{
    "$schema": "http://json-schema.org/draft-07/schema#",
    "$id": "http://product-information-graph.org/schema/2026-02-18/jsonld/aPackage.json",
    "title": "PIG APackage JSON-LD Schema",
    "description": "Validates complete JSON-LD package documents with @context (namespace and vocabulary definitions) as well as @graph (array of PIG items). The graph contains a mix of item classes (Property, Link, Entity, Relationship) and instances (anEntity, aRelationship). Package-level metadata includes optional dcterms:modified, dcterms:creator, dcterms:title, and dcterms:description. Validates each item against its corresponding schema based on pig:itemType.",
    "type": "object",
    "properties": {
        "@context": {
            "description": "JSON-LD context defining namespaces and vocabulary mappings",
            "oneOf": [
                {
                    "type": "object",
                    "description": "Context as object with namespace mappings"
                },
                {
                    "type": "array",
                    "description": "Context as array of contexts",
                    "items": {
                        "oneOf": [
                            { "type": "object" },
                            { "type": "string" }
                        ]
                    }
                },
                {
                    "type": "string",
                    "description": "Context as URL reference"
                }
            ]
        },
        "@id": {
            "type": "string",
            "pattern": "^(?:[A-Za-z0-9_\\-]+:[^:\\s]+|https?:\\/\\/[^\\s]+)$",
            "description": "Optional package identifier"
        },
        "@type": {
            "$ref": "#/$defs/idString",
            "description": "Reference to the Package class this instance belongs to"
        },
        "pig:itemType": {
            "type": "object",
            "required": [ "@id" ],
            "properties": {
                "@id": {
                    "type": "string",
                    "enum": [ "pig:aPackage" ],
                    "description": "The PigItemType for pig:aPackage"
                }
            },
            "additionalProperties": false
        },
        "dcterms:title": {
            "type": "array",
            "description": "Optional package title",
            "minItems": 1,
            "items": {
                "$ref": "#/$defs/languageValue"
            }
        },
        "dcterms:description": {
            "type": "array",
            "description": "Optional package description",
            "minItems": 1,
            "items": {
                "$ref": "#/$defs/languageValue"
            }
        },
        "dcterms:modified": {
            "type": "string",
            "format": "date-time",
            "description": "Optional package modification timestamp"
        },
        "dcterms:creator": {
            "type": "string",
            "description": "Optional package creator"
        },
        "@graph": {
            "type": "array",
            "minItems": 0,
            "description": "Array of PIG items (classes and instances)",
            "items": {
                "type": "object",
                "required": [ "pig:itemType" ],
                "properties": {
                    "pig:itemType": {
                        "type": "object",
                        "required": [ "@id" ],
                        "properties": {
                            "@id": {
                                "type": "string",
                                "enum": [
                                    "pig:Property",
                                    "pig:Link",
                                    "pig:Entity",
                                    "pig:Relationship",
                                    "pig:anEntity",
                                    "pig:aRelationship"
                                ]
                            }
                        }
                    }
                },
                "allOf": [
                    {
                        "if": {
                            "type": "object",
                            "properties": {
                                "pig:itemType": {
									"type": "object",
                                    "properties": {
                                        "@id": { "const": "pig:anEntity" }
                                    }
                                }
                            }
                        },
                        "then": {
                            "$ref": "http://product-information-graph.org/schema/2026-02-18/jsonld/anEntity.json"
                        }
                    },
                    {
                        "if": {
                            "type": "object",
                            "properties": {
                                "pig:itemType": {
                                    "type": "object",
                                    "properties": {
                                        "@id": { "const": "pig:aRelationship" }
                                    }
                                }
                            }
                        },
                        "then": {
                            "$ref": "http://product-information-graph.org/schema/2026-02-18/jsonld/aRelationship.json"
                        }
                    },
                    {
                        "if": {
                            "type": "object",
                            "properties": {
                                "pig:itemType": {
                                    "type": "object",
                                    "properties": {
                                        "@id": { "const": "pig:Property" }
                                    }
                                }
                            }
                        },
                        "then": {
                            "$ref": "http://product-information-graph.org/schema/2026-02-18/jsonld/Property.json"
                        }
                    },
                    {
                        "if": {
                            "type": "object",
                            "properties": {
                                "pig:itemType": {
                                    "type": "object",
                                    "properties": {
                                        "@id": { "const": "pig:Link" }
                                    }
                                }
                            }
                        },
                        "then": {
                            "$ref": "http://product-information-graph.org/schema/2026-02-18/jsonld/Link.json"
                        }
                    },
                    {
                        "if": {
                            "type": "object",
                            "properties": {
                                "pig:itemType": {
                                    "type": "object",
                                    "properties": {
                                        "@id": { "const": "pig:Entity" }
                                    }
                                }
                            }
                        },
                        "then": {
                            "$ref": "http://product-information-graph.org/schema/2026-02-18/jsonld/Entity.json"
                        }
                    },
                    {
                        "if": {
                            "type": "object",
                            "properties": {
                                "pig:itemType": {
                                    "type": "object",
                                    "properties": {
                                        "@id": { "const": "pig:Relationship" }
                                    }
                                }
                            }
                        },
                        "then": {
                            "$ref": "http://product-information-graph.org/schema/2026-02-18/jsonld/Relationship.json"
                        }
                    }
                ]
            }
        }
    },
    "required": [ "@context", "@graph" ],
    "additionalProperties": true,
  "$defs": {
    "idString": {
      "type": "string",
      "pattern": "^(?:[A-Za-z0-9_\\-]+:[^:\\s]+|https?:\\/\\/[^\\s]+)$",
      "description": "Valid identifier format: namespace:name or full URI (e.g., 'pig:Property', 'http://example.org/id')"
    },
    "languageValue": {
      "type": "object",
      "required": [ "@value" ],
      "properties": {
        "@value": {
          "type": "string",
          "minLength": 1,
          "description": "The actual text content"
        },
        "@language": {
          "type": "string",
          "pattern": "^[a-z]{2}(-[A-Z]{2})?$",
          "description": "IETF language tag (e.g., 'en', 'de', 'en-US')"
        }
      },
      "additionalProperties": false,
      "description": "Multi-language text value with optional language tag"
    }
  }
}