HEL-176: 公司端转账往来明细筛选与导出

新增 events 组合筛选 + keyset 分页，以及仅导出已确认明细的 CSV（含审计）；
与 B-44 ledger /events 按查询参数分发，不改库表与确认语义。

Co-authored-by: Cursor <cursoragent@cursor.com>
Co-authored-by: multica-agent <github@multica.ai>

server.py

@@ -155,10 +155,13 @@ class AppHandler(SimpleHTTPRequestHandler):
             self._handle_admin_intercompany_evidence(int(admin_evidence.group(1)))
             return
 
-        # Company transfer-summary (HEL-169/HEL-175, eligible_intercompany_events)
+        # Company transfer-summary (HEL-169/HEL-175/HEL-176)
         if path == "/api/company/intercompany/summary":
             self._handle_company_intercompany_summary(query)
             return
+        if path == "/api/company/intercompany/export.csv":
+            self._handle_company_intercompany_export_csv(query)
+            return
 
         # B-44 intercompany positions (company, own-company scope)
         if path == "/api/company/intercompany/balances":
@@ -169,6 +172,11 @@ class AppHandler(SimpleHTTPRequestHandler):
             self._handle_company_intercompany_pair(int(company_pair.group(1)), query)
             return
         if path == "/api/company/intercompany/events":
+            # HEL-176 transfer-detail list shares this path with B-44 ledger
+            # events; dispatch by distinctive query params (to/direction/…).
+            if company_transfers.is_transfer_summary_events_query(query):
+                self._handle_company_transfer_summary_events(query)
+            else:
                 self._handle_company_intercompany_events(query)
             return
         if path == "/api/company/manual-records":
@@ -2889,6 +2897,111 @@ class AppHandler(SimpleHTTPRequestHandler):
         finally:
             connection.close()
 
+    def _reject_forged_company_id(self, query: dict[str, list[str]]) -> bool:
+        """Return True when the handler already sent a 400 for company_id."""
+        if (query.get("company_id") or [None])[0] is not None:
+            self._send_json(
+                400,
+                {"status": "error", "message": "不允许传入 company_id 参数。"},
+            )
+            return True
+        return False
+
+    def _handle_company_transfer_summary_events(
+        self, query: dict[str, list[str]]
+    ) -> None:
+        """HEL-176 filtered transfer-detail list (keyset pagination)."""
+        connection = connect(DB_PATH)
+        try:
+            user, company_id = self._company_intercompany_scope(connection)
+            if company_id is None:
+                return
+            if self._reject_forged_company_id(query):
+                return
+            try:
+                payload = company_transfers.company_intercompany_events(
+                    connection,
+                    company_id=int(company_id),
+                    from_=(query.get("from") or [None])[0],
+                    to=(query.get("to") or [None])[0],
+                    counterparty_id=(query.get("counterparty_id") or [None])[0],
+                    direction=(query.get("direction") or [None])[0],
+                    state=(query.get("state") or [None])[0],
+                    limit=(query.get("limit") or [None])[0],
+                    cursor=(query.get("cursor") or [None])[0],
+                )
+            except company_transfers.TransferSummaryInputError as exc:
+                self._send_json(400, {"status": "error", "message": str(exc)})
+                return
+            self._send_json(200, {"status": "ok", **payload})
+        finally:
+            connection.close()
+
+    def _handle_company_intercompany_export_csv(
+        self, query: dict[str, list[str]]
+    ) -> None:
+        """Confirmed-only CSV export; session company scope + audit (HEL-176)."""
+        connection = connect(DB_PATH)
+        try:
+            user, company_id = self._company_intercompany_scope(connection)
+            if company_id is None:
+                return
+            if self._reject_forged_company_id(query):
+                return
+            # Pending must never leave via export, even if a client sends state=.
+            if (query.get("state") or [None])[0] not in (None, "", "confirmed"):
+                self._send_json(
+                    400,
+                    {
+                        "status": "error",
+                        "message": "导出仅支持已确认明细，不允许导出待确认。",
+                    },
+                )
+                return
+            try:
+                items, meta = company_transfers.company_intercompany_export_rows(
+                    connection,
+                    company_id=int(company_id),
+                    from_=(query.get("from") or [None])[0],
+                    to=(query.get("to") or [None])[0],
+                    counterparty_id=(query.get("counterparty_id") or [None])[0],
+                    direction=(query.get("direction") or [None])[0],
+                )
+            except company_transfers.TransferSummaryInputError as exc:
+                self._send_json(400, {"status": "error", "message": str(exc)})
+                return
+            content = company_transfers.render_intercompany_export_csv(items)
+            detail_parts = [
+                f"rows:{meta['row_count']}",
+                f"from:{meta['start']}",
+                f"to:{meta['end']}",
+                "state:confirmed",
+            ]
+            if meta["counterparty_id"] is not None:
+                detail_parts.append(f"counterparty_id:{meta['counterparty_id']}")
+            if meta["direction"] is not None:
+                detail_parts.append(f"direction:{meta['direction']}")
+            auth.audit(
+                connection,
+                "export_intercompany_csv",
+                actor=user,
+                target=f"company:{company_id}",
+                detail=";".join(detail_parts),
+                ip=self._client_ip,
+            )
+            self.send_response(200)
+            self.send_header("Content-Type", "text/csv; charset=utf-8")
+            self.send_header(
+                "Content-Disposition",
+                'attachment; filename="intercompany-export.csv"',
+            )
+            self.send_header("Content-Length", str(len(content)))
+            self.send_header("Cache-Control", "no-store")
+            self.end_headers()
+            self.wfile.write(content)
+        finally:
+            connection.close()
+
     def _handle_company_intercompany_balances(self, query: dict[str, list[str]]) -> None:
         connection = connect(DB_PATH)
         try:

src/bank_importer/company_transfers.py

@@ -1,22 +1,32 @@
-"""Company-portal intercompany transfer summary (HEL-175 / HEL-169).
+"""Company-portal intercompany transfer summary / detail / export (HEL-175/176).
 
