#include "simdutf.h"
#include <initializer_list>
#include <climits>
#include <type_traits>

// Useful for debugging purposes
namespace simdutf {
namespace {

template <typename T> std::string toBinaryString(T b) {
  std::string binary = "";
  T mask = T(1) << (sizeof(T) * CHAR_BIT - 1);
  while (mask > 0) {
    binary += ((b & mask) == 0) ? '0' : '1';
    mask >>= 1;
  }
  return binary;
}
} // namespace
} // namespace simdutf

// Implementations
// The best choice should always come first!
#include "simdutf/arm64.h"
#include "simdutf/icelake.h"
#include "simdutf/haswell.h"
#include "simdutf/westmere.h"
#include "simdutf/ppc64.h"
#include "simdutf/rvv.h"
#include "simdutf/lsx.h"
#include "simdutf/lasx.h"
#include "simdutf/fallback.h" // have it always last.

#include "scalar/utf8.h"
#include "scalar/utf16.h"
#include "scalar/utf32.h"
#include "scalar/base64.h"
#include "scalar/latin1_to_utf8/latin1_to_utf8.h"

namespace simdutf {
bool implementation::supported_by_runtime_system() const {
  uint32_t required_instruction_sets = this->required_instruction_sets();
  uint32_t supported_instruction_sets =
      internal::detect_supported_architectures();
  return ((supported_instruction_sets & required_instruction_sets) ==
          required_instruction_sets);
}

simdutf_warn_unused encoding_type implementation::autodetect_encoding(
    const char *input, size_t length) const noexcept {
  // If there is a BOM, then we trust it.
  auto bom_encoding = simdutf::BOM::check_bom(input, length);
  if (bom_encoding != encoding_type::unspecified) {
    return bom_encoding;
  }
  // UTF8 is common, it includes ASCII, and is commonly represented
  // without a BOM, so if it fits, go with that. Note that it is still
  // possible to get it wrong, we are only 'guessing'. If some has UTF-16
  // data without a BOM, it could pass as UTF-8.
  //
  // An interesting twist might be to check for UTF-16 ASCII first (every
  // other byte is zero).
  if (validate_utf8(input, length)) {
    return encoding_type::UTF8;
  }
  // The next most common encoding that might appear without BOM is probably
  // UTF-16LE, so try that next.
  if ((length % 2) == 0) {
    // important: we need to divide by two
    if (validate_utf16le(reinterpret_cast<const char16_t *>(input),
                         length / 2)) {
      return encoding_type::UTF16_LE;
    }
  }
  if ((length % 4) == 0) {
    if (validate_utf32(reinterpret_cast<const char32_t *>(input), length / 4)) {
      return encoding_type::UTF32_LE;
    }
  }
  return encoding_type::unspecified;
}

namespace internal {
// When there is a single implementation, we should not pay a price
// for dispatching to the best implementation. We should just use the
// one we have. This is a compile-time check.
#define SIMDUTF_SINGLE_IMPLEMENTATION                                          \
  (SIMDUTF_IMPLEMENTATION_ICELAKE + SIMDUTF_IMPLEMENTATION_HASWELL +           \
       SIMDUTF_IMPLEMENTATION_WESTMERE + SIMDUTF_IMPLEMENTATION_ARM64 +        \
       SIMDUTF_IMPLEMENTATION_PPC64 + SIMDUTF_IMPLEMENTATION_LSX +             \
       SIMDUTF_IMPLEMENTATION_LASX + SIMDUTF_IMPLEMENTATION_FALLBACK ==        \
   1)

// Static array of known implementations. We are hoping these get baked into the
// executable without requiring a static initializer.

#if SIMDUTF_IMPLEMENTATION_ICELAKE
static const icelake::implementation *get_icelake_singleton() {
  static const icelake::implementation icelake_singleton{};
  return &icelake_singleton;
}
#endif
#if SIMDUTF_IMPLEMENTATION_HASWELL
static const haswell::implementation *get_haswell_singleton() {
  static const haswell::implementation haswell_singleton{};
  return &haswell_singleton;
}
#endif
#if SIMDUTF_IMPLEMENTATION_WESTMERE
static const westmere::implementation *get_westmere_singleton() {
  static const westmere::implementation westmere_singleton{};
  return &westmere_singleton;
}
#endif
#if SIMDUTF_IMPLEMENTATION_ARM64
static const arm64::implementation *get_arm64_singleton() {
  static const arm64::implementation arm64_singleton{};
  return &arm64_singleton;
}
#endif
#if SIMDUTF_IMPLEMENTATION_PPC64
static const ppc64::implementation *get_ppc64_singleton() {
  static const ppc64::implementation ppc64_singleton{};
  return &ppc64_singleton;
}
#endif
#if SIMDUTF_IMPLEMENTATION_RVV
static const rvv::implementation *get_rvv_singleton() {
  static const rvv::implementation rvv_singleton{};
  return &rvv_singleton;
}
#endif
#if SIMDUTF_IMPLEMENTATION_LSX
static const lsx::implementation *get_lsx_singleton() {
  static const lsx::implementation lsx_singleton{};
  return &lsx_singleton;
}
#endif
#if SIMDUTF_IMPLEMENTATION_LASX
static const lasx::implementation *get_lasx_singleton() {
  static const lasx::implementation lasx_singleton{};
  return &lasx_singleton;
}
#endif
#if SIMDUTF_IMPLEMENTATION_FALLBACK
static const fallback::implementation *get_fallback_singleton() {
  static const fallback::implementation fallback_singleton{};
  return &fallback_singleton;
}
#endif

#if SIMDUTF_SINGLE_IMPLEMENTATION
static const implementation *get_single_implementation() {
  return
  #if SIMDUTF_IMPLEMENTATION_ICELAKE
      get_icelake_singleton();
  #endif
  #if SIMDUTF_IMPLEMENTATION_HASWELL
  get_haswell_singleton();
  #endif
  #if SIMDUTF_IMPLEMENTATION_WESTMERE
  get_westmere_singleton();
  #endif
  #if SIMDUTF_IMPLEMENTATION_ARM64
  get_arm64_singleton();
  #endif
  #if SIMDUTF_IMPLEMENTATION_PPC64
  get_ppc64_singleton();
  #endif
  #if SIMDUTF_IMPLEMENTATION_LSX
  get_lsx_singleton();
  #endif
  #if SIMDUTF_IMPLEMENTATION_LASX
  get_lasx_singleton();
  #endif
  #if SIMDUTF_IMPLEMENTATION_FALLBACK
  get_fallback_singleton();
  #endif
}
#endif

/**
 * @private Detects best supported implementation on first use, and sets it
 */
class detect_best_supported_implementation_on_first_use final
    : public implementation {
public:
  std::string name() const noexcept final { return set_best()->name(); }
  std::string description() const noexcept final {
    return set_best()->description();
  }
  uint32_t required_instruction_sets() const noexcept final {
    return set_best()->required_instruction_sets();
  }

  simdutf_warn_unused int
  detect_encodings(const char *input, size_t length) const noexcept override {
    return set_best()->detect_encodings(input, length);
  }

  simdutf_warn_unused bool
  validate_utf8(const char *buf, size_t len) const noexcept final override {
    return set_best()->validate_utf8(buf, len);
  }

  simdutf_warn_unused result validate_utf8_with_errors(
      const char *buf, size_t len) const noexcept final override {
    return set_best()->validate_utf8_with_errors(buf, len);
  }

  simdutf_warn_unused bool
  validate_ascii(const char *buf, size_t len) const noexcept final override {
    return set_best()->validate_ascii(buf, len);
  }

  simdutf_warn_unused result validate_ascii_with_errors(
      const char *buf, size_t len) const noexcept final override {
    return set_best()->validate_ascii_with_errors(buf, len);
  }

  simdutf_warn_unused bool
  validate_utf16le(const char16_t *buf,
                   size_t len) const noexcept final override {
    return set_best()->validate_utf16le(buf, len);
  }

  simdutf_warn_unused bool
  validate_utf16be(const char16_t *buf,
                   size_t len) const noexcept final override {
    return set_best()->validate_utf16be(buf, len);
  }

  simdutf_warn_unused result validate_utf16le_with_errors(
      const char16_t *buf, size_t len) const noexcept final override {
    return set_best()->validate_utf16le_with_errors(buf, len);
  }

  simdutf_warn_unused result validate_utf16be_with_errors(
      const char16_t *buf, size_t len) const noexcept final override {
    return set_best()->validate_utf16be_with_errors(buf, len);
  }

  simdutf_warn_unused bool
  validate_utf32(const char32_t *buf,
                 size_t len) const noexcept final override {
    return set_best()->validate_utf32(buf, len);
  }

  simdutf_warn_unused result validate_utf32_with_errors(
      const char32_t *buf, size_t len) const noexcept final override {
    return set_best()->validate_utf32_with_errors(buf, len);
  }

  simdutf_warn_unused size_t
  convert_latin1_to_utf8(const char *buf, size_t len,
                         char *utf8_output) const noexcept final override {
    return set_best()->convert_latin1_to_utf8(buf, len, utf8_output);
  }

  simdutf_warn_unused size_t convert_latin1_to_utf16le(
      const char *buf, size_t len,
      char16_t *utf16_output) const noexcept final override {
    return set_best()->convert_latin1_to_utf16le(buf, len, utf16_output);
  }

  simdutf_warn_unused size_t convert_latin1_to_utf16be(
      const char *buf, size_t len,
      char16_t *utf16_output) const noexcept final override {
    return set_best()->convert_latin1_to_utf16be(buf, len, utf16_output);
  }

