from flask import Blueprint, jsonify, request  # .material -> .base refactor checked
from flask_jwt_extended import jwt_required, get_jwt_identity, get_jwt
from app.utils.decorators import permission_required, prevent_double_submit, is_privileged_viewer
from app.services.auth_service import AuthService
from app.services.trans_service import TransService
from app.services.borrow_service import BorrowApprovalService
import traceback

trans_bp = Blueprint('transactions', __name__, url_prefix='/transactions')


# ==============================================================================
# 辅助函数：获取当前用户的完整权限列表（基于角色查询）
# ==============================================================================
def get_current_user_permissions():
    """
    返回当前用户拥有的所有权限码列表（包括菜单和元素）
    此函数根据角色查询数据库得到权限。
    """
    claims = get_jwt()
    user_role = claims.get('role')
    user_company = claims.get('company_name', '')
    if not user_role:
        return []
    # 超级管理员返回所有字段权限 (忽略大小写)
    if user_role.upper() == 'SUPER_ADMIN':
        return ['*']
    perm_dict = AuthService.get_user_permissions(user_role, company_name=user_company)
    # 合并菜单和元素权限
    perms = perm_dict.get('menus', []) + perm_dict.get('elements', [])
    return perms


def get_current_user_info():
    """获取当前用户信息和角色"""
    from app.models.system import SysUser
    identity = get_jwt_identity()
    if not identity:
        return None, None
    user = SysUser.query.get(identity)
    return user.id if user else None, user.role if user else None


def _current_username():
    """获取当前登录用户的用户名（姓名/账号），用于操作人展示；避免把 JWT 数字 ID 存进记录"""
    identity = get_jwt_identity()
    if not identity:
        return 'System'
    from app.models.system import SysUser
    user = SysUser.query.get(identity)
    return user.username if user else str(identity)


def filter_item_by_permissions(item_dict, user_permissions, prefix='op_records'):
    """
    根据用户权限过滤 item 字典，无权限的字段值置为 None

    ★ Fail-Closed: 字段映射默认为完整列表，不再为空字典。
    """
    # sys_element 补齐前不做字段级过滤
    field_to_perm = {}
    if '*' in user_permissions or f'{prefix}:*' in user_permissions:
        return item_dict
    for field, perm_code in field_to_perm.items():
        if field in item_dict and perm_code not in user_permissions:
            item_dict[field] = None
    return item_dict


# --- 借库接口 ---
@trans_bp.route('/borrow', methods=['POST'])
@jwt_required()
@permission_required('op_borrow:operation')
def create_borrow():
    data = request.get_json()
    try:
        no = TransService.create_borrow(data)
        return jsonify({'code': 200, 'msg': '借用成功', 'data': {'borrow_no': no}})
    except Exception as e:
        return jsonify({'code': 400, 'msg': str(e)}), 400


# --- 还库辅助：扫码查找借出记录 ---
@trans_bp.route('/return/scan', methods=['GET'])
@jwt_required()
@permission_required('op_return')
def scan_borrowed_item():
    barcode = request.args.get('barcode')
    if not barcode:
        return jsonify({'code': 400, 'msg': '无条码'}), 400

    res = TransService.scan_for_return(barcode)
    if res:
        return jsonify({'code': 200, 'data': res})
    else:
        return jsonify({'code': 404, 'msg': '未找到该物品的未还记录'}), 404


# --- 还库提交 ---
@trans_bp.route('/return', methods=['POST'])
@jwt_required()
@permission_required('op_return:operation')
def submit_return():
    data = request.get_json()
    # ★ 归还人存"姓名"，而非 JWT 数字 ID
    operator_name = _current_username()
    try:
        TransService.process_return(data, operator_name=operator_name)
        return jsonify({'code': 200, 'msg': '还库成功'})
    except Exception as e:
        return jsonify({'code': 400, 'msg': str(e)}), 400


