/**
 * Author......: See docs/credits.txt
 * License.....: MIT
 */

#include "inc_vendor.h"
#include "inc_types.h"
#include "inc_platform.h"
#include "inc_common.h"
#include "inc_rp.h"

#ifndef MAYBE_UNUSED
#define MAYBE_UNUSED
#endif

#ifdef REAL_SHM
#define COPY_PW(x)               \
  LOCAL_VK pw_t s_pws[64];       \
  s_pws[get_local_id (0)] = (x);
#else
#define COPY_PW(x)               \
  pw_t pw = (x);
#endif

#ifdef REAL_SHM
#define PASTE_PW s_pws[get_local_id(0)];
#else
#define PASTE_PW pw;
#endif

CONSTANT_AS u8 s_lookup[128] =
{
  // 0-31: control characters (0)
  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  // 32: whitespace (1)
  1,
  // 33-47: punctuation (1)
  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
  // 48-57: digits (0)
  0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  // 58-64: punctuation (1)
  1, 1, 1, 1, 1, 1, 1,
  // 65-90: uppercase letters (0)
  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  // 91-96: punctuation (1)
  1, 1, 1, 1, 1, 1,
  // 97-122: lowercase letters (0)
  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  // 123-126: punctuation (1)
  1, 1, 1, 1,
  // 127: DEL (0)
  0
};

HC_INLINE bool is_l (u8 c)
{
  return (c >= 'a' && c <= 'z');
}

HC_INLINE bool is_u (u8 c)
{
  return (c >= 'A' && c <= 'Z');
}

HC_INLINE bool is_d (u8 c)
{
  return (c >= '0' && c <= '9');
}

HC_INLINE bool is_lh (u8 c)
{
  return (is_d (c) || (c >= 'a' && c <= 'f'));
}

HC_INLINE bool is_uh (u8 c)
{
  return (is_d (c) || (c >= 'A' && c <= 'F'));
}

HC_INLINE bool is_s (u8 c)
{
  return s_lookup[c] == 1;
}

DECLSPEC u32 generate_cmask (const u32 value)
{
  const u32 rmask =  ((value & 0x40404040u) >> 1u)
                  & ~((value & 0x80808080u) >> 2u);

  const u32 hmask = (value & 0x1f1f1f1fu) + 0x05050505u;
  const u32 lmask = (value & 0x1f1f1f1fu) + 0x1f1f1f1fu;

  return rmask & ~hmask & lmask;
}

DECLSPEC void append_four_byte (PRIVATE_AS const u32 *buf_src, const int off_src, PRIVATE_AS u32 *buf_dst, const int off_dst)
{
  const int sd  = off_src / 4;
  const int sm  = off_src & 3;
  const int sm8 = sm * 8;

  const int dd  = off_dst / 4;
  const int dm  = off_dst & 3;
  const int dm8 = dm * 8;

  u64 t64 = hl32_to_64_S (buf_src[sd + 1], buf_src[sd + 0]);

  t64 >>= sm8;
  t64  &= 0xffffffff;
  t64 <<= dm8;

  const u32 t0 = l32_from_64_S (t64);
  const u32 t1 = h32_from_64_S (t64);

  buf_dst[dd + 0] |= t0;
  buf_dst[dd + 1] |= t1;
}

DECLSPEC void append_three_byte (PRIVATE_AS const u32 *buf_src, const int off_src, PRIVATE_AS u32 *buf_dst, const int off_dst)
{
  const int sd  = off_src / 4;
  const int sm  = off_src & 3;
  const int sm8 = sm * 8;

  const int dd  = off_dst / 4;
  const int dm  = off_dst & 3;
  const int dm8 = dm * 8;

  u64 t64 = hl32_to_64_S (buf_src[sd + 1], buf_src[sd + 0]);

  t64 >>= sm8;
  t64  &= 0x00ffffff;
  t64 <<= dm8;

  const u32 t0 = l32_from_64_S (t64);
  const u32 t1 = h32_from_64_S (t64);

  buf_dst[dd + 0] |= t0;
  buf_dst[dd + 1] |= t1;
}

DECLSPEC void append_two_byte (PRIVATE_AS const u32 *buf_src, const int off_src, PRIVATE_AS u32 *buf_dst, const int off_dst)
{
  const int sd  = off_src / 4;
  const int sm  = off_src & 3;
  const int sm8 = sm * 8;

