#include "base64.h"

#include "simdutf.h"

#include <kj/debug.h>

namespace workerd::api {

jsg::JsBufferSource Base64Module::decodeArray(jsg::Lock& js, jsg::JsBufferSource input) {
  auto ptr = input.asArrayPtr();
  auto size = simdutf::maximal_binary_length_from_base64(
      reinterpret_cast<const char*>(ptr.begin()), ptr.size());
  auto buf = jsg::JsArrayBuffer::create(js, size);
  auto result = simdutf::base64_to_binary(ptr.asChars().begin(), input.size(),
      buf.asArrayPtr().asChars().begin(), simdutf::base64_default);
  JSG_REQUIRE(result.error == simdutf::SUCCESS, DOMSyntaxError,
      kj::str("Invalid base64 at position ", result.count, ": ",
          simdutf::error_to_string(result.error).data()));
  KJ_ASSERT(result.count <= size);
  buf = buf.slice(js, result.count);
  return jsg::JsBufferSource(buf);
}

jsg::JsBufferSource Base64Module::encodeArray(jsg::Lock& js, jsg::JsBufferSource input) {
  auto size = simdutf::base64_length_from_binary(input.size());
  auto buf = jsg::JsArrayBuffer::create(js, size);
  auto out_size = simdutf::binary_to_base64(input.asArrayPtr().asChars().begin(), input.size(),
      buf.asArrayPtr().asChars().begin(), simdutf::base64_default);
  KJ_ASSERT(out_size <= size);
  buf = buf.slice(js, out_size);
  return jsg::JsBufferSource(buf);
}

jsg::JsString Base64Module::encodeArrayToString(jsg::Lock& js, jsg::JsBufferSource input) {
  KJ_ASSERT(input.size() < 256 * 1024 * 1024);
  auto size = simdutf::base64_length_from_binary(input.size());
  kj::SmallArray<char, 1024> buf(size);
  auto out_size = simdutf::binary_to_base64(
      input.asArrayPtr().asChars().begin(), input.size(), buf.begin(), simdutf::base64_default);
  KJ_ASSERT(out_size <= size);
  return js.str(buf.first(out_size));
}

}  // namespace workerd::api