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/**
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 * Hex encoding/decoding utilities for Git object IDs
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 */
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/**
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 * Convert bytes to lowercase hex string
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 * @param bytes - Uint8Array to convert
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 * @returns Lowercase hex string
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 */
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export function bytesToHex(bytes: Uint8Array): string {
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  return Array.from(bytes)
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    .map((b) => b.toString(16).padStart(2, "0"))
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    .join("");
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}
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/**
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 * Convert hex string to bytes
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 * @param hex - Hex string (case insensitive)
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 * @returns Uint8Array of bytes
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 */
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export function hexToBytes(hex: string): Uint8Array {
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  if (hex.length % 2 !== 0) {
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    throw new Error("Invalid hex string: odd length");
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  }
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  const bytes = new Uint8Array(hex.length / 2);
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  for (let i = 0; i < hex.length; i += 2) {
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    bytes[i / 2] = parseInt(hex.substr(i, 2), 16);
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  }
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  return bytes;
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}
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/**
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 * Check if a string is a valid Git OID (40 hex chars)
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 * @param oid - String to check
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 * @returns true if valid Git OID
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 */
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export function isValidOid(oid: string): boolean {
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  return /^[0-9a-f]{40}$/i.test(oid);
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}
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/**
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 * Get the zero OID (40 zeros)
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 * @returns "0000000000000000000000000000000000000000"
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 */
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export function zeroOid(): string {
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  return "0".repeat(40);
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}