  const int dd  = off_dst / 4;
  const int dm  = off_dst & 3;
  const int dm8 = dm * 8;

  u64 t64 = hl32_to_64_S (buf_src[sd + 1], buf_src[sd + 0]);

  t64 >>= sm8;
  t64  &= 0x0000ffff;
  t64 <<= dm8;

  const u32 t0 = l32_from_64_S (t64);
  const u32 t1 = h32_from_64_S (t64);

  buf_dst[dd + 0] |= t0;
  buf_dst[dd + 1] |= t1;
}

DECLSPEC void append_one_byte (PRIVATE_AS const u32 *buf_src, const int off_src, PRIVATE_AS u32 *buf_dst, const int off_dst)
{
  const int sd  = off_src / 4;
  const int sm  = off_src & 3;
  const int sm8 = sm * 8;

  const int dd  = off_dst / 4;
  const int dm  = off_dst & 3;
  const int dm8 = dm * 8;

  u32 t = buf_src[sd];

  t >>= sm8;
  t  &= 0xff;
  t <<= dm8;

  buf_dst[dd] |= t;
}

DECLSPEC void append_block (PRIVATE_AS const u32 *buf_src, const int off_src, PRIVATE_AS u32 *buf_dst, const int off_dst, const int len)
{
  int i;

  for (i = 0; i < len - 3; i += 4)
  {
    append_four_byte (buf_src, off_src + i, buf_dst, off_dst + i);
  }

  const int left = len - i;

  switch (left)
  {
    case 3: append_three_byte (buf_src, off_src + i, buf_dst, off_dst + i); break;
    case 2: append_two_byte   (buf_src, off_src + i, buf_dst, off_dst + i); break;
    case 1: append_one_byte   (buf_src, off_src + i, buf_dst, off_dst + i); break;
  }
}

DECLSPEC void exchange_byte (PRIVATE_AS u32 *buf, const int off_src, const int off_dst)
{
  PRIVATE_AS u8 *ptr = (PRIVATE_AS u8 *) buf;

  const u8 tmp = ptr[off_src];

  ptr[off_src] = ptr[off_dst];
  ptr[off_dst] = tmp;

  /*
  something tells me we do this faster

  const int sd  = off_src / 4;
  const int sm  = off_src & 3;
  const int sm8 = sm * 8;

  const int dd  = off_dst / 4;
  const int dm  = off_dst & 3;
  const int dm8 = dm * 8;

  u32 ts = buf[sd];
  u32 td = buf[dd];

  ts >>= sm8;
  td >>= dm8;

  ts &= 0xff;
  td &= 0xff;

  const u32 x = ts ^ td;

  const u32 xs = x << sm8;
  const u32 xd = x << dm8;

  buf[sd] ^= xs;
  buf[dd] ^= xd;
  */
}

DECLSPEC int mangle_lrest (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u32 *buf, const int len)
{
  for (int i = 0, idx = 0; i < len; i += 4, idx += 1)
  {
    const u32 t = buf[idx];

    buf[idx] = t | generate_cmask (t);
  }

  return len;
}

DECLSPEC int mangle_lrest_ufirst (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u32 *buf, const int len)
{
  for (int i = 0, idx = 0; i < len; i += 4, idx += 1)
  {
    const u32 t = buf[idx];

    buf[idx] = t | generate_cmask (t);
  }

  const u32 t = buf[0];

  buf[0] = t & ~(0x00000020 & generate_cmask (t));

  return len;
}

DECLSPEC int mangle_urest (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u32 *buf, const int len)
{
  for (int i = 0, idx = 0; i < len; i += 4, idx += 1)
  {
    const u32 t = buf[idx];

    buf[idx] = t & ~(generate_cmask (t));
  }

  return len;
}

DECLSPEC int mangle_urest_lfirst (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u32 *buf, const int len)
{
  for (int i = 0, idx = 0; i < len; i += 4, idx += 1)
  {
    const u32 t = buf[idx];

    buf[idx] = t & ~(generate_cmask (t));
  }

  const u32 t = buf[0];

  buf[0] = t | (0x00000020 & generate_cmask (t));