# --- 借库报废申请（未归还 → 提交报废申请，需审批）---
@trans_bp.route('/borrow/scrap-request', methods=['POST'])
@jwt_required()
@permission_required('op_return:operation')  # 复用归还权限：能归还的库管即可申请报废
# ★ 幂等锁置于 permission_required 内层：prevent_double_submit 依赖
#   get_jwt_identity()，放外层会因 JWT 未验证而抛错、被自身 except 捕获后降级放行
@prevent_double_submit(lock_timeout=5)
def submit_borrow_scrap_request():
    """
    提交「借出未归还」的**报废申请**（需审批人审批，通过后由库管执行报废）。

    请求体:
      {
        "record_ids": [1, 2, 3],   # 必填，trans_borrow.id 列表（按整条待还量报废）
        "reason":     "物品丢失",    # 可选，写入申请单备注
        "approver_id": 7           # 必填，指定审批人
      }

    ★ 为什么改走审批：
      原先 POST /borrow/scrap 直接写 trans_scrap 并扣总库存，绕过审批，与系统
      自陈的「报废一律需审批」冲突，构成职责分离漏洞 —— 同一个库管可自行宣告
      实物损失而无人复核。现统一走：申请 → 审批 → 执行。

    ★ 执行方式：本来源为「免扫码」—— 东西在借用人手上，物理上不可能扫码；
      且执行只改台账与总库存，不产生任何可被挪用的可用库存。
    """
    data = request.get_json() or {}
    record_ids = data.get('record_ids') or []
    reason = (data.get('reason') or '').strip()
    approver_id = data.get('approver_id')

    if not record_ids:
        return jsonify({'code': 400, 'msg': '请选择要申请报废的借出记录'}), 400
    if not approver_id:
        return jsonify({'code': 400, 'msg': '请选择审批人'}), 400

    try:
        from app.models.transaction import TransBorrow

        # 逐条载入并校验。
        # ★ 已归还/已报废的**直接报错**，不静默跳过 —— 旧实现是 `continue`
        #   然后返回 count=0，用户以为成功实则什么都没发生（缺陷）。
        items = []
        missing = []
        for rid in record_ids:
            try:
                rid = int(rid)
            except (TypeError, ValueError):
                raise ValueError(f'借出记录 ID 无效：{rid}')
            record = TransBorrow.query.get(rid)
            if not record:
                missing.append(str(rid))
                continue
            if record.is_returned:
                raise ValueError(
                    f"借用记录【{record.borrow_no or rid}】已归还或已报废，不可再申请报废"
                )
            pending = (float(record.quantity or 0)
                       - float(record.returned_quantity or 0))
            if pending <= 0:
                raise ValueError(
                    f"借用记录【{record.borrow_no or rid}】无待还数量，无需报废"
                )
            items.append({
                'source_table': 'trans_borrow',
                'stock_id': record.id,
                'scrap_qty': pending,
            })

        if missing:
            raise ValueError(f'以下借出记录不存在：{"、".join(missing)}')
        if not items:
            raise ValueError('所选借出记录均无待还数量，无需报废')

        from app.services.scrap_approval_service import ScrapApprovalService

        req = ScrapApprovalService.submit_approval(
            applicant_id=get_jwt_identity(),
            items=items,
            remark=reason or None,
            approver_id=approver_id,
        )

        return jsonify({
            'code': 200,
            'msg': f'报废申请已提交（{len(items)} 条明细），待审批人审批',
            'data': {
                'request_id': req.id,
                'request_no': req.request_no,
                'count': len(items),
            },
        }), 200

    except ValueError as e:
        return jsonify({'code': 400, 'msg': str(e)}), 400
    except Exception as e:
        traceback.print_exc()
        return jsonify({'code': 500, 'msg': f'提交报废申请失败: {str(e)}'}), 500


# --- 记录列表 ---
@trans_bp.route('/records', methods=['GET'])
@jwt_required()
@permission_required('op_records')
def get_records():
    status = request.args.get('status', 'all')
    page = int(request.args.get('page', 1))
    keyword = request.args.get('keyword', '')
    search_type = request.args.get('search_type', 'all')
    start_date = request.args.get('start_date', '')
    end_date = request.args.get('end_date', '')

