gno.land/r/g17mgsf396a9ysyj4z22ft0zc0xv8ka6dns4fx7f/tokenfactory⧉

1package tokenfactory23import (4	"chain"5	"chain/banker"6	"chain/runtime/unsafe"78	"gno.land/p/nt/avl/v0"9	"gno.land/p/nt/grc20/v0"10	"gno.land/p/nt/ownable/v0"11	"gno.land/p/nt/seqid/v0"12	"gno.land/r/nt/grc20reg/v0"13)1415const creationFee = int64(40000000) // 40 GNOT1617var (18	instances   avl.Tree19	nextTokenID seqid.ID2021	feeRecipient = address(22		"g17mgsf396a9ysyj4z22ft0zc0xv8ka6dns4fx7f",23	)24)2526type instance struct {27	token  *grc20.Token28	ledger *grc20.PrivateLedger29	admin  *ownable.Ownable30}3132// CreationFee returns the token creation fee in ugnot.33func CreationFee() int64 {34	return creationFee35}3637// FeeRecipient returns the address receiving creation fees.38func FeeRecipient() address {39	return feeRecipient40}4142// CreateToken creates a new GRC20 token.43//44// initialSupply is expressed in the token's smallest unit.45//46// Example:47// decimals = 648// initialSupply = 100000000000049// => 1,000,000 tokens.50//51// A direct user call must attach exactly 40 GNOT.52func CreateToken(53	cur realm,54	name string,55	symbol string,56	decimals int,57	initialSupply int64,58) string {59	// Creation must come directly from a user wallet.60	if !cur.Previous().IsUserCall() {61		panic("token creation must be called directly by a user")62	}6364	// Exactly 40 GNOT must be attached.65	if unsafe.OriginSend().AmountOf("ugnot") != creationFee {66		panic("invalid token creation fee")67	}6869	if name == "" {70		panic("token name cannot be empty")71	}7273	if symbol == "" {74		panic("token symbol cannot be empty")75	}7677	if decimals < 0 {78		panic("decimals cannot be negative")79	}8081	if initialSupply < 0 {82		panic("initial supply cannot be negative")83	}8485	if instances.Has(symbol) {86		panic("token symbol already exists")87	}8889	creator := cur.Previous().Address()9091	token, ledger := grc20.NewToken(92		name,93		symbol,94		decimals,95		nextTokenID.Next(),96		cur,97	)9899	// Mint the user-selected initial supply directly100	// to the wallet that created the token.101	if initialSupply > 0 {102		checkErr(103			ledger.Mint(104				creator,105				initialSupply,106			),107		)108	}109110	inst := instance{111		token:  token,112		ledger: ledger,113		admin:  ownable.NewWithAddress(creator),114	}115116	instances.Set(117		symbol,118		&inst,119	)120121	// Register the token in the canonical GRC20 registry.122	grc20reg.Register(123		cross(cur),124		token,125		symbol,126	)127128	// Transfer the 40 GNOT creation fee129	// from the Token Factory realm directly130	// to the GNO Explorer fee recipient.131	banker_ := banker.NewBanker(132		banker.BankerTypeRealmSend,133		cur,134	)135136	feeCoins := chain.NewCoins(137		chain.NewCoin(138			"ugnot",139			creationFee,140		),141	)142143	banker_.SendCoins(144		cur.Address(),145		feeRecipient,146		feeCoins,147	)148149	return token.ID()150}151152// Bank returns the GRC20 token instance.153func Bank(symbol string) *grc20.Token {154	return mustGetInstance(symbol).token155}156157// TokenID returns the unique GRC20 token ID.158func TokenID(symbol string) string {159	return mustGetInstance(symbol).token.ID()160}161162// TotalSupply returns the total token supply.163func TotalSupply(symbol string) int64 {164	return mustGetInstance(symbol).165		token.166		ReadonlyTeller().167		TotalSupply()168}169170// BalanceOf returns the token balance of an address.171func BalanceOf(172	symbol string,173	owner address,174) int64 {175	return mustGetInstance(symbol).176		token.177		ReadonlyTeller().178		BalanceOf(owner)179}180181// Mint allows the token owner to mint additional tokens.182func Mint(183	cur realm,184	symbol string,185	to address,186	amount int64,187) {188	if amount <= 0 {189		panic("mint amount must be greater than zero")190	}191192	inst := mustGetInstance(symbol)193194	inst.admin.AssertOwnedBy(195		cur.Previous().Address(),196	)197198	checkErr(199		inst.ledger.Mint(200			to,201			amount,202		),203	)204}205206// Burn allows the token owner to burn tokens.207func Burn(208	cur realm,209	symbol string,210	from address,211	amount int64,212) {213	if amount <= 0 {214		panic("burn amount must be greater than zero")215	}216217	inst := mustGetInstance(symbol)218219	inst.admin.AssertOwnedBy(220		cur.Previous().Address(),221	)222223	checkErr(224		inst.ledger.Burn(225			from,226			amount,227		),228	)229}230231// TransferTokenOwnership transfers administration232// of a token to another address.233func TransferTokenOwnership(234	cur realm,235	symbol string,236	newOwner address,237) {238	inst := mustGetInstance(symbol)239240	checkErr(241		inst.admin.TransferOwnership(242			0,243			cur,244			newOwner,245		),246	)247}248249// DropTokenOwnership permanently removes250// the administrator of the token.251func DropTokenOwnership(252	cur realm,253	symbol string,254) {255	inst := mustGetInstance(symbol)256257	checkErr(258		inst.admin.DropOwnership(259			0,260			cur,261		),262	)263}264265func mustGetInstance(266	symbol string,267) *instance {268	value := instances.Get(symbol)269270	if value == nil {271		panic("token does not exist")272	}273274	return value.(*instance)275}276277func checkErr(err error) {278	if err != nil {279		panic(err.Error())280	}281}