  return len;
}

DECLSPEC int mangle_trest (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u32 *buf, const int len)
{
  for (int i = 0, idx = 0; i < len; i += 4, idx += 1)
  {
    const u32 t = buf[idx];

    buf[idx] = t ^ generate_cmask (t);
  }

  return len;
}

DECLSPEC int mangle_toggle_at (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u32 *buf, const int len)
{
  if (p0 >= len) return len;

  const u8 p0d = p0 / 4;
  const u8 p0m = p0 & 3;

  const u32 tmp = 0x20u << (p0m * 8);

  const u32 t = buf[p0d];

  buf[p0d] = t ^ (generate_cmask (t) & tmp);

  return len;
}

DECLSPEC int mangle_toggle_at_sep (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u32 *buf, const int len)
{
  if (len >= RP_PASSWORD_SIZE) return len;

  u8 occurence = 0;

  u32 rem = 0;

  for (int i = 0, idx = 0; i < len; i += 4, idx += 1)
  {
    const u32 t = buf[idx];

    buf[idx] = t | generate_cmask (t);

    u32 out = rem;

    rem = 0;

    if (((t >>  0) & 0xff) == p1) { if (occurence == p0) out = 0x0000ff00; occurence++; }
    if (((t >>  8) & 0xff) == p1) { if (occurence == p0) out = 0x00ff0000; occurence++; }
    if (((t >> 16) & 0xff) == p1) { if (occurence == p0) out = 0xff000000; occurence++; }
    if (((t >> 24) & 0xff) == p1) { if (occurence == p0) rem = 0x000000ff; occurence++; }

    buf[idx] = t ^ (generate_cmask (t) & out);
  }

  return len;
}

DECLSPEC int mangle_reverse (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u32 *buf, const int len)
{
  for (int l = 0; l < len / 2; l++)
  {
    const int r = len - 1 - l;

    exchange_byte (buf, l, r);
  }

  return len;
}

DECLSPEC int mangle_dupeword (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u32 *buf, const int len)
{
  const int out_len = len * 2;

  if (out_len >= RP_PASSWORD_SIZE) return len;

  append_block (buf, 0, buf, len, len);

  return out_len;
}

DECLSPEC int mangle_dupeword_times (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  const int out_len = (len * p0) + len;

  if (out_len >= RP_PASSWORD_SIZE) return len;

  int out_pos = len;

  for (int t = 0; t < p0; t++)
  {
    for (int i = 0; i < len; i++)
    {
      buf[out_pos] = buf[i];

      out_pos++;
    }
  }

  return out_len;
}

DECLSPEC int mangle_reflect (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u32 *buf, const int len)
{
  const int out_len = len * 2;

  if (out_len >= RP_PASSWORD_SIZE) return len;

  append_block (buf, 0, buf, len, len);

  for (int l = 0; l < len / 2; l++)
  {
    const int r = len - 1 - l;

    exchange_byte (buf, len + l, len + r);
  }

  return out_len;
}

DECLSPEC int mangle_append (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  const int out_len = len + 1;

  if (out_len >= RP_PASSWORD_SIZE) return len;

  buf[len] = p0;

  return out_len;
}

DECLSPEC int mangle_prepend (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  const int out_len = len + 1;

  if (out_len >= RP_PASSWORD_SIZE) return len;

  for (int pos = len - 1; pos >= 0; pos--)
  {
    buf[pos + 1] = buf[pos];
  }

  buf[0] = p0;

  return out_len;
}

DECLSPEC int mangle_rotate_left (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u32 *buf, const int len)
{
  for (int l = 0, r = len - 1; r > l; r--)
  {
    exchange_byte (buf, l, r);
  }

  return len;
}

DECLSPEC int mangle_rotate_right (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u32 *buf, const int len)
{
  for (int l = 0, r = len - 1; l < r; l++)
  {
    exchange_byte (buf, l, r);
  }

  return len;
}

DECLSPEC int mangle_delete_at (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  if (p0 >= len) return len;

  for (int pos = p0; pos < len - 1; pos++)
  {
    buf[pos] = buf[pos + 1];
  }

  buf[len - 1] = 0;

  return (len - 1);
}

DECLSPEC int mangle_delete_first (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  return mangle_delete_at (0, p1, buf, len);
}

