{
  "title": "Graphviz JSON",
  "description": "JSON representation of a graph encoding xdot attributes",
  "type": "object",
  "properties": {
    "name": {
      "type": "string",
      "description": "The graph name"
    },
    "directed": {
      "type": "boolean",
      "description": "True if the graph is directed"
    },
    "strict": {
      "type": "boolean",
      "description": "True if the graph is strict"
    },
    "_subgraph_cnt": {
      "type": "integer",
      "description": "Number of subgraphs in the graph"
    },
    "objects": {
      "type": "array",
      "items": { "$ref": "#/definitions/metanode" },
      "description": "The graph's subgraphs followed by the graph's nodes"
    },
    "edges": {
      "type": "array",
      "items": {
        "$ref": "#/definitions/edge"
      }
    },
    "_draw_": {
      "$ref": "#/definitions/drawops"
    },
    "_ldraw_": {
      "$ref": "#/definitions/drawops"
    },
    "additionalProperties": {
      "type": "string"
    }
  },
  "required": [
    "name",
    "directed",
    "strict",
    "_subgraph_cnt"
  ],
  "definitions": {
    "edge": {
      "title": "edge",
      "type": "object",
      "properties": {
        "_gvid": {
          "type": "integer"
        },
        "tail": {
          "type": "integer",
          "description": "_gvid of tail node"
        },
        "head": {
          "type": "integer",
          "description": "_gvid of tail head"
        },
        "_draw_": {
          "$ref": "#/definitions/drawops"
        },
        "_ldraw_": {
          "$ref": "#/definitions/drawops"
        },
        "_hdraw_": {
          "$ref": "#/definitions/drawops"
        },
        "_tdraw_": {
          "$ref": "#/definitions/drawops"
        },
        "_hldraw_": {
          "$ref": "#/definitions/drawops"
        },
        "_tldraw_": {
          "$ref": "#/definitions/drawops"
        },
        "additionalProperties": {
          "type": "string"
        }
      },
      "required": [
        "_gvid",
        "tail",
        "head"
      ]
    },
    "metanode": {
      "title": "node or subgraph",
      "type": "object",
      "properties": {
        "_gvid": {
          "type": "integer"
        },
        "name": {
          "type": "string",
          "description": "The node or subgraph name"
        },
        "subgraphs": {
          "type": "array",
          "items": {
            "type": "integer"
          },
          "description": "index of a child subgraph"
        },
        "nodes": {
          "type": "array",
          "items": {
            "type": "integer"
          },
          "description": "index of a node in this subgraph"
        },
        "edges": {
          "type": "array",
          "items": {
            "type": "integer"
          },
          "description": "index of an edge in this subgraph"
        },
        "_draw_": {
          "$ref": "#/definitions/drawops"
        },
        "_ldraw_": {
          "$ref": "#/definitions/drawops"
        },
        "additionalProperties": {
          "type": "string"
        }
      },
      "required": [
        "_gvid",
        "name"
      ]
    },
    "drawops": {
      "type": "array",
      "items": {
        "oneOf": [
          {
            "$ref": "#/definitions/ellipse"
          },
          {
            "$ref": "#/definitions/polygon"
          },
          {
            "$ref": "#/definitions/polyline"
          },
          {
            "$ref": "#/definitions/bspline"
          },
          {
            "$ref": "#/definitions/text"
          },
          {
            "$ref": "#/definitions/font_style"
          },
          {
            "$ref": "#/definitions/drawcolor"
          },
          {
            "$ref": "#/definitions/font"
          },
          {
            "$ref": "#/definitions/style"
          }
        ]
      }
    },
    "ellipse": {
      "type": "object",
      "properties": {
        "op": {
          "type": "string",
          "pattern": "[eE]"
        },
        "rect": {
          "$ref": "#/definitions/rectangle"
        }
      },
      "required": [
        "op",
        "rect"
      ]
    },
    "polygon": {
      "type": "object",
      "properties": {
        "op": {
          "type": "string",
          "pattern": "[pP]"
        },
        "points": {
          "$ref": "#/definitions/pointlist"
        }
      },
      "required": [
        "op",
        "points"
      ]
    },
    "polyline": {
      "type": "object",
      "properties": {
        "op": {
          "type": "string",
          "pattern": "L"
        },
        "points": {
          "$ref": "#/definitions/pointlist"
        }
      },
      "required": [
        "op",
        "points"
      ]
    },
    "bspline": {
      "type": "object",
      "properties": {
        "op": {
          "type": "string",
          "pattern": "[bB]"
        },
        "points": {
          "$ref": "#/definitions/pointlist"
        }
      },
      "required": [
        "op",
        "points"
      ]
    },
    "text": {
      "type": "object",
      "properties": {
        "op": {
          "type": "string",
          "pattern": "T"
        },
        "pt": {
          "$ref": "#/definitions/point"
        },
        "align": {
          "type": "string",
          "pattern": "[lcr]"
        },
        "text": {
          "type": "string"
        },
        "width": {
          "type": "number"
        }
      },
      "required": [
        "op",
        "pt",
        "align",
        "text",
        "width"
      ]
    },
    "font_style": {
      "type": "object",
      "properties": {
        "op": {
          "type": "string",
          "pattern": "t"
        },
        "fontchar": {
          "type": "integer",
          "minimum": 0,
          "maximum": 127
        }
      },
      "required": [
        "op",
        "fontchar"
      ]
    },
    "drawcolor": {
      "type": "object",
      "properties": {
        "op": {
          "type": "string",
          "pattern": "[cC]"
        },
        "p0": {
          "oneOf": [
            {
              "$ref": "#/definitions/point"
            },
            {
              "$ref": "#/definitions/point3"
            }
          ]
        },
        "p1": {
          "oneOf": [
            {
              "$ref": "#/definitions/point"
            },
            {
              "$ref": "#/definitions/point3"
            }
          ]
        },
        "grad": {
          "type": "string",
          "enum": [
            "none",
            "linear",
            "radial"
          ]
        },
        "color": {
          "$ref": "#/definitions/color" 
        },
        "stops": {
          "type": "array",
          "items": {
            "$ref": "#/definitions/stop"
          }
        }
      },
      "required": [
        "op",
        "grad"
      ]
    },
    "font": {
      "type": "object",
      "properties": {
        "op": {
          "type": "string",
          "pattern": "F"
        },
        "size": {
          "type": "number",
          "minimum": 0
        },
        "face": {
          "type": "string"
        }
      },
      "required": [
        "op",
        "size",
        "face"
      ]
    },
    "style": {
      "type": "object",
      "properties": {
        "op": {
          "type": "string",
          "pattern": "S"
        },
        "style": {
          "type": "string"
        }
      },
      "required": [
        "op",
        "style"
      ]
    },
    "pointlist": {
      "type": "array",
      "items": {
        "$ref": "#/definitions/point"
      }
    },
    "point": {
      "type": "array",
      "items": {
        "type": "number"
      },
      "maxItems": 2,
      "minItems": 2
    },
    "point3": {
      "type": "array",
      "items": {
        "type": "number"
      },
      "maxItems": 3,
      "minItems": 3
    },
    "rectangle": {
      "type": "array",
      "items": {
        "type": "number"
      },
      "maxItems": 4,
      "minItems": 4
    },
    "color": {
      "type": "string",
      "pattern": "(#[0-9a-f]*)|(#[0-9a-f]{8})"
    },
    "stop": {
      "type": "object",
      "properties": {
        "frac": {
          "type": "number"
        },
        "color": {
          "$ref": "#/definitions/color"
        }
      },
      "required": [
        "frac",
        "color"
      ]
    }
  }
}