Index delegates and sat locations

src/adapters/local-ord-api.js

@@ -1,3 +1,4 @@
+import { offsetOf } from './sats.js';
 import { Tx } from '@cmdcode/tapscript';
 import { readEnvelope } from './inscription.js';
 import { MetadataIndex } from './metadata-index.js';
@@ -13,6 +14,15 @@ export class LocalOrdAPI {
     const chain = this.chain, index = this.index ?? new MetadataIndex(chain);
     const blockInfo = block => ({ height: block.height, hash: block.hash, previous: block.previous,
       time: block.time, txids: block.raws.map(raw => Tx.util.getTxid(raw)) });
+    if (root === 'local' && kind === 'sat' && /^(0|[1-9][0-9]*)$/.test(key ?? '')) {
+      const sat = Number(key), events = index.events.filter(e => e.sat === sat);
+      const coin = [...index.utxos.values()].find(c => c.ranges.some(([a,b]) => sat >= a && sat < b));
+      if (coin || events.length) return response({ sat, model: 'synthetic-local-fifo', inscriptions: events.map(e => e.id), location: coin ? { txid: coin.txid, vout: coin.vout, offset: offsetOf(coin.ranges, sat) } : null, ranges: coin?.ranges ?? [] });
+    }
+    if (root === 'local' && kind === 'utxo') {
+      const coin = index.utxos.get(key);
+      if (coin) return response({ ...coin, inscriptions: index.events.filter(e => e.location?.txid === coin.txid && e.location.vout === coin.vout).map(e => e.id) });
+    }
     if (url.pathname === '/local/metadata-index') return response({ ...index.stats, events: index.events });
     if (url.pathname === '/local/protocols') return response(index.protocols.map(protocol => {
       const events = index.forProtocol(protocol);
@@ -32,15 +42,16 @@ export class LocalOrdAPI {
     const event = index.events.find(e => e.id === id);
     if (event) {
       if (root === 'content') {
-        const record = chain.transactions.get(id.slice(0, -2));
-        const item = readEnvelope(Tx.decode(record.raw).vin[0].witness);
-        return response(item.bytes, item.contentType);
+        return resolveContent(index, id, target => {
+          const record = chain.transactions.get(target.replace(/i[0-9]+$/, ''));
+          return readEnvelope(Tx.decode(record.raw).vin.find(i => i.witness?.length === 3).witness);
+        });
       }
       if (kind === 'inscription') return response(event);
       // ord's metadata endpoint returns CBOR hex. Expose decoded JSON in inscription/index responses.
       if (kind === 'metadata') {
         const record = chain.transactions.get(id.slice(0, -2));
-        const item = readEnvelope(Tx.decode(record.raw).vin[0].witness);
+        const item = readEnvelope(Tx.decode(record.raw).vin.find(i => i.witness?.length === 3).witness);
         return response(item.metadataBytes ? Array.from(item.metadataBytes, b => b.toString(16).padStart(2, '0')).join('') : null);
       }
       if (kind === 'parents') return response({ ids: event.parent ? [event.parent] : [] });
@@ -49,3 +60,17 @@ export class LocalOrdAPI {
     return response({ error: 'Not found in this local lab.' }, undefined, 404);
   }
 }
+
+// Identity is the requested id even when the bytes/type come from another inscription.
+export function resolveContent(index, id, read) {
+  const visited = new Set(); let target = id;
+  while (true) {
+    if (visited.has(target)) return { status: 508, contentType: 'application/json', body: { error: 'Delegate loop detected.' } };
+    visited.add(target);
+    const event = index.events.find(e => e.id === target);
+    if (!event) return { status: 404, contentType: 'application/json', body: { error: 'Delegate target not found.' } };
+    if (event.delegate) { target = event.delegate; continue; }
+    const item = read(target);
+    return { status: 200, contentType: item.contentType, body: item.bytes, inscriptionId: id, contentId: target };
+  }
+}

src/adapters/metadata-index.js

@@ -1,3 +1,4 @@
+import { outputRanges, satAt, offsetOf } from './sats.js';
 import { Tx } from '@cmdcode/tapscript';
 import { readEnvelope } from './inscription.js';
 
@@ -6,12 +7,22 @@ import { readEnvelope } from './inscription.js';
 export class MetadataIndex {
   constructor(chain) {
     this.events = [];
+    this.utxos = new Map();
     const visit = (raw, height, block) => {
       const tx = Tx.decode(raw);
-      if (tx.vin[0]?.witness?.length !== 3) return;
-      const item = readEnvelope(tx.vin[0].witness);
+      const txid = Tx.util.getTxid(tx), coinbase = tx.vin[0].txid === '0'.repeat(64);
+      const coins = coinbase ? [] : tx.vin.map(i => this.utxos.get(`${i.txid}:${i.vout}`));
+      const ranges = outputRanges(tx, coins, height, coinbase);
+      tx.vin.forEach(i => this.utxos.delete(`${i.txid}:${i.vout}`));
+      tx.vout.forEach((out, vout) => this.utxos.set(`${txid}:${vout}`, { txid, vout, value: Number(out.value), ranges: ranges[vout] }));
+      const witness = tx.vin.find(i => i.witness?.length === 3)?.witness;
+      if (!witness) return;
+      const item = readEnvelope(witness);
+      const pointer = BigInt(item.pointer ?? 0), total = tx.vout.reduce((n, o) => n + Number(o.value), 0);
+      const sat = satAt(ranges.flat(), pointer < BigInt(total) ? Number(pointer) : 0);
       const metadata = item.metadata;
-      this.events.push({ id: `${Tx.util.getTxid(tx)}i0`, contentType: item.contentType,
+      this.events.push({ id: `${Tx.util.getTxid(tx)}i0`, contentType: item.contentType, delegate: item.delegate, pointer: item.pointer, sat,
+        reinscriptionPosition: this.events.filter(e => e.sat === sat).length,
         status: height === null ? 'pending' : 'confirmed', height, block,
         metadata: metadata ?? null, hasMetadata: metadata !== undefined, parent: item.parent,
         protocol: metadata && !Array.isArray(metadata) && typeof metadata === 'object' &&
@@ -19,6 +30,15 @@ export class MetadataIndex {
     };
     for (const block of chain.blocks) for (const raw of block.raws) visit(raw, block.height, block.hash);
     for (const raw of chain.mempool) visit(raw, null, null);
+    for (const event of this.events) {
+      event.location = null;
+      for (const coin of this.utxos.values()) {
+        const offset = offsetOf(coin.ranges, event.sat);
+        if (offset !== null) { event.location = { txid: coin.txid, vout: coin.vout, offset }; break; }
+      }
+      event.delegatedBy = this.events.filter(e => e.delegate === event.id).map(e => e.id);
+      event.inscriptions = this.events.filter(e => e.sat === event.sat).map(e => e.id);
+    }
   }
   forProtocol(name) { return this.events.filter(e => e.protocol === name); }
   get protocols() { return [...new Set(this.events.filter(e => e.protocol !== null).map(e => e.protocol))].sort(); }