{
    "$schema": "http://json-schema.org/draft-07/schema#",
    "$id": "https://example.com/wh-telemetry.schema.json",
    "title": "WH Telemetry Protocol v1 Message",
    "description": "JSON Schema definition for a WH Telemetry Protocol (WHTP) telemetry message.",
    "type": "object",
    "additionalProperties": false,
    "required": [
        "version",
        "msg_type",
        "dev_id",
        "dev_type",
        "timestamp",
        "fields"
    ],
    "properties": {
        "version": {
            "type": "integer",
            "const": 1,
            "description": "Protocol major version, currently fixed to 1."
        },
        "msg_type": {
            "type": "string",
            "const": "telemetry",
            "description": "Message type, only 'telemetry' is supported for now."
        },
        "mode": {
            "type": "string",
            "enum": [
                "descriptive",
                "strict"
            ],
            "description": "Operating mode of the message."
        },
        "dev_id": {
            "type": "string",
            "format": "nanoid",
            "description": "Device unique identifier (NanoID).",
            "pattern": "^[A-Za-z0-9_-]{21}$"
        },
        "dev_type": {
            "description": "Device model identifier.",
            "oneOf": [
                {
                    "type": "string"
                },
                {
                    "type": "object",
                    "oneOf": [
                        {
                            "required": [
                                "type_id"
                            ],
                            "properties": {
                                "type_id": {
                                    "type": "string",
                                    "format": "nanoid",
                                    "pattern": "^[A-Za-z0-9_-]{21}$"
                                }
                            },
                            "additionalProperties": false
                        },
                        {
                            "required": [
                                "type_name"
                            ],
                            "properties": {
                                "type_name": {
                                    "type": "string"
                                }
                            },
                            "additionalProperties": false
                        }
                    ]
                }
            ]
        },
        "timestamp": {
            "$ref": "#/definitions/Timestamp"
        },
        "fields": {
            "type": "array",
            "minItems": 1,
            "items": {
                "$ref": "#/definitions/Field"
            }
        },
        "metadata": {
            "$ref": "#/definitions/MessageMetadata"
        }
    },
    "definitions": {
        "Timestamp": {
            "description": "Flexible timestamp supporting multiple formats.",
            "oneOf": [
                {
                    "type": "number"
                },
                {
                    "type": "object",
                    "additionalProperties": false,
                    "oneOf": [
                        {
                            "required": [
                                "unix_s"
                            ],
                            "properties": {
                                "unix_s": {
                                    "type": "number"
                                }
                            }
                        },
                        {
                            "required": [
                                "unix_ms"
                            ],
                            "properties": {
                                "unix_ms": {
                                    "type": "number"
                                }
                            }
                        },
                        {
                            "required": [
                                "unix_us"
                            ],
                            "properties": {
                                "unix_us": {
                                    "type": "number"
                                }
                            }
                        },
                        {
                            "required": [
                                "unix_ns"
                            ],
                            "properties": {
                                "unix_ns": {
                                    "type": "number"
                                }
                            }
                        },
                        {
                            "required": [
                                "iso8601"
                            ],
                            "properties": {
                                "iso8601": {
                                    "type": "string",
                                    "format": "date-time"
                                }
                            }
                        }
                    ]
                }
            ]
        },
        "SampleInterval": {
            "oneOf": [
                {
                    "type": "number"
                },
                {
                    "type": "object",
                    "additionalProperties": false,
                    "minProperties": 1,
                    "properties": {
                        "ms": {
                            "type": "number",
                            "minimum": 0
                        },
                        "s": {
                            "type": "number",
                            "minimum": 0
                        },
                        "m": {
                            "type": "number",
                            "minimum": 0
                        },
                        "h": {
                            "type": "number",
                            "minimum": 0
                        },
                        "d": {
                            "type": "number",
                            "minimum": 0
                        },
                        "w": {
                            "type": "number",
                            "minimum": 0
                        }
                    }
                }
            ]
        },
        "Confidence": {
            "oneOf": [
                {
                    "type": "number",
                    "minimum": 0,
                    "maximum": 1
                },
                {
                    "type": "array",
                    "items": {
                        "type": "number",
                        "minimum": 0,
                        "maximum": 1
                    }
                }
            ]
        },
        "InlineEnum": {
            "type": "object",
            "minProperties": 1,
            "patternProperties": {
                "^[A-Za-z_][A-Za-z0-9_]*$": {
                    "type": "number"
                }
            },
            "additionalProperties": false
        },
        "FieldMetadata": {
            "type": "object",
            "description": "Metadata describing a field value.",
            "required": [
                "data_type"
            ],
            "properties": {
                "data_type": {
                    "type": "string"
                },
                "timestamp": {
                    "$ref": "#/definitions/Timestamp"
                },
                "sample_interval": {
                    "$ref": "#/definitions/SampleInterval"
                },
                "unit": {
                    "type": "string"
                },
                "label": {
                    "type": "string"
                },
                "confidence": {
                    "$ref": "#/definitions/Confidence"
                },
                "error_code": {
                    "type": "integer",
                    "minimum": 0
                },
                "error_msg": {
                    "type": "string"
                },
                "enum": {
                    "$ref": "#/definitions/InlineEnum"
                },
                "user": {
                    "type": "object",
                    "additionalProperties": true
                }
            },
            "additionalProperties": false
        },
        "Field": {
            "type": "object",
            "description": "Single telemetry measurement field.",
            "required": [
                "id",
                "value",
                "metadata"
            ],
            "properties": {
                "id": {
                    "type": "string",
                    "pattern": "^[A-Za-z_][A-Za-z0-9_]*$"
                },
                "value": {
                    "oneOf": [
                        {
                            "type": [
                                "string",
                                "number",
                                "boolean"
                            ]
                        },
                        {
                            "type": "array"
                        },
                        {
                            "type": "object"
                        }
                    ]
                },
                "metadata": {
                    "$ref": "#/definitions/FieldMetadata"
                }
            },
            "additionalProperties": false
        },
        "EnumDefinition": {
            "type": "object",
            "required": [
                "id",
                "value"
            ],
            "properties": {
                "id": {
                    "type": "string"
                },
                "value": {
                    "$ref": "#/definitions/InlineEnum"
                }
            },
            "additionalProperties": false
        },
        "Location": {
            "type": "object",
            "required": [
                "coordinates"
            ],
            "properties": {
                "coordinates": {
                    "type": "array",
                    "items": {
                        "type": "number"
                    },
                    "minItems": 2,
                    "maxItems": 2
                },
                "coordinate_system": {
                    "type": "string",
                    "enum": [
                        "wgs84",
                        "gcj02",
                        "bd09"
                    ]
                },
                "accuracy": {
                    "type": "number",
                    "minimum": 0
                },
                "altitude": {
                    "type": "number"
                }
            },
            "additionalProperties": false
        },
        "MessageMetadata": {
            "type": "object",
            "properties": {
                "enums": {
                    "type": "array",
                    "items": {
                        "$ref": "#/definitions/EnumDefinition"
                    }
                },
                "location": {
                    "$ref": "#/definitions/Location"
                },
                "battery": {
                    "type": "number",
                    "minimum": 0,
                    "maximum": 100
                },
                "seq": {
                    "type": "integer",
                    "minimum": 0
                },
                "user": {
                    "type": "object",
                    "additionalProperties": true
                }
            },
            "additionalProperties": false
        }
    }
}