{
  "type": "object",
  "properties": {
    "conditions": {
      "type": "object",
      "properties": {
        "children": {
          "type": "array",
          "items": {
            "$ref": "#/properties/conditions"
          },
          "title": "子条件",
          "description": "子条件节点，递归结构"
        },
        "exprs": {
          "type": "array",
          "items": {
            "type": "object",
            "properties": {
              "column": {
                "type": "string",
                "title": "字段编码"
              },
              "columnResource": {
                "type": "string",
                "title": "所属资源",
                "description": "字段所属资源标识，取值为顶层 resource 或 relations[].code"
              },
              "columnSqlFunc": {
                "type": "string",
                "title": "列SQL函数",
                "description": "对列应用 SQL 函数后再参与比较，拼接为 {func}({columnResource}.{column}) {operator} {value}。\r\n支持 SQL-92 / SQL:1999 / SQL:2003 标准函数及数据库方言函数，如 DATE、UPPER、ROUND。\r\n需要第二参数的函数（如 ROUND、CAST）配合 columnSqlFuncParam 使用。"
              },
              "columnSqlFuncParam": {
                "type": "string",
                "title": "列SQL函数参数",
                "description": "columnSqlFunc 的附加参数，按函数类型用途不同：\r\r通用函数（有 param 时）：{func}({columnResource}.{column}, {columnSqlFuncParam}) {operator} {value}\r  示例：ROUND(col, 2) → columnSqlFuncParam=\"2\"\r        SUBSTRING(col, 1, 10) → columnSqlFuncParam=\"1, 10\"\r\rJSON 函数（param 为 JSON 路径表达式）：\r  json_member_of（value 是否是列 JSON 数组的成员）：\r    无 param：JSON_CONTAINS({value}, JSON_ARRAY({column}))\r    有 param：JSON_CONTAINS({columnSqlFuncParam}, JSON_ARRAY({column}))\r  json_contains（列 JSON 是否包含 value）：\r    无 param：JSON_CONTAINS({column}, JSON_ARRAY({value}))\r    有 param：JSON_CONTAINS({columnSqlFuncParam}, JSON_ARRAY({value}))"
              },
              "ignoreEmptyParam": {
                "type": "boolean",
                "title": "忽略空参数",
                "description": "当 valueType=param 且请求参数值为空（空字符串或 null）时，跳过该条件不生成 SQL。用于实现可选过滤项",
                "default": false
              },
              "operator": {
                "type": "string",
                "title": "运算符",
                "description": "标准 SQL 比较运算符：\r\n= / != / \u003e / \u003e= / \u003c / \u003c=\r\nLIKE：模糊匹配（%keyword%）\r\nIN：包含，value 逗号分隔多值\r\nIS NULL / IS NOT NULL：空值判断，无需 value\r\nREGEXP：正则匹配",
                "default": "="
              },
              "value": {
                "type": "string",
                "title": "比较值",
                "description": "比较目标，内容由 valueType 决定。operator 为 IS NULL/IS NOT NULL 时可省略"
              },
              "valueType": {
                "type": "string",
                "title": "比较值类型",
                "description": "先选类型再填 value：\r\nstring：value 填字面量如 '2024-01-01'\r\nfunc：value 填内置函数名 UserID|UserUuid|UserRolesUuid|UserPlatform|UserSaaS\r\nparam：value 填请求参数路径如 body.status\r\nsql：value 填原始SQL如 CURRENT_DATE",
                "default": "string",
                "enum": [
                  "string",
                  "func"
                ]
              }
            },
            "title": "_items",
            "description": "_items",
            "required": [
              "column",
              "operator"
            ]
          },
          "title": "条件表达式列表",
          "description": "当前层的叶子比较列表，每项生成一个 column {operator} value 片段，同层多项以 type 连接"
        },
        "type": {
          "type": "string",
          "title": "逻辑连接符",
          "description": "当前节点的逻辑运算符，将 exprs 各项与 children 各组以 AND 或 OR 连接",
          "default": "and",
          "enum": [
            "and",
            "or"
          ]
        }
      },
      "title": "树形查询条件",
      "description": "WHERE 条件树。\rexprs 每项生成一段比较：[{columnSqlFunc}(]{columnResource}.{column}[)] {operator} {value}，同层多项以 type(and/or) 连接；\rchildren 为同结构子节点，递归嵌套实现复杂过滤。",
      "required": [
        "exprs",
        "type"
      ]
    },
    "fields": {
      "type": "array",
      "items": {
        "oneOf": [
          {
            "type": "string",
            "title": "字段编码",
            "description": "字段引用，格式：{columnResource}.{column} 或 {column}"
          },
          {
            "type": "object",
            "properties": {
              "alias": {
                "type": "string",
                "title": "别名"
              },
              "expr": {
                "type": "string",
                "title": "SQL 表达式",
                "description": "SQL 表达式：如 COUNT(*) / SUM(amount)\r{column}：字段编码，默认归属顶层 resource\r{columnResource}.{column}：显式指定资源的字段引用"
              }
            },
            "title": "表达式字段"
          },
          {
            "type": "object",
            "properties": {
              "alias": {
                "type": "string",
                "title": "别名"
              },
              "column": {
                "type": "string",
                "title": "字段编码"
              },
              "columnResource": {
                "type": "string",
                "title": "所属资源",
                "description": "字段所属资源标识，取值为顶层 resource 或 relations[].code"
              }
            },
            "title": "资源字段",
            "required": [
