{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://dpworld/schemas/protocol_v3.json",
  "title": "Protocol configuration (schema v3 — nested 재설계)",
  "description": "Web Configurator ↔ dpworldapp 옵션 C. v2 의 정규화 + Nested grouping. ★ 큰 BC break. future ideal.",
  "type": "object",
  "required": ["schema_version", "device", "protocol"],
  "additionalProperties": false,
  "properties": {
    "schema_version": {"type": "integer", "const": 3},

    "device": {
      "type": "object",
      "required": ["type"],
      "additionalProperties": false,
      "properties": {
        "type": {"type": "string", "enum": ["RTLS"], "description": "디바이스 종류."},
        "version": {"type": "string", "pattern": "^v\\d+\\.\\d+(\\.\\d+)?$", "default": "v1.0"},
        "equipment": {
          "type": "object",
          "additionalProperties": false,
          "properties": {
            "type": {"type": "string", "enum": ["ITV","FL","CR"]},
            "id": {"type": "string", "pattern": "^\\d{2}$"},
            "meid": {"type": "integer", "minimum": 0}
          }
        }
      }
    },

    "protocol": {
      "type": "string",
      "enum": ["OPC-UA", "MODBUS", "CAN-BUS", "NONE"],
      "description": "활성 protocol."
    },

    "features": {
      "type": "object",
      "additionalProperties": false,
      "description": "On/Off 기능 토글 — v2 의 dr_on/odo_on 등 boolean fields 그룹화.",
      "properties": {
        "dr": {"type": "boolean", "default": true, "description": "Dead Reckoning."},
        "odo": {"type": "boolean", "default": false, "description": "Odometer."},
        "heading": {"type": "boolean", "default": true, "description": "Heading 계산."},
        "heading_imu": {"type": "boolean", "default": false, "description": "IMU 기반 heading."},
        "fix_mode": {"type": "boolean", "default": true, "description": "Fix mode."},
        "can_input": {"type": "boolean", "default": false, "description": "CAN 입력."}
      }
    },

    "speed_data": {
      "type": "string",
      "enum": ["CAN", "HW", "OPC-UA", "MODBUS"],
      "description": "속도 데이터 source."
    },

    "byte_order": {
      "type": "object",
      "additionalProperties": false,
      "description": "v2 의 two_byte_order / four_byte_order 통합 그룹.",
      "properties": {
        "two_byte": {"type": "string", "enum": ["big","little"], "default": "big"},
        "four_byte": {"type": "string", "enum": ["big","little","bigSwap","littleSwap"], "default": "big"}
      }
    },

    "analog_input": {
      "type": "object",
      "additionalProperties": false,
      "description": "Analog input level + ai0~ai3.",
      "properties": {
        "level": {"type": "string", "enum": ["2","4","6"]},
        "enabled": {
          "type": "array",
          "minItems": 4,
          "maxItems": 4,
          "description": "ai0~ai3 활성 여부 (boolean 4개).",
          "items": {"type": "boolean"}
        }
      }
    },

    "digital_input": {
      "type": "object",
      "additionalProperties": false,
      "properties": {
        "enabled": {
          "type": "array",
          "minItems": 4,
          "maxItems": 4,
          "description": "di0~di3 활성 여부.",
          "items": {"type": "boolean"}
        }
      }
    },

    "odo": {
      "type": "object",
      "additionalProperties": false,
      "description": "Odometer 설정.",
      "properties": {
        "speed": {"$ref": "#/$defs/OdoField"},
        "direction": {"$ref": "#/$defs/OdoField"}
      }
    },

    "registers": {
      "type": "object",
      "additionalProperties": false,
      "description": "v2 의 OPC_UA/CAN/MODBUS upper-case array → lowercase nested 그룹.",
      "properties": {
        "opc_ua": {"type": "array", "items": {"$ref": "#/$defs/OpcUaRegister"}},
        "can": {"type": "array", "items": {"$ref": "#/$defs/CanRegister"}},
        "modbus": {"type": "array", "items": {"$ref": "#/$defs/ModbusRegister"}}
      }
    }
  },

  "$defs": {
    "OdoField": {
      "type": "object",
      "required": ["source"],
      "additionalProperties": false,
      "properties": {
        "source": {"type": "string", "enum": ["CAN","HW","OPC-UA","MODBUS"]},
        "id": {"type": "string", "pattern": "^0x[0-9a-fA-F]+$"},
        "shift": {"type": "integer", "minimum": 0, "maximum": 63},
        "mask": {"type": "string", "pattern": "^0x[0-9a-fA-F]+$"},
        "expr": {"type": "string", "maxLength": 256}
      }
    },
    "OpcUaRegister": {
      "type": "object",
      "required": ["field","ns","addr","odt"],
      "additionalProperties": false,
      "properties": {
        "field": {"type": "string"},
        "ns": {"type": "integer", "minimum": 0},
        "addr": {"type": "integer", "minimum": 0},
        "odt": {"type": "string", "enum": ["integer","float","float64","boolean","string"]},
        "dv": {"type": "integer"},
        "expr": {"type": "string", "maxLength": 256}
      }
    },
    "CanRegister": {
      "type": "object",
      "required": ["field","id","shift","mask","odt"],
      "additionalProperties": false,
      "properties": {
        "field": {"type": "string"},
        "id": {"type": "string", "pattern": "^0x[0-9a-fA-F]+$"},
        "shift": {"type": "integer", "minimum": 0, "maximum": 63},
        "mask": {"type": "string", "pattern": "^0x[0-9a-fA-F]+$"},
        "odt": {"type": "string", "enum": ["integer","float","float64","boolean","string"]},
        "dv": {"type": "integer"},
        "expr": {"type": "string", "maxLength": 256}
      }
    },
    "ModbusRegister": {
      "type": "object",
      "required": ["field","addr","odt"],
      "additionalProperties": false,
      "properties": {
        "field": {"type": "string"},
        "addr": {"type": "integer", "minimum": 0},
        "odt": {"type": "string", "enum": ["integer","float","float64","boolean","string"]},
        "dv": {"type": "integer"},
        "expr": {"type": "string", "maxLength": 256}
      }
    }
  }
}