    # ★ 高级筛选：JSON 字符串 → 条件列表
    from app.utils.advanced_filter import parse_advanced_filters
    advanced_filters = parse_advanced_filters(request.args.get('advancedFilters', ''))

    # ★ 数据权限：普通用户只看“借用人=本人姓名(不含账号前缀)”的借还记录；管理者看全部
    borrower_name = None
    if not is_privileged_viewer():
        _identity = get_jwt_identity()
        if _identity:
            from app.models.system import SysUser
            _u = SysUser.query.get(int(_identity))
            _uname = _u.username if _u else ''
            borrower_name = _uname.split('/')[0].strip() if _uname else None

    res = TransService.get_records(
        page=page, limit=10, status=status, keyword=keyword,
        search_type=search_type, borrower_name=borrower_name,
        start_date=start_date, end_date=end_date,
        advanced_filters=advanced_filters,
    )

    # ★ service 层异常时：code==500 的字典（带 traceback），需要直通到前端，便于排查
    if isinstance(res, dict) and res.get('code') == 500:
        return jsonify({
            'code': 500,
            'msg': res.get('msg', '服务内部错误'),
            'trace': res.get('trace', '')
        }), 500

    # 字段级脱敏
    user_permissions = get_current_user_permissions()
    if res.get('items'):
        res['items'] = [filter_item_by_permissions(item, user_permissions, 'op_records') for item in res['items']]
    return jsonify({'code': 200, 'data': res})


# ==============================================================================
# 借库审批流 API（与出库审批流平行）
# ==============================================================================

# --- 提交借库申请 ---
@trans_bp.route('/borrow/request', methods=['POST'])
@jwt_required()
@permission_required('op_borrow_apply')
def submit_borrow_request():
    """
    提交借库申请（仅存储意向，不扣库存）
    请求体: { items: [...], allowed_approvers: [...], remark: '', approver_id: int }
    """
    try:
        user_id, user_role = get_current_user_info()
        if not user_id:
            return jsonify({'code': 401, 'msg': '用户未登录'}), 401

        from app.models.system import SysUser
        current_user = SysUser.query.get(user_id)
        current_username = current_user.username if current_user else None

        data = request.get_json() or {}
        items = data.get('items', [])
        if not items:
            return jsonify({'code': 400, 'msg': '借库物品列表不能为空'}), 400

        required_fields = ['name', 'spec_model', 'quantity']
        for idx, item in enumerate(items):
            missing = [f for f in required_fields if f not in item or str(item.get(f) or '').strip() == '']
            if missing:
                return jsonify({
                    'code': 400,
                    'msg': f'第{idx + 1}条物品缺少必填字段: {", ".join(missing)}'
                }), 400
            try:
                qty = float(item.get('quantity', 0))
                if qty <= 0:
                    return jsonify({'code': 400, 'msg': f'第{idx + 1}条物品的借库数量必须大于0'}), 400
            except (TypeError, ValueError):
                return jsonify({'code': 400, 'msg': f'第{idx + 1}条物品的 quantity 格式无效'}), 400

        approver_id = data.get('approver_id')
        _default_approvers = [
            {"type": "role", "value": "SUPERVISOR"},
            {"type": "role", "value": "SUPER_ADMIN"}
        ]
        allowed_approvers = data.get('allowed_approvers') or _default_approvers

        approval = BorrowApprovalService.submit_approval(
            applicant_id=user_id,
            items=items,
            allowed_approvers=allowed_approvers,
            remark=data.get('remark'),
            approver_id=approver_id,
            borrower_name=current_username,
            force_approval=((user_role or '').upper() == 'WAREHOUSE_MGR')  # 库管代建 → 强制审批
        )

        return jsonify({'code': 200, 'msg': '借库申请已提交', 'data': approval.to_dict()}), 200

    except ValueError as e:
        return jsonify({'code': 400, 'msg': str(e)}), 400
    except Exception as e:
        return jsonify({'code': 500, 'msg': f"接口内部报错: {str(e)}", 'trace': traceback.format_exc()}), 500