DECLSPEC int mangle_delete_last (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  if (len == 0) return 0;

  return mangle_delete_at (len - 1, p1, buf, len);
}

DECLSPEC int mangle_extract (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  if (p0 >= len) return len;

  if ((p0 + p1) > len) return len;

  for (int pos = 0; pos < p1; pos++)
  {
    buf[pos] = buf[p0 + pos];
  }

  for (int pos = p1; pos < len; pos++)
  {
    buf[pos] = 0;
  }

  return p1;
}

DECLSPEC int mangle_omit (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  if (p0 >= len) return len;

  if ((p0 + p1) > len) return len;

  for (int pos = p0; pos < len - p1; pos++)
  {
    buf[pos] = buf[pos + p1];
  }

  for (int pos = len - p1; pos < len; pos++)
  {
    buf[pos] = 0;
  }

  return (len - p1);
}

DECLSPEC int mangle_insert (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  if (p0 >= len + 1) return len;

  const int out_len = len + 1;

  if (out_len >= RP_PASSWORD_SIZE) return len;

  for (int pos = len - 1; pos > p0 - 1; pos--)
  {
    buf[pos + 1] = buf[pos];
  }

  buf[p0] = p1;

  return out_len;
}

DECLSPEC int mangle_overstrike (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  if (p0 >= len) return len;

  buf[p0] = p1;

  return len;
}

DECLSPEC int mangle_truncate_at (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  if (p0 >= len) return len;

  for (int pos = p0; pos < len; pos++)
  {
    buf[pos] = 0;
  }

  return p0;
}

DECLSPEC int mangle_replace (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  for (int pos = 0; pos < len; pos++)
  {
    if (buf[pos] != p0) continue;

    buf[pos] = p1;
  }

  return len;
}

DECLSPEC int mangle_replace_class_l (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  for (int pos = 0; pos < len; pos++)
  {
    if (!is_l (buf[pos])) continue;

    buf[pos] = p1;
  }

  return len;
}

DECLSPEC int mangle_replace_class_u (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  for (int pos = 0; pos < len; pos++)
  {
    if (!is_u (buf[pos])) continue;

    buf[pos] = p1;
  }

  return len;
}

DECLSPEC int mangle_replace_class_d (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  for (int pos = 0; pos < len; pos++)
  {
    if (!is_d (buf[pos])) continue;

    buf[pos] = p1;
  }

  return len;
}

DECLSPEC int mangle_replace_class_lh (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  for (int pos = 0; pos < len; pos++)
  {
    if (!is_lh (buf[pos])) continue;

    buf[pos] = p1;
  }

  return len;
}

DECLSPEC int mangle_replace_class_uh (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  for (int pos = 0; pos < len; pos++)
  {
    if (!is_uh (buf[pos])) continue;

    buf[pos] = p1;
  }

  return len;
}

DECLSPEC int mangle_replace_class_s (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  for (int pos = 0; pos < len; pos++)
  {
    if (!is_s (buf[pos])) continue;

    buf[pos] = p1;
  }

  return len;
}

DECLSPEC int mangle_replace_class (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
       if (p0 == 'l') return mangle_replace_class_l  (p0, p1, buf, len);
  else if (p0 == 'u') return mangle_replace_class_u  (p0, p1, buf, len);
  else if (p0 == 'd') return mangle_replace_class_d  (p0, p1, buf, len);
  else if (p0 == 'h') return mangle_replace_class_lh (p0, p1, buf, len);
  else if (p0 == 'H') return mangle_replace_class_uh (p0, p1, buf, len);
  else if (p0 == 's') return mangle_replace_class_s  (p0, p1, buf, len);

  return len;
}

DECLSPEC int mangle_purgechar (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  int out_len = 0;

  for (int pos = 0; pos < len; pos++)
  {
    if (buf[pos] == p0) continue;

    buf[out_len] = buf[pos];

    out_len++;
  }

  for (int pos = out_len; pos < len; pos++)
  {
    buf[pos] = 0;
  }

  return out_len;
}

DECLSPEC int mangle_purgechar_class_l (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  int out_len = 0;

  for (int pos = 0; pos < len; pos++)
  {
    if (is_l (buf[pos])) continue;

