problem: can't get change address

src/lib/event_helpers/rockets.ts

@@ -1,5 +1,5 @@
 import { getAuthorizedZapper } from '@/helpers';
-import { BitcoinTipTag, txs } from '@/stores/bitcoin';
+import { BitcoinTipTag, txo, txs } from '@/stores/bitcoin';
 import { NDKEvent, type NDKTag } from '@nostr-dev-kit/ndk';
 import validate from 'bitcoin-address-validation';
 import { sha256 } from 'js-sha256';
@@ -47,7 +47,6 @@ export class Rocket {
 	}
 	UpsertMeritTransfer(request: MeritPurchase): NDKEvent | undefined {
 		let event: NDKEvent | undefined = undefined;
-		let fatal = false;
 		if (this.PendingAMRAuctionsMap().get(request.auction.ID())) {
 			this.PrepareForUpdate();
 			let _event = new NDKEvent(this.Event.ndk, this.Event.rawEvent());
@@ -62,7 +61,7 @@ export class Rocket {
 					_event.tags.push(t);
 				}
 			}
-			_event.tags.push(['proof_raw', `txid:${request.txid}`]);
+			_event.tags.push(['proof_raw', `txid:${request.tx.ID}`]);
 
 			let modifiedMerits: Map<string, RocketAMR> = new Map();
 			for (let id of request.auction.AMRIDs) {
@@ -86,8 +85,29 @@ export class Rocket {
 			}
 			_event.tags.push([
 				'swap',
-				`${request.auction.Merits}:${request.sats}:${Math.floor(new Date().getTime() / 1000)}`
+				`${request.auction.Merits}:${request.tx.Amount}:${Math.floor(new Date().getTime() / 1000)}`
 			]);
+			let existingAssociation = this.BitcoinAssociations().get(request.tx.From);
+			if (
+				!existingAssociation ||
+				(existingAssociation && existingAssociation.Pubkey != request.buyer)
+			) {
+				return event;
+			}
+			if (request.tx.Change) {
+				let existingAssociations = this.BitcoinAssociations();
+				_event.removeTag('address');
+				for (let [_, ba] of existingAssociations) {
+					if (ba.Address != request.tx.From) {
+						_event.tags.push(ba.Tag());
+					}
+					if (ba.Address == request.tx.From) {
+						ba.Address = request.tx.Change;
+						_event.tags.push(ba.Tag());
+					}
+				}
+			}
+
 			updateIgnitionAndParentTag(_event);
 			updateBitcoinTip(_event);
 			event = _event;
@@ -863,6 +883,9 @@ export class BitcoinAssociation {
 	Address: string | undefined;
 	Event: NDKEvent;
 	Balance: number;
+	Tag(): NDKTag {
+		return ['address', `${this.Pubkey}:${this.Address}`];
+	}
 	Validate(): boolean {
 		let valid = true;
 		if (this.Pubkey.length != 64) {
@@ -954,19 +977,17 @@ export class Product {
 export class MeritPurchase {
 	auction: AMRAuction;
 	buyer: string;
-	txid: string;
-	sats: number;
+	tx: txo;
 	rocket: Rocket;
 	Validate(): boolean {
 		//todo: at least validate the utxo format
 		return true;
 	}
-	constructor(rocket: Rocket, auction: AMRAuction, buyer: string, txid: string, sats: number) {
+	constructor(rocket: Rocket, auction: AMRAuction, buyer: string, tx: txo) {
 		this.rocket = rocket;
 		this.auction = auction;
 		this.buyer = buyer;
-		this.txid = txid;
-		this.sats = sats;
+		this.tx = tx;
 	}
 }
 

src/lib/stores/bitcoin.ts

@@ -134,6 +134,7 @@ export class txs {
 			let amount = 0;
 			let height = tx.status.block_height ? tx.status.block_height : 0;
 			let txid = tx.txid;
+			let change: string[] = [];
 			for (let vout of tx.vout) {
 				let address = vout.scriptpubkey_address;
 				if (address && address.trim() == this.Address) {
@@ -141,8 +142,11 @@ export class txs {
 					if (value) {
 						amount += parseInt(value, 10);
 					}
+				} else {
+					change.push(address);
 				}
 			}
+
 			for (let vin of tx.vin) {
 				let address = vin.prevout.scriptpubkey_address;
 				if (address && validate(address)) {
@@ -152,9 +156,12 @@ export class txs {
 					t.From = address;
 					t.To = this.Address;
 					t.ID = txid;
+					if (change.length == 1) {
+						t.Change = change[0];
+					}
 					possibles.set(address, t);
 				} else {
-					console.log(156, vin)
+					console.log(156, vin);
 				}
 			}
 		}
@@ -174,5 +181,6 @@ export class txo {
 	To: string;
 	Amount: number;
 	Height: number;
+	Change: string;
 	constructor() {}
 }

src/routes/buymerits/+page.svelte

@@ -7,7 +7,7 @@
 	import { currentUser } from '@/stores/session';
 	import { NDKEvent } from '@nostr-dev-kit/ndk';
 	import { Avatar } from '@nostr-dev-kit/ndk-svelte-components';
-	import { onDestroy } from 'svelte';
+	import { onDestroy, onMount } from 'svelte';
 	import { derived } from 'svelte/store';
 	import AssociateBitcoinAddress from '../../components/AssociateBitcoinAddress.svelte';
 	import Heading from '../../components/Heading.svelte';
@@ -89,7 +89,7 @@
 									for (let [address, txo] of txs.From()) {
 										for (let [_, ba] of r.BitcoinAssociations()) {
 											if (ba.Address == txo.From) {
-												return new MeritPurchase(r, amrAuction, ba.Pubkey, txo.ID, txo.Amount);
+												return new MeritPurchase(r, amrAuction, ba.Pubkey, txo);
 											}
 										}
 									}