  simdutf_warn_unused size_t convert_latin1_to_utf32(
      const char *buf, size_t len,
      char32_t *latin1_output) const noexcept final override {
    return set_best()->convert_latin1_to_utf32(buf, len, latin1_output);
  }

  simdutf_warn_unused size_t
  convert_utf8_to_latin1(const char *buf, size_t len,
                         char *latin1_output) const noexcept final override {
    return set_best()->convert_utf8_to_latin1(buf, len, latin1_output);
  }

  simdutf_warn_unused result convert_utf8_to_latin1_with_errors(
      const char *buf, size_t len,
      char *latin1_output) const noexcept final override {
    return set_best()->convert_utf8_to_latin1_with_errors(buf, len,
                                                          latin1_output);
  }

  simdutf_warn_unused size_t convert_valid_utf8_to_latin1(
      const char *buf, size_t len,
      char *latin1_output) const noexcept final override {
    return set_best()->convert_valid_utf8_to_latin1(buf, len, latin1_output);
  }

  simdutf_warn_unused size_t convert_utf8_to_utf16le(
      const char *buf, size_t len,
      char16_t *utf16_output) const noexcept final override {
    return set_best()->convert_utf8_to_utf16le(buf, len, utf16_output);
  }

  simdutf_warn_unused size_t convert_utf8_to_utf16be(
      const char *buf, size_t len,
      char16_t *utf16_output) const noexcept final override {
    return set_best()->convert_utf8_to_utf16be(buf, len, utf16_output);
  }

  simdutf_warn_unused result convert_utf8_to_utf16le_with_errors(
      const char *buf, size_t len,
      char16_t *utf16_output) const noexcept final override {
    return set_best()->convert_utf8_to_utf16le_with_errors(buf, len,
                                                           utf16_output);
  }

  simdutf_warn_unused result convert_utf8_to_utf16be_with_errors(
      const char *buf, size_t len,
      char16_t *utf16_output) const noexcept final override {
    return set_best()->convert_utf8_to_utf16be_with_errors(buf, len,
                                                           utf16_output);
  }

  simdutf_warn_unused size_t convert_valid_utf8_to_utf16le(
      const char *buf, size_t len,
      char16_t *utf16_output) const noexcept final override {
    return set_best()->convert_valid_utf8_to_utf16le(buf, len, utf16_output);
  }

  simdutf_warn_unused size_t convert_valid_utf8_to_utf16be(
      const char *buf, size_t len,
      char16_t *utf16_output) const noexcept final override {
    return set_best()->convert_valid_utf8_to_utf16be(buf, len, utf16_output);
  }

  simdutf_warn_unused size_t
  convert_utf8_to_utf32(const char *buf, size_t len,
                        char32_t *utf32_output) const noexcept final override {
    return set_best()->convert_utf8_to_utf32(buf, len, utf32_output);
  }

  simdutf_warn_unused result convert_utf8_to_utf32_with_errors(
      const char *buf, size_t len,
      char32_t *utf32_output) const noexcept final override {
    return set_best()->convert_utf8_to_utf32_with_errors(buf, len,
                                                         utf32_output);
  }

  simdutf_warn_unused size_t convert_valid_utf8_to_utf32(
      const char *buf, size_t len,
      char32_t *utf32_output) const noexcept final override {
    return set_best()->convert_valid_utf8_to_utf32(buf, len, utf32_output);
  }

  simdutf_warn_unused size_t
  convert_utf16le_to_latin1(const char16_t *buf, size_t len,
                            char *latin1_output) const noexcept final override {
    return set_best()->convert_utf16le_to_latin1(buf, len, latin1_output);
  }

  simdutf_warn_unused size_t
  convert_utf16be_to_latin1(const char16_t *buf, size_t len,
                            char *latin1_output) const noexcept final override {
    return set_best()->convert_utf16be_to_latin1(buf, len, latin1_output);
  }

  simdutf_warn_unused result convert_utf16le_to_latin1_with_errors(
      const char16_t *buf, size_t len,
      char *latin1_output) const noexcept final override {
    return set_best()->convert_utf16le_to_latin1_with_errors(buf, len,
                                                             latin1_output);
  }

  simdutf_warn_unused result convert_utf16be_to_latin1_with_errors(
      const char16_t *buf, size_t len,
      char *latin1_output) const noexcept final override {
    return set_best()->convert_utf16be_to_latin1_with_errors(buf, len,
                                                             latin1_output);
  }

  simdutf_warn_unused size_t convert_valid_utf16le_to_latin1(
      const char16_t *buf, size_t len,
      char *latin1_output) const noexcept final override {
    return set_best()->convert_valid_utf16le_to_latin1(buf, len, latin1_output);
  }

  simdutf_warn_unused size_t convert_valid_utf16be_to_latin1(
      const char16_t *buf, size_t len,
      char *latin1_output) const noexcept final override {
    return set_best()->convert_valid_utf16be_to_latin1(buf, len, latin1_output);
  }

  simdutf_warn_unused size_t
  convert_utf16le_to_utf8(const char16_t *buf, size_t len,
                          char *utf8_output) const noexcept final override {
    return set_best()->convert_utf16le_to_utf8(buf, len, utf8_output);
  }

  simdutf_warn_unused size_t
  convert_utf16be_to_utf8(const char16_t *buf, size_t len,
                          char *utf8_output) const noexcept final override {
    return set_best()->convert_utf16be_to_utf8(buf, len, utf8_output);
  }

  simdutf_warn_unused result convert_utf16le_to_utf8_with_errors(
      const char16_t *buf, size_t len,
      char *utf8_output) const noexcept final override {
    return set_best()->convert_utf16le_to_utf8_with_errors(buf, len,
                                                           utf8_output);
  }

  simdutf_warn_unused result convert_utf16be_to_utf8_with_errors(
      const char16_t *buf, size_t len,
      char *utf8_output) const noexcept final override {
    return set_best()->convert_utf16be_to_utf8_with_errors(buf, len,
                                                           utf8_output);
  }

  simdutf_warn_unused size_t convert_valid_utf16le_to_utf8(
      const char16_t *buf, size_t len,
      char *utf8_output) const noexcept final override {
    return set_best()->convert_valid_utf16le_to_utf8(buf, len, utf8_output);
  }

  simdutf_warn_unused size_t convert_valid_utf16be_to_utf8(
      const char16_t *buf, size_t len,
      char *utf8_output) const noexcept final override {
    return set_best()->convert_valid_utf16be_to_utf8(buf, len, utf8_output);
  }

  simdutf_warn_unused size_t
  convert_utf32_to_latin1(const char32_t *buf, size_t len,
                          char *latin1_output) const noexcept final override {
    return set_best()->convert_utf32_to_latin1(buf, len, latin1_output);
  }

  simdutf_warn_unused result convert_utf32_to_latin1_with_errors(
      const char32_t *buf, size_t len,
      char *latin1_output) const noexcept final override {
    return set_best()->convert_utf32_to_latin1_with_errors(buf, len,
                                                           latin1_output);
  }

  simdutf_warn_unused size_t convert_valid_utf32_to_latin1(
      const char32_t *buf, size_t len,
      char *latin1_output) const noexcept final override {
    return set_best()->convert_utf32_to_latin1(buf, len, latin1_output);
  }

  simdutf_warn_unused size_t
  convert_utf32_to_utf8(const char32_t *buf, size_t len,
                        char *utf8_output) const noexcept final override {
    return set_best()->convert_utf32_to_utf8(buf, len, utf8_output);
  }

  simdutf_warn_unused result convert_utf32_to_utf8_with_errors(
      const char32_t *buf, size_t len,
      char *utf8_output) const noexcept final override {
    return set_best()->convert_utf32_to_utf8_with_errors(buf, len, utf8_output);
  }

  simdutf_warn_unused size_t
  convert_valid_utf32_to_utf8(const char32_t *buf, size_t len,
                              char *utf8_output) const noexcept final override {
    return set_best()->convert_valid_utf32_to_utf8(buf, len, utf8_output);
  }

  simdutf_warn_unused size_t convert_utf32_to_utf16le(
      const char32_t *buf, size_t len,
      char16_t *utf16_output) const noexcept final override {
    return set_best()->convert_utf32_to_utf16le(buf, len, utf16_output);
  }

  simdutf_warn_unused size_t convert_utf32_to_utf16be(
      const char32_t *buf, size_t len,
      char16_t *utf16_output) const noexcept final override {
    return set_best()->convert_utf32_to_utf16be(buf, len, utf16_output);
  }

  simdutf_warn_unused result convert_utf32_to_utf16le_with_errors(
      const char32_t *buf, size_t len,
      char16_t *utf16_output) const noexcept final override {
    return set_best()->convert_utf32_to_utf16le_with_errors(buf, len,
                                                            utf16_output);
  }

  simdutf_warn_unused result convert_utf32_to_utf16be_with_errors(
      const char32_t *buf, size_t len,
      char16_t *utf16_output) const noexcept final override {
    return set_best()->convert_utf32_to_utf16be_with_errors(buf, len,
                                                            utf16_output);
  }

  simdutf_warn_unused size_t convert_valid_utf32_to_utf16le(
      const char32_t *buf, size_t len,
      char16_t *utf16_output) const noexcept final override {
    return set_best()->convert_valid_utf32_to_utf16le(buf, len, utf16_output);
  }

  simdutf_warn_unused size_t convert_valid_utf32_to_utf16be(
      const char32_t *buf, size_t len,
      char16_t *utf16_output) const noexcept final override {
    return set_best()->convert_valid_utf32_to_utf16be(buf, len, utf16_output);
  }

  simdutf_warn_unused size_t convert_utf16le_to_utf32(
      const char16_t *buf, size_t len,
      char32_t *utf32_output) const noexcept final override {
    return set_best()->convert_utf16le_to_utf32(buf, len, utf32_output);
  }