    buf[out_len] = buf[pos];

    out_len++;
  }

  for (int pos = out_len; pos < len; pos++)
  {
    buf[pos] = 0;
  }

  return out_len;
}

DECLSPEC int mangle_purgechar_class_u (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  int out_len = 0;

  for (int pos = 0; pos < len; pos++)
  {
    if (is_u (buf[pos])) continue;

    buf[out_len] = buf[pos];

    out_len++;
  }

  for (int pos = out_len; pos < len; pos++)
  {
    buf[pos] = 0;
  }

  return out_len;
}

DECLSPEC int mangle_purgechar_class_d (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  int out_len = 0;

  for (int pos = 0; pos < len; pos++)
  {
    if (is_d (buf[pos])) continue;

    buf[out_len] = buf[pos];

    out_len++;
  }

  for (int pos = out_len; pos < len; pos++)
  {
    buf[pos] = 0;
  }

  return out_len;
}

DECLSPEC int mangle_purgechar_class_lh (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  int out_len = 0;

  for (int pos = 0; pos < len; pos++)
  {
    if (is_lh (buf[pos])) continue;

    buf[out_len] = buf[pos];

    out_len++;
  }

  for (int pos = out_len; pos < len; pos++)
  {
    buf[pos] = 0;
  }

  return out_len;
}

DECLSPEC int mangle_purgechar_class_uh (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  int out_len = 0;

  for (int pos = 0; pos < len; pos++)
  {
    if (is_uh (buf[pos])) continue;

    buf[out_len] = buf[pos];

    out_len++;
  }

  for (int pos = out_len; pos < len; pos++)
  {
    buf[pos] = 0;
  }

  return out_len;
}

DECLSPEC int mangle_purgechar_class_s (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  int out_len = 0;

  for (int pos = 0; pos < len; pos++)
  {
    if (is_s (buf[pos])) continue;

    buf[out_len] = buf[pos];

    out_len++;
  }

  for (int pos = out_len; pos < len; pos++)
  {
    buf[pos] = 0;
  }

  return out_len;
}

DECLSPEC int mangle_purgechar_class (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
       if (p0 == 'l') return mangle_purgechar_class_l  (p0, p1, buf, len);
  else if (p0 == 'u') return mangle_purgechar_class_u  (p0, p1, buf, len);
  else if (p0 == 'd') return mangle_purgechar_class_d  (p0, p1, buf, len);
  else if (p0 == 'h') return mangle_purgechar_class_lh (p0, p1, buf, len);
  else if (p0 == 'H') return mangle_purgechar_class_uh (p0, p1, buf, len);
  else if (p0 == 's') return mangle_purgechar_class_s  (p0, p1, buf, len);

  return len;
}

DECLSPEC int mangle_dupechar_first (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  const int out_len = len + p0;

  if (len     ==                0) return len;
  if (out_len >= RP_PASSWORD_SIZE) return len;

  const u8 c = buf[0];

  for (int i = 0; i < p0; i++)
  {
    mangle_prepend (c, 0, buf, len + i);
  }

  return out_len;
}

DECLSPEC int mangle_dupechar_last (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  const int out_len = len + p0;

  if (len     ==                0) return len;
  if (out_len >= RP_PASSWORD_SIZE) return len;

  const u8 c = buf[len - 1];

  for (int i = 0; i < p0; i++)
  {
    mangle_append (c, 0, buf, len + i);
  }

  return out_len;
}

DECLSPEC int mangle_dupechar_all (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  const int out_len = len + len;

  if (out_len >= RP_PASSWORD_SIZE) return len;

  for (int pos = len - 1; pos >= 0; pos--)
  {
    int new_pos = pos * 2;

    buf[new_pos] = buf[pos];

    buf[new_pos + 1] = buf[pos];
  }

  return out_len;
}

DECLSPEC int mangle_switch_first (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u32 *buf, const int len)
{
  if (len < 2) return len;

  exchange_byte (buf, 0, 1);

  return len;
}

DECLSPEC int mangle_switch_last (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u32 *buf, const int len)
{
  if (len < 2) return len;

  exchange_byte (buf, len - 2, len - 1);

  return len;
}

DECLSPEC int mangle_switch_at (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u32 *buf, const int len)
{
  if (p0 >= len) return len;
  if (p1 >= len) return len;