# --- 审批借库申请 ---
@trans_bp.route('/borrow/request/<int:request_id>/approve', methods=['PATCH'])
@jwt_required()
@permission_required('op_borrow_approval')
def approve_borrow_request(request_id):
    """
    审批借库申请
    请求体: {"action": "approve" | "reject", "reject_reason": "驳回原因"}
    """
    try:
        user_id, user_role = get_current_user_info()
        if not user_id:
            return jsonify({'code': 401, 'msg': '用户未登录'}), 401

        data = request.get_json() or {}
        action = data.get('action', 'approve')
        reject_reason = data.get('reject_reason')

        if action not in ('approve', 'reject'):
            return jsonify({'code': 400, 'msg': '无效的审批操作，仅支持 approve 或 reject'}), 400

        if action == 'reject' and not reject_reason:
            return jsonify({'code': 400, 'msg': '驳回时必须提供原因'}), 400

        success, message, approval = BorrowApprovalService.approve(
            request_id=request_id,
            user_id=user_id,
            user_role=user_role,
            action=action,
            reject_reason=reject_reason
        )

        if not success:
            return jsonify({'code': 400, 'msg': message}), 400

        return jsonify({'code': 200, 'msg': message, 'data': approval.to_dict() if approval else None}), 200

    except Exception as e:
        traceback.print_exc()
        return jsonify({'code': 500, 'msg': f'服务器内部错误: {str(e)}'}), 500


@trans_bp.route('/borrow/request/<int:request_id>/close', methods=['POST'])
@jwt_required()
@permission_required('op_borrow_approval')
def close_borrow_request(request_id):
    """
    手动完结已通过的借库审批单（status 1-已通过 → 4-已完结）
    参照出库审批的完结逻辑，供库管/主管在未走扫码借出时强制完结
    """
    try:
        user_id, _ = get_current_user_info()
        if not user_id:
            return jsonify({'code': 401, 'msg': '用户未登录'}), 401

        success, message, approval = BorrowApprovalService.mark_completed(request_id)
        if not success:
            return jsonify({'code': 400, 'msg': message}), 400

        return jsonify({'code': 200, 'msg': message, 'data': approval.to_dict() if approval else None}), 200
    except Exception as e:
        traceback.print_exc()
        return jsonify({'code': 500, 'msg': f'服务器内部错误: {str(e)}'}), 500


@trans_bp.route('/borrow/request/<int:request_id>/withdraw', methods=['POST'])
@jwt_required()
def withdraw_borrow_request(request_id):
    """
    申请人撤回自己的借库申请单（待审批 或 已通过但未执行）。

    ★ 严格职责分离：本端点**不做模块权限校验**（@jwt_required 即可），
    权限判定完全落在「单据归属」上 —— 服务层会断言
    applicant_id == 当前用户，否则 403。库管/主管可代撤。

    与 /close 的区别：/close 是管理路径（需 op_borrow_approval 权限），
    本端点是申请人路径，两者共用底层释放逻辑。
    """
    try:
        identity = get_jwt_identity()
        if not identity:
            return jsonify({'code': 401, 'msg': '用户未登录'}), 401

        success, message, approval = BorrowApprovalService.withdraw_request(
            request_id=request_id,
            user_id=int(identity),
        )

        if not success:
            code = 403 if '无权' in message else 400
            return jsonify({'code': code, 'msg': message}), code

        return jsonify({
            'code': 200,
            'msg': message,
            'data': approval.to_dict() if approval else None
        }), 200

    except Exception as e:
        traceback.print_exc()
        return jsonify({'code': 500, 'msg': f'撤回失败: {str(e)}'}), 500


