{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "$id": "https://raw.githubusercontent.com/opendataloader-project/opendataloader-pdf/main/schema.json",
  "title": "OpenDataLoader PDF Output",
  "description": "JSON output schema for OpenDataLoader PDF conversion",
  "type": "object",
  "required": ["file name", "number of pages", "author", "title", "creation date", "modification date", "kids"],
  "properties": {
    "file name": {
      "type": "string",
      "description": "Name of the processed PDF"
    },
    "number of pages": {
      "type": "integer",
      "description": "Total page count"
    },
    "author": {
      "type": ["string", "null"],
      "description": "PDF author metadata"
    },
    "title": {
      "type": ["string", "null"],
      "description": "PDF title metadata"
    },
    "creation date": {
      "type": ["string", "null"],
      "description": "PDF creation timestamp"
    },
    "modification date": {
      "type": ["string", "null"],
      "description": "PDF modification timestamp"
    },
    "kids": {
      "type": "array",
      "description": "Top-level content elements (per page)",
      "items": {
        "$ref": "#/$defs/contentElement"
      }
    }
  },
  "$defs": {
    "boundingBox": {
      "type": "array",
      "description": "Bounding box coordinates [left, bottom, right, top]",
      "items": {
        "type": "number"
      },
      "minItems": 4,
      "maxItems": 4
    },
    "baseElement": {
      "type": "object",
      "properties": {
        "type": {
          "type": "string",
          "description": "Element type"
        },
        "id": {
          "type": "integer",
          "description": "Unique content identifier"
        },
        "level": {
          "type": "string",
          "description": "Heading or structural level"
        },
        "page number": {
          "type": "integer",
          "description": "Page containing the element (1-indexed)"
        },
        "bounding box": {
          "$ref": "#/$defs/boundingBox"
        }
      },
      "required": ["type", "page number", "bounding box"]
    },
    "textProperties": {
      "type": "object",
      "properties": {
        "font": {
          "type": "string",
          "description": "Font name"
        },
        "font size": {
          "type": "number",
          "description": "Font size"
        },
        "text color": {
          "type": "string",
          "description": "RGB color as string array"
        },
        "content": {
          "type": "string",
          "description": "Raw text value"
        },
        "hidden text": {
          "type": "boolean",
          "description": "Whether this is hidden text (e.g., OCR layer)"
        }
      },
      "required": ["font", "font size", "text color", "content"]
    },
    "contentElement": {
      "oneOf": [
        { "$ref": "#/$defs/paragraph" },
        { "$ref": "#/$defs/heading" },
        { "$ref": "#/$defs/caption" },
        { "$ref": "#/$defs/table" },
        { "$ref": "#/$defs/textBlock" },
        { "$ref": "#/$defs/list" },
        { "$ref": "#/$defs/image" },
        { "$ref": "#/$defs/headerFooter" }
      ]
    },
    "paragraph": {
      "allOf": [
        { "$ref": "#/$defs/baseElement" },
        { "$ref": "#/$defs/textProperties" },
        {
          "type": "object",
          "properties": {
            "type": { "const": "paragraph" }
          }
        }
      ]
    },
    "heading": {
      "allOf": [
        { "$ref": "#/$defs/baseElement" },
        { "$ref": "#/$defs/textProperties" },
        {
          "type": "object",
          "properties": {
            "type": { "const": "heading" },
            "heading level": {
              "type": "integer",
              "minimum": 1,
              "description": "Heading level (e.g., 1 for h1)"
            }
          },
          "required": ["heading level"]
        }
      ]
    },
    "caption": {
      "allOf": [
        { "$ref": "#/$defs/baseElement" },
        { "$ref": "#/$defs/textProperties" },
        {
          "type": "object",
          "properties": {
            "type": { "const": "caption" },
            "linked content id": {
              "type": "integer",
              "description": "ID of the linked content element (table, image, etc.)"
