# 合同班次：领取表 3 → 按供应商、货主和三个日期合单 → runner 录合同 → 写表 4。
#
# 崩在 process_status=3：超过租约可再领，未过期需改回 0。
# 未捕获异常原因列只写 PAGE_FAILED。原文进审计表，会话结束后另写。

from __future__ import annotations

import logging
from contextlib import nullcontext
from dataclasses import dataclass
from typing import Callable

from contract_draft import ContractDraft
from errors import DiligenceError, NodeError
from group import draft_from_group, group_by_supplier, missing_mdm_reason
from persist import KIND_DILIGENCE, KIND_FAIL, KIND_OK, ContractOutcome, build_save
from rpa_oracle import ShiftError

PAGE_FAILED = "PAGE_FAILED"
Runner = Callable[[ContractDraft], ContractOutcome]
logger = logging.getLogger("rpa_contract")


# 一个合同班次的领取、合单和成败计数。
@dataclass
class JobSummary:
    claimed: int = 0
    groups: int = 0
    ok: int = 0
    failed: int = 0


def _session(repo):
    """有 session 就借一条，没有就空上下文。页面调用必须在这个块外面。"""
    session = getattr(repo, "session", None)
    if session is None:
        return nullcontext()
    return session()


def run_batch(repo, *, runner: Runner, limit: int | None = None) -> JobSummary:
    """领取待录合同行，按供应商合单、调 runner、落表。

    session 只包领取和每一组的落表。页面在连接归还之后跑。一组落完再处理下一组。
    limit 交给领取层。
    """
    audits: list[ShiftError] = []
    with _session(repo):
        claimed = repo.claim_pending(limit=limit)
    summary = JobSummary(claimed=len(claimed), groups=0)
    for rows in group_by_supplier(claimed):
        summary.groups += 1
        outcome = _run_group(rows, runner)
        with _session(repo):
            repo.save_group(build_save(rows, outcome))
        if outcome.error_text:
            supplier = rows[0].supplier_id if rows else ""
            audits.append(ShiftError("合同", str(supplier), PAGE_FAILED, outcome.error_text))
        if outcome.kind == KIND_OK and (outcome.contract_no or "").strip():
            summary.ok += 1
        else:
            summary.failed += 1
    repo.save_shift_errors(audits)
    return summary


# 录一组同一供应商的行。缺 MDM 不调页面；未捕获异常写 PAGE_FAILED。
def _run_group(rows, runner: Runner) -> ContractOutcome:
    reason = missing_mdm_reason(rows)
    if reason:
        return ContractOutcome(KIND_FAIL, None, reason)
    try:
        outcome = runner(draft_from_group(rows))
    except DiligenceError:
        return ContractOutcome(KIND_DILIGENCE, None, "客户未尽调")
    except NodeError as exc:
        return ContractOutcome(KIND_FAIL, None, str(exc))
    except Exception as exc:
        logger.exception("合同录入未捕获异常 supplier=%s", rows[0].supplier_id if rows else "")
        return ContractOutcome(KIND_FAIL, None, PAGE_FAILED, _text(exc))
    if outcome.kind == KIND_OK and not (outcome.contract_no or "").strip():
        return ContractOutcome(KIND_FAIL, None, "submit 模式未读取到真实合同编号")
    return outcome


# 把页面 run() 的合同号或异常收成 ContractOutcome。
#
# 尽调失败写客户未尽调；NodeError 写业务文案；其它异常写 PAGE_FAILED，原文放 error_text。
def outcome_from_run(run: Callable[[], str]) -> ContractOutcome:
    try:
        number = (run() or "").strip()
    except DiligenceError:
        return ContractOutcome(KIND_DILIGENCE, None, "客户未尽调")
    except NodeError as exc:
        return ContractOutcome(KIND_FAIL, None, str(exc))
    except Exception as exc:
        logger.exception("合同页面未捕获异常")
        return ContractOutcome(KIND_FAIL, None, PAGE_FAILED, _text(exc))
    if not number:
        return ContractOutcome(KIND_FAIL, None, "submit 模式未读取到真实合同编号")
    return ContractOutcome(KIND_OK, number, None)


# 取出异常原文。空串不当审计正文。
def _text(exc: BaseException) -> str | None:
    text = str(exc).strip()
    return text or None