docs: update contract registration tutorial to include nft example (#62)

docs/explanations/nft.md

@@ -49,7 +49,7 @@ Structurally, there is no difference between an NFT contract and a non-NFT contr
 
 NFT contracts will often set document creation restrictions and enable document transfers. Default options for modifying, deleting, and transferring documents can be specified at the contract level and overridden as needed for specific document types.
 
-Once the data contract design is completed, the contract can be registered on the network in preparation for NFT document creation.
+Once the data contract design is completed, the contract can be registered on the network in preparation for NFT document creation. See the [contract registration tutorial](../tutorials/contracts-and-documents/register-a-data-contract.md) for example code.
 
 ### Minting NFTs
 

docs/tutorials/contracts-and-documents/register-a-data-contract.md

@@ -33,6 +33,8 @@ data.
 The fifth tab shows a data contract configured to store contract history. This allows all contract
 revisions to be retrieved in the future as needed.
 
+The sixth tab shows a data contract configured for creating NFTs. It allows documents to be deleted, transferred, or traded. It also limits document creation to the contract owner. See the [NFT explanation section](../../explanations/nft.md) for more details about NFTs on Dash Platform. **_Note: the JavaScript SDK supports NFT contract registration, but does not currently support trades or transfers._**
+
 > 🚧
 >
 > Since Platform v0.25.16, each document property must assign `position` value to support [backwards compatibility](https://github.com/dashpay/platform/pull/1594) for contract updates.
@@ -161,6 +163,82 @@ array of bytes (e.g. a NodeJS Buffer).
 }
 ```
 :::
+
+:::{tab-item} 6. NFT Contract
+:sync: nft
+```json
+// To use contract documents as NFTs, configure settings for modifying
+// deleting, transferring, trading, or restricting creation as needed
+{
+  "card": {
+    "type": "object",
+    "documentsMutable": false,    // true = documents can be modified (replaced)
+    "canBeDeleted": true,         // true = documents can be deleted
+    "transferable": 1,            // 0 = transfers disabled; 1 = transfers enabled
+    "tradeMode": 1,               // 0 = no trading; 1 = direct purchases
+    "creationRestrictionMode": 1, // 0 = anyone can mint; 1 = only contract owner can mint
+    "properties": {
+      "name": {
+        "type": "string",
+        "description": "Name of the card",
+        "minLength": 0,
+        "maxLength": 63,
+        "position": 0
+      },
+      "description": {
+        "type": "string",
+        "description": "Description of the card",
+        "minLength": 0,
+        "maxLength": 256,
+        "position": 1
+      },
+      "attack": {
+        "type": "integer",
+        "description": "Attack power of the card",
+        "position": 2
+      },
+      "defense": {
+        "type": "integer",
+        "description": "Defense level of the card",
+        "position": 3
+      }
+    },
+    "indices": [
+      {
+        "name": "owner",
+        "properties": [
+          {
+            "$ownerId": "asc"
+          }
+        ]
+      },
+      {
+        "name": "attack",
+        "properties": [
+          {
+            "attack": "asc"
+          }
+        ]
+      },
+      {
+        "name": "defense",
+        "properties": [
+          {
+            "defense": "asc"
+          }
+        ]
+      }
+    ],
+    "required": [
+      "name",
+      "attack",
+      "defense"
+    ],
+    "additionalProperties": false
+  }
+}
+```
+:::
 ::::
 
 > 📘
@@ -373,6 +451,101 @@ const registerContract = async () => {
   return contract;
 };
 
+registerContract()
+  .then((d) => console.log('Contract registered:\n', d.toJSON()))
+  .catch((e) => console.error('Something went wrong:\n', e))
+  .finally(() => client.disconnect());
+```
+:::
+
+:::{tab-item} 6. NFT Contract
+:sync: nft
+```javascript
+const setupDashClient = require('../setupDashClient');
+
+const client = setupDashClient();
+
+const registerContract = async () => {
+  const { platform } = client;
+  const identity = await platform.identities.get('an identity ID goes here');
+
+  const contractDocuments = {
+    card: {
+      type: "object",
+      documentsMutable: false,    // Documents cannot be modified/replaced
+      canBeDeleted: true,         // Documents can be deleted
+      transferable: 1,            // Transfers enabled
+      tradeMode: 1,               // Direct purchase trades enabled
+      creationRestrictionMode: 1, // Only the contract owner can mint      
+      properties: {
+        name: {
+          type: "string",
+          description: "Name of the card",
+          minLength: 0,
+          maxLength: 63,
+          position: 0
+        },
+        description: {
+          type: "string",
+          description: "Description of the card",
+          minLength: 0,
+          maxLength: 256,
+          position: 1
+        },
+        attack: {
+          type: "integer",
+          description: "Attack power of the card",
+          position: 2
+        },
+        defense: {
+          type: "integer",
+          description: "Defense level of the card",
+          position: 3
+        }
+      },
+      indices: [
+        {
+          name: "owner",
+          properties: [
+            {
+              $ownerId: "asc"
+            }
+          ]
+        },
+        {
+          name: "attack",
+          properties: [
+            {
+              attack: "asc"
+            }
+          ]
+        },
+        {
+          name: "defense",
+          properties: [
+            {
+              defense: "asc"
+            }
+          ]
+        }
+      ],
+      required: [
+        "name",
+        "attack",
+        "defense"
+      ],
+      additionalProperties: false
+    }
+  }
+
+  const contract = await platform.contracts.create(contractDocuments, identity);
+  console.dir({ contract: contract.toJSON() });
+
+  // Sign and submit the data contract
+  await platform.contracts.publish(contract, identity);
+  return contract;
+};
+
 registerContract()
   .then((d) => console.log('Contract registered:\n', d.toJSON()))
   .catch((e) => console.error('Something went wrong:\n', e))