              "column"
            ]
          }
        ]
      },
      "title": "查询字段",
      "description": "查询字段，不传则返回所有字段"
    },
    "groupBy": {
      "type": "array",
      "items": {
        "oneOf": [
          {
            "type": "string",
            "title": "分组表达式",
            "description": "SQL 表达式：如 COUNT(*) / SUM(amount)\r{column}：字段编码，默认归属顶层 resource\r{columnResource}.{column}：显式指定资源的字段引用"
          },
          {
            "type": "object",
            "properties": {
              "column": {
                "type": "string",
                "title": "字段编码"
              },
              "columnResource": {
                "type": "string",
                "title": "所属资源",
                "description": "字段所属资源标识，取值为顶层 resource 或 relations[].code"
              }
            },
            "title": "资源字段",
            "required": [
              "column"
            ]
          }
        ]
      },
      "title": "分组规则",
      "description": "GROUP BY 字段列表，配合 fields 中的聚合字段使用"
    },
    "limit": {
      "type": "integer",
      "title": "每页条数",
      "description": "返回的最大记录数",
      "default": 30
    },
    "offset": {
      "type": "integer",
      "title": "偏移量",
      "description": "跳过的记录数",
      "default": 0
    },
    "orderBy": {
      "type": "array",
      "items": {
        "oneOf": [
          {
            "type": "string",
            "title": "SQL 表达式 (ASC)",
            "description": "SQL 表达式：如 COUNT(*) / SUM(amount)\r{column}：字段编码，默认归属顶层 resource\r{columnResource}.{column}：显式指定资源的字段引用\r默认升序（asc）"
          },
          {
            "type": "object",
            "properties": {
              "direction": {
                "type": "string",
                "title": "排序方向",
                "default": "asc",
                "enum": [
                  "asc",
                  "desc"
                ]
              },
              "expr": {
                "type": "string",
                "title": "SQL 表达式",
                "description": "SQL 表达式：如 COUNT(*) / SUM(amount)\r{column}：字段编码，默认归属顶层 resource\r{columnResource}.{column}：显式指定资源的字段引用"
              }
            },
            "title": "SQL 表达式排序"
          },
          {
            "type": "object",
            "properties": {
              "column": {
                "type": "string",
                "title": "字段编码"
              },
              "columnResource": {
                "type": "string",
                "title": "所属资源"
              },
              "direction": {
                "type": "string",
                "title": "排序方向",
                "default": "asc",
                "enum": [
                  "asc",
                  "desc"
                ]
              }
            },
            "title": "资源字段排序",
            "required": [
              "column",
              "columnResource"
            ]
          }
        ]
      },
      "title": "排序规则",
      "description": "排序规则列表，多项按顺序依次应用"
    },
    "relations": {
      "type": "array",
      "items": {
        "type": "object",
        "properties": {
          "actuallyField": {
            "type": "string",
            "title": "实际资源字段",
            "description": "目标资源（code）参与 ON 条件的字段"
          },
          "actuallyResource": {
            "type": "string",
            "title": "实际资源",
            "description": "被关联的目标资源编码（相当于 SQL 表名）。JOIN 拼接为：{type} JOIN {actuallyResource} AS {code} ON {code}.{actuallyField} = {relationResource}.{relationField}"
          },
          "code": {
            "type": "string",
            "title": "关联标识",
            "description": "关联唯一标识，同时作为别名：JOIN 时为表别名（AS code），子查询时为结果 JSON 字段的键名"
          },
          "conditions": {
            "$ref": "#/properties/conditions"
          },
          "groupBy": {
            "$ref": "#/properties/groupBy"
          },
          "limit": {
            "$ref": "#/properties/limit"
          },
          "name": {
            "type": "string",
            "title": "关联名称",
            "description": "关联的显示名称"
          },
          "orderBy": {
            "$ref": "#/properties/orderBy"
          },
          "relationField": {
            "type": "string",
            "title": "被关联资源字段",
            "description": "ON 条件对端资源的字段"
          },
          "relationResource": {
            "type": "string",
            "title": "被关联资源",
            "description": "ON 条件对端的资源编码（通常为主资源或父关联资源）"
          },
          "type": {
            "type": "string",
            "title": "关联类型",
            "description": "关联模式：\r\ninner / left / right：SQL JOIN，将关联资源字段合并到主查询行\r\nhasOne：子查询，关联结果聚合为单个对象（result[code] = {}）\r\nhasMany：子查询，关联结果聚合为对象数组（result[code] = [...]）",
            "enum": [
              "inner",
              "left",
              "right",
              "hasOne",
              "hasMany"
            ]
          }
        },
        "required": [
          "actuallyField",
          "actuallyResource",
          "code",
          "relationField",
          "relationResource",
          "type"
        ]
      },
      "title": "资源关联",
      "description": "关联配置列表，支持 JOIN（inner / left / right）将关联字段合并到主查询，或子查询（hasOne / hasMany）将关联数据聚合为独立 JSON 字段"
    }
  }
}