  simdutf_warn_unused size_t convert_utf16be_to_utf32(
      const char16_t *buf, size_t len,
      char32_t *utf32_output) const noexcept final override {
    return set_best()->convert_utf16be_to_utf32(buf, len, utf32_output);
  }

  simdutf_warn_unused result convert_utf16le_to_utf32_with_errors(
      const char16_t *buf, size_t len,
      char32_t *utf32_output) const noexcept final override {
    return set_best()->convert_utf16le_to_utf32_with_errors(buf, len,
                                                            utf32_output);
  }

  simdutf_warn_unused result convert_utf16be_to_utf32_with_errors(
      const char16_t *buf, size_t len,
      char32_t *utf32_output) const noexcept final override {
    return set_best()->convert_utf16be_to_utf32_with_errors(buf, len,
                                                            utf32_output);
  }

  simdutf_warn_unused size_t convert_valid_utf16le_to_utf32(
      const char16_t *buf, size_t len,
      char32_t *utf32_output) const noexcept final override {
    return set_best()->convert_valid_utf16le_to_utf32(buf, len, utf32_output);
  }

  simdutf_warn_unused size_t convert_valid_utf16be_to_utf32(
      const char16_t *buf, size_t len,
      char32_t *utf32_output) const noexcept final override {
    return set_best()->convert_valid_utf16be_to_utf32(buf, len, utf32_output);
  }

  void change_endianness_utf16(const char16_t *buf, size_t len,
                               char16_t *output) const noexcept final override {
    set_best()->change_endianness_utf16(buf, len, output);
  }

  simdutf_warn_unused size_t
  count_utf16le(const char16_t *buf, size_t len) const noexcept final override {
    return set_best()->count_utf16le(buf, len);
  }

  simdutf_warn_unused size_t
  count_utf16be(const char16_t *buf, size_t len) const noexcept final override {
    return set_best()->count_utf16be(buf, len);
  }

  simdutf_warn_unused size_t
  count_utf8(const char *buf, size_t len) const noexcept final override {
    return set_best()->count_utf8(buf, len);
  }

  simdutf_warn_unused size_t
  latin1_length_from_utf8(const char *buf, size_t len) const noexcept override {
    return set_best()->latin1_length_from_utf8(buf, len);
  }

  simdutf_warn_unused size_t
  latin1_length_from_utf16(size_t len) const noexcept override {
    return set_best()->latin1_length_from_utf16(len);
  }

  simdutf_warn_unused size_t
  latin1_length_from_utf32(size_t len) const noexcept override {
    return set_best()->latin1_length_from_utf32(len);
  }

  simdutf_warn_unused size_t
  utf8_length_from_latin1(const char *buf, size_t len) const noexcept override {
    return set_best()->utf8_length_from_latin1(buf, len);
  }

  simdutf_warn_unused size_t utf8_length_from_utf16le(
      const char16_t *buf, size_t len) const noexcept override {
    return set_best()->utf8_length_from_utf16le(buf, len);
  }

  simdutf_warn_unused size_t utf8_length_from_utf16be(
      const char16_t *buf, size_t len) const noexcept override {
    return set_best()->utf8_length_from_utf16be(buf, len);
  }

  simdutf_warn_unused size_t
  utf16_length_from_latin1(size_t len) const noexcept override {
    return set_best()->utf16_length_from_latin1(len);
  }

  simdutf_warn_unused size_t
  utf32_length_from_latin1(size_t len) const noexcept override {
    return set_best()->utf32_length_from_latin1(len);
  }

  simdutf_warn_unused size_t utf32_length_from_utf16le(
      const char16_t *buf, size_t len) const noexcept override {
    return set_best()->utf32_length_from_utf16le(buf, len);
  }

  simdutf_warn_unused size_t utf32_length_from_utf16be(
      const char16_t *buf, size_t len) const noexcept override {
    return set_best()->utf32_length_from_utf16be(buf, len);
  }

  simdutf_warn_unused size_t
  utf16_length_from_utf8(const char *buf, size_t len) const noexcept override {
    return set_best()->utf16_length_from_utf8(buf, len);
  }

  simdutf_warn_unused size_t utf8_length_from_utf32(
      const char32_t *buf, size_t len) const noexcept override {
    return set_best()->utf8_length_from_utf32(buf, len);
  }

  simdutf_warn_unused size_t utf16_length_from_utf32(
      const char32_t *buf, size_t len) const noexcept override {
    return set_best()->utf16_length_from_utf32(buf, len);
  }

  simdutf_warn_unused size_t
  utf32_length_from_utf8(const char *buf, size_t len) const noexcept override {
    return set_best()->utf32_length_from_utf8(buf, len);
  }

  simdutf_warn_unused size_t maximal_binary_length_from_base64(
      const char *input, size_t length) const noexcept override {
    return set_best()->maximal_binary_length_from_base64(input, length);
  }

  simdutf_warn_unused result base64_to_binary(
      const char *input, size_t length, char *output, base64_options options,
      last_chunk_handling_options last_chunk_handling_options =
          last_chunk_handling_options::loose) const noexcept override {
    return set_best()->base64_to_binary(input, length, output, options,
                                        last_chunk_handling_options);
  }

  simdutf_warn_unused full_result base64_to_binary_details(
      const char *input, size_t length, char *output, base64_options options,
      last_chunk_handling_options last_chunk_handling_options =
          last_chunk_handling_options::loose) const noexcept override {
    return set_best()->base64_to_binary_details(input, length, output, options,
                                                last_chunk_handling_options);
  }

  simdutf_warn_unused size_t maximal_binary_length_from_base64(
      const char16_t *input, size_t length) const noexcept override {
    return set_best()->maximal_binary_length_from_base64(input, length);
  }

  simdutf_warn_unused result base64_to_binary(
      const char16_t *input, size_t length, char *output,
      base64_options options,
      last_chunk_handling_options last_chunk_handling_options =
          last_chunk_handling_options::loose) const noexcept override {
    return set_best()->base64_to_binary(input, length, output, options,
                                        last_chunk_handling_options);
  }

  simdutf_warn_unused full_result base64_to_binary_details(
      const char16_t *input, size_t length, char *output,
      base64_options options,
      last_chunk_handling_options last_chunk_handling_options =
          last_chunk_handling_options::loose) const noexcept override {
    return set_best()->base64_to_binary_details(input, length, output, options,
                                                last_chunk_handling_options);
  }

  simdutf_warn_unused size_t base64_length_from_binary(
      size_t length, base64_options options) const noexcept override {
    return set_best()->base64_length_from_binary(length, options);
  }

  size_t binary_to_base64(const char *input, size_t length, char *output,
                          base64_options options) const noexcept override {
    return set_best()->binary_to_base64(input, length, output, options);
  }

  simdutf_really_inline
  detect_best_supported_implementation_on_first_use() noexcept
      : implementation("best_supported_detector",
                       "Detects the best supported implementation and sets it",
                       0) {}

private:
  const implementation *set_best() const noexcept;
};

static_assert(std::is_trivially_destructible<
                  detect_best_supported_implementation_on_first_use>::value,
              "detect_best_supported_implementation_on_first_use should be "
              "trivially destructible");

static const std::initializer_list<const implementation *> &
get_available_implementation_pointers() {
  static const std::initializer_list<const implementation *>
      available_implementation_pointers{
#if SIMDUTF_IMPLEMENTATION_ICELAKE
          get_icelake_singleton(),
#endif
#if SIMDUTF_IMPLEMENTATION_HASWELL
          get_haswell_singleton(),
#endif
#if SIMDUTF_IMPLEMENTATION_WESTMERE
          get_westmere_singleton(),
#endif
#if SIMDUTF_IMPLEMENTATION_ARM64
          get_arm64_singleton(),
#endif
#if SIMDUTF_IMPLEMENTATION_PPC64
          get_ppc64_singleton(),
#endif
#if SIMDUTF_IMPLEMENTATION_RVV
          get_rvv_singleton(),
#endif
#if SIMDUTF_IMPLEMENTATION_LSX
          get_lsx_singleton(),
#endif
#if SIMDUTF_IMPLEMENTATION_LASX
          get_lasx_singleton(),
#endif
#if SIMDUTF_IMPLEMENTATION_FALLBACK
          get_fallback_singleton(),
#endif
      }; // available_implementation_pointers
  return available_implementation_pointers;
}

