1const (
2	MintEvent           = "Mint"
3	BurnEvent           = "Burn"
4	TransferEvent       = "Transfer"
5	ApprovalEvent       = "Approval"
6	ApprovalForAllEvent = "ApprovalForAll"
7	TokenURIUpdateEvent = "TokenUriUpdate"
8	MetadataUpdateEvent = "MetadataUpdate"
9)

1const (
2	MaxNameLen   = 64
3	MaxSymbolLen = 11
4)

 1var (
 2	ErrInvalidTokenId              = errors.New("invalid token id")
 3	ErrInvalidAddress              = errors.New("invalid address")
 4	ErrTokenIdNotHasApproved       = errors.New("token id not approved for anyone")
 5	ErrApprovalToCurrentOwner      = errors.New("approval to current owner")
 6	ErrCallerIsNotOwner            = errors.New("caller is not token owner")
 7	ErrCallerNotApprovedForAll     = errors.New("caller is not approved for all")
 8	ErrCannotTransferToSelf        = errors.New("cannot send transfer to self")
 9	ErrTransferFromIncorrectOwner  = errors.New("transfer from incorrect owner")
10	ErrTransferToNonGRC721Receiver = errors.New("transfer to non GRC721Receiver implementer")
11	ErrCallerIsNotOwnerOrApproved  = errors.New("caller is not token owner or approved")
12	ErrTokenIdAlreadyExists        = errors.New("token id already exists")
13
14	// NewBasicNFT realm binding
15	ErrSpoofedRealm  = errors.New("rlm does not match the current crossing frame")
16	ErrNotRealm      = errors.New("rlm must be a realm (got EOA/origin)")
17	ErrInvalidName   = errors.New("invalid token name (empty, too long, or contains control chars)")
18	ErrInvalidSymbol = errors.New("invalid token symbol (empty, too long, or contains chars outside [A-Za-z0-9_-])")
19
20	// ERC721Royalty
21	ErrInvalidRoyaltyPercentage     = errors.New("invalid royalty percentage")
22	ErrInvalidRoyaltyPaymentAddress = errors.New("invalid royalty paymentAddress")
23	ErrCannotCalculateRoyaltyAmount = errors.New("cannot calculate royalty amount")
24)

1func NewBasicNFT(_ int, rlm realm, name, symbol string) *BasicNFT

1func NewNFTWithMetadata(_ int, rlm realm, name, symbol string) *metadataNFT

1func NewNFTWithRoyalty(_ int, rlm realm, name, symbol string) *royaltyNFT

 1type BasicNFT struct {
 2	name              string
 3	symbol            string
 4	origRealm         string   // owning realm's package path
 5	owners            avl.Tree // tokenId -> OwnerAddress
 6	balances          avl.Tree // OwnerAddress -> TokenCount
 7	tokenApprovals    avl.Tree // TokenId -> ApprovedAddress
 8	tokenURIs         avl.Tree // TokenId -> URIs
 9	operatorApprovals avl.Tree // "OwnerAddress:OperatorAddress" -> bool
10}

1type IGRC2981 interface {
2	// RoyaltyInfo retrieves royalty information for a tokenID and salePrice.
3	// It returns the payment address, royalty amount, and an error if any.
4	RoyaltyInfo(tokenID TokenID, salePrice int64) (address, int64, error)
5}

1type IGRC721CollectionMetadata interface {
2	Name() string   // Name returns the name of the collection.
3	Symbol() string // Symbol returns the symbol of the collection.
4}

1type IGRC721Metadata interface {
2	IGRC721CollectionMetadata
3	TokenURI(tid TokenID) (string, error) // TokenURI returns the URI of a specific token.
4}

1type IGRC721MetadataOnchain interface {
2	IGRC721CollectionMetadata
3	TokenMetadata(tid TokenID) (Metadata, error)
4}

1type IGRC721Reader interface {
2	Name() string
3	Symbol() string
4	TokenCount() int64
5	BalanceOf(owner address) (int64, error)
6	OwnerOf(tid TokenID) (address, error)
7	GetApproved(tid TokenID) (address, error)
8	IsApprovedForAll(owner, operator address) bool
9}

 1type Metadata struct {
 2	Image           string  // URL to the image of the item. Can be any type of image (including SVGs, which will be cached into PNGs by OpenSea), IPFS or Arweave URLs or paths. We recommend using a minimum 3000 x 3000 image.
 3	ImageData       string  // Raw SVG image data, if you want to generate images on the fly (not recommended). Only use this if you're not including the image parameter.
 4	ExternalURL     string  // URL that will appear below the asset's image on OpenSea and will allow users to leave OpenSea and view the item on your site.
 5	Description     string  // Human-readable description of the item. Markdown is supported.
 6	Name            string  // Name of the item.
 7	Attributes      []Trait // Attributes for the item, which will show up on the OpenSea page for the item.
 8	BackgroundColor string  // Background color of the item on OpenSea. Must be a six-character hexadecimal without a pre-pended #
 9	AnimationURL    string  // URL to a multimedia attachment for the item. Supported file extensions: GLTF, GLB, WEBM, MP4, M4V, OGV, OGG, MP3, WAV, OGA, HTML (for rich experiences and interactive NFTs using JavaScript canvas, WebGL, etc.). Scripts and relative paths within the HTML page are now supported. Access to browser extensions is not supported.
10	YoutubeURL      string  // URL to a YouTube video (only used if animation_url is not provided).
11}

1type NFTGetter func() IGRC721Reader

1type RoyaltyInfo struct {
2	PaymentAddress address // PaymentAddress is the address where royalty payment should be sent.
3	Percentage     int64   // Percentage is the royalty percentage. It indicates the percentage of royalty to be paid for each sale. For example : Percentage = 10 => 10%
4}

1type TokenID string

1type TokenURI string

1type Trait struct {
2	DisplayType string
3	TraitType   string
4	Value       string
5}