use super::super::config::Base64DecodeConfig;
use super::super::error::Base64Error;
use super::decode_into::decode_into;
use super::output::Base64DecodeOutput;
#[inline]
pub fn decode(
config: &Base64DecodeConfig,
data: impl AsRef<[u8]>,
) -> Result<Base64DecodeOutput, Base64Error> {
let data = data.as_ref();
if data.is_empty() {
return Ok(Base64DecodeOutput { inner: Vec::new() });
}
let mut padding_count = 0;
for &byte in data.iter().rev() {
if config.padding == Some(byte) {
padding_count += 1;
} else {
break;
}
}
if padding_count > 2 {
return Err(Base64Error::InvalidPadding);
}
let clean_len = data.len() - padding_count;
if clean_len == 0 {
return Ok(Base64DecodeOutput { inner: Vec::new() });
}
let output_len = (clean_len * 3) / 4;
let mut output = Vec::with_capacity(output_len);
unsafe { output.set_len(output_len) };
let _ = decode_into(config, &mut output, data)?;
Ok(Base64DecodeOutput { inner: output })
}