  exchange_byte (buf, p0, p1);

  return len;
}

DECLSPEC int mangle_chr_shiftl (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  if (p0 >= len) return len;

  buf[p0] <<= 1;

  return len;
}

DECLSPEC int mangle_chr_shiftr (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  if (p0 >= len) return len;

  buf[p0] >>= 1;

  return len;
}

DECLSPEC int mangle_chr_incr (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  if (p0 >= len) return len;

  buf[p0]++;

  return len;
}

DECLSPEC int mangle_chr_decr (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  if (p0 >= len) return len;

  buf[p0]--;

  return len;
}

DECLSPEC int mangle_replace_np1 (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  if ((p0 + 1) >= len) return len;

  buf[p0] = buf[p0 + 1];

  return len;
}

DECLSPEC int mangle_replace_nm1 (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  if (p0 == 0) return len;

  if (p0 >= len) return len;

  buf[p0] = buf[p0 - 1];

  return len;
}

DECLSPEC int mangle_dupeblock_first (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  if (p0 > len) return len;

  const int out_len = len + p0;

  if (out_len >= RP_PASSWORD_SIZE) return len;

  for (int i = 0; i < p0; i++)
  {
    const u8 c = buf[i * 2];

    mangle_insert (i, c, buf, len + i);
  }

  return out_len;
}

DECLSPEC int mangle_dupeblock_last (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u8 *buf, const int len)
{
  if (p0 > len) return len;

  const int out_len = len + p0;

  if (out_len >= RP_PASSWORD_SIZE) return len;

  for (int i = 0; i < p0; i++)
  {
    const u8 c = buf[len - p0 + i];

    mangle_append (c, 0, buf, len + i);
  }

  return out_len;
}

DECLSPEC int mangle_title_sep (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u32 *buf, const int len)
{
  if (len >= RP_PASSWORD_SIZE) return len;

  u32 rem = 0xff;

  for (int i = 0, idx = 0; i < len; i += 4, idx += 1)
  {
    const u32 t = buf[idx];

    buf[idx] = t | generate_cmask (t);

    u32 out = rem;

    rem = 0;

    if (((t >>  0) & 0xff) == p0) out |= 0x0000ff00;
    if (((t >>  8) & 0xff) == p0) out |= 0x00ff0000;
    if (((t >> 16) & 0xff) == p0) out |= 0xff000000;
    if (((t >> 24) & 0xff) == p0) rem |= 0x000000ff;

    buf[idx] &= ~(generate_cmask (buf[idx]) & out);
  }

  return len;
}

DECLSPEC int mangle_title_sep_class_l (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u32 *buf, const int len)
{
  if (len >= RP_PASSWORD_SIZE) return len;

  u32 rem = 0xff;

  for (int i = 0, idx = 0; i < len; i += 4, idx += 1)
  {
    const u32 t = buf[idx];

    buf[idx] = t | generate_cmask (t);

    u32 out = rem;

    rem = 0;

    if (is_l ((t >>  0) & 0xff)) out |= 0x0000ff00;
    if (is_l ((t >>  8) & 0xff)) out |= 0x00ff0000;
    if (is_l ((t >> 16) & 0xff)) out |= 0xff000000;
    if (is_l ((t >> 24) & 0xff)) rem |= 0x000000ff;

    buf[idx] &= ~(generate_cmask (buf[idx]) & out);
  }

  return len;
}

DECLSPEC int mangle_title_sep_class_u (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u32 *buf, const int len)
{
  if (len >= RP_PASSWORD_SIZE) return len;

  u32 rem = 0xff;

  for (int i = 0, idx = 0; i < len; i += 4, idx += 1)
  {
    const u32 t = buf[idx];

    buf[idx] = t | generate_cmask (t);

    u32 out = rem;

    rem = 0;

    if (is_u ((t >>  0) & 0xff)) out |= 0x0000ff00;
    if (is_u ((t >>  8) & 0xff)) out |= 0x00ff0000;
    if (is_u ((t >> 16) & 0xff)) out |= 0xff000000;
    if (is_u ((t >> 24) & 0xff)) rem |= 0x000000ff;