 Confirmed totals reuse the authoritative ``eligible_intercompany_events``
 view (intercompany + paired or locked). Pending counts/amounts are listed
 separately and never enter outflow, inflow or net. All money math uses
 ``Decimal`` on stored TEXT amounts — never float or SQLite SUM.
+
+Detail listing (HEL-176) applies counterparty / date / direction / state
+filters inside SQL before LIMIT, and uses keyset pagination on
+(effective_at, event_id) descending. Export only ships confirmed rows.
 """
 
 from __future__ import annotations
 
+import base64
+import csv
+import io
 from datetime import datetime, timedelta, timezone
 from decimal import Decimal, InvalidOperation
 import re
 import sqlite3
 
-from . import settings
+from . import matching, settings
 
 _DATE_RE = re.compile(r"^\d{4}-\d{2}-\d{2}$")
 _ZERO = Decimal("0.00")
+_DEFAULT_PAGE = 50
+_MAX_PAGE = 200
+_MAX_EXPORT_ROWS = 20000
 
 
 class TransferSummaryInputError(ValueError):
@@ -296,3 +306,435 @@ def company_intercompany_summary(
         },
         "counterparties": counterparties,
     }
+
+
+# ---------------------------------------------------------------------------
+# Detail list + CSV export (HEL-176)
+# ---------------------------------------------------------------------------
+
+
+def encode_cursor(effective_at: str, event_id: int) -> str:
+    raw = f"{effective_at}|{event_id}"
+    return base64.urlsafe_b64encode(raw.encode("utf-8")).decode("ascii")
+
+
+def decode_cursor(cursor: str | None) -> tuple[str, int] | None:
+    if not cursor:
+        return None
+    try:
+        raw = base64.urlsafe_b64decode(cursor.encode("ascii")).decode("utf-8")
+        effective_at, event_id_text = raw.split("|", 1)
+        return effective_at, int(event_id_text)
+    except Exception as exc:
+        raise TransferSummaryInputError("分页游标无效。") from exc
+
+
+def _parse_limit(raw: object | None, default: int = _DEFAULT_PAGE) -> int:
+    if raw is None or str(raw).strip() == "":
+        return default
+    try:
+        value = int(str(raw).strip())
+    except (TypeError, ValueError) as exc:
+        raise TransferSummaryInputError("limit 必须是正整数。") from exc
+    if value < 1:
+        raise TransferSummaryInputError("limit 必须是正整数。")
+    return min(value, _MAX_PAGE)
+
+
+def _parse_optional_date(raw: object | None, label: str) -> str | None:
+    if raw is None or str(raw).strip() == "":
+        return None
+    return _validate_date(raw, label)
+
+
+def _parse_direction(raw: object | None) -> str | None:
+    if raw is None or str(raw).strip() == "":
+        return None
+    value = str(raw).strip().lower()
+    if value not in ("out", "in"):
+        raise TransferSummaryInputError("direction 只能是 out 或 in。")
+    return value
+
+
+def _parse_state(raw: object | None) -> str | None:
+    if raw is None or str(raw).strip() == "":
+        return None
+    value = str(raw).strip().lower()
+    if value not in ("confirmed", "pending"):
+        raise TransferSummaryInputError("state 只能是 confirmed 或 pending。")
+    return value
+
+
+def _parse_counterparty_id(raw: object | None) -> int | None:
+    if raw is None or str(raw).strip() == "":
+        return None
+    try:
+        value = int(str(raw).strip())
+    except (TypeError, ValueError) as exc:
+        raise TransferSummaryInputError("counterparty_id 参数无效。") from exc
+    if value < 1:
+        raise TransferSummaryInputError("counterparty_id 参数无效。")
+    return value
+
+
+def _event_window(
+    connection: sqlite3.Connection,
+    *,
+    from_: str | None,
+    to: str | None,
+) -> tuple[str, str]:
+    end = _parse_optional_date(to, "to") or today_shanghai()
+    start_default = settings.get_settings(connection).get("start_date") or "2026-01-01"
+    start = _parse_optional_date(from_, "from") or _validate_date(
+        start_default, "start_date"
+    )
+    if start > end:
+        raise TransferSummaryInputError("from 不能晚于 to。")
+    return start, end
+
+
+# Confirmed = eligible_intercompany_events. Pending matches summary tip set.
+_CONFIRMED_PREDICATE = """
+    d.classification = 'intercompany'
+    AND (d.pairing = 'paired' OR d.locked = 1)
+"""
+
+_PENDING_PREDICATE = """
+    (
+        d.classification IN ('unresolved', 'needs_review', 'internal_single')
+     OR (
+            d.classification = 'intercompany'
+        AND d.pairing != 'paired'
+        AND d.locked = 0
+     )
+    )
+"""
+
+_BOTH_PREDICATE = f"""
+    (
+        ({_CONFIRMED_PREDICATE})
+     OR ({_PENDING_PREDICATE})
+    )
+"""
+
+
+def _state_predicate(state: str | None) -> str:
+    if state == "confirmed":
+        return f"({_CONFIRMED_PREDICATE})"
+    if state == "pending":
+        return f"({_PENDING_PREDICATE})"
+    return _BOTH_PREDICATE
+
+
+def _list_select_sql() -> str:
+    return """
+        SELECT c.event_id, d.id AS decision_id, d.revision, d.classification,
+               d.pairing, d.amount, d.currency, d.effective_at, d.mode,
+               d.locked, d.rule_version, d.created_at, d.reason,
+               payer.company_id AS payer_company_id,
+               payee.company_id AS payee_company_id,
+               payer.bank_account_id AS payer_account_id,
+               payee.bank_account_id AS payee_account_id,
