private/convertToBase32.ps1
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function convertToBase32 { param($bytes) # Base32 alphabet: A-Z and 2-7 (32 characters total) # Each character represents 5 bits of data (2^5 = 32 possible values) $alphabet = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ234567' $result = '' # CRITICAL: Buffer to accumulate bits before converting to Base32 # We need to handle bits in groups of 5 (Base32) while input is in groups of 8 (bytes) $buffer = 0 $bitsLeft = 0 # Process each input byte (8 bits) foreach ($byte in $bytes) { # CRITICAL: Add 8 bits to the buffer # 1. Shift existing bits left by 8 to make room for new bits # 2. OR with new byte to add it to the rightmost position $buffer = ($buffer -shl 8) -bor $byte $bitsLeft += 8 # CRITICAL: Extract Base32 characters while we have enough bits # Each Base32 character needs 5 bits while ($bitsLeft -ge 5) { $bitsLeft -= 5 # Extract 5 bits from the buffer: # 1. Shift right to get the highest 5 bits # 2. AND with 0x1F (31) to get just those 5 bits $index = ($buffer -shr $bitsLeft) -band 0x1F # Convert to Base32 character $result += $alphabet[$index] } } # CRITICAL: Handle any remaining bits (less than 5) # This ensures we don't lose any data at the end if ($bitsLeft -gt 0) { # Shift left to align remaining bits # AND with 0x1F to get just those bits $index = ($buffer -shl (5 - $bitsLeft)) -band 0x1F $result += $alphabet[$index] } $result } function convertFromBase32 { param($base32String) # Base32 alphabet: A-Z and 2-7 (32 characters total) # Each character represents 5 bits of data (2^5 = 32 possible values) $alphabet = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ234567' $byteArray = @() # CRITICAL: Buffer to accumulate bits before converting to bytes # We need to handle bits in groups of 5 (Base32) while output is in groups of 8 (bytes) $buffer = 0 $bitsLeft = 0 # Remove padding and convert to uppercase $base32String = $base32String.ToUpperInvariant() -replace '=+$' # Process each Base32 character for ($i = 0; $i -lt $base32String.Length; $i++) { $char = $base32String[$i] # Get the 5-bit value for this character $value = $alphabet.IndexOf($char) if ($value -eq -1) { continue } # CRITICAL: Add 5 bits to the buffer # 1. Shift existing bits left by 5 to make room for new bits # 2. OR with new value to add it to the rightmost position $buffer = ($buffer -shl 5) -bor $value $bitsLeft += 5 # CRITICAL: Extract bytes when we have enough bits # Each byte needs 8 bits if ($bitsLeft -ge 8) { $bitsLeft -= 8 # Extract 8 bits from the buffer: # 1. Shift right to get the highest 8 bits # 2. AND with 0xFF (255) to get just those 8 bits $byte = ($buffer -shr $bitsLeft) -band 0xFF $byteArray += [byte]$byte } } $byteArray } |