    buf[idx] &= ~(generate_cmask (buf[idx]) & out);
  }

  return len;
}

DECLSPEC int mangle_title_sep_class_d (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u32 *buf, const int len)
{
  if (len >= RP_PASSWORD_SIZE) return len;

  u32 rem = 0xff;

  for (int i = 0, idx = 0; i < len; i += 4, idx += 1)
  {
    const u32 t = buf[idx];

    buf[idx] = t | generate_cmask (t);

    u32 out = rem;

    rem = 0;

    if (is_d ((t >>  0) & 0xff)) out |= 0x0000ff00;
    if (is_d ((t >>  8) & 0xff)) out |= 0x00ff0000;
    if (is_d ((t >> 16) & 0xff)) out |= 0xff000000;
    if (is_d ((t >> 24) & 0xff)) rem |= 0x000000ff;

    buf[idx] &= ~(generate_cmask (buf[idx]) & out);
  }

  return len;
}

DECLSPEC int mangle_title_sep_class_lh (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u32 *buf, const int len)
{
  if (len >= RP_PASSWORD_SIZE) return len;

  u32 rem = 0xff;

  for (int i = 0, idx = 0; i < len; i += 4, idx += 1)
  {
    const u32 t = buf[idx];

    buf[idx] = t | generate_cmask (t);

    u32 out = rem;

    rem = 0;

    if (is_lh ((t >>  0) & 0xff)) out |= 0x0000ff00;
    if (is_lh ((t >>  8) & 0xff)) out |= 0x00ff0000;
    if (is_lh ((t >> 16) & 0xff)) out |= 0xff000000;
    if (is_lh ((t >> 24) & 0xff)) rem |= 0x000000ff;

    buf[idx] &= ~(generate_cmask (buf[idx]) & out);
  }

  return len;
}

DECLSPEC int mangle_title_sep_class_uh (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u32 *buf, const int len)
{
  if (len >= RP_PASSWORD_SIZE) return len;

  u32 rem = 0xff;

  for (int i = 0, idx = 0; i < len; i += 4, idx += 1)
  {
    const u32 t = buf[idx];

    buf[idx] = t | generate_cmask (t);

    u32 out = rem;

    rem = 0;

    if (is_uh ((t >>  0) & 0xff)) out |= 0x0000ff00;
    if (is_uh ((t >>  8) & 0xff)) out |= 0x00ff0000;
    if (is_uh ((t >> 16) & 0xff)) out |= 0xff000000;
    if (is_uh ((t >> 24) & 0xff)) rem |= 0x000000ff;

    buf[idx] &= ~(generate_cmask (buf[idx]) & out);
  }

  return len;
}

DECLSPEC int mangle_title_sep_class_s (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u32 *buf, const int len)
{
  if (len >= RP_PASSWORD_SIZE) return len;

  u32 rem = 0xff;

  for (int i = 0, idx = 0; i < len; i += 4, idx += 1)
  {
    const u32 t = buf[idx];

    buf[idx] = t | generate_cmask (t);

    u32 out = rem;

    rem = 0;

    if (is_s ((t >>  0) & 0xff)) out |= 0x0000ff00;
    if (is_s ((t >>  8) & 0xff)) out |= 0x00ff0000;
    if (is_s ((t >> 16) & 0xff)) out |= 0xff000000;
    if (is_s ((t >> 24) & 0xff)) rem |= 0x000000ff;

    buf[idx] &= ~(generate_cmask (buf[idx]) & out);
  }

  return len;
}

DECLSPEC int mangle_title_sep_class (MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u32 *buf, const int len)
{
       if (p0 == 'l') return mangle_title_sep_class_l  (p0, p1, buf, len);
  else if (p0 == 'u') return mangle_title_sep_class_u  (p0, p1, buf, len);
  else if (p0 == 'd') return mangle_title_sep_class_d  (p0, p1, buf, len);
  else if (p0 == 'h') return mangle_title_sep_class_lh (p0, p1, buf, len);
  else if (p0 == 'H') return mangle_title_sep_class_uh (p0, p1, buf, len);
  else if (p0 == 's') return mangle_title_sep_class_s  (p0, p1, buf, len);

  return len;
}

DECLSPEC int apply_rule (const u32 name, MAYBE_UNUSED const u8 p0, MAYBE_UNUSED const u8 p1, PRIVATE_AS u32 *buf, const int in_len)
{
  int out_len = in_len;