+               cpayer.name AS payer_company_name,
+               cpayee.name AS payee_company_name,
+               (SELECT COUNT(*) FROM transfer_decision_observations o
+                WHERE o.decision_id = d.id) AS evidence_count,
+               (SELECT r.summary
+                FROM transfer_decision_observations o
+                JOIN source_rows r ON r.id = o.source_row_id
+                JOIN sheet_batches s ON s.id = r.sheet_batch_id
+                JOIN import_batches b ON b.id = s.import_batch_id
+                WHERE o.decision_id = d.id AND b.company_id = ?
+                ORDER BY o.id
+                LIMIT 1) AS summary
+        FROM current_transfer_decisions c
+        JOIN transfer_match_decisions d ON d.id = c.decision_id
+        JOIN canonical_transfer_events e ON e.id = c.event_id
+        LEFT JOIN transfer_decision_participants payer
+             ON payer.decision_id = d.id AND payer.role = 'payer'
+        LEFT JOIN transfer_decision_participants payee
+             ON payee.decision_id = d.id AND payee.role = 'payee'
+        LEFT JOIN companies cpayer ON cpayer.id = payer.company_id
+        LEFT JOIN companies cpayee ON cpayee.id = payee.company_id
+    """
+
+
+def _build_event_filters(
+    *,
+    company_id: int,
+    start: str,
+    end: str,
+    counterparty_id: int | None,
+    direction: str | None,
+    state: str | None,
+    cursor: tuple[str, int] | None,
+) -> tuple[str, list[object]]:
+    conditions = [
+        "e.lifecycle = 'active'",
+        "(payer.company_id = ? OR payee.company_id = ?)",
+        "d.effective_at >= ?",
+        "d.effective_at <= ?",
+        _state_predicate(state),
+    ]
+    params: list[object] = [
+        company_id,
+        company_id,
+        start,
+        end + "T23:59:59",
+    ]
+
+    if counterparty_id is not None:
+        # Counterparty is the other participant; own company stays forced above.
+        conditions.append(
+            """
+            (
+                (payer.company_id = ? AND payee.company_id = ?)
+             OR (payee.company_id = ? AND payer.company_id = ?)
+            )
+            """
+        )
+        params.extend([company_id, counterparty_id, company_id, counterparty_id])
+
+    if direction == "out":
+        conditions.append("payer.company_id = ?")
+        params.append(company_id)
+    elif direction == "in":
+        conditions.append("payee.company_id = ?")
+        params.append(company_id)
+
+    if cursor is not None:
+        cursor_at, cursor_id = cursor
+        conditions.append(
+            """
+            (
+                d.effective_at < ?
+             OR (d.effective_at = ? AND c.event_id < ?)
+            )
+            """
+        )
+        params.extend([cursor_at, cursor_at, cursor_id])
+
+    where = " WHERE " + " AND ".join(conditions)
+    return where, params
+
+
+def _row_state(row: sqlite3.Row) -> str:
+    classification = row["classification"]
+    pairing = row["pairing"]
+    locked = bool(row["locked"])
+    if classification == "intercompany" and (pairing == "paired" or locked):
+        return "confirmed"
+    return "pending"
+
+
+def _row_direction(row: sqlite3.Row, company_id: int) -> str | None:
+    if row["payer_company_id"] is not None and int(row["payer_company_id"]) == int(
+        company_id
+    ):
+        return "out"
+    if row["payee_company_id"] is not None and int(row["payee_company_id"]) == int(
+        company_id
+    ):
+        return "in"
+    return None
+
+
+def _event_list_item(row: sqlite3.Row, company_id: int) -> dict[str, object]:
+    direction = _row_direction(row, company_id)
+    state = _row_state(row)
+    if direction == "out":
+        counterparty_company_id = row["payee_company_id"]
+        counterparty_company_name = row["payee_company_name"]
+    else:
+        counterparty_company_id = row["payer_company_id"]
+        counterparty_company_name = row["payer_company_name"]
+    summary = row["summary"] or row["reason"] or ""
+    return {
+        "event_id": int(row["event_id"]),
+        "decision_id": int(row["decision_id"]),
+        "revision": row["revision"],
+        "classification": row["classification"],
+        "pairing": row["pairing"],
+        "status": matching.exposed_status(row),
+        "state": state,
+        "direction": direction,
+        "amount": row["amount"],
+        "currency": row["currency"],
+        "effective_at": row["effective_at"],
+        "mode": row["mode"],
+        "locked": bool(row["locked"]),
+        "rule_version": row["rule_version"],
+        "summary": summary,
+        "own_company_id": company_id,
+        "counterparty_company_id": (
+            int(counterparty_company_id) if counterparty_company_id is not None else None
+        ),
+        "counterparty_company_name": counterparty_company_name,
+        "evidence_count": row["evidence_count"],
+    }
+
+
+def company_intercompany_events(
+    connection: sqlite3.Connection,
+    *,
+    company_id: int,
+    from_: str | None = None,
+    to: str | None = None,
+    counterparty_id: int | None | object = None,
+    direction: str | None | object = None,
+    state: str | None | object = None,
+    limit: object | None = None,