// So we can return UNSUPPORTED_ARCHITECTURE from the parser when there is no
// support
class unsupported_implementation final : public implementation {
public:
  simdutf_warn_unused int detect_encodings(const char *,
                                           size_t) const noexcept override {
    return encoding_type::unspecified;
  }

  simdutf_warn_unused bool validate_utf8(const char *,
                                         size_t) const noexcept final override {
    return false; // Just refuse to validate. Given that we have a fallback
                  // implementation
    // it seems unlikely that unsupported_implementation will ever be used. If
    // it is used, then it will flag all strings as invalid. The alternative is
    // to return an error_code from which the user has to figure out whether the
    // string is valid UTF-8... which seems like a lot of work just to handle
    // the very unlikely case that we have an unsupported implementation. And,
    // when it does happen (that we have an unsupported implementation), what
    // are the chances that the programmer has a fallback? Given that *we*
    // provide the fallback, it implies that the programmer would need a
    // fallback for our fallback.
  }

  simdutf_warn_unused result validate_utf8_with_errors(
      const char *, size_t) const noexcept final override {
    return result(error_code::OTHER, 0);
  }

  simdutf_warn_unused bool
  validate_ascii(const char *, size_t) const noexcept final override {
    return false;
  }

  simdutf_warn_unused result validate_ascii_with_errors(
      const char *, size_t) const noexcept final override {
    return result(error_code::OTHER, 0);
  }

  simdutf_warn_unused bool
  validate_utf16le(const char16_t *, size_t) const noexcept final override {
    return false;
  }

  simdutf_warn_unused bool
  validate_utf16be(const char16_t *, size_t) const noexcept final override {
    return false;
  }

  simdutf_warn_unused result validate_utf16le_with_errors(
      const char16_t *, size_t) const noexcept final override {
    return result(error_code::OTHER, 0);
  }

  simdutf_warn_unused result validate_utf16be_with_errors(
      const char16_t *, size_t) const noexcept final override {
    return result(error_code::OTHER, 0);
  }

  simdutf_warn_unused bool
  validate_utf32(const char32_t *, size_t) const noexcept final override {
    return false;
  }

  simdutf_warn_unused result validate_utf32_with_errors(
      const char32_t *, size_t) const noexcept final override {
    return result(error_code::OTHER, 0);
  }

  simdutf_warn_unused size_t convert_latin1_to_utf8(
      const char *, size_t, char *) const noexcept final override {
    return 0;
  }

  simdutf_warn_unused size_t convert_latin1_to_utf16le(
      const char *, size_t, char16_t *) const noexcept final override {
    return 0;
  }

  simdutf_warn_unused size_t convert_latin1_to_utf16be(
      const char *, size_t, char16_t *) const noexcept final override {
    return 0;
  }

  simdutf_warn_unused size_t convert_latin1_to_utf32(
      const char *, size_t, char32_t *) const noexcept final override {
    return 0;
  }

  simdutf_warn_unused size_t convert_utf8_to_latin1(
      const char *, size_t, char *) const noexcept final override {
    return 0;
  }

  simdutf_warn_unused result convert_utf8_to_latin1_with_errors(
      const char *, size_t, char *) const noexcept final override {
    return result(error_code::OTHER, 0);
  }

  simdutf_warn_unused size_t convert_valid_utf8_to_latin1(
      const char *, size_t, char *) const noexcept final override {
    return 0;
  }

  simdutf_warn_unused size_t convert_utf8_to_utf16le(
      const char *, size_t, char16_t *) const noexcept final override {
    return 0;
  }

  simdutf_warn_unused size_t convert_utf8_to_utf16be(
      const char *, size_t, char16_t *) const noexcept final override {
    return 0;
  }

  simdutf_warn_unused result convert_utf8_to_utf16le_with_errors(
      const char *, size_t, char16_t *) const noexcept final override {
    return result(error_code::OTHER, 0);
  }

  simdutf_warn_unused result convert_utf8_to_utf16be_with_errors(
      const char *, size_t, char16_t *) const noexcept final override {
    return result(error_code::OTHER, 0);
  }

  simdutf_warn_unused size_t convert_valid_utf8_to_utf16le(
      const char *, size_t, char16_t *) const noexcept final override {
    return 0;
  }

  simdutf_warn_unused size_t convert_valid_utf8_to_utf16be(
      const char *, size_t, char16_t *) const noexcept final override {
    return 0;
  }

  simdutf_warn_unused size_t convert_utf8_to_utf32(
      const char *, size_t, char32_t *) const noexcept final override {
    return 0;
  }

  simdutf_warn_unused result convert_utf8_to_utf32_with_errors(
      const char *, size_t, char32_t *) const noexcept final override {
    return result(error_code::OTHER, 0);
  }

  simdutf_warn_unused size_t convert_valid_utf8_to_utf32(
      const char *, size_t, char32_t *) const noexcept final override {
    return 0;
  }

  simdutf_warn_unused size_t convert_utf16le_to_latin1(
      const char16_t *, size_t, char *) const noexcept final override {
    return 0;
  }

  simdutf_warn_unused size_t convert_utf16be_to_latin1(
      const char16_t *, size_t, char *) const noexcept final override {
    return 0;
  }

  simdutf_warn_unused result convert_utf16le_to_latin1_with_errors(
      const char16_t *, size_t, char *) const noexcept final override {
    return result(error_code::OTHER, 0);
  }

  simdutf_warn_unused result convert_utf16be_to_latin1_with_errors(
      const char16_t *, size_t, char *) const noexcept final override {
    return result(error_code::OTHER, 0);
  }

  simdutf_warn_unused size_t convert_valid_utf16le_to_latin1(
      const char16_t *, size_t, char *) const noexcept final override {
    return 0;
  }

  simdutf_warn_unused size_t convert_valid_utf16be_to_latin1(
      const char16_t *, size_t, char *) const noexcept final override {
    return 0;
  }

  simdutf_warn_unused size_t convert_utf16le_to_utf8(
      const char16_t *, size_t, char *) const noexcept final override {
    return 0;
  }

  simdutf_warn_unused size_t convert_utf16be_to_utf8(
      const char16_t *, size_t, char *) const noexcept final override {
    return 0;
  }

  simdutf_warn_unused result convert_utf16le_to_utf8_with_errors(
      const char16_t *, size_t, char *) const noexcept final override {
    return result(error_code::OTHER, 0);
  }

  simdutf_warn_unused result convert_utf16be_to_utf8_with_errors(
      const char16_t *, size_t, char *) const noexcept final override {
    return result(error_code::OTHER, 0);
  }

  simdutf_warn_unused size_t convert_valid_utf16le_to_utf8(
      const char16_t *, size_t, char *) const noexcept final override {
    return 0;
  }

  simdutf_warn_unused size_t convert_valid_utf16be_to_utf8(
      const char16_t *, size_t, char *) const noexcept final override {
    return 0;
  }

  simdutf_warn_unused size_t convert_utf32_to_latin1(
      const char32_t *, size_t, char *) const noexcept final override {
    return 0;
  }

  simdutf_warn_unused result convert_utf32_to_latin1_with_errors(
      const char32_t *, size_t, char *) const noexcept final override {
    return result(error_code::OTHER, 0);
  }

  simdutf_warn_unused size_t convert_valid_utf32_to_latin1(
      const char32_t *, size_t, char *) const noexcept final override {
    return 0;
  }

  simdutf_warn_unused size_t convert_utf32_to_utf8(
      const char32_t *, size_t, char *) const noexcept final override {
    return 0;
  }

  simdutf_warn_unused result convert_utf32_to_utf8_with_errors(
      const char32_t *, size_t, char *) const noexcept final override {
    return result(error_code::OTHER, 0);
  }

  simdutf_warn_unused size_t convert_valid_utf32_to_utf8(
      const char32_t *, size_t, char *) const noexcept final override {
    return 0;
  }

  simdutf_warn_unused size_t convert_utf32_to_utf16le(
      const char32_t *, size_t, char16_t *) const noexcept final override {
    return 0;
  }

  simdutf_warn_unused size_t convert_utf32_to_utf16be(
      const char32_t *, size_t, char16_t *) const noexcept final override {
    return 0;
  }

  simdutf_warn_unused result convert_utf32_to_utf16le_with_errors(
      const char32_t *, size_t, char16_t *) const noexcept final override {
    return result(error_code::OTHER, 0);
  }

  simdutf_warn_unused result convert_utf32_to_utf16be_with_errors(
      const char32_t *, size_t, char16_t *) const noexcept final override {
    return result(error_code::OTHER, 0);
  }

  simdutf_warn_unused size_t convert_valid_utf32_to_utf16le(
      const char32_t *, size_t, char16_t *) const noexcept final override {
    return 0;
  }

  simdutf_warn_unused size_t convert_valid_utf32_to_utf16be(
      const char32_t *, size_t, char16_t *) const noexcept final override {
    return 0;
  }

  simdutf_warn_unused size_t convert_utf16le_to_utf32(
      const char16_t *, size_t, char32_t *) const noexcept final override {
    return 0;
  }

  simdutf_warn_unused size_t convert_utf16be_to_utf32(
      const char16_t *, size_t, char32_t *) const noexcept final override {
    return 0;
  }

  simdutf_warn_unused result convert_utf16le_to_utf32_with_errors(
      const char16_t *, size_t, char32_t *) const noexcept final override {
    return result(error_code::OTHER, 0);
  }

  simdutf_warn_unused result convert_utf16be_to_utf32_with_errors(
      const char16_t *, size_t, char32_t *) const noexcept final override {
    return result(error_code::OTHER, 0);
  }

  simdutf_warn_unused size_t convert_valid_utf16le_to_utf32(
      const char16_t *, size_t, char32_t *) const noexcept final override {
    return 0;
  }

  simdutf_warn_unused size_t convert_valid_utf16be_to_utf32(
      const char16_t *, size_t, char32_t *) const noexcept final override {
    return 0;
  }

  void change_endianness_utf16(const char16_t *, size_t,
                               char16_t *) const noexcept final override {}

  simdutf_warn_unused size_t
  count_utf16le(const char16_t *, size_t) const noexcept final override {
    return 0;
  }

  simdutf_warn_unused size_t
  count_utf16be(const char16_t *, size_t) const noexcept final override {
    return 0;
  }

  simdutf_warn_unused size_t count_utf8(const char *,
                                        size_t) const noexcept final override {
    return 0;
  }

  simdutf_warn_unused size_t
  latin1_length_from_utf8(const char *, size_t) const noexcept override {
    return 0;
  }

  simdutf_warn_unused size_t
  latin1_length_from_utf16(size_t) const noexcept override {
    return 0;
  }

  simdutf_warn_unused size_t
  latin1_length_from_utf32(size_t) const noexcept override {
    return 0;
  }
  simdutf_warn_unused size_t
  utf8_length_from_latin1(const char *, size_t) const noexcept override {
    return 0;
  }

