import { readFile, writeFile } from "node:fs/promises";

async function cleanCsv() {
  const filePath = "measure.csv";
  try {
    const content = await readFile(filePath, "utf-8");
    const lines = content.split("\n");
    if (lines.length === 0) return;

    const cleanedLines = lines.map(line => {
      if (!line.trim()) return "";
      
      // Basic CSV split (Note: does not handle quoted commas, 
      // but based on our previous read, the columns we need are early and simple)
      const cols = line.split(",");
      
      // Indices: 상수(1), songno(3), diff(4) -> 0-based: 1, 3, 4
      const selected = [cols[1], cols[3], cols[4]];
      return selected.join(",");
    }).filter(line => line !== "");

    await writeFile(filePath, cleanedLines.join("\n"));
    console.log("measure.csv cleaned successfully.");
  } catch (error) {
    console.error("Error cleaning CSV:", error);
  }
}

cleanCsv();