+    cursor: str | None = None,
+) -> dict[str, object]:
+    """Filtered keyset page of company-visible transfer events (HEL-176)."""
+    start, end = _event_window(connection, from_=from_, to=to)
+    cp_id = _parse_counterparty_id(counterparty_id)
+    direction_value = _parse_direction(direction)
+    state_value = _parse_state(state)
+    page_size = _parse_limit(limit)
+    cursor_tuple = decode_cursor(cursor)
+
+    where, params = _build_event_filters(
+        company_id=company_id,
+        start=start,
+        end=end,
+        counterparty_id=cp_id,
+        direction=direction_value,
+        state=state_value,
+        cursor=cursor_tuple,
+    )
+    # summary subquery binds own company_id first.
+    sql = (
+        _list_select_sql()
+        + where
+        + " ORDER BY d.effective_at DESC, c.event_id DESC LIMIT ?"
+    )
+    rows = connection.execute(
+        sql, (company_id, *params, page_size + 1)
+    ).fetchall()
+
+    has_more = len(rows) > page_size
+    page = rows[:page_size]
+    items = [_event_list_item(row, company_id) for row in page]
+    next_cursor = None
+    if has_more and page:
+        last = page[-1]
+        next_cursor = encode_cursor(str(last["effective_at"]), int(last["event_id"]))
+
+    return {
+        "window": {"start": start, "end": end},
+        "events": items,
+        "next_cursor": next_cursor,
+        "has_more": has_more,
+    }
+
+
+def company_intercompany_export_rows(
+    connection: sqlite3.Connection,
+    *,
+    company_id: int,
+    from_: str | None = None,
+    to: str | None = None,
+    counterparty_id: int | None | object = None,
+    direction: str | None | object = None,
+) -> tuple[list[dict[str, object]], dict[str, object]]:
+    """Confirmed-only rows for CSV export; pending never included."""
+    start, end = _event_window(connection, from_=from_, to=to)
+    cp_id = _parse_counterparty_id(counterparty_id)
+    direction_value = _parse_direction(direction)
+
+    where, params = _build_event_filters(
+        company_id=company_id,
+        start=start,
+        end=end,
+        counterparty_id=cp_id,
+        direction=direction_value,
+        state="confirmed",
+        cursor=None,
+    )
+    sql = (
+        _list_select_sql()
+        + where
+        + " ORDER BY d.effective_at DESC, c.event_id DESC LIMIT ?"
+    )
+    rows = connection.execute(
+        sql, (company_id, *params, _MAX_EXPORT_ROWS + 1)
+    ).fetchall()
+    if len(rows) > _MAX_EXPORT_ROWS:
+        raise TransferSummaryInputError(
+            f"导出行数超过上限 {_MAX_EXPORT_ROWS}，请缩小筛选范围。"
+        )
+    items = [_event_list_item(row, company_id) for row in rows]
+    meta = {
+        "start": start,
+        "end": end,
+        "counterparty_id": cp_id,
+        "direction": direction_value,
+        "state": "confirmed",
+        "row_count": len(items),
+    }
+    return items, meta
+
+
+def render_intercompany_export_csv(items: list[dict[str, object]]) -> bytes:
+    buffer = io.StringIO()
+    writer = csv.writer(buffer)
+    writer.writerow(
+        [
+            "日期",
+            "方向",
+            "对方公司",
+            "金额",
+            "币种",
+            "摘要",
+            "状态",
+            "配对",
+            "事件ID",
+            "决策ID",
+        ]
+    )
+    direction_label = {"out": "转出", "in": "转入"}
+    for item in items:
+        writer.writerow(
+            [
+                item.get("effective_at") or "",
+                direction_label.get(str(item.get("direction") or ""), ""),
+                item.get("counterparty_company_name") or "",
+                item.get("amount") or "",
+                item.get("currency") or "",
+                item.get("summary") or "",
+                "已确认",
+                item.get("pairing") or "",
+                item.get("event_id") or "",
+                item.get("decision_id") or "",
+            ]
+        )
+    # UTF-8 BOM so Excel opens the CSV with the right encoding.
+    return (chr(0xFEFF) + buffer.getvalue()).encode("utf-8")
+
+
+def is_transfer_summary_events_query(query: dict[str, list[str]]) -> bool:
+    """Discriminate HEL-176 transfer list from B-44 ledger ``/events``.
+
+    B-44 uses ``cutoff`` / subject / posting_kind / source_kind / pending_subject.
+    HEL-176 uses ``to`` / direction / counterparty_id / state=pending|confirmed
+    (without ledger-only knobs).
+    """
+    if (query.get("direction") or [None])[0] is not None:
+        return True
+    if (query.get("counterparty_id") or [None])[0] is not None:
+        return True
+    if (query.get("to") or [None])[0] is not None:
+        return True
+    state = (query.get("state") or [None])[0]
+    if state in ("pending", "confirmed") and (query.get("cutoff") or [None])[0] is None:
+        # Bare state=confirmed without cutoff is the transfer-summary list;
+        # B-44 confirmed always pairs with cutoff in existing callers/tests.
+        if (query.get("subject") or [None])[0] is not None:
+            return False
+        if (query.get("posting_kind") or [None])[0] is not None:
+            return False
+        if (query.get("source_kind") or [None])[0] is not None:
+            return False
+        return True
+    return False