            }
          }
        }
      ]
    },
    "table": {
      "allOf": [
        { "$ref": "#/$defs/baseElement" },
        {
          "type": "object",
          "properties": {
            "type": { "const": "table" },
            "number of rows": {
              "type": "integer",
              "description": "Row count"
            },
            "number of columns": {
              "type": "integer",
              "description": "Column count"
            },
            "previous table id": {
              "type": "integer",
              "description": "Linked table identifier (if broken across pages)"
            },
            "next table id": {
              "type": "integer",
              "description": "Linked table identifier"
            },
            "rows": {
              "type": "array",
              "description": "Row objects",
              "items": { "$ref": "#/$defs/tableRow" }
            }
          },
          "required": ["number of rows", "number of columns", "rows"]
        }
      ]
    },
    "tableRow": {
      "type": "object",
      "properties": {
        "type": { "const": "table row" },
        "row number": {
          "type": "integer",
          "description": "Row index (1-indexed)"
        },
        "cells": {
          "type": "array",
          "description": "Cell objects",
          "items": { "$ref": "#/$defs/tableCell" }
        }
      },
      "required": ["type", "row number", "cells"]
    },
    "tableCell": {
      "allOf": [
        { "$ref": "#/$defs/baseElement" },
        {
          "type": "object",
          "properties": {
            "type": { "const": "table cell" },
            "row number": {
              "type": "integer",
              "description": "Row index of the cell (1-indexed)"
            },
            "column number": {
              "type": "integer",
              "description": "Column index of the cell (1-indexed)"
            },
            "row span": {
              "type": "integer",
              "minimum": 1,
              "description": "Number of rows spanned"
            },
            "column span": {
              "type": "integer",
              "minimum": 1,
              "description": "Number of columns spanned"
            },
            "kids": {
              "type": "array",
              "description": "Nested content elements",
              "items": { "$ref": "#/$defs/contentElement" }
            }
          },
          "required": ["row number", "column number", "row span", "column span", "kids"]
        }
      ]
    },
    "textBlock": {
      "allOf": [
        { "$ref": "#/$defs/baseElement" },
        {
          "type": "object",
          "properties": {
            "type": { "const": "text block" },
            "kids": {
              "type": "array",
              "description": "Text block children",
              "items": { "$ref": "#/$defs/contentElement" }
            }
          },
          "required": ["kids"]
        }
      ]
    },
    "list": {
      "allOf": [
        { "$ref": "#/$defs/baseElement" },
        {
          "type": "object",
          "properties": {
            "type": { "const": "list" },
            "numbering style": {
              "type": "string",
              "description": "Marker style (ordered, bullet, etc.)"
            },
            "number of list items": {
              "type": "integer",
              "description": "Item count"
            },
            "previous list id": {
              "type": "integer",
              "description": "Linked list identifier"
            },
            "next list id": {
              "type": "integer",
              "description": "Linked list identifier"
            },
            "list items": {
              "type": "array",
              "description": "Item nodes",
              "items": { "$ref": "#/$defs/listItem" }
            }
          },
          "required": ["numbering style", "number of list items", "list items"]
        }
      ]
    },
    "listItem": {
      "allOf": [
        { "$ref": "#/$defs/baseElement" },
        { "$ref": "#/$defs/textProperties" },
        {
          "type": "object",
          "properties": {
            "type": { "const": "list item" },
            "kids": {
              "type": "array",
              "description": "Nested content elements",
              "items": { "$ref": "#/$defs/contentElement" }
            }
          },
          "required": ["kids"]
        }
      ]
    },
    "image": {
      "allOf": [
        { "$ref": "#/$defs/baseElement" },
        {
          "type": "object",
          "properties": {
            "type": { "const": "image" },
            "source": {
              "type": "string",
              "description": "Relative path to the image file"
            },
            "data": {
              "type": "string",
              "description": "Base64 data URI (when embed-images is enabled)"
            },
            "format": {
              "type": "string",
              "description": "Image format (png, jpeg)",
              "enum": ["png", "jpeg"]
            }
          }
        }
      ]
    },
    "headerFooter": {
      "allOf": [
        { "$ref": "#/$defs/baseElement" },
        {
          "type": "object",
          "properties": {
            "type": {
              "type": "string",
              "enum": ["header", "footer"]
            },
            "kids": {
              "type": "array",
              "description": "Content elements within the header or footer",
              "items": { "$ref": "#/$defs/contentElement" }
            }
          },
          "required": ["kids"]
        }
      ]
    }
  }
}