  simdutf_warn_unused size_t
  utf8_length_from_utf16le(const char16_t *, size_t) const noexcept override {
    return 0;
  }

  simdutf_warn_unused size_t
  utf8_length_from_utf16be(const char16_t *, size_t) const noexcept override {
    return 0;
  }

  simdutf_warn_unused size_t
  utf32_length_from_utf16le(const char16_t *, size_t) const noexcept override {
    return 0;
  }

  simdutf_warn_unused size_t
  utf32_length_from_utf16be(const char16_t *, size_t) const noexcept override {
    return 0;
  }

  simdutf_warn_unused size_t
  utf32_length_from_latin1(size_t) const noexcept override {
    return 0;
  }

  simdutf_warn_unused size_t
  utf16_length_from_utf8(const char *, size_t) const noexcept override {
    return 0;
  }
  simdutf_warn_unused size_t
  utf16_length_from_latin1(size_t) const noexcept override {
    return 0;
  }
  simdutf_warn_unused size_t
  utf8_length_from_utf32(const char32_t *, size_t) const noexcept override {
    return 0;
  }

  simdutf_warn_unused size_t
  utf16_length_from_utf32(const char32_t *, size_t) const noexcept override {
    return 0;
  }

  simdutf_warn_unused size_t
  utf32_length_from_utf8(const char *, size_t) const noexcept override {
    return 0;
  }

  simdutf_warn_unused size_t maximal_binary_length_from_base64(
      const char *, size_t) const noexcept override {
    return 0;
  }

  simdutf_warn_unused result
  base64_to_binary(const char *, size_t, char *, base64_options,
                   last_chunk_handling_options) const noexcept override {
    return result(error_code::OTHER, 0);
  }

  simdutf_warn_unused full_result base64_to_binary_details(
      const char *, size_t, char *, base64_options,
      last_chunk_handling_options) const noexcept override {
    return full_result(error_code::OTHER, 0, 0);
  }

  simdutf_warn_unused size_t maximal_binary_length_from_base64(
      const char16_t *, size_t) const noexcept override {
    return 0;
  }

  simdutf_warn_unused result
  base64_to_binary(const char16_t *, size_t, char *, base64_options,
                   last_chunk_handling_options) const noexcept override {
    return result(error_code::OTHER, 0);
  }

  simdutf_warn_unused full_result base64_to_binary_details(
      const char16_t *, size_t, char *, base64_options,
      last_chunk_handling_options) const noexcept override {
    return full_result(error_code::OTHER, 0, 0);
  }

  simdutf_warn_unused size_t
  base64_length_from_binary(size_t, base64_options) const noexcept override {
    return 0;
  }

  size_t binary_to_base64(const char *, size_t, char *,
                          base64_options) const noexcept override {
    return 0;
  }

  unsupported_implementation()
      : implementation("unsupported",
                       "Unsupported CPU (no detected SIMD instructions)", 0) {}
};

const unsupported_implementation *get_unsupported_singleton() {
  static const unsupported_implementation unsupported_singleton{};
  return &unsupported_singleton;
}
static_assert(std::is_trivially_destructible<unsupported_implementation>::value,
              "unsupported_singleton should be trivially destructible");

size_t available_implementation_list::size() const noexcept {
  return internal::get_available_implementation_pointers().size();
}
const implementation *const *
available_implementation_list::begin() const noexcept {
  return internal::get_available_implementation_pointers().begin();
}
const implementation *const *
available_implementation_list::end() const noexcept {
  return internal::get_available_implementation_pointers().end();
}
const implementation *
available_implementation_list::detect_best_supported() const noexcept {
  // They are prelisted in priority order, so we just go down the list
  uint32_t supported_instruction_sets =
      internal::detect_supported_architectures();
  for (const implementation *impl :
       internal::get_available_implementation_pointers()) {
    uint32_t required_instruction_sets = impl->required_instruction_sets();
    if ((supported_instruction_sets & required_instruction_sets) ==
        required_instruction_sets) {
      return impl;
    }
  }
  return get_unsupported_singleton(); // this should never happen?
}

const implementation *
detect_best_supported_implementation_on_first_use::set_best() const noexcept {
  SIMDUTF_PUSH_DISABLE_WARNINGS
  SIMDUTF_DISABLE_DEPRECATED_WARNING // Disable CRT_SECURE warning on MSVC:
                                     // manually verified this is safe
      char *force_implementation_name = getenv("SIMDUTF_FORCE_IMPLEMENTATION");
  SIMDUTF_POP_DISABLE_WARNINGS

  if (force_implementation_name) {
    auto force_implementation =
        get_available_implementations()[force_implementation_name];
    if (force_implementation) {
      return get_active_implementation() = force_implementation;
    } else {
      // Note: abort() and stderr usage within the library is forbidden.
      return get_active_implementation() = get_unsupported_singleton();
    }
  }
  return get_active_implementation() =
             get_available_implementations().detect_best_supported();
}

} // namespace internal

/**
 * The list of available implementations compiled into simdutf.
 */
SIMDUTF_DLLIMPORTEXPORT const internal::available_implementation_list &
get_available_implementations() {
  static const internal::available_implementation_list
      available_implementations{};
  return available_implementations;
}

/**
 * The active implementation.
 */
SIMDUTF_DLLIMPORTEXPORT internal::atomic_ptr<const implementation> &
get_active_implementation() {
#if SIMDUTF_SINGLE_IMPLEMENTATION
  // skip runtime detection
  static internal::atomic_ptr<const implementation> active_implementation{
      internal::get_single_implementation()};
  return active_implementation;
#else
  static const internal::detect_best_supported_implementation_on_first_use
      detect_best_supported_implementation_on_first_use_singleton;
  static internal::atomic_ptr<const implementation> active_implementation{
      &detect_best_supported_implementation_on_first_use_singleton};
  return active_implementation;
#endif
}

#if SIMDUTF_SINGLE_IMPLEMENTATION
const implementation *get_default_implementation() {
  return internal::get_single_implementation();
}
#else
internal::atomic_ptr<const implementation> &get_default_implementation() {
  return get_active_implementation();
}
#endif
#define SIMDUTF_GET_CURRENT_IMPLEMENTION