tests/test_company_transfer_events.py

@@ -0,0 +1,500 @@
+"""HTTP tests for company intercompany events list + CSV export (HEL-176).
+
+Covers combined filters, keyset pagination, empty state, lateral access,
+forged company_id, ID guessing, export isolation and audit logging.
+"""
+
+from __future__ import annotations
+
+import io
+import json
+import os
+from pathlib import Path
+import tempfile
+import threading
+import unittest
+
+from openpyxl import Workbook
+
+from bank_importer.db import connect, migrate
+
+import server
+from test_server_auth import Client, as_json
+
+BOOTSTRAP_PASSWORD = "BootAdmin123"
+ADMIN_PASSWORD = "AdminPass123"
+CASHIER_PASSWORD = "Cashier123"
+
+CCB_HEADER = [
+    "客户账号", "账户名称", "交易时间", "借方发生额（支取）", "贷方发生额（收入）",
+    "余额", "币种", "对方户名", "对方账号", "对方开户机构", "摘要", "备注",
+]
+
+ACCOUNT_A = "6222000000000001"
+ACCOUNT_B = "6222000000000002"
+ACCOUNT_C = "6222000000000003"
+
+
+def workbook_bytes(rows) -> bytes:
+    workbook = Workbook()
+    sheet = workbook.active
+    sheet.title = "正常流水"
+    sheet.append(CCB_HEADER)
+    for row in rows:
+        sheet.append(row)
+    buffer = io.BytesIO()
+    workbook.save(buffer)
+    return buffer.getvalue()
+
+
+def outgoing(own: str, cp: str, amount: str, at: str = "2026-01-05 10:00:00"):
+    return [own, "测试公司", at, amount, "", "50000.00", "RMB", "对方", cp, "某银行", "货款", ""]
+
+
+def incoming(own: str, cp: str, amount: str, at: str = "2026-01-05 11:00:00"):
+    return [own, "测试公司", at, "", amount, "50000.00", "RMB", "对方", cp, "某银行", "收款", ""]
+
+
+class CompanyIntercompanyEventsTests(unittest.TestCase):
+    def setUp(self) -> None:
+        self.temp_dir = tempfile.TemporaryDirectory()
+        self.addCleanup(self.temp_dir.cleanup)
+        root = Path(self.temp_dir.name)
+        self.db_path = root / "app.db"
+        self.storage = root / "files"
+
+        self._old_db_path = server.DB_PATH
+        self._old_storage = server.STORAGE_DIR
+        server.DB_PATH = self.db_path
+        server.STORAGE_DIR = self.storage
+
+        os.environ["APP_BOOTSTRAP_ADMIN_PASSWORD"] = BOOTSTRAP_PASSWORD
+        connection = connect(self.db_path)
+        migrate(connection)
+        assert server.ensure_bootstrap_admin(connection) is None
+        connection.close()
+
+        class QuietHandler(server.AppHandler):
+            def log_message(self, *args) -> None:
+                pass
+
+        self.httpd = server.ThreadingHTTPServer(("127.0.0.1", 0), QuietHandler)
+        self.port = self.httpd.server_address[1]
+        self.thread = threading.Thread(target=self.httpd.serve_forever, daemon=True)
+        self.thread.start()
+
+        self.admin = Client("127.0.0.1", self.port)
+        status, _, data = self.admin.post_json(
+            "/api/login",
+            {"username": "group-admin", "password": BOOTSTRAP_PASSWORD, "portal": "admin"},
+        )
+        assert status == 200, data
+        status, _, data = self.admin.post_json(
+            "/api/password/change",
+            {"old_password": BOOTSTRAP_PASSWORD, "new_password": ADMIN_PASSWORD},
+        )
+        assert status == 200, data
+
+        self.initial_passwords: dict[str, str] = {}
+        self.company_a = self._create_company("甲公司", "cashier-a")
+        self.company_b = self._create_company("乙公司", "cashier-b")
+        self.company_c = self._create_company("丙公司", "cashier-c")
+        self.cashier_a = self._login_company("cashier-a")
+        self.cashier_b = self._login_company("cashier-b")
+        self.cashier_c = self._login_company("cashier-c")
+
+        self._approve_account(self.company_a, ACCOUNT_A, self.cashier_a)
+        self._approve_account(self.company_b, ACCOUNT_B, self.cashier_b)
+        self._approve_account(self.company_c, ACCOUNT_C, self.cashier_c)
+
+    def tearDown(self) -> None:
+        self.httpd.shutdown()
+        self.httpd.server_close()
+        server.DB_PATH = self._old_db_path
+        server.STORAGE_DIR = self._old_storage
+        os.environ.pop("APP_BOOTSTRAP_ADMIN_PASSWORD", None)
+
+    def _create_company(self, name: str, username: str) -> int:
+        status, _, data = self.admin.post_json(
+            "/api/admin/companies", {"name": name, "username": username}
+        )
+        assert status == 200, data
+        self.initial_passwords[username] = as_json(data)["initial_password"]
+        return as_json(data)["company_id"]
+
+    def _login_company(self, username: str) -> Client:
+        client = Client("127.0.0.1", self.port)
+        initial = self.initial_passwords[username]
+        status, _, data = client.post_json(
+            "/api/login", {"username": username, "password": initial, "portal": "company"}
+        )
+        assert status == 200, data
+        status, _, data = client.post_json(
+            "/api/password/change",
+            {"old_password": initial, "new_password": CASHIER_PASSWORD},
+        )
+        assert status == 200, data
+        return client
+
+    def _approve_account(self, company_id: int, number: str, client: Client) -> int:
+        status, _, data = client.post_json(
+            "/api/company/accounts",
+            {
+                "bank_name": "中信银行",
