feat(examples): define metadata & royalty info for GRC721 realm

examples/gno.land/p/demo/grc/grc721/errors.gno

@@ -14,4 +14,9 @@ var (
 	ErrTransferToNonGRC721Receiver = errors.New("transfer to non GRC721Receiver implementer")
 	ErrCallerIsNotOwnerOrApproved  = errors.New("caller is not token owner or approved")
 	ErrTokenIdAlreadyExists        = errors.New("token id already exists")
+
+	// ERC721Royalty
+	ErrInvalidRoyaltyPercentage = errors.New("invalid royalty percentage")
+	ErrInvalidRoyaltyPaymentAddress = errors.New("invalid royalty paymentAddress")
+	ErrCannotCalculateRoyaltyAmount = errors.New("cannot calculate royalty amount")
 )

examples/gno.land/p/demo/grc/grc721/igrc721_metadata.gno

@@ -0,0 +1,27 @@
+
+package grc721
+
+type IGRC721Metadata interface {	
+	IGRC721
+
+	SetExtension(tid TokenID, extension Metadata) error
+	Extension(tid TokenID) (Metadata, error)
+}
+
+type Trait struct{
+    DisplayType string
+    TraitType string
+    Value string
+}
+
+type Metadata struct {
+	Image string
+	ImageData string
+	ExternalURL string
+	Description string
+	Name string
+	Attributes []Trait
+	BackgroundColor string
+	AnimationURL string
+	YoutubeURL string
+}

examples/gno.land/p/demo/grc/grc721/igrc721_royalty.gno

@@ -0,0 +1,14 @@
+package grc721
+
+import (
+	"std"
+)
+
+type IGRC721Royalty interface {	
+	RoyaltyInfo(tokenID TokenID, salePrice uint64) (std.Address, uint64, error)
+}
+
+type RoyaltyInfo struct {
+	PaymentAddress std.Address
+	Percentage uint64
+}

examples/gno.land/p/demo/grc/grc721/nft_metadata.gno

@@ -0,0 +1,85 @@
+package grc721
+
+import (
+	"std"
+
+	"gno.land/p/demo/avl"
+)
+
+// metadataNFT represents an NFT with metadata extensions.
+type metadataNFT struct {
+	*basicNFT
+
+	extensions avl.Tree
+}
+
+// Ensure that metadataNFT implements the IGRC721Metadata interface.
+var _ IGRC721Metadata = (*metadataNFT)(nil)
+
+// NewNFTWithMetadata creates a new basic NFT with metadata extensions.
+func NewNFTWithMetadata(name string, symbol string) *metadataNFT {
+
+	nft := NewBasicNFT(name, symbol)
+
+	return &metadataNFT{
+		basicNFT:   nft,
+		extensions: avl.Tree{},
+	}
+}
+
+// SetExtension sets the metadata extension for the given token ID.
+func (s *metadataNFT) SetExtension(tid TokenID, extension Metadata) (bool, error) {
+	// Check for the right owner
+	owner, err := s.basicNFT.OwnerOf(tid)
+	if err != nil {
+		return false, err
+	}
+	caller := std.PrevRealm().Addr()
+	if caller != owner {
+		return false, ErrCallerIsNotOwner
+	}
+	s.extensions.Set(string(tid), extension)
+	return true, nil
+}
+
+// Extension retrieves the metadata extension for the given token ID.
+func (s *metadataNFT) Extension(tid TokenID) (Metadata, error) {
+	extension, found := s.extensions.Get(string(tid))
+	if !found {
+		return Metadata{}, ErrInvalidTokenId
+	}
+
+	return extension.(Metadata), nil
+}
+
+func (s *metadataNFT) mint(to std.Address, tid TokenID) error {
+	if err := isValidAddress(to); err != nil {
+		return err
+	}
+
+	if s.basicNFT.exists(tid) {
+		return ErrTokenIdAlreadyExists
+	}
+
+	s.basicNFT.beforeTokenTransfer(zeroAddress, to, tid, 1)
+
+	// Check that tokenId was not minted by `beforeTokenTransfer`
+	if s.basicNFT.exists(tid) {
+		return ErrTokenIdAlreadyExists
+	}
+
+	toBalance, err := s.basicNFT.BalanceOf(to)
+	if err != nil {
+		return err
+	}
+	toBalance += 1
+	s.basicNFT.balances.Set(to.String(), toBalance)
+	s.basicNFT.owners.Set(string(tid), to)
+
+	event := TransferEvent{zeroAddress, to, tid}
+	emit(&event)
+
+	s.basicNFT.afterTokenTransfer(zeroAddress, to, tid, 1)
+
+	return nil
+}