# --- 借库申请预检（判断所选物料是否需审批，驱动前端是否显示审批人） ---
@trans_bp.route('/borrow/request/check-approval', methods=['POST'])
@jwt_required()
@permission_required('op_borrow_apply')
def check_borrow_approval():
    try:
        data = request.get_json() or {}
        items = data.get('items', []) or []
        from app.services.approval_control import resolve_approval_control
        need_approval, flagged = resolve_approval_control(items)
        return jsonify({
            "code": 200, "msg": "success",
            "data": {"need_approval": need_approval, "materials": flagged}
        }), 200
    except Exception as e:
        import traceback; traceback.print_exc()
        return jsonify({"code": 500, "msg": f"预检失败: {str(e)}"}), 500


# --- 获取借库审批单列表 ---
@trans_bp.route('/borrow/request', methods=['GET'])
@jwt_required()
@permission_required('op_borrow_approval')
def get_borrow_request_list():
    """
    获取借库审批单列表
    Query参数: page, limit, applicant_id, status
    """
    try:
        page = int(request.args.get('page', 1))
        limit = int(request.args.get('limit', 10))
        applicant_id = request.args.get('applicant_id')
        if applicant_id:
            applicant_id = int(applicant_id)
        status = request.args.get('status')
        if status is not None:
            status = int(status)

        # ★ 数据权限：普通申请人只能看“自己的”借还记录；库管/主管/超管(或跨域)才可看他人
        if not is_privileged_viewer():
            identity = get_jwt_identity()
            applicant_id = int(identity) if identity else None

        result = BorrowApprovalService.get_request_list(
            page=page, per_page=limit, applicant_id=applicant_id, status=status
        )

        return jsonify({'code': 200, 'msg': '获取成功', 'data': result}), 200

    except Exception as e:
        return jsonify({'code': 500, 'msg': str(e)}), 500


# --- 借库选单：库存查询（独立权限）---
@trans_bp.route('/borrow/stock-list', methods=['GET'])
@jwt_required()
@permission_required('op_borrow_apply')
def get_borrow_stock_list():
    """借库选单专用库存列表 — Fail-Closed: 剥离价格字段"""
    from app.api.v1.inbound.stock import _do_get_stock_list
    return _do_get_stock_list(permission_prefix='op_borrow_apply')


# --- 执行借库扣减（审批通过后调用）---
@trans_bp.route('/borrow/dispatch', methods=['POST'])
@jwt_required()
@prevent_double_submit(lock_timeout=5)
@permission_required('op_borrow:operation')
def dispatch_borrow():
    """
    执行借库扣减
    请求体: {
        approval_id: int,   // 关联的审批单ID
        items: [            // 扫码选中的库存物品
            {
                id: int,              // 库存主键（按 source_table 路由到 StockBuy/StockSemi/StockProduct）
                source_table: str,    // 'stock_buy' | 'stock_semi' | 'stock_product'
                sku: str,             // 可选；不参与审批上限校验
                out_quantity: float
            }
        ],
        // ★ 审批上限校验在 service 层完成：以 (name, spec_model) 为物料维度聚合
        //   锁定 stock 行后从 material_base 表取真实 (name, spec_model) 与审批单比对
        borrower_name: str,
        signature_path: str,
        remark: str,
        expected_return_time: str
    }
    """
    try:
        data = request.get_json() or {}
        approval_id = data.get('approval_id')
        if not approval_id:
            return jsonify({'code': 400, 'msg': '缺少 approval_id'}), 400

        borrow_no = TransService.execute_dispatch(
            approval_id=approval_id,
            items=data.get('items', []),
            operator_name=_current_username(),
            borrower_name=data.get('borrower_name'),
            signature=data.get('signature_path'),
            remark=data.get('remark'),
            expected_return_time=data.get('expected_return_time')
        )

        return jsonify({'code': 200, 'msg': '借库成功', 'data': {'borrow_no': borrow_no}}), 200

    except ValueError as e:
        return jsonify({'code': 400, 'msg': str(e)}), 400
    except Exception as e:
        traceback.print_exc()
        return jsonify({'code': 500, 'msg': f'服务器内部错误: {str(e)}'}), 500