simdutf_warn_unused bool validate_utf8(const char *buf, size_t len) noexcept {
  return get_default_implementation()->validate_utf8(buf, len);
}
simdutf_warn_unused result validate_utf8_with_errors(const char *buf,
                                                     size_t len) noexcept {
  return get_default_implementation()->validate_utf8_with_errors(buf, len);
}
simdutf_warn_unused bool validate_ascii(const char *buf, size_t len) noexcept {
  return get_default_implementation()->validate_ascii(buf, len);
}
simdutf_warn_unused result validate_ascii_with_errors(const char *buf,
                                                      size_t len) noexcept {
  return get_default_implementation()->validate_ascii_with_errors(buf, len);
}
simdutf_warn_unused size_t convert_utf8_to_utf16(
    const char *input, size_t length, char16_t *utf16_output) noexcept {
#if SIMDUTF_IS_BIG_ENDIAN
  return convert_utf8_to_utf16be(input, length, utf16_output);
#else
  return convert_utf8_to_utf16le(input, length, utf16_output);
#endif
}
simdutf_warn_unused size_t convert_latin1_to_utf8(const char *buf, size_t len,
                                                  char *utf8_output) noexcept {
  return get_default_implementation()->convert_latin1_to_utf8(buf, len,
                                                              utf8_output);
}
simdutf_warn_unused size_t convert_latin1_to_utf16le(
    const char *buf, size_t len, char16_t *utf16_output) noexcept {
  return get_default_implementation()->convert_latin1_to_utf16le(buf, len,
                                                                 utf16_output);
}
simdutf_warn_unused size_t convert_latin1_to_utf16be(
    const char *buf, size_t len, char16_t *utf16_output) noexcept {
  return get_default_implementation()->convert_latin1_to_utf16be(buf, len,
                                                                 utf16_output);
}
simdutf_warn_unused size_t convert_latin1_to_utf32(
    const char *buf, size_t len, char32_t *latin1_output) noexcept {
  return get_default_implementation()->convert_latin1_to_utf32(buf, len,
                                                               latin1_output);
}
simdutf_warn_unused size_t convert_utf8_to_latin1(
    const char *buf, size_t len, char *latin1_output) noexcept {
  return get_default_implementation()->convert_utf8_to_latin1(buf, len,
                                                              latin1_output);
}
simdutf_warn_unused result convert_utf8_to_latin1_with_errors(
    const char *buf, size_t len, char *latin1_output) noexcept {
  return get_default_implementation()->convert_utf8_to_latin1_with_errors(
      buf, len, latin1_output);
}
simdutf_warn_unused size_t convert_valid_utf8_to_latin1(
    const char *buf, size_t len, char *latin1_output) noexcept {
  return get_default_implementation()->convert_valid_utf8_to_latin1(
      buf, len, latin1_output);
}
simdutf_warn_unused size_t convert_utf8_to_utf16le(
    const char *input, size_t length, char16_t *utf16_output) noexcept {
  return get_default_implementation()->convert_utf8_to_utf16le(input, length,
                                                               utf16_output);
}
simdutf_warn_unused size_t convert_utf8_to_utf16be(
    const char *input, size_t length, char16_t *utf16_output) noexcept {
  return get_default_implementation()->convert_utf8_to_utf16be(input, length,
                                                               utf16_output);
}
simdutf_warn_unused result convert_utf8_to_utf16_with_errors(
    const char *input, size_t length, char16_t *utf16_output) noexcept {
#if SIMDUTF_IS_BIG_ENDIAN
  return convert_utf8_to_utf16be_with_errors(input, length, utf16_output);
#else
  return convert_utf8_to_utf16le_with_errors(input, length, utf16_output);
#endif
}
simdutf_warn_unused result convert_utf8_to_utf16le_with_errors(
    const char *input, size_t length, char16_t *utf16_output) noexcept {
  return get_default_implementation()->convert_utf8_to_utf16le_with_errors(
      input, length, utf16_output);
}
simdutf_warn_unused result convert_utf8_to_utf16be_with_errors(
    const char *input, size_t length, char16_t *utf16_output) noexcept {
  return get_default_implementation()->convert_utf8_to_utf16be_with_errors(
      input, length, utf16_output);
}
simdutf_warn_unused size_t convert_utf8_to_utf32(
    const char *input, size_t length, char32_t *utf32_output) noexcept {
  return get_default_implementation()->convert_utf8_to_utf32(input, length,
                                                             utf32_output);
}
simdutf_warn_unused result convert_utf8_to_utf32_with_errors(
    const char *input, size_t length, char32_t *utf32_output) noexcept {
  return get_default_implementation()->convert_utf8_to_utf32_with_errors(
      input, length, utf32_output);
}
simdutf_warn_unused bool validate_utf16(const char16_t *buf,
                                        size_t len) noexcept {
#if SIMDUTF_IS_BIG_ENDIAN
  return validate_utf16be(buf, len);
#else
  return validate_utf16le(buf, len);
#endif
}
simdutf_warn_unused bool validate_utf16le(const char16_t *buf,
                                          size_t len) noexcept {
  return get_default_implementation()->validate_utf16le(buf, len);
}
simdutf_warn_unused bool validate_utf16be(const char16_t *buf,
                                          size_t len) noexcept {
  return get_default_implementation()->validate_utf16be(buf, len);
}
simdutf_warn_unused result validate_utf16_with_errors(const char16_t *buf,
                                                      size_t len) noexcept {
#if SIMDUTF_IS_BIG_ENDIAN
  return validate_utf16be_with_errors(buf, len);
#else
  return validate_utf16le_with_errors(buf, len);
#endif
}
simdutf_warn_unused result validate_utf16le_with_errors(const char16_t *buf,
                                                        size_t len) noexcept {
  return get_default_implementation()->validate_utf16le_with_errors(buf, len);
}
simdutf_warn_unused result validate_utf16be_with_errors(const char16_t *buf,
                                                        size_t len) noexcept {
  return get_default_implementation()->validate_utf16be_with_errors(buf, len);
}
simdutf_warn_unused bool validate_utf32(const char32_t *buf,
                                        size_t len) noexcept {
  return get_default_implementation()->validate_utf32(buf, len);
}
simdutf_warn_unused result validate_utf32_with_errors(const char32_t *buf,
                                                      size_t len) noexcept {
  return get_default_implementation()->validate_utf32_with_errors(buf, len);
}
simdutf_warn_unused size_t convert_valid_utf8_to_utf16(
    const char *input, size_t length, char16_t *utf16_buffer) noexcept {
#if SIMDUTF_IS_BIG_ENDIAN
  return convert_valid_utf8_to_utf16be(input, length, utf16_buffer);
#else
  return convert_valid_utf8_to_utf16le(input, length, utf16_buffer);
#endif
}
simdutf_warn_unused size_t convert_valid_utf8_to_utf16le(
    const char *input, size_t length, char16_t *utf16_buffer) noexcept {
  return get_default_implementation()->convert_valid_utf8_to_utf16le(
      input, length, utf16_buffer);
}
simdutf_warn_unused size_t convert_valid_utf8_to_utf16be(
    const char *input, size_t length, char16_t *utf16_buffer) noexcept {
  return get_default_implementation()->convert_valid_utf8_to_utf16be(
      input, length, utf16_buffer);
}
simdutf_warn_unused size_t convert_valid_utf8_to_utf32(
    const char *input, size_t length, char32_t *utf32_buffer) noexcept {
  return get_default_implementation()->convert_valid_utf8_to_utf32(
      input, length, utf32_buffer);
}
simdutf_warn_unused size_t convert_utf16_to_utf8(const char16_t *buf,
                                                 size_t len,
                                                 char *utf8_buffer) noexcept {
#if SIMDUTF_IS_BIG_ENDIAN
  return convert_utf16be_to_utf8(buf, len, utf8_buffer);
#else
  return convert_utf16le_to_utf8(buf, len, utf8_buffer);
#endif
}
simdutf_warn_unused size_t convert_utf16_to_latin1(
    const char16_t *buf, size_t len, char *latin1_buffer) noexcept {
#if SIMDUTF_IS_BIG_ENDIAN
  return convert_utf16be_to_latin1(buf, len, latin1_buffer);
#else
  return convert_utf16le_to_latin1(buf, len, latin1_buffer);
#endif
}
simdutf_warn_unused size_t convert_latin1_to_utf16(
    const char *buf, size_t len, char16_t *utf16_output) noexcept {
#if SIMDUTF_IS_BIG_ENDIAN
  return convert_latin1_to_utf16be(buf, len, utf16_output);
#else
  return convert_latin1_to_utf16le(buf, len, utf16_output);
#endif
}
simdutf_warn_unused size_t convert_utf16be_to_latin1(
    const char16_t *buf, size_t len, char *latin1_buffer) noexcept {
  return get_default_implementation()->convert_utf16be_to_latin1(buf, len,
                                                                 latin1_buffer);
}
simdutf_warn_unused size_t convert_utf16le_to_latin1(
    const char16_t *buf, size_t len, char *latin1_buffer) noexcept {
  return get_default_implementation()->convert_utf16le_to_latin1(buf, len,
                                                                 latin1_buffer);
}
simdutf_warn_unused size_t convert_valid_utf16be_to_latin1(
    const char16_t *buf, size_t len, char *latin1_buffer) noexcept {
  return get_default_implementation()->convert_valid_utf16be_to_latin1(
      buf, len, latin1_buffer);
}
simdutf_warn_unused size_t convert_valid_utf16le_to_latin1(
    const char16_t *buf, size_t len, char *latin1_buffer) noexcept {
  return get_default_implementation()->convert_valid_utf16le_to_latin1(
      buf, len, latin1_buffer);
}
simdutf_warn_unused result convert_utf16le_to_latin1_with_errors(
    const char16_t *buf, size_t len, char *latin1_buffer) noexcept {
  return get_default_implementation()->convert_utf16le_to_latin1_with_errors(
      buf, len, latin1_buffer);
}
simdutf_warn_unused result convert_utf16be_to_latin1_with_errors(
    const char16_t *buf, size_t len, char *latin1_buffer) noexcept {
  return get_default_implementation()->convert_utf16be_to_latin1_with_errors(
      buf, len, latin1_buffer);
}
simdutf_warn_unused size_t convert_utf16le_to_utf8(const char16_t *buf,
                                                   size_t len,
                                                   char *utf8_buffer) noexcept {
  return get_default_implementation()->convert_utf16le_to_utf8(buf, len,
                                                               utf8_buffer);
}
simdutf_warn_unused size_t convert_utf16be_to_utf8(const char16_t *buf,
                                                   size_t len,
                                                   char *utf8_buffer) noexcept {
  return get_default_implementation()->convert_utf16be_to_utf8(buf, len,
                                                               utf8_buffer);
}
simdutf_warn_unused result convert_utf16_to_utf8_with_errors(
    const char16_t *buf, size_t len, char *utf8_buffer) noexcept {
#if SIMDUTF_IS_BIG_ENDIAN
  return convert_utf16be_to_utf8_with_errors(buf, len, utf8_buffer);
#else
  return convert_utf16le_to_utf8_with_errors(buf, len, utf8_buffer);
#endif
}
simdutf_warn_unused result convert_utf16_to_latin1_with_errors(
    const char16_t *buf, size_t len, char *latin1_buffer) noexcept {
#if SIMDUTF_IS_BIG_ENDIAN
  return convert_utf16be_to_latin1_with_errors(buf, len, latin1_buffer);
#else
  return convert_utf16le_to_latin1_with_errors(buf, len, latin1_buffer);
#endif
}
simdutf_warn_unused result convert_utf16le_to_utf8_with_errors(
    const char16_t *buf, size_t len, char *utf8_buffer) noexcept {
  return get_default_implementation()->convert_utf16le_to_utf8_with_errors(
