@vbyte/btc-dev/src/lib/address/util.ts

Batteries-included toolset for plebian bitcoin development

import { Buff }               from '@vbyte/buff'
import { decode_address }     from './encode.js'
import { get_address_script } from './script.js'

import type {
  AddressConfig,
  AddressConfigEntry,
  AddressInfo,
  ChainNetwork,
  LockScriptType,
} from '@/types/index.js'

const CONFIG_TABLE : AddressConfigEntry[] = [
  [ '1',      'p2pkh',   'main',    20, 'base58',  0x00 ],
  [ '3',      'p2sh',    'main',    20, 'base58',  0x05 ],
  [ 'm',      'p2pkh',   'testnet', 20, 'base58',  0x6F ],
  [ 'n',      'p2pkh',   'testnet', 20, 'base58',  0x6F ],
  [ '2',      'p2sh',    'testnet', 20, 'base58',  0xC4 ],
  [ 'm',      'p2pkh',   'regtest', 20, 'base58',  0x6F ],
  [ 'n',      'p2pkh',   'regtest', 20, 'base58',  0x6F ],
  [ '2',      'p2sh',    'regtest', 20, 'base58',  0xC4 ],
  [ 'bc',     'p2wpkh', 'main',    20, 'bech32',  0    ],
  [ 'tb',     'p2wpkh', 'testnet', 20, 'bech32',  0    ],
  [ 'bcrt',   'p2wpkh', 'regtest', 20, 'bech32',  0    ],
  [ 'bc',     'p2wsh',  'main',    32, 'bech32',  0    ],
  [ 'tb',     'p2wsh',  'testnet', 32, 'bech32',  0    ],
  [ 'bcrt',   'p2wsh',  'regtest', 32, 'bech32',  0    ],
  [ 'bc',     'p2tr',    'main',    32, 'bech32m', 1    ],
  [ 'tb',     'p2tr',    'testnet', 32, 'bech32m', 1    ],
  [ 'bcrt',   'p2tr',    'regtest', 32, 'bech32m', 1    ]
]

/**
 * Lookup an address configuration by its type and network.
 * 
 * @param address_network - The network of the address.
 * @param address_type    - The type of the address.
 * @returns The address information, or null if the address is not recognized.
 */
export function get_address_config (
  address_network : ChainNetwork,
  address_type    : LockScriptType
) : AddressConfig | null {
  // For each configuration in the table,
  for (const [ prefix, type, network, size, format, version ] of CONFIG_TABLE) {
    // Check if the address matches the configuration
    if (type === address_type && network === address_network) {
      // Return the address configuration.
      return { type, prefix, network, size, format, version }
    }
  }
  // If no configuration matches the address, return null.
  return null
}

/**
 * Parse an address into its data and script.
 * 
 * @param address - The address to parse.
 * @returns The address data and script.
 */
export function get_address_info (address : string) : AddressInfo {
  // Decode the address.
  const dec = decode_address(address)
  // For each configuration in the table,
  for (const [ prefix, type, network, size, format, version ] of CONFIG_TABLE) {

    // Check if the address matches the configuration
    if (format  !== dec.format)      continue
    if (size    !== dec.data.length) continue
    if (version !== dec.version)     continue

    if (dec.prefix) {
      if (prefix !== dec.prefix) continue
    } else {
      if (!address.startsWith(prefix)) continue
    }

    // Convert the decoded data into a hex string.
    const data   = Buff.uint(dec.data).hex
    const script = get_address_script(data, type)
    // Return the address configuration and data.
    return { data, script,type, prefix, network, size, format, version }
  }
  // Otherwise, throw an error
  throw new Error('address configuration is invalid')
}