]
    if out_rows:
        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)
    return ApiResponse(data=PagedData(rows=out_rows, total=total, page=page, page_size=pageSize))


@router.get("/advance-issues/stats", response_model=ApiResponse[AdvanceFinanceIssueStatsOut])
def advance_issue_stats(
    db: Session = Depends(get_db),
    user: BxUserContext = Depends(get_bx_current_user),
):
    tenant_no = _tenant(db, user)
    data = AdvanceService.finance_issue_stats(db, tenant_no, user=user)
    return ApiResponse(data=AdvanceFinanceIssueStatsOut.model_validate(data))


@router.get("/advance-issues/export")
def export_advance_issues(
    issue_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 issue_status == "pending":
        filters.append(BxAdvanceApply.status == "approved")
        filters.append(or_(BxAdvanceApply.issue_status.is_(None), BxAdvanceApply.issue_status != "issued"))
    elif issue_status == "issued":
        filters.append(BxAdvanceApply.status == "issued")
    else:
        filters.append(or_(BxAdvanceApply.status == "approved", BxAdvanceApply.status == "issued"))
    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, _ = AdvanceService.get_paged(db, tenant_no, page=1, page_size=99999, filters=filters, user=user)
    out_rows = [AdvanceIssueOut.model_validate(r) for r in rows]

    buf = io.StringIO()
    writer = csv.writer(buf)
    writer.writerow(
        [
            "申请单号",
            "申请人",
            "申请原因",
            "申请金额",
            "审批通过时间",
            "发放状态",
            "发放时间",
            "发放操作人",
            "实际发放金额",
            "发放备注",
        ]
    )
    for row in out_rows:
        writer.writerow(
            [
                row.apply_code,
                row.applicant_name,
                row.reason,
                row.amount,
                row.approve_time or "",
                "已发放" if row.issue_status == "issued" else "待发放",
                row.issue_time or "",
                row.issue_user_name or "",
                row.actual_amount or "",
                row.issue_remark or "",
            ]
        )
    buf.seek(0)
    filename = f"备用金发放列表_{datetime.now().strftime('%Y%m%d_%H%M%S')}.csv"
    encoded_name = quote(filename)
    return StreamingResponse(
        iter([buf.getvalue()]),
        media_type="text/csv; charset=utf-8",
        headers={"Content-Disposition": f"attachment; filename*=UTF-8''{encoded_name}"},
    )


@router.post("/advance/{advance_id}/issue", response_model=ApiResponse[AdvanceIssueOut])
def issue_advance(
    advance_id: str,
    body: AdvanceIssueRequest,
    db: Session = Depends(get_db),
    user: BxUserContext = Depends(get_bx_current_user),
):
    tenant_no = _tenant(db, user)
    issue_atts = AttachmentService.get_by_biz(db, "advance_issue", advance_id, tenant_no, user=user)
    if not issue_atts:
        raise HTTPException(status_code=status.HTTP_400_BAD_REQUEST, detail="请至少上传 1 个发放附件")
    advance = AdvanceService.issue(
        db, advance_id, user, body.issue_remark or "", body.actual_amount
    )
    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)
    out = AdvanceIssueOut.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/{advance_id}/offset-records", response_model=ApiResponse[List[AdvanceOffsetRecordOut]])
def list_advance_offset_records(
    advance_id: str,
    db: Session = Depends(get_db),
    user: BxUserContext = Depends(get_bx_current_user),
):
    tenant_no = _tenant(db, user)
    AdvanceService.get_by_id(db, advance_id, tenant_no, user=user)
    rows = (
        db.query(BxReimburseOffset, BxReimburseApply)
        .join(
            BxReimburseApply,
            BxReimburseApply.id == BxReimburseOffset.reimburse_id,
        )
        .filter(
            BxReimburseOffset.advance_id == advance_id,
            BxReimburseOffset.tenant_no == tenant_no,
            BxReimburseOffset.del_flag == 0,
            BxReimburseApply.del_flag == 0,
            BxReimburseApply.tenant_no == tenant_no,
        )
        .order_by(BxReimburseOffset.create_time.desc(), BxReimburseOffset.id.desc())
        .all()
    )
    records = [
        AdvanceOffsetRecordOut(
            reimburse_id=reimburse.id,
            reimburse_apply_code=reimburse.apply_code,
            reimburse_title=reimburse.title,
            reimburse_applicant_name=reimburse.applicant_name,
            offset_amount=float(offset.offset_amount or 0),
            remark=offset.remark,
            operator=offset.create_by,
            create_time=offset.create_time,
        )
        for offset, reimburse in rows
    ]
    return ApiResponse(data=records)


@router.get("/{payment_id}/offset-records", response_model=ApiResponse[List[ReimburseOffsetRecordOut]])
def list_reimburse_offset_records(
    payment_id: str,
    db: Session = Depends(get_db),
    user: BxUserContext = Depends(get_bx_current_user),
):
    tenant_no = _tenant(db, user)
    ReimburseService.get_by_id(db, payment_id, tenant_no, user=user)
    rows = (
        db.query(BxReimburseOffset, BxAdvanceApply)
        .join(BxAdvanceApply, BxAdvanceApply.id == BxReimburseOffset.advance_id)
        .filter(
            BxReimburseOffset.reimburse_id == payment_id,
            BxReimburseOffset.tenant_no == tenant_no,
            BxReimburseOffset.del_flag == 0,
            BxAdvanceApply.del_flag == 0,
            BxAdvanceApply.tenant_no == tenant_no,
        )
        .order_by(BxReimburseOffset.create_time.desc(), BxReimburseOffset.id.desc())
        .all()
    )
    records = [
        ReimburseOffsetRecordOut(
            advance_id=advance.id,
            advance_apply_code=advance.apply_code,
            advance_applicant_name=advance.applicant_name,
            advance_reason=advance.reason,
            offset_amount=float(offset.offset_amount or 0),
            remark=offset.remark,
            operator=offset.create_by,
            create_time=offset.create_time,
        )
        for offset, advance in rows
    ]
    return ApiResponse(data=records)