<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
           targetNamespace="http://example.org/catalog"
           xmlns:cat="http://example.org/catalog"
           elementFormDefault="qualified">
  <xs:element name="catalog">
    <xs:complexType>
      <xs:sequence>
        <xs:element name="product" type="cat:ProductType" maxOccurs="unbounded"/>
      </xs:sequence>
      <xs:attribute name="version" type="xs:string" use="required"/>
    </xs:complexType>
  </xs:element>
  <xs:complexType name="ProductType">
    <xs:sequence>
      <xs:element name="name" type="xs:string"/>
      <xs:element name="description" type="xs:string" minOccurs="0"/>
      <xs:element name="price" type="cat:PriceType"/>
      <xs:element name="category" type="xs:string" maxOccurs="3"/>
      <xs:element name="stock" type="xs:positiveInteger"/>
      <xs:element name="featured" type="xs:boolean" default="false"/>
    </xs:sequence>
    <xs:attribute name="id" type="cat:SKUType" use="required"/>
    <xs:attribute name="available" type="xs:boolean" default="true"/>
  </xs:complexType>
  <xs:complexType name="PriceType">
    <xs:simpleContent>
      <xs:extension base="xs:decimal">
        <xs:attribute name="currency" type="cat:CurrencyCodeType" default="USD"/>
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType>
  <xs:simpleType name="SKUType">
    <xs:restriction base="xs:string">
      <xs:pattern value="[A-Z]{2}-\d{6}"/>
    </xs:restriction>
  </xs:simpleType>
  <xs:simpleType name="CurrencyCodeType">
    <xs:restriction base="xs:string">
      <xs:enumeration value="USD"/>
      <xs:enumeration value="EUR"/>
      <xs:enumeration value="GBP"/>
      <xs:enumeration value="JPY"/>
    </xs:restriction>
  </xs:simpleType>
</xs:schema>

{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "title": "Product Catalog",
  "description": "Schema for product catalog data",
  "$id": "http://example.org/catalog",
  
  "definitions": {
    "SKUType": {
      "type": "string",
      "pattern": "[A-Z]{2}-\\d{6}"
    },
    "CurrencyCodeType": {
      "type": "string",
      "enum": ["USD", "EUR", "GBP", "JPY"]
    },
    "PriceType": {
      "type": "object",
      "properties": {
        "value": { "type": "number" },
        "currency": { 
          "$ref": "#/definitions/CurrencyCodeType",
          "default": "USD"
        }
      },
      "required": ["value"]
    },
    "ProductType": {
      "type": "object",
      "properties": {
        "id": { "$ref": "#/definitions/SKUType" },
        "available": { 
          "type": "boolean",
          "default": true
        },
        "name": { "type": "string" },
        "description": { "type": "string" },
        "price": { "$ref": "#/definitions/PriceType" },
        "category": {
          "type": "array",
          "items": { "type": "string" },
          "minItems": 1,
          "maxItems": 3
        },
        "stock": { 
          "type": "integer",
          "minimum": 1
        },
        "featured": { 
          "type": "boolean",
          "default": false
        }
      },
      "required": ["id", "name", "price", "stock", "category"],
      "additionalProperties": false
    }
  },
  
  "type": "object",
  "properties": {
    "catalog": {
      "type": "object",
      "properties": {
        "version": { "type": "string" },
        "product": {
          "type": "array",
          "items": { "$ref": "#/definitions/ProductType" },
          "minItems": 1
        }
      },
      "required": ["version", "product"],
      "additionalProperties": false
    }
  },
  "required": ["catalog"]
}

const Ajv = require('ajv');
const ajv = new Ajv({allErrors: true});
const validate = ajv.compile(jsonSchema);
const valid = validate(jsonData);
if (!valid) console.log(validate.errors);

{
  "catalog": {
    "version": "1.0",
    "product": [
      {
        "id": "AB-123456",
        "name": "Smartphone",
        "price": {
          "value": 499.99,
          "currency": "USD"
        },
        "category": ["Electronics", "Gadgets"],
        "stock": 50,
        "featured": true
      },
      {
        "id": "CD-654321",
        "name": "Laptop",
        "description": "Powerful laptop for professionals",
        "price": {
          "value": 1299.99, "currency": "EUR" 
      }, 
        "category": ["Electronics", "Computers"], 
        "stock": 25 
      } 
    ] 
  } 
}

Verify that this data validates against our JSON Schema to ensure the conversion is working correctly.
## Advanced Conversion Scenarios
Beyond basic conversion, several complex scenarios require special handling.
### Handling Recursive Structures
XSD supports recursive structures through element references. In JSON Schema, we use `$ref` references to achieve the same effect:
**XSD with recursion:**
```xml
<xs:element name="category">
  <xs:complexType>
    <xs:sequence>
      <xs:element name="name" type="xs:string"/>
      <xs:element ref="category" minOccurs="0" maxOccurs="unbounded"/>
    </xs:sequence>
  </xs:complexType>
</xs:element>

{
  "definitions": {
    "category": {
      "type": "object",
      "properties": {
        "name": { "type": "string" },
        "category": {
          "type": "array",
          "items": { "$ref": "#/definitions/category" }
        }
      },
      "required": ["name"]
    }
  },
  "type": "object",
  "properties": {
    "category": { "$ref": "#/definitions/category" }
  }
}

<xs:element name="paragraph">
  <xs:complexType mixed="true">
    <xs:sequence>
      <xs:element name="emphasis" type="xs:string" minOccurs="0" maxOccurs="unbounded"/>
      <xs:element name="link" type="LinkType" minOccurs="0" maxOccurs="unbounded"/>
    </xs:sequence>
  </xs:complexType>
</xs:element>