import type { Engine } from "@xo-cash/engine";
import type { ScriptHashData, UnspentOutputData } from "@xo-cash/state";

/**
 * Template and output identifiers resolved from script hash storage.
 */
export type UnspentOutputMetadata = {
  templateIdentifier?: string;
  outputIdentifier?: string;
};

export type UnspentOutputWithMetadata = UnspentOutputData &
  UnspentOutputMetadata;

/**
 * Builds a lookup map from script hash to its stored metadata.
 */
export const buildScriptHashDataMap = async (
  engine: Engine,
): Promise<Map<string, ScriptHashData>> => {
  const scriptHashes = await engine.listScriptHashes();
  const scriptHashDataByScriptHash = new Map<string, ScriptHashData>();

  for (const scriptHashRow of scriptHashes) {
    scriptHashDataByScriptHash.set(scriptHashRow.scriptHash, scriptHashRow);
  }

  return scriptHashDataByScriptHash;
};

/**
 * Resolves template/output metadata for a single UTXO via its script hash.
 */
export const getUnspentOutputMetadata = (
  utxo: UnspentOutputData,
  scriptHashDataByScriptHash: Map<string, ScriptHashData>,
): UnspentOutputMetadata => {
  const scriptRow = scriptHashDataByScriptHash.get(utxo.scriptHash);

  if (scriptRow === undefined) {
    return {};
  }

  return {
    templateIdentifier: scriptRow.templateIdentifier,
    outputIdentifier: scriptRow.outputIdentifier,
  };
};

/**
 * Returns a UTXO enriched with template/output metadata from script hash storage.
 */
export const enrichUnspentOutput = (
  utxo: UnspentOutputData,
  scriptHashDataByScriptHash: Map<string, ScriptHashData>,
): UnspentOutputWithMetadata => ({
  ...utxo,
  ...getUnspentOutputMetadata(utxo, scriptHashDataByScriptHash),
});