{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://bdekoz.github.io/cartofreako/contracts/projection-fixtures-v1.schema.json",
  "title": "Cartofreako implementation-neutral projection fixtures v1",
  "type": "object",
  "required": [
    "schemaVersion",
    "family",
    "coordinateContract",
    "layouts"
  ],
  "additionalProperties": false,
  "properties": {
    "schemaVersion": { "const": "cartofreako-projection-fixtures-v1" },
    "family": {
      "enum": [
        "cahill-keyes",
        "authagraph",
        "dymaxion",
        "myriahedral",
        "star-x",
        "voronoi"
      ]
    },
    "coordinateContract": {
      "type": "object",
      "required": ["geographic", "projected", "origin", "xAxis", "yAxis"],
      "properties": {
        "geographic": { "const": "[longitude, latitude] degrees" },
        "projected": { "const": "[u, v] normalized page coordinates" },
        "origin": { "const": "top-left" },
        "xAxis": { "const": "right" },
        "yAxis": { "const": "down" }
      },
      "additionalProperties": false
    },
    "layouts": {
      "type": "array",
      "minItems": 1,
      "items": { "$ref": "#/$defs/layout" }
    }
  },
  "$defs": {
    "pair": {
      "type": "array",
      "prefixItems": [{ "type": "number" }, { "type": "number" }],
      "items": false
    },
    "candidate": {
      "type": "object",
      "required": [
        "geographic",
        "topologyKey",
        "component",
        "boundary"
      ],
      "properties": {
        "geographic": { "$ref": "#/$defs/pair" },
        "topologyKey": { "type": "string", "minLength": 1 },
        "component": { "type": "integer", "minimum": 0 },
        "boundary": { "type": "boolean" }
      },
      "additionalProperties": false
    },
    "case": {
      "type": "object",
      "required": [
        "caseId",
        "operation",
        "input",
        "expected",
        "boundaryClass",
        "tolerances",
        "evidence"
      ],
      "properties": {
        "caseId": { "type": "string", "minLength": 1 },
        "operation": { "const": "forward-reverse" },
        "input": {
          "type": "object",
          "required": ["geographic"],
          "properties": { "geographic": { "$ref": "#/$defs/pair" } },
          "additionalProperties": false
        },
        "expected": {
          "type": "object",
          "required": [
            "projected",
            "topologyKey",
            "component",
            "reverseStatus",
            "reverseCandidates"
          ],
          "properties": {
            "projected": { "$ref": "#/$defs/pair" },
            "topologyKey": { "type": "string", "minLength": 1 },
            "component": { "type": "integer", "minimum": 0 },
            "reverseStatus": {
              "enum": ["unique", "ambiguous", "outside", "cut", "unsupported"]
            },
            "reverseCandidates": {
              "type": "array",
              "items": { "$ref": "#/$defs/candidate" }
            }
          },
          "additionalProperties": false
        },
        "boundaryClass": {
          "enum": ["interior", "edge", "vertex", "cut", "pole", "overlap"]
        },
        "tolerances": {
          "type": "object",
          "required": ["angularDegrees", "normalizedPlanar"],
          "properties": {
            "angularDegrees": { "type": "number", "exclusiveMinimum": 0 },
            "normalizedPlanar": { "type": "number", "exclusiveMinimum": 0 }
          },
          "additionalProperties": false
        },
        "evidence": {
          "type": "object",
          "required": ["grade", "source", "revision"],
          "properties": {
            "grade": {
              "enum": [
                "published-anchor",
                "upstream-implementation",
                "independent-reimplementation",
                "structural-invariant",
                "cartofreako-compatibility"
              ]
            },
            "source": { "type": "string", "minLength": 1 },
            "revision": { "type": "integer", "minimum": 1 }
          },
          "additionalProperties": false
        }
      },
      "additionalProperties": false
    },
    "layout": {
      "type": "object",
      "required": [
        "layoutId",
        "nativeAspect",
        "componentModel",
        "cutTopology",
        "cases"
      ],
      "properties": {
        "layoutId": { "type": "string", "minLength": 1 },
        "nativeAspect": { "type": "number", "exclusiveMinimum": 0 },
        "componentModel": { "type": "string", "minLength": 1 },
        "cutTopology": { "type": "string", "minLength": 1 },
        "cases": {
          "type": "array",
          "minItems": 1,
          "items": { "$ref": "#/$defs/case" }
        }
      },
      "additionalProperties": false
    }
  }
}