"""报销单号/标题生成（从 bx-backend 迁移，增加 tenant_no 隔离）。"""
from datetime import datetime

from sqlalchemy import text
from sqlalchemy.orm import Session


def generate_apply_code(db: Session, prefix: str, tenant_no: str) -> str:
    """
    生成顺序单号：{prefix}{YYYYMMDD}{3位序号}。
    prefix 示例：BYJ（备用金）、BX（报销）。
    """
    today = datetime.now().strftime("%Y%m%d")
    like_pattern = f"{prefix}{today}%"

    result = db.execute(
        text(
            "SELECT MAX(CAST(SUBSTRING(apply_code, -3) AS UNSIGNED)) FROM ("
            "SELECT apply_code FROM bx_advance_apply "
            "WHERE tenant_no = :tenant_no AND apply_code LIKE :p1 AND del_flag = 0 "
            "UNION ALL "
            "SELECT apply_code FROM bx_reimburse_apply "
            "WHERE tenant_no = :tenant_no AND apply_code LIKE :p2 AND del_flag = 0"
            ") t"
        ),
        {"tenant_no": tenant_no, "p1": like_pattern, "p2": like_pattern},
    ).scalar()

    seq = (result or 0) + 1
    return f"{prefix}{today}{seq:03d}"


def generate_title(db: Session, applicant_name: str, tenant_no: str) -> str:
    today = datetime.now().strftime("%Y%m%d")
    like_pattern = f"%报销单{today}%"

    result = db.execute(
        text(
            "SELECT COUNT(*) FROM bx_reimburse_apply "
            "WHERE tenant_no = :tenant_no AND title LIKE :p AND del_flag = 0"
        ),
        {"tenant_no": tenant_no, "p": like_pattern},
    ).scalar()

    seq = (result or 0) + 1
    return f"{applicant_name}报销单{today}{seq:03d}"