feat: add on-chain watch-only functionality

lnbits/extensions/watchonly/static/js/utils.js

@@ -0,0 +1,99 @@
+const blockTimeToDate = blockTime =>
+  blockTime ? moment(blockTime * 1000).format('LLL') : ''
+
+const currentDateTime = () => moment().format('LLL')
+
+const sleep = ms => new Promise(r => setTimeout(r, ms))
+
+const retryWithDelay = async function (fn, retryCount = 0) {
+  try {
+    await sleep(25)
+    // Do not return the call directly, use result.
+    // Otherwise the error will not be cought in this try-catch block.
+    const result = await fn()
+    return result
+  } catch (err) {
+    if (retryCount > 100) throw err
+    await sleep((retryCount + 1) * 1000)
+    return retryWithDelay(fn, retryCount + 1)
+  }
+}
+
+const txSize = tx => {
+  // https://bitcoinops.org/en/tools/calc-size/
+  // overhead size
+  const nVersion = 4
+  const inCount = 1
+  const outCount = 1
+  const nlockTime = 4
+  const hasSegwit = !!tx.inputs.find(inp =>
+    ['p2wsh', 'p2wpkh', 'p2tr'].includes(inp.accountType)
+  )
+  const segwitFlag = hasSegwit ? 0.5 : 0
+  const overheadSize = nVersion + inCount + outCount + nlockTime + segwitFlag
+
+  // inputs size
+  const outpoint = 36 // txId plus vout index number
+  const scriptSigLength = 1
+  const nSequence = 4
+  const inputsSize = tx.inputs.reduce((t, inp) => {
+    const scriptSig =
+      inp.accountType === 'p2pkh' ? 107 : inp.accountType === 'p2sh' ? 254 : 0
+    const witnessItemCount = hasSegwit ? 0.25 : 0
+    const witnessItems =
+      inp.accountType === 'p2wpkh'
+        ? 27
+        : inp.accountType === 'p2wsh'
+        ? 63.5
+        : inp.accountType === 'p2tr'
+        ? 16.5
+        : 0
+    t +=
+      outpoint +
+      scriptSigLength +
+      nSequence +
+      scriptSig +
+      witnessItemCount +
+      witnessItems
+    return t
+  }, 0)
+
+  // outputs size
+  const nValue = 8
+  const scriptPubKeyLength = 1
+
+  const outputsSize = tx.outputs.reduce((t, out) => {
+    const type = guessAddressType(out.address)
+
+    const scriptPubKey =
+      type === 'p2pkh'
+        ? 25
+        : type === 'p2wpkh'
+        ? 22
+        : type === 'p2sh'
+        ? 23
+        : type === 'p2wsh'
+        ? 34
+        : 34 // default to the largest size (p2tr included)
+    t += nValue + scriptPubKeyLength + scriptPubKey
+    return t
+  }, 0)
+
+  return overheadSize + inputsSize + outputsSize
+}
+const guessAddressType = (a = '') => {
+  if (a.startsWith('1') || a.startsWith('n')) return 'p2pkh'
+  if (a.startsWith('3') || a.startsWith('2')) return 'p2sh'
+  if (a.startsWith('bc1q') || a.startsWith('tb1q'))
+    return a.length === 42 ? 'p2wpkh' : 'p2wsh'
+  if (a.startsWith('bc1p') || a.startsWith('tb1p')) return 'p2tr'
+}
+// bc1qwpdwyaqweavs5fpa8rujqaxmrmt9lvmydmcnt7
+const ACCOUNT_TYPES = {
+  p2tr: 'Taproot, BIP86, P2TR, Bech32m',
+  p2wpkh: 'SegWit, BIP84, P2WPKH, Bech32',
+  p2sh: 'BIP49, P2SH-P2WPKH, Base58',
+  p2pkh: 'Legacy, BIP44, P2PKH, Base58'
+}
+
+const getAccountDescription = type => ACCOUNT_TYPES[type] || 'nonstandard'