gno.land/p/samcrew/launchpad/currency/v1⧉

1// Package currency moves launchpad payments in native ugnot or any GRC20 token.2//3// Every function takes the calling realm's own cur as rlm, so funds always move4// to or from that realm and never from a realm the caller can name.5package currency67import (8	"chain"9	"chain/banker"10	"chain/runtime/unsafe"1112	"gno.land/p/nt/grc20/v0"13	"gno.land/p/samcrew/launchpad/meta/v1"14)1516const NativeDenom = "ugnot"1718// CollectNative accepts exactly amount ugnot attached by the user who called19// the realm directly, and returns that user. Coins attached to a call that20// reaches the realm through another realm belong to that other realm and are21// refused.22func CollectNative(_ int, rlm realm, amount int64) address {23	if !rlm.IsCurrent() {24		panic("launchpad/currency: rlm is not the current realm")25	}26	prev := rlm.Previous()27	if !prev.IsUserCall() {28		panic("launchpad/currency: native payment must be attached to a direct user call")29	}30	sent := unsafe.OriginSend()31	if len(sent) != 1 || sent[0].Denom != NativeDenom || sent[0].Amount != amount {32		panic("launchpad/currency: attached coins do not match the amount due")33	}34	return prev.Address()35}3637// AssertNoCoins refuses coins attached by a user who calls the realm directly:38// they would land in the realm, which keeps no account of them. Coins attached39// to a call that reaches the realm through another realm went to that other40// realm and are its business. The pinned chain also fails a call whose coins41// no code reads; this check does not depend on that.42func AssertNoCoins(_ int, rlm realm) {43	if !rlm.IsCurrent() {44		panic("launchpad/currency: rlm is not the current realm")45	}46	if rlm.Previous().IsUserCall() && len(unsafe.OriginSend()) != 0 {47		panic("launchpad/currency: this call does not accept coins")48	}49}5051// A token ledger keys balances by the receiver's text, so a receiver in any52// spelling but the one the chain gives a caller would be paid into a balance53// no caller can reach.54func assertReceiver(to address) {55	if !meta.ValidAddress(to) {56		panic("launchpad/currency: invalid receiver")57	}58}5960// PayNative sends amount ugnot from the calling realm.61func PayNative(_ int, rlm realm, to address, amount int64) {62	if !rlm.IsCurrent() {63		panic("launchpad/currency: rlm is not the current realm")64	}65	assertReceiver(to)66	banker.NewBanker(banker.BankerTypeRealmSend, rlm).67		SendCoins(rlm.Address(), to, chain.Coins{{NativeDenom, amount}})68}6970// CollectToken pulls amount of tok from the realm's direct caller, who must have71// approved the calling realm, and returns that caller.72func CollectToken(_ int, rlm realm, tok *grc20.Token, amount int64) address {73	if !rlm.IsCurrent() {74		panic("launchpad/currency: rlm is not the current realm")75	}76	AssertNoCoins(0, rlm)77	payer := rlm.Previous().Address()78	if err := tok.RealmTeller(0, rlm).TransferFrom(0, rlm, payer, rlm.Address(), amount); err != nil {79		panic(err.Error())80	}81	return payer82}8384// PayToken sends amount of tok from the calling realm's own balance.85func PayToken(_ int, rlm realm, tok *grc20.Token, to address, amount int64) {86	if !rlm.IsCurrent() {87		panic("launchpad/currency: rlm is not the current realm")88	}89	assertReceiver(to)90	if err := tok.RealmTeller(0, rlm).Transfer(0, rlm, to, amount); err != nil {91		panic(err.Error())92	}93}94