+                "account_type": "基本户",
+                "account_number": number,
+                "start_date": "2026-01-01",
+            },
+        )
+        assert status == 200, data
+        account_id = as_json(data)["account"]["id"]
+        status, _, data = self.admin.post_json(
+            f"/api/admin/accounts/{account_id}/review",
+            {
+                "decision": "approve",
+                "reason": "测试启用",
+                "effective_from": "2026-01-01",
+            },
+        )
+        assert status == 200, data
+        return account_id
+
+    def _upload_and_confirm(self, client: Client, company_id: int, rows) -> int:
+        content = workbook_bytes(rows)
+        status, _, data = self.admin.post_multipart(
+            "/api/parse", {"company_id": str(company_id)}, "账单.xlsx", content
+        )
+        assert status == 200, data
+        batch_id = as_json(data)["batch_id"]
+        status, _, data = client.get(f"/api/batches/{batch_id}/sheets")
+        names = [s["sheet_name"] for s in as_json(data)["sheets"] if s["outcome"] == "parsed"]
+        status, _, data = client.post_json(
+            f"/api/batches/{batch_id}/confirm", {"sheets": names}
+        )
+        assert status == 200, data
+        return batch_id
+
+    def _lock_single(self, amount: str, at: str = "2026-03-01 10:00:00") -> dict:
+        self._upload_and_confirm(
+            self.cashier_a,
+            self.company_a,
+            [outgoing(ACCOUNT_A, ACCOUNT_B, amount, at)],
+        )
+        status, _, data = self.admin.get("/api/admin/transfer-events")
+        self.assertEqual(200, status, data)
+        single = next(
+            e
+            for e in as_json(data)["events"]
+            if e["status"] == "internal_single" and e["amount"] == amount
+        )
+        status, _, data = self.admin.get(f"/api/admin/transfer-events/{single['event_id']}")
+        self.assertEqual(200, status, data)
+        revision = as_json(data)["event"]["revision"]
+        status, _, data = self.admin.post_json(
+            f"/api/admin/transfer-events/{single['event_id']}/decisions",
+            {
+                "action": "assign_participant",
+                "reason": "函证确认",
+                "expected_revision": revision,
+                "request_key": f"lock-{amount}-{at}",
+                "participant": {"role": "payee", "company_id": self.company_b},
+            },
+        )
+        self.assertEqual(200, status, data)
+        return as_json(data)["decision"]
+
+    def _seed_mixed(self) -> None:
+        """Paired A→B 100, B→A 40, locked A→B 25, pending A→B 7, B→C 200."""
+        self._upload_and_confirm(
+            self.cashier_a, self.company_a,
+            [outgoing(ACCOUNT_A, ACCOUNT_B, "100.00", "2026-01-05 10:00:00")],
+        )
+        self._upload_and_confirm(
+            self.cashier_b, self.company_b,
+            [incoming(ACCOUNT_B, ACCOUNT_A, "100.00", "2026-01-05 11:00:00")],
+        )
+        self._upload_and_confirm(
+            self.cashier_b, self.company_b,
+            [outgoing(ACCOUNT_B, ACCOUNT_A, "40.00", "2026-01-10 10:00:00")],
+        )
+        self._upload_and_confirm(
+            self.cashier_a, self.company_a,
+            [incoming(ACCOUNT_A, ACCOUNT_B, "40.00", "2026-01-10 11:00:00")],
+        )
+        self._lock_single("25.00", "2026-02-01 10:00:00")
+        self._upload_and_confirm(
+            self.cashier_a, self.company_a,
+            [outgoing(ACCOUNT_A, ACCOUNT_B, "7.00", "2026-02-15 10:00:00")],
+        )
+        self._upload_and_confirm(
+            self.cashier_b, self.company_b,
+            [outgoing(ACCOUNT_B, ACCOUNT_C, "200.00", "2026-01-20 10:00:00")],
+        )
+        self._upload_and_confirm(
+            self.cashier_c, self.company_c,
+            [incoming(ACCOUNT_C, ACCOUNT_B, "200.00", "2026-01-20 11:00:00")],
+        )
+
+    def _events(self, client: Client, query: str = "from=2026-01-01&to=2026-12-31"):
+        status, _, data = client.get(f"/api/company/intercompany/events?{query}")
+        return status, as_json(data) if data else {}
+
+    def _export(self, client: Client, query: str = "from=2026-01-01&to=2026-12-31"):
+        return client.get(f"/api/company/intercompany/export.csv?{query}")
+
+    # ------------------------------------------------------------------
+    # Auth / parameter guards
+    # ------------------------------------------------------------------
+
+    def test_requires_company_role(self) -> None:
+        status, payload = self._events(self.admin)
+        self.assertEqual(403, status, payload)
+
+    def test_rejects_forged_company_id_on_events_and_export(self) -> None:
+        status, payload = self._events(
+            self.cashier_a,
+            f"from=2026-01-01&to=2026-12-31&company_id={self.company_b}",
+        )
+        self.assertEqual(400, status, payload)
+
+        status, _, data = self._export(
+            self.cashier_a,
+            f"from=2026-01-01&to=2026-12-31&company_id={self.company_a}",
+        )
+        self.assertEqual(400, status, data)
+
+    def test_rejects_bad_filters(self) -> None:
+        status, payload = self._events(
+            self.cashier_a, "from=2026-01-01&to=2026-12-31&direction=sideways"
+        )
+        self.assertEqual(400, status, payload)
+        status, payload = self._events(
+            self.cashier_a, "from=2026-01-01&to=2026-12-31&state=maybe"
+        )
+        self.assertEqual(400, status, payload)
+        status, payload = self._events(
+            self.cashier_a, "from=2026-13-40&to=2026-12-31"
+        )
+        self.assertEqual(400, status, payload)
+
+    def test_empty_window(self) -> None:
+        status, payload = self._events(self.cashier_a)
+        self.assertEqual(200, status, payload)
+        self.assertEqual([], payload["events"])
+        self.assertFalse(payload["has_more"])
+        self.assertIsNone(payload["next_cursor"])
+
+    # ------------------------------------------------------------------
+    # Combined filters + confirmed/pending separation
+    # ------------------------------------------------------------------
+
+    def test_combined_filters_and_state_split(self) -> None:
+        self._seed_mixed()
+
+        status, payload = self._events(self.cashier_a)
+        self.assertEqual(200, status, payload)
+        events = payload["events"]
+        # A sees: out 100, in 40, locked out 25, pending out 7 — not B↔C 200
+        self.assertEqual(4, len(events))
+        amounts = {e["amount"] for e in events}
+        self.assertEqual({"100.00", "40.00", "25.00", "7.00"}, amounts)
+        for event in events:
+            self.assertNotEqual(self.company_c, event["counterparty_company_id"])
+            self.assertIn(event["state"], ("confirmed", "pending"))
+            self.assertIn(event["direction"], ("out", "in"))
+
+        status, confirmed = self._events(
+            self.cashier_a, "from=2026-01-01&to=2026-12-31&state=confirmed"
+        )
+        self.assertEqual(200, status, confirmed)
+        self.assertEqual(3, len(confirmed["events"]))
+        self.assertTrue(all(e["state"] == "confirmed" for e in confirmed["events"]))
+        self.assertNotIn("7.00", {e["amount"] for e in confirmed["events"]})
+
+        status, pending = self._events(
+            self.cashier_a, "from=2026-01-01&to=2026-12-31&state=pending"
+        )
+        self.assertEqual(200, status, pending)
+        self.assertEqual(1, len(pending["events"]))
+        self.assertEqual("7.00", pending["events"][0]["amount"])
+        self.assertEqual("pending", pending["events"][0]["state"])
+
+        status, outs = self._events(
+            self.cashier_a, "from=2026-01-01&to=2026-12-31&direction=out&state=confirmed"
+        )
+        self.assertEqual(200, status, outs)
+        self.assertEqual({"100.00", "25.00"}, {e["amount"] for e in outs["events"]})
+        self.assertTrue(all(e["direction"] == "out" for e in outs["events"]))
+
+        status, by_cp = self._events(
+            self.cashier_a,
+            f"from=2026-01-01&to=2026-12-31&counterparty_id={self.company_b}&state=confirmed",
+        )
+        self.assertEqual(200, status, by_cp)
+        self.assertEqual(3, len(by_cp["events"]))
+
+        # Date window excludes Feb locked/pending
+        status, jan = self._events(
+            self.cashier_a, "from=2026-01-01&to=2026-01-31&state=confirmed"
+        )
+        self.assertEqual(200, status, jan)
+        self.assertEqual({"100.00", "40.00"}, {e["amount"] for e in jan["events"]})
+
+    def test_keyset_pagination_no_dup_no_gap(self) -> None:
+        # Three confirmed A→B outs on distinct days
+        for i, amount in enumerate(("11.00", "12.00", "13.00", "14.00", "15.00")):
+            day = 5 + i
+            self._upload_and_confirm(
+                self.cashier_a, self.company_a,
+                [outgoing(ACCOUNT_A, ACCOUNT_B, amount, f"2026-01-{day:02d} 10:00:00")],
+            )
+            self._upload_and_confirm(
+                self.cashier_b, self.company_b,
+                [incoming(ACCOUNT_B, ACCOUNT_A, amount, f"2026-01-{day:02d} 11:00:00")],
+            )
+
+        status, page1 = self._events(
+            self.cashier_a,
+            "from=2026-01-01&to=2026-12-31&state=confirmed&direction=out&limit=2",
+        )
+        self.assertEqual(200, status, page1)
+        self.assertEqual(2, len(page1["events"]))
+        self.assertTrue(page1["has_more"])
+        self.assertIsNotNone(page1["next_cursor"])
+
+        status, page2 = self._events(
+            self.cashier_a,
+            "from=2026-01-01&to=2026-12-31&state=confirmed&direction=out"
+            f"&limit=2&cursor={page1['next_cursor']}",
+        )
+        self.assertEqual(200, status, page2)
+        self.assertEqual(2, len(page2["events"]))
+        self.assertTrue(page2["has_more"])
+
+        status, page3 = self._events(
+            self.cashier_a,
+            "from=2026-01-01&to=2026-12-31&state=confirmed&direction=out"
+            f"&limit=2&cursor={page2['next_cursor']}",
+        )
+        self.assertEqual(200, status, page3)
+        self.assertEqual(1, len(page3["events"]))
+        self.assertFalse(page3["has_more"])
+        self.assertIsNone(page3["next_cursor"])
+