examples/gno.land/p/demo/grc/grc721/nft_metadata_test.gno

@@ -0,0 +1,130 @@
+package grc721
+
+import (
+	"std"
+	"testing"
+
+	"gno.land/p/demo/testutils"
+	"gno.land/p/demo/users"
+)
+
+func TestSetExtension(t *testing.T) {
+	dummy := NewNFTWithMetadata(dummyNFTName, dummyNFTSymbol)
+	if dummy == nil {
+		t.Errorf("should not be nil")
+	}
+
+	addr1 := std.Address("g1var589z07ppjsjd24ukm4uguzwdt0tw7g47cgm")
+	addr2 := std.Address("g1us8428u2a5satrlxzagqqa5m6vmuze025anjlj")
+
+	name := "test"
+	description := "test"
+	image := "test"
+	imageData := "test"
+	externalURL := "test"
+	attributes := []Trait{}
+	backgroundColor := "test"
+	animationURL := "test"
+	youtubeURL := "test"
+
+	std.TestSetOrigCaller(std.Address(addr1)) // addr1
+
+	dummy.mint(addr1, TokenID("1"))
+
+	_, derr := dummy.SetExtension(TokenID("1"), Metadata{
+		Name : name,
+		Description: description,
+		Image: image,
+		ImageData: imageData,
+		ExternalURL: externalURL,
+		Attributes: attributes,
+		BackgroundColor: backgroundColor,
+		AnimationURL: animationURL,
+		YoutubeURL: youtubeURL,
+	})
+
+	if derr != nil {
+		t.Errorf("Should not result in error ", derr.Error())
+	}
+
+	// Test case: Invalid token ID
+	_, err := dummy.SetExtension(TokenID("3"), Metadata{
+		Name : name,
+		Description: description,
+		Image: image,
+		ImageData: imageData,
+		ExternalURL: externalURL,
+		Attributes: attributes,
+		BackgroundColor: backgroundColor,
+		AnimationURL: animationURL,
+		YoutubeURL: youtubeURL,
+	})
+	if err != ErrInvalidTokenId {
+		t.Errorf("Expected error %v, got %v", ErrInvalidTokenId, err)
+	}
+
+	std.TestSetOrigCaller(std.Address(addr2)) // addr2
+
+	_, cerr := dummy.SetExtension(TokenID("1"), Metadata{
+		Name : name,
+		Description: description,
+		Image: image,
+		ImageData: imageData,
+		ExternalURL: externalURL,
+		Attributes: attributes,
+		BackgroundColor: backgroundColor,
+		AnimationURL: animationURL,
+		YoutubeURL: youtubeURL,
+	}) // addr2 trying to set Extension for token 1
+	if cerr != ErrCallerIsNotOwner {
+		t.Errorf("Expected error %v, got %v", ErrCallerIsNotOwner, cerr)
+	}
+
+	// Test case: Retrieving Extension
+	std.TestSetOrigCaller(std.Address(addr1)) // addr1
+
+	dummyExtension, err := dummy.Extension(TokenID("1"))
+	if err != nil {
+		t.Errorf("Extension error: %v", err.Error())
+
+	} else {
+		if dummyExtension.Image != image {
+			t.Errorf("Expected Extension's image %s, got %s", image, dummyExtension.Image)
+		}
+
+		if dummyExtension.ImageData != imageData {
+			t.Errorf("Expected Extension's imageData %s, got %s", imageData, dummyExtension.ImageData)
+		}
+
+		if dummyExtension.ExternalURL != externalURL {
+			t.Errorf("Expected Extension's externalURL %s, got %s", externalURL, dummyExtension.ExternalURL)
+		}
+
+		if dummyExtension.Description != description {
+			t.Errorf("Expected Extension's description %s, got %s", description, dummyExtension.Description)
+		}
+
+		if dummyExtension.Name != name {
+			t.Errorf("Expected Extension's name %s, got %s", name, dummyExtension.Name)
+		}
+
+		if len(dummyExtension.Attributes) != len(attributes) {
+			t.Errorf("Expected %d Extension's attributes, got %d", len(attributes), len(dummyExtension.Attributes))
+		}
+
+		if dummyExtension.BackgroundColor != backgroundColor {
+			t.Errorf("Expected Extension's backgroundColor %s, got %s", backgroundColor, dummyExtension.BackgroundColor)
+		}
+
+		if dummyExtension.AnimationURL != animationURL {
+			t.Errorf("Expected Extension's animationURL %s, got %s", animationURL, dummyExtension.AnimationURL)
+		}
+
+		if dummyExtension.YoutubeURL != youtubeURL {
+			t.Errorf("Expected Extension's youtubeURL %s, got %s", youtubeURL, dummyExtension.YoutubeURL)
+		}
+	}
+
+
+}
+