      buf, len, utf8_buffer);
}
simdutf_warn_unused result convert_utf16be_to_utf8_with_errors(
    const char16_t *buf, size_t len, char *utf8_buffer) noexcept {
  return get_default_implementation()->convert_utf16be_to_utf8_with_errors(
      buf, len, utf8_buffer);
}
simdutf_warn_unused size_t convert_valid_utf16_to_utf8(
    const char16_t *buf, size_t len, char *utf8_buffer) noexcept {
#if SIMDUTF_IS_BIG_ENDIAN
  return convert_valid_utf16be_to_utf8(buf, len, utf8_buffer);
#else
  return convert_valid_utf16le_to_utf8(buf, len, utf8_buffer);
#endif
}
simdutf_warn_unused size_t convert_valid_utf16_to_latin1(
    const char16_t *buf, size_t len, char *latin1_buffer) noexcept {
#if SIMDUTF_IS_BIG_ENDIAN
  return convert_valid_utf16be_to_latin1(buf, len, latin1_buffer);
#else
  return convert_valid_utf16le_to_latin1(buf, len, latin1_buffer);
#endif
}
simdutf_warn_unused size_t convert_valid_utf16le_to_utf8(
    const char16_t *buf, size_t len, char *utf8_buffer) noexcept {
  return get_default_implementation()->convert_valid_utf16le_to_utf8(
      buf, len, utf8_buffer);
}
simdutf_warn_unused size_t convert_valid_utf16be_to_utf8(
    const char16_t *buf, size_t len, char *utf8_buffer) noexcept {
  return get_default_implementation()->convert_valid_utf16be_to_utf8(
      buf, len, utf8_buffer);
}
simdutf_warn_unused size_t convert_utf32_to_utf8(const char32_t *buf,
                                                 size_t len,
                                                 char *utf8_buffer) noexcept {
  return get_default_implementation()->convert_utf32_to_utf8(buf, len,
                                                             utf8_buffer);
}
simdutf_warn_unused result convert_utf32_to_utf8_with_errors(
    const char32_t *buf, size_t len, char *utf8_buffer) noexcept {
  return get_default_implementation()->convert_utf32_to_utf8_with_errors(
      buf, len, utf8_buffer);
}
simdutf_warn_unused size_t convert_valid_utf32_to_utf8(
    const char32_t *buf, size_t len, char *utf8_buffer) noexcept {
  return get_default_implementation()->convert_valid_utf32_to_utf8(buf, len,
                                                                   utf8_buffer);
}
simdutf_warn_unused size_t convert_utf32_to_utf16(
    const char32_t *buf, size_t len, char16_t *utf16_buffer) noexcept {
#if SIMDUTF_IS_BIG_ENDIAN
  return convert_utf32_to_utf16be(buf, len, utf16_buffer);
#else
  return convert_utf32_to_utf16le(buf, len, utf16_buffer);
#endif
}
simdutf_warn_unused size_t convert_utf32_to_latin1(
    const char32_t *input, size_t length, char *latin1_output) noexcept {
  return get_default_implementation()->convert_utf32_to_latin1(input, length,
                                                               latin1_output);
}
simdutf_warn_unused size_t convert_utf32_to_utf16le(
    const char32_t *buf, size_t len, char16_t *utf16_buffer) noexcept {
  return get_default_implementation()->convert_utf32_to_utf16le(buf, len,
                                                                utf16_buffer);
}
simdutf_warn_unused size_t convert_utf32_to_utf16be(
    const char32_t *buf, size_t len, char16_t *utf16_buffer) noexcept {
  return get_default_implementation()->convert_utf32_to_utf16be(buf, len,
                                                                utf16_buffer);
}
simdutf_warn_unused result convert_utf32_to_utf16_with_errors(
    const char32_t *buf, size_t len, char16_t *utf16_buffer) noexcept {
#if SIMDUTF_IS_BIG_ENDIAN
  return convert_utf32_to_utf16be_with_errors(buf, len, utf16_buffer);
#else
  return convert_utf32_to_utf16le_with_errors(buf, len, utf16_buffer);
#endif
}
simdutf_warn_unused result convert_utf32_to_utf16le_with_errors(
    const char32_t *buf, size_t len, char16_t *utf16_buffer) noexcept {
  return get_default_implementation()->convert_utf32_to_utf16le_with_errors(
      buf, len, utf16_buffer);
}
simdutf_warn_unused result convert_utf32_to_utf16be_with_errors(
    const char32_t *buf, size_t len, char16_t *utf16_buffer) noexcept {
  return get_default_implementation()->convert_utf32_to_utf16be_with_errors(
      buf, len, utf16_buffer);
}
simdutf_warn_unused size_t convert_valid_utf32_to_utf16(
    const char32_t *buf, size_t len, char16_t *utf16_buffer) noexcept {
#if SIMDUTF_IS_BIG_ENDIAN
  return convert_valid_utf32_to_utf16be(buf, len, utf16_buffer);
#else
  return convert_valid_utf32_to_utf16le(buf, len, utf16_buffer);
#endif
}
simdutf_warn_unused size_t convert_valid_utf32_to_utf16le(
    const char32_t *buf, size_t len, char16_t *utf16_buffer) noexcept {
  return get_default_implementation()->convert_valid_utf32_to_utf16le(
      buf, len, utf16_buffer);
}
simdutf_warn_unused size_t convert_valid_utf32_to_utf16be(
    const char32_t *buf, size_t len, char16_t *utf16_buffer) noexcept {
  return get_default_implementation()->convert_valid_utf32_to_utf16be(
      buf, len, utf16_buffer);
}
simdutf_warn_unused size_t convert_utf16_to_utf32(
    const char16_t *buf, size_t len, char32_t *utf32_buffer) noexcept {
#if SIMDUTF_IS_BIG_ENDIAN
  return convert_utf16be_to_utf32(buf, len, utf32_buffer);
#else
  return convert_utf16le_to_utf32(buf, len, utf32_buffer);
#endif
}
simdutf_warn_unused size_t convert_utf16le_to_utf32(
    const char16_t *buf, size_t len, char32_t *utf32_buffer) noexcept {
  return get_default_implementation()->convert_utf16le_to_utf32(buf, len,
                                                                utf32_buffer);
}
simdutf_warn_unused size_t convert_utf16be_to_utf32(
    const char16_t *buf, size_t len, char32_t *utf32_buffer) noexcept {
  return get_default_implementation()->convert_utf16be_to_utf32(buf, len,
                                                                utf32_buffer);
}
simdutf_warn_unused result convert_utf16_to_utf32_with_errors(
    const char16_t *buf, size_t len, char32_t *utf32_buffer) noexcept {
#if SIMDUTF_IS_BIG_ENDIAN
  return convert_utf16be_to_utf32_with_errors(buf, len, utf32_buffer);
#else
  return convert_utf16le_to_utf32_with_errors(buf, len, utf32_buffer);
#endif
}
simdutf_warn_unused result convert_utf16le_to_utf32_with_errors(
    const char16_t *buf, size_t len, char32_t *utf32_buffer) noexcept {
  return get_default_implementation()->convert_utf16le_to_utf32_with_errors(
      buf, len, utf32_buffer);
}
simdutf_warn_unused result convert_utf16be_to_utf32_with_errors(
    const char16_t *buf, size_t len, char32_t *utf32_buffer) noexcept {
  return get_default_implementation()->convert_utf16be_to_utf32_with_errors(
      buf, len, utf32_buffer);
}
simdutf_warn_unused size_t convert_valid_utf16_to_utf32(
    const char16_t *buf, size_t len, char32_t *utf32_buffer) noexcept {
#if SIMDUTF_IS_BIG_ENDIAN
  return convert_valid_utf16be_to_utf32(buf, len, utf32_buffer);
#else
  return convert_valid_utf16le_to_utf32(buf, len, utf32_buffer);
#endif
}
simdutf_warn_unused size_t convert_valid_utf16le_to_utf32(
    const char16_t *buf, size_t len, char32_t *utf32_buffer) noexcept {
  return get_default_implementation()->convert_valid_utf16le_to_utf32(
      buf, len, utf32_buffer);
}
simdutf_warn_unused size_t convert_valid_utf16be_to_utf32(
    const char16_t *buf, size_t len, char32_t *utf32_buffer) noexcept {
  return get_default_implementation()->convert_valid_utf16be_to_utf32(
      buf, len, utf32_buffer);
}
void change_endianness_utf16(const char16_t *input, size_t length,
                             char16_t *output) noexcept {
  get_default_implementation()->change_endianness_utf16(input, length, output);
}
simdutf_warn_unused size_t count_utf16(const char16_t *input,
                                       size_t length) noexcept {
#if SIMDUTF_IS_BIG_ENDIAN
  return count_utf16be(input, length);
#else
  return count_utf16le(input, length);
#endif
}
simdutf_warn_unused size_t count_utf16le(const char16_t *input,
                                         size_t length) noexcept {
  return get_default_implementation()->count_utf16le(input, length);
}
simdutf_warn_unused size_t count_utf16be(const char16_t *input,
                                         size_t length) noexcept {
  return get_default_implementation()->count_utf16be(input, length);
}
simdutf_warn_unused size_t count_utf8(const char *input,
                                      size_t length) noexcept {
  return get_default_implementation()->count_utf8(input, length);
}
simdutf_warn_unused size_t latin1_length_from_utf8(const char *buf,
                                                   size_t len) noexcept {
  return get_default_implementation()->latin1_length_from_utf8(buf, len);
}
simdutf_warn_unused size_t latin1_length_from_utf16(size_t len) noexcept {
  return get_default_implementation()->latin1_length_from_utf16(len);
}
simdutf_warn_unused size_t latin1_length_from_utf32(size_t len) noexcept {
  return get_default_implementation()->latin1_length_from_utf32(len);
}
simdutf_warn_unused size_t utf8_length_from_latin1(const char *buf,
                                                   size_t len) noexcept {
  return get_default_implementation()->utf8_length_from_latin1(buf, len);
}
simdutf_warn_unused size_t utf8_length_from_utf16(const char16_t *input,
                                                  size_t length) noexcept {
#if SIMDUTF_IS_BIG_ENDIAN
  return utf8_length_from_utf16be(input, length);
#else
  return utf8_length_from_utf16le(input, length);
#endif
}
simdutf_warn_unused size_t utf8_length_from_utf16le(const char16_t *input,
                                                    size_t length) noexcept {
  return get_default_implementation()->utf8_length_from_utf16le(input, length);
}
simdutf_warn_unused size_t utf8_length_from_utf16be(const char16_t *input,
                                                    size_t length) noexcept {
  return get_default_implementation()->utf8_length_from_utf16be(input, length);
}
simdutf_warn_unused size_t utf32_length_from_utf16(const char16_t *input,
                                                   size_t length) noexcept {
#if SIMDUTF_IS_BIG_ENDIAN
  return utf32_length_from_utf16be(input, length);
#else
  return utf32_length_from_utf16le(input, length);
#endif
}
simdutf_warn_unused size_t utf32_length_from_utf16le(const char16_t *input,
                                                     size_t length) noexcept {
  return get_default_implementation()->utf32_length_from_utf16le(input, length);
}
simdutf_warn_unused size_t utf32_length_from_utf16be(const char16_t *input,
                                                     size_t length) noexcept {
  return get_default_implementation()->utf32_length_from_utf16be(input, length);
}
simdutf_warn_unused size_t utf16_length_from_utf8(const char *input,
                                                  size_t length) noexcept {
  return get_default_implementation()->utf16_length_from_utf8(input, length);
}
simdutf_warn_unused size_t utf16_length_from_latin1(size_t length) noexcept {
  return get_default_implementation()->utf16_length_from_latin1(length);
}
simdutf_warn_unused size_t utf8_length_from_utf32(const char32_t *input,
                                                  size_t length) noexcept {
  return get_default_implementation()->utf8_length_from_utf32(input, length);
}
simdutf_warn_unused size_t utf16_length_from_utf32(const char32_t *input,
                                                   size_t length) noexcept {
  return get_default_implementation()->utf16_length_from_utf32(input, length);
}
simdutf_warn_unused size_t utf32_length_from_utf8(const char *input,
                                                  size_t length) noexcept {
  return get_default_implementation()->utf32_length_from_utf8(input, length);
}