+        ids = [e["event_id"] for e in page1["events"] + page2["events"] + page3["events"]]
+        self.assertEqual(5, len(ids))
+        self.assertEqual(len(ids), len(set(ids)))
+        # Descending by effective_at then event_id
+        amounts = [e["amount"] for e in page1["events"] + page2["events"] + page3["events"]]
+        self.assertEqual(["15.00", "14.00", "13.00", "12.00", "11.00"], amounts)
+
+    # ------------------------------------------------------------------
+    # Isolation / ID guess / detail reuse
+    # ------------------------------------------------------------------
+
+    def test_lateral_isolation_and_id_guess_404(self) -> None:
+        self._seed_mixed()
+
+        status, payload_a = self._events(self.cashier_a)
+        self.assertEqual(200, status, payload_a)
+        a_ids = {e["event_id"] for e in payload_a["events"]}
+
+        status, payload_c = self._events(self.cashier_c)
+        self.assertEqual(200, status, payload_c)
+        # C only participates in B↔C 200
+        self.assertTrue(payload_c["events"])
+        for event in payload_c["events"]:
+            self.assertEqual("200.00", event["amount"])
+            self.assertNotIn(event["event_id"], a_ids)
+
+        # C guessing A's event id via transfer-events detail → 404
+        a_event_id = next(iter(a_ids))
+        status, _, data = self.cashier_c.get(
+            f"/api/company/transfer-events/{a_event_id}"
+        )
+        self.assertEqual(404, status, data)
+
+        # A can open own event; counterparty account masked; only own observations
+        status, _, data = self.cashier_a.get(
+            f"/api/company/transfer-events/{a_event_id}"
+        )
+        self.assertEqual(200, status, data)
+        detail = as_json(data)["event"]
+        if detail.get("counterparty") and "account_number_masked" in detail["counterparty"]:
+            masked = detail["counterparty"]["account_number_masked"]
+            self.assertTrue(str(masked).startswith("****"))
+            self.assertNotIn(ACCOUNT_B, masked)
+        for obs in detail["observations"]:
+            self.assertEqual(self.company_a, obs["batch_company_id"])
+            self.assertNotIn(ACCOUNT_B, json.dumps(obs, ensure_ascii=False))
+
+        # Filtering by counterparty C still cannot leak B↔C into A's list
+        status, filtered = self._events(
+            self.cashier_a,
+            f"from=2026-01-01&to=2026-12-31&counterparty_id={self.company_c}",
+        )
+        self.assertEqual(200, status, filtered)
+        self.assertEqual([], filtered["events"])
+
+    def test_b44_events_path_still_works_with_cutoff(self) -> None:
+        # Without HEL-176 discriminators, /events stays on B-44 ledger list.
+        status, _, data = self.cashier_a.get(
+            "/api/company/intercompany/events?from=2026-01-01&cutoff=2026-12-31"
+        )
+        self.assertEqual(200, status, data)
+        payload = as_json(data)
+        self.assertIn("items", payload)
+        self.assertNotIn("events", payload)
+
+    # ------------------------------------------------------------------
+    # Export: confirmed only + audit + isolation
+    # ------------------------------------------------------------------
+
+    def test_export_confirmed_only_isolated_and_audited(self) -> None:
+        self._seed_mixed()
+
+        status, headers, data = self._export(self.cashier_a)
+        self.assertEqual(200, status, data)
+        self.assertEqual("text/csv; charset=utf-8", headers.get("content-type"))
+        text = data.decode("utf-8-sig")
+        lines = [line for line in text.splitlines() if line]
+        self.assertGreaterEqual(len(lines), 2)
+        body = "\n".join(lines[1:])
+        self.assertIn("100.00", body)
+        self.assertIn("40.00", body)
+        self.assertIn("25.00", body)
+        self.assertNotIn("7.00", body)  # pending excluded
+        self.assertNotIn("200.00", body)  # B↔C excluded
+
+        # Explicit pending state rejected
+        status, _, data = self._export(
+            self.cashier_a, "from=2026-01-01&to=2026-12-31&state=pending"
+        )
+        self.assertEqual(400, status, data)
+
+        # C export must not contain A's amounts
+        status, _, data = self._export(self.cashier_c)
+        self.assertEqual(200, status, data)
+        text_c = data.decode("utf-8-sig")
+        self.assertNotIn("100.00", text_c)
+        self.assertNotIn("25.00", text_c)
+        self.assertIn("200.00", text_c)
+
+        status, _, data = self.admin.get("/api/admin/audit-log?limit=50")
+        self.assertEqual(200, status, data)
+        actions = [row["action"] for row in as_json(data)["entries"]]
+        self.assertIn("export_intercompany_csv", actions)
+        export_rows = [
+            row
+            for row in as_json(data)["entries"]
+            if row["action"] == "export_intercompany_csv"
+        ]
+        self.assertTrue(export_rows)
+        self.assertTrue(
+            any(f"company:{self.company_a}" == row.get("target") for row in export_rows)
+        )
+        self.assertTrue(any("state:confirmed" in (row.get("detail") or "") for row in export_rows))
+
+
+if __name__ == "__main__":
+    unittest.main()