{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "urn:showpapers:reading:1",
  "title": "Reading",
  "$comment": "readings/<id>.json: the app's on-device reading of one original (OCR pages, blocks, lines, optional words, normalized regions and confidences) and the reader's result JSON. Text limits are UTF-8 bytes: page 262144, block 65536, line 8192, word 2048. Page indexes are unique. Together with the paper record it must fit the apps' analysis store (50,000 nodes, 2 MiB). sdkAnalysis is ShowPapers-internal: copy it unchanged or set it to null; never edit it.",
  "type": "object",
  "additionalProperties": false,
  "required": [
    "readingVersion",
    "extractorVersion",
    "concerns",
    "pages",
    "sdkAnalysis"
  ],
  "properties": {
    "readingVersion": {
      "const": 1,
      "type": "integer"
    },
    "extractorVersion": {
      "type": "integer",
      "minimum": 1,
      "maximum": 100000
    },
    "concerns": {
      "type": "array",
      "maxItems": 5,
      "uniqueItems": true,
      "items": {
        "enum": [
          "no-text",
          "unrecognized-document",
          "conflicting-document-types",
          "no-supported-fields",
          "field-limit-reached"
        ]
      }
    },
    "pages": {
      "type": "array",
      "maxItems": 200,
      "items": {
        "$ref": "#/$defs/page"
      }
    },
    "sdkAnalysis": {
      "anyOf": [
        {
          "type": "null"
        },
        {
          "type": "object",
          "required": [
            "sdkVersion"
          ],
          "propertyNames": {
            "type": "string",
            "maxLength": 64
          },
          "maxProperties": 64,
          "additionalProperties": {},
          "$comment": "Opaque reader result (at most 524288 bytes as canonical JSON). Keys are the reader's own."
        }
      ]
    }
  },
  "$defs": {
    "unit": {
      "type": "number",
      "minimum": 0,
      "maximum": 1
    },
    "region": {
      "$comment": "Normalized to the rendered page (0..1). box is [left, top, right, bottom] with left <= right and top <= bottom.",
      "type": "object",
      "additionalProperties": false,
      "required": [
        "box",
        "polygon"
      ],
      "properties": {
        "box": {
          "anyOf": [
            {
              "type": "null"
            },
            {
              "type": "array",
              "minItems": 4,
              "maxItems": 4,
              "items": {
                "$ref": "#/$defs/unit"
              }
            }
          ]
        },
        "polygon": {
          "type": "array",
          "maxItems": 8,
          "items": {
            "type": "array",
            "minItems": 2,
            "maxItems": 2,
            "items": {
              "$ref": "#/$defs/unit"
            }
          }
        }
      }
    },
    "word": {
      "type": "object",
      "additionalProperties": false,
      "required": [
        "text",
        "region",
        "confidence"
      ],
      "properties": {
        "text": {
          "type": "string",
          "minLength": 0,
          "maxLength": 2048
        },
        "region": {
          "$ref": "#/$defs/region"
        },
        "confidence": {
          "anyOf": [
            {
              "type": "null"
            },
            {
              "$ref": "#/$defs/unit"
            }
          ]
        }
      }
    },
    "line": {
      "type": "object",
      "additionalProperties": false,
      "required": [
        "text",
        "region",
        "confidence",
        "words"
      ],
      "properties": {
        "text": {
          "type": "string",
          "minLength": 0,
          "maxLength": 8192
        },
        "region": {
          "$ref": "#/$defs/region"
        },
        "confidence": {
          "anyOf": [
            {
              "type": "null"
            },
            {
              "$ref": "#/$defs/unit"
            }
          ]
        },
        "words": {
          "type": "array",
          "maxItems": 2048,
          "items": {
            "$ref": "#/$defs/word"
          }
        }
      }
    },
    "block": {
      "type": "object",
      "additionalProperties": false,
      "required": [
        "text",
        "region",
        "lines"
      ],
      "properties": {
        "text": {
          "type": "string",
          "minLength": 0,
          "maxLength": 65536
        },
        "region": {
          "$ref": "#/$defs/region"
        },
        "lines": {
          "type": "array",
          "maxItems": 10000,
          "items": {
            "$ref": "#/$defs/line"
          }
        }
      }
    },
    "page": {
      "type": "object",
      "additionalProperties": false,
      "required": [
        "index",
        "width",
        "height",
        "engine",
        "text",
        "blocks"
      ],
      "properties": {
        "index": {
          "type": "integer",
          "minimum": 0,
          "maximum": 199
        },
        "width": {
          "type": "integer",
          "minimum": 1,
          "maximum": 20000
        },
        "height": {
          "type": "integer",
          "minimum": 1,
          "maximum": 20000
        },
        "engine": {
          "type": "string",
          "minLength": 1,
          "maxLength": 128,
          "pattern": "^[\\x20-\\x7e]+$"
        },
        "text": {
          "type": "string",
          "minLength": 0,
          "maxLength": 262144
        },
        "blocks": {
          "type": "array",
          "maxItems": 2000,
          "items": {
            "$ref": "#/$defs/block"
          }
        }
      }
    }
  }
}