# NRC721 Contract

package io.nuls.token.interfaces;

import io.nuls.contract.sdk.Address;
import io.nuls.contract.sdk.Event;
import io.nuls.contract.sdk.annotation.View;

import java.math.BigInteger;


public interface INRC721 {
    /**
     * Count all NFTs assigned to an owner
     * @param owner An address for whom to query the balance
     * @return The number of NFTs owned by `owner`, possibly zero
     */
    @View
    int balanceOf(Address owner);

    /**
     * Find the owner of an NFT
     * @param tokenId The identifier for an NFT
     * @return The address of the owner of the NFT
     */
    @View
    Address ownerOf(BigInteger tokenId);

    /**
     * Transfers the ownership of an NFT from one address to another address.
     * When transfer is complete, this function checks if `to` is a smart contract.
     * If so, it calls `onNRC721Received` on `to` and throws if the return value is `false`.
     * @throws revert unless `Msg.sender()` is the current owner, an authorized
     *          operator, or the approved address for this NFT.
     * @throws revert if `from` is not the current owner.
     * @throws revert if `tokenId` is not a valid NFT.
     * @param from The current owner of the NFT
     * @param to The new owner
     * @param tokenId The NFT to transfer
     * @param data Additional data with no specified format, sent in call to `to`
     */
    void safeTransferFrom(Address from, Address to, BigInteger tokenId, String data);

    /**
     * Transfers the ownership of an NFT from one address to another address.
     * This works identically to the other function with an extra data parameter,
     *  except this function just sets data to "".
     * @param from The current owner of the NFT
     * @param to The new owner
     * @param tokenId The NFT to transfer
     */
    void safeTransferFrom(Address from, Address to, BigInteger tokenId);

    /**
     * Transfer ownership of an NFT -- THE CALLER IS RESPONSIBLE
     *  TO CONFIRM THAT `to` IS CAPABLE OF RECEIVING NFTS OR ELSE
     *  THEY MAY BE PERMANENTLY LOST
     * @throws Revert unless `Msg.sender()` is the current owner, an authorized
     *  operator, or the approved address for this NFT.
     * @throws Revert if `from` is not the current owner.
     * @throws Revert if `tokenId` is not a valid NFT.
     * @param from The current owner of the NFT
     * @param to The new owner
     * @param tokenId The NFT to transfer
     */
    void transferFrom(Address from, Address to, BigInteger tokenId);

    /**
     * Change or reaffirm the approved address for an NFT
     * @throws revert unless `Msg.sender()` is the current NFT owner, or an authorized
     *  operator of the current owner.
     * @param approved The new approved NFT controller
     * @param tokenId The NFT to approve
     */
    void approve(Address to, BigInteger tokenId);

    /**
     * Enable or disable approval for a third party ("operator") to manage
     *  all of `Msg.sender()`'s assets.
     * Emits the ApprovalForAll event. The contract MUST allow multiple operators per owner.
     * @param operator Address to add to the set of authorized operators
     * @param approved True if the operator is approved, false to revoke approval
     */
    void setApprovalForAll(Address operator, boolean approved);

    /**
     * Get the approved address for a single NFT.
     * @throws revert if there is none or if `tokenId` is not a valid NFT.
     * @param tokenId The NFT to find the approved address for
     * @return The approved address for this NFT.
     */
    @View
    Address getApproved(BigInteger tokenId);

    /**
     * Query if an address is an authorized operator for another address
     * @param owner The address that owns the NFTs
     * @param operator The address that acts on behalf of the owner
     * @return True if `operator` is an approved operator for `owner`, false otherwise
     */
    @View
    boolean isApprovedForAll(Address owner, Address operator);

    /**
     * This emits when ownership of any NFT changes by any mechanism.
     *  This event emits when NFTs are created (`from` is NULL) and destroyed.
     *  At the time of any transfer, the approved address for that NFT (if any) is reset to none.
     *  <p>Exception: during contract creation, any number of NFTs may be created and assigned without emitting Transfer.</p>
     */
    class Transfer implements Event {
        private Address from;
        private Address to;
        private BigInteger tokenId;

        public Transfer(Address from, Address to, BigInteger tokenId) {
            this.from = from;
            this.to = to;
            this.tokenId = tokenId;
        }

        public Address getFrom() {
            return from;
        }

        public void setFrom(Address from) {
            this.from = from;
        }

        public Address getTo() {
            return to;
        }

        public void setTo(Address to) {
            this.to = to;
        }

        public BigInteger getTokenId() {
            return tokenId;
        }

        public void setTokenId(BigInteger tokenId) {
            this.tokenId = tokenId;
        }
    }