simdutf_warn_unused size_t
maximal_binary_length_from_base64(const char *input, size_t length) noexcept {
  return get_default_implementation()->maximal_binary_length_from_base64(
      input, length);
}

simdutf_warn_unused result base64_to_binary(
    const char *input, size_t length, char *output, base64_options options,
    last_chunk_handling_options last_chunk_handling_options) noexcept {
  return get_default_implementation()->base64_to_binary(
      input, length, output, options, last_chunk_handling_options);
}

simdutf_warn_unused size_t maximal_binary_length_from_base64(
    const char16_t *input, size_t length) noexcept {
  return get_default_implementation()->maximal_binary_length_from_base64(
      input, length);
}

simdutf_warn_unused result base64_to_binary(
    const char16_t *input, size_t length, char *output, base64_options options,
    last_chunk_handling_options last_chunk_handling_options) noexcept {
  return get_default_implementation()->base64_to_binary(
      input, length, output, options, last_chunk_handling_options);
}

template <typename chartype>
simdutf_warn_unused result base64_to_binary_safe_impl(
    const chartype *input, size_t length, char *output, size_t &outlen,
    base64_options options,
    last_chunk_handling_options last_chunk_handling_options) noexcept {
  static_assert(std::is_same<chartype, char>::value ||
                    std::is_same<chartype, char16_t>::value,
                "Only char and char16_t are supported.");
  // The implementation could be nicer, but we expect that most times, the user
  // will provide us with a buffer that is large enough.
  size_t max_length = maximal_binary_length_from_base64(input, length);
  if (outlen >= max_length) {
    // fast path
    full_result r = get_default_implementation()->base64_to_binary_details(
        input, length, output, options, last_chunk_handling_options);
    if (r.error != error_code::INVALID_BASE64_CHARACTER &&
        r.error != error_code::BASE64_EXTRA_BITS) {
      outlen = r.output_count;
      if (last_chunk_handling_options == stop_before_partial) {
        if ((r.output_count % 3) != 0) {
          bool empty_trail = true;
          for (size_t i = r.input_count; i < length; i++) {
            if (!scalar::base64::is_ascii_white_space_or_padding(input[i])) {
              empty_trail = false;
              break;
            }
          }
          if (empty_trail) {
            r.input_count = length;
          }
        }
        return {r.error, r.input_count};
      }
      return {r.error, length};
    }
    return r;
  }
  // The output buffer is maybe too small. We will decode a truncated version of
  // the input.
  size_t outlen3 = outlen / 3 * 3; // round down to multiple of 3
  size_t safe_input = base64_length_from_binary(outlen3, options);
  full_result r = get_default_implementation()->base64_to_binary_details(
      input, safe_input, output, options, loose);
  if (r.error == error_code::INVALID_BASE64_CHARACTER) {
    return r;
  }
  size_t offset =
      (r.error == error_code::BASE64_INPUT_REMAINDER)
          ? 1
          : ((r.output_count % 3) == 0 ? 0 : (r.output_count % 3) + 1);
  size_t output_index = r.output_count - (r.output_count % 3);
  size_t input_index = safe_input;
  // offset is a value that is no larger than 3. We backtrack
  // by up to offset characters + an undetermined number of
  // white space characters. It is expected that the next loop
  // runs at most 3 times + the number of white space characters
  // in between them, so we are not worried about performance.
  while (offset > 0 && input_index > 0) {
    chartype c = input[--input_index];
    if (scalar::base64::is_ascii_white_space(c)) {
      // skipping
    } else {
      offset--;
    }
  }
  size_t remaining_out = outlen - output_index;
  const chartype *tail_input = input + input_index;
  size_t tail_length = length - input_index;
  while (tail_length > 0 &&
         scalar::base64::is_ascii_white_space(tail_input[tail_length - 1])) {
    tail_length--;
  }
  size_t padding_characts = 0;
  if (tail_length > 0 && tail_input[tail_length - 1] == '=') {
    tail_length--;
    padding_characts++;
    while (tail_length > 0 &&
           scalar::base64::is_ascii_white_space(tail_input[tail_length - 1])) {
      tail_length--;
    }
    if (tail_length > 0 && tail_input[tail_length - 1] == '=') {
      tail_length--;
      padding_characts++;
    }
  }
  // this will advance tail_input and tail_length
  result rr = scalar::base64::base64_tail_decode_safe(
      output + output_index, remaining_out, tail_input, tail_length,
      padding_characts, options, last_chunk_handling_options);
  outlen = output_index + remaining_out;
  if (last_chunk_handling_options != stop_before_partial &&
      rr.error == error_code::SUCCESS && padding_characts > 0) {
    // additional checks
    if ((outlen % 3 == 0) || ((outlen % 3) + 1 + padding_characts != 4)) {
      rr.error = error_code::INVALID_BASE64_CHARACTER;
    }
  }
  if (rr.error == error_code::SUCCESS &&
      last_chunk_handling_options == stop_before_partial) {
    if (tail_input > input + input_index) {
      rr.count = tail_input - input;
    } else if (r.input_count > 0) {
      rr.count = r.input_count + rr.count;
    }
    return rr;
  }
  rr.count += input_index;
  return rr;
}

simdutf_warn_unused size_t convert_latin1_to_utf8_safe(
    const char *buf, size_t len, char *utf8_output, size_t utf8_len) noexcept {
  const auto start{utf8_output};

  while (true) {
    // convert_latin1_to_utf8 will never write more than input length * 2
    auto read_len = std::min(len, utf8_len >> 1);
    if (read_len <= 16) {
      break;
    }

    const auto write_len =
        simdutf::convert_latin1_to_utf8(buf, read_len, utf8_output);

    utf8_output += write_len;
    utf8_len -= write_len;
    buf += read_len;
    len -= read_len;
  }

  utf8_output +=
      scalar::latin1_to_utf8::convert_safe(buf, len, utf8_output, utf8_len);

  return utf8_output - start;
}

simdutf_warn_unused result base64_to_binary_safe(
    const char *input, size_t length, char *output, size_t &outlen,
    base64_options options,
    last_chunk_handling_options last_chunk_handling_options) noexcept {
  return base64_to_binary_safe_impl<char>(input, length, output, outlen,
                                          options, last_chunk_handling_options);
}
simdutf_warn_unused result base64_to_binary_safe(
    const char16_t *input, size_t length, char *output, size_t &outlen,
    base64_options options,
    last_chunk_handling_options last_chunk_handling_options) noexcept {
  return base64_to_binary_safe_impl<char16_t>(
      input, length, output, outlen, options, last_chunk_handling_options);
}

simdutf_warn_unused size_t
base64_length_from_binary(size_t length, base64_options options) noexcept {
  return get_default_implementation()->base64_length_from_binary(length,
                                                                 options);
}

size_t binary_to_base64(const char *input, size_t length, char *output,
                        base64_options options) noexcept {
  return get_default_implementation()->binary_to_base64(input, length, output,
                                                        options);
}

simdutf_warn_unused simdutf::encoding_type
autodetect_encoding(const char *buf, size_t length) noexcept {
  return get_default_implementation()->autodetect_encoding(buf, length);
}
simdutf_warn_unused int detect_encodings(const char *buf,
                                         size_t length) noexcept {
  return get_default_implementation()->detect_encodings(buf, length);
}
const implementation *builtin_implementation() {
  static const implementation *builtin_impl =
      get_available_implementations()[SIMDUTF_STRINGIFY(
          SIMDUTF_BUILTIN_IMPLEMENTATION)];
  return builtin_impl;
}

simdutf_warn_unused size_t trim_partial_utf8(const char *input, size_t length) {
  return scalar::utf8::trim_partial_utf8(input, length);
}

simdutf_warn_unused size_t trim_partial_utf16be(const char16_t *input,
                                                size_t length) {
  return scalar::utf16::trim_partial_utf16<BIG>(input, length);
}

simdutf_warn_unused size_t trim_partial_utf16le(const char16_t *input,
                                                size_t length) {
  return scalar::utf16::trim_partial_utf16<LITTLE>(input, length);
}

simdutf_warn_unused size_t trim_partial_utf16(const char16_t *input,
                                              size_t length) {
#if SIMDUTF_IS_BIG_ENDIAN
  return trim_partial_utf16be(input, length);
#else
  return trim_partial_utf16le(input, length);
#endif
}

} // namespace simdutf