examples/gno.land/p/demo/grc/grc721/nft_royalty.gno

@@ -0,0 +1,76 @@
+package grc721
+
+import (
+	"std"
+
+	"gno.land/p/demo/avl"
+)
+
+// royaltyNFT represents a non-fungible token (NFT) with royalty functionality.
+type royaltyNFT struct {
+	*metadataNFT          // Embedding metadataNFT for NFT functionality
+	tokenRoyaltyInfo avl.Tree  // AVL tree to store royalty information for each token
+}
+
+
+// NewNFTWithRoyalty creates a new royalty NFT with the specified name, symbol, and royalty calculator.
+func NewNFTWithRoyalty(name string, symbol string) *royaltyNFT {
+	// Create a new NFT with metadata
+	nft := NewNFTWithMetadata(name, symbol)
+
+	return &royaltyNFT{
+		metadataNFT:        nft,
+		tokenRoyaltyInfo:   avl.Tree{},
+	}
+}
+
+// SetTokenRoyalty sets the royalty information for a specific token ID.
+func (r *royaltyNFT) SetTokenRoyalty(tid TokenID, royaltyInfo RoyaltyInfo) (bool, error) {
+	// Validate the payment address
+	if err := isValidAddress(royaltyInfo.PaymentAddress); err != nil {
+		return false, ErrInvalidRoyaltyPaymentAddress
+	}
+
+	// Check if royalty percentage exceeds 100%
+	if royaltyInfo.Percentage > 100 {
+		return false, ErrInvalidRoyaltyPercentage
+	}
+
+	// Check if the caller is the owner of the token
+	owner, err := r.metadataNFT.OwnerOf(tid)
+	if err != nil {
+		return false, err
+	}
+	caller := std.PrevRealm().Addr()
+	if caller != owner {
+		return false, ErrCallerIsNotOwner
+	}
+
+	// Set royalty information for the token
+	r.tokenRoyaltyInfo.Set(string(tid), royaltyInfo)
+	return true, nil
+}
+
+// RoyaltyInfo returns the royalty information for the given token ID and sale price.
+func (r *royaltyNFT) RoyaltyInfo(tid TokenID, salePrice uint64) (std.Address, uint64, error) {
+	// Retrieve royalty information for the token
+	val, found := r.tokenRoyaltyInfo.Get(string(tid))
+	if !found {
+		return "", 0, ErrInvalidTokenId
+	}
+
+	royaltyInfo := val.(RoyaltyInfo)
+
+	// Calculate royalty amount using the provided calculator
+	royaltyAmount, err := r.calculateRoyaltyAmount(salePrice, royaltyInfo.Percentage)
+	if err != nil {
+		return "", 0, ErrCannotCalculateRoyaltyAmount
+	}
+
+	return royaltyInfo.PaymentAddress, royaltyAmount, nil
+}
+
+func (r *royaltyNFT) calculateRoyaltyAmount(salePrice, percentage uint64) (uint64, error) {
+	royaltyAmount := (salePrice * percentage) / 100
+	return royaltyAmount, nil
+}