{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://opendataproducts.org/odpg-v1.0/schema/graph.json",
  "title": "Open Data Product Graphs Schema",
  "description": "Schema for Open Data Product Graphs (ODPG) v1.0 graph documents.",
  "type": "object",
  "additionalProperties": false,
  "patternProperties": {
    "^x-": {}
  },
  "required": [
    "schema",
    "version",
    "kind",
    "id",
    "name",
    "nodes",
    "edges"
  ],
  "properties": {
    "schema": {
      "type": "string",
      "format": "uri",
      "description": "URL of the ODPG schema used for validation.",
      "examples": [
        "https://opendataproducts.org/odpg-v1.0/schema/graph.yaml"
      ]
    },
    "version": {
      "oneOf": [
        {
          "type": "string"
        },
        {
          "type": "number"
        }
      ],
      "description": "Version of the ODPG specification.",
      "examples": [
        "1.0",
        1.0
      ]
    },
    "kind": {
      "type": "string",
      "const": "DataProductGraph",
      "description": "Type of graph specification document."
    },
    "id": {
      "type": "string",
      "minLength": 1,
      "description": "Unique identifier of the graph."
    },
    "name": {
      "$ref": "#/$defs/LocalizedText",
      "description": "Human-readable graph name."
    },
    "metadata": {
      "$ref": "#/$defs/Metadata"
    },
    "nodes": {
      "type": "array",
      "description": "Collection of graph nodes.",
      "minItems": 0,
      "uniqueItems": true,
      "items": {
        "$ref": "#/$defs/Node"
      }
    },
    "edges": {
      "type": "array",
      "description": "Collection of directional graph edges.",
      "minItems": 0,
      "items": {
        "$ref": "#/$defs/Edge"
      }
    }
  },
  "$defs": {
    "LocalizedText": {
      "type": "object",
      "description": "Localized text values keyed by ISO 639-1 two-letter language code.",
      "minProperties": 1,
      "additionalProperties": false,
      "patternProperties": {
        "^[a-z]{2}$": {
          "type": "string",
          "minLength": 1
        }
      }
    },
    "Owner": {
      "type": "object",
      "additionalProperties": false,
      "patternProperties": {
        "^x-": {}
      },
      "required": [
        "name"
      ],
      "properties": {
        "name": {
          "type": "string",
          "minLength": 1,
          "description": "Name of the owning person, team, or organization."
        },
        "email": {
          "type": "string",
          "format": "email",
          "description": "Contact email for the owning party."
        }
      }
    },
    "Metadata": {
      "type": "object",
      "description": "Optional metadata block for describing graph purpose, ownership, visibility, and discovery information.",
      "additionalProperties": false,
      "patternProperties": {
        "^x-": {}
      },
      "properties": {
        "name": {
          "$ref": "#/$defs/LocalizedText"
        },
        "description": {
          "$ref": "#/$defs/LocalizedText"
        },
        "domain": {
          "$ref": "#/$defs/LocalizedText"
        },
        "purpose": {
          "$ref": "#/$defs/LocalizedText"
        },
        "tags": {
          "type": "array",
          "description": "Keywords used for discovery, filtering, grouping, and search.",
          "items": {
            "type": "string"
          }
        },
        "status": {
          "type": "string",
          "description": "Current status of the graph.",
          "enum": [
            "draft",
            "active",
            "deprecated",
            "archived"
          ]
        },
        "visibility": {
          "type": "string",
          "description": "Intended visibility of the graph.",
          "enum": [
            "public",
            "internal",
            "restricted",
            "private"
          ]
        },
        "owner": {
          "$ref": "#/$defs/Owner"
        }
      }
    },
    "Node": {
      "type": "object",
      "description": "A distinct entity participating in the graph ecosystem.",
      "additionalProperties": false,
      "patternProperties": {
        "^x-": {}
      },
      "required": [
        "id",
        "type",
        "$ref"
      ],
      "properties": {
        "id": {
          "type": "string",
          "minLength": 1,
          "description": "Unique identifier of the node."
        },
        "type": {
          "type": "string",
          "minLength": 1,
          "description": "Type of graph entity represented by the node.",
          "examples": [
            "DataProduct",
            "UseCase",
            "BusinessObjective",
            "KPI",
            "Domain",
            "Dataset",
            "API",
            "Policy",
            "Workflow",
            "Agent",
            "Capability",
            "StrategicOpportunity"
          ]
        },
        "$ref": {
          "type": "string",
          "minLength": 1,
          "description": "Path or URI to the referenced specification or resource."
        }
      }
    },
    "Edge": {
      "type": "object",
      "description": "A directional relationship connecting two graph nodes.",
      "additionalProperties": false,
      "patternProperties": {
        "^x-": {}
      },
      "required": [
        "from",
        "to",
        "type",
        "confidence"
      ],
      "properties": {
        "from": {
          "type": "string",
          "minLength": 1,
          "description": "Source node identifier."
        },
        "to": {
          "type": "string",
          "minLength": 1,
          "description": "Target node identifier."
        },
        "type": {
          "type": "string",
          "minLength": 1,
          "description": "Relationship type.",
          "examples": [
            "uses",
            "supports",
            "contributesTo",
            "measures",
            "tracks",
            "dependsOn",
            "produces",
            "consumes",
            "governedBy",
            "ownedBy",
            "alignsWith",
            "relatedTo",
            "impacts",
            "derivedFrom",
            "exposes",
            "monitors",
            "identifies"
          ]
        },
        "confidence": {
          "type": "string",
          "description": "Confidence level of the relationship.",
          "enum": [
            "high",
            "medium",
            "low"
          ]
        }
      }
    }
  }
}