    /**
     * This emits when the approved address for an NFT is changed or reaffirmed.
     *  When a Transfer event emits, this also indicates that the approved address for that NFT (if any) is reset to none.
     */
    class Approval implements Event {
        private Address owner;
        private Address approved;
        private BigInteger tokenId;

        public Approval(Address owner, Address approved, BigInteger tokenId) {
            this.owner = owner;
            this.approved = approved;
            this.tokenId = tokenId;
        }

        public Address getOwner() {
            return owner;
        }

        public void setOwner(Address owner) {
            this.owner = owner;
        }

        public Address getApproved() {
            return approved;
        }

        public void setApproved(Address approved) {
            this.approved = approved;
        }

        public BigInteger getTokenId() {
            return tokenId;
        }

        public void setTokenId(BigInteger tokenId) {
            this.tokenId = tokenId;
        }
    }

    /**
     * This emits when an operator is enabled or disabled for an owner.
     * The operator can manage all NFTs of the owner.
     */
    class ApprovalForAll implements Event {
        private Address owner;
        private Address operator;
        private Boolean approved;

        public ApprovalForAll(Address owner, Address operator, Boolean approved) {
            this.owner = owner;
            this.operator = operator;
            this.approved = approved;
        }

        public Address getOwner() {
            return owner;
        }

        public void setOwner(Address owner) {
            this.owner = owner;
        }

        public Address getOperator() {
            return operator;
        }

        public void setOperator(Address operator) {
            this.operator = operator;
        }

        public Boolean getApproved() {
            return approved;
        }

        public void setApproved(Boolean approved) {
            this.approved = approved;
        }
    }
}

package io.nuls.token.interfaces;


public interface INRC165 {
    /**
     * Query if a contract implements an interface
     * @param interfaceName The interface name, as specified in the implementation class of NRC-165.
     *                      eg. interfaceName: ['INRC165', 'INRC721', 'INRC721Enumerable', 'INRC721Metadata']
     * @return `true` if the contract implements `interfaceName`, `false` otherwise
     */
    @View
    boolean supportsInterface(String interfaceName);
}

package io.nuls.token.interfaces;

import io.nuls.contract.sdk.Address;

import java.math.BigInteger;


public interface INRC721TokenReceiver {

    /**
     * Handle the receipt of an NFT.
     * The NRC721 smart contract calls this function on the recipient
     *  after a `transfer`. This function MAY revert and reject the
     *  transfer.
     *  Note: the contract address is always the message sender.
     * @param operator The address which called `safeTransferFrom` function
     * @param from The address which previously owned the token
     * @param tokenId The NFT identifier which is being transferred
     * @param data Additional data with no specified format
     * @return `true` if it accepts NFTs from other contracts, otherwise `false`
     */
    boolean onNRC721Received(Address operator, Address from, BigInteger tokenId, String data);
}

package io.nuls.token.interfaces;

import io.nuls.contract.sdk.annotation.View;

import java.math.BigInteger;


public interface INRC721Metadata {
    /**
     * @return A descriptive name for a collection of NFTs in this contract
     */
    @View
    String name() ;

    /**
     * @return An abbreviated name for NFTs in this contract
     */
    @View
    String symbol() ;

    /**
     * @return A distinct Uniform Resource Identifier (URI) for a given asset.
     *         NULL if `tokenId` is not a valid NFT.
     */
    @View
    String tokenURI(BigInteger tokenId) ;
}

package io.nuls.token.interfaces;

import io.nuls.contract.sdk.Address;
import io.nuls.contract.sdk.annotation.View;

import java.math.BigInteger;


public interface INRC721Enumerable {
    /**
     * Count NFTs tracked by this contract
     * @return A count of valid NFTs tracked by this contract, where each one of
     *         them has an assigned and queryable owner
     */
    @View
    int totalSupply();

    /**
     * Enumerate valid NFTs
     * @param index A counter less than `totalSupply()`
     * @return The token identifier for the `index` NFT,
     *  (sort order not specified), NULL if `index` >= `totalSupply()`.
     */
    @View
    BigInteger tokenByIndex(int index);

    /**
     * Enumerate NFTs assigned to an owner
     * @param owner An address where we are interested in NFTs owned by them
     * @param index A counter less than `balanceOf(_owner)`
     * @return The token identifier for the `index` NFT assigned to `owner`,
     *   (sort order not specified), NULL if `index` >= `balanceOf(owner)` or invalid NFTs.
     */
    @View
    BigInteger tokenOfOwnerByIndex(Address owner, int index);
}