  switch (name)
  {
    case RULE_OP_MANGLE_LREST:            out_len = mangle_lrest            (p0, p1,                   buf, out_len); break;
    case RULE_OP_MANGLE_LREST_UFIRST:     out_len = mangle_lrest_ufirst     (p0, p1,                   buf, out_len); break;
    case RULE_OP_MANGLE_UREST:            out_len = mangle_urest            (p0, p1,                   buf, out_len); break;
    case RULE_OP_MANGLE_UREST_LFIRST:     out_len = mangle_urest_lfirst     (p0, p1,                   buf, out_len); break;
    case RULE_OP_MANGLE_TREST:            out_len = mangle_trest            (p0, p1,                   buf, out_len); break;
    case RULE_OP_MANGLE_TOGGLE_AT:        out_len = mangle_toggle_at        (p0, p1,                   buf, out_len); break;
    case RULE_OP_MANGLE_TOGGLE_AT_SEP:    out_len = mangle_toggle_at_sep    (p0, p1,                   buf, out_len); break;
    case RULE_OP_MANGLE_REVERSE:          out_len = mangle_reverse          (p0, p1,                   buf, out_len); break;
    case RULE_OP_MANGLE_DUPEWORD:         out_len = mangle_dupeword         (p0, p1,                   buf, out_len); break;
    case RULE_OP_MANGLE_DUPEWORD_TIMES:   out_len = mangle_dupeword_times   (p0, p1, (PRIVATE_AS u8 *) buf, out_len); break;
    case RULE_OP_MANGLE_REFLECT:          out_len = mangle_reflect          (p0, p1,                   buf, out_len); break;
    case RULE_OP_MANGLE_APPEND:           out_len = mangle_append           (p0, p1, (PRIVATE_AS u8 *) buf, out_len); break;
    case RULE_OP_MANGLE_PREPEND:          out_len = mangle_prepend          (p0, p1, (PRIVATE_AS u8 *) buf, out_len); break;
    case RULE_OP_MANGLE_ROTATE_LEFT:      out_len = mangle_rotate_left      (p0, p1,                   buf, out_len); break;
    case RULE_OP_MANGLE_ROTATE_RIGHT:     out_len = mangle_rotate_right     (p0, p1,                   buf, out_len); break;
    case RULE_OP_MANGLE_DELETE_FIRST:     out_len = mangle_delete_first     (p0, p1, (PRIVATE_AS u8 *) buf, out_len); break;
    case RULE_OP_MANGLE_DELETE_LAST:      out_len = mangle_delete_last      (p0, p1, (PRIVATE_AS u8 *) buf, out_len); break;
    case RULE_OP_MANGLE_DELETE_AT:        out_len = mangle_delete_at        (p0, p1, (PRIVATE_AS u8 *) buf, out_len); break;
    case RULE_OP_MANGLE_EXTRACT:          out_len = mangle_extract          (p0, p1, (PRIVATE_AS u8 *) buf, out_len); break;
    case RULE_OP_MANGLE_OMIT:             out_len = mangle_omit             (p0, p1, (PRIVATE_AS u8 *) buf, out_len); break;
    case RULE_OP_MANGLE_INSERT:           out_len = mangle_insert           (p0, p1, (PRIVATE_AS u8 *) buf, out_len); break;
    case RULE_OP_MANGLE_OVERSTRIKE:       out_len = mangle_overstrike       (p0, p1, (PRIVATE_AS u8 *) buf, out_len); break;
    case RULE_OP_MANGLE_TRUNCATE_AT:      out_len = mangle_truncate_at      (p0, p1, (PRIVATE_AS u8 *) buf, out_len); break;
    case RULE_OP_MANGLE_REPLACE:          out_len = mangle_replace          (p0, p1, (PRIVATE_AS u8 *) buf, out_len); break;
    case RULE_OP_MANGLE_REPLACE_CLASS:    out_len = mangle_replace_class    (p0, p1, (PRIVATE_AS u8 *) buf, out_len); break;
    case RULE_OP_MANGLE_PURGECHAR:        out_len = mangle_purgechar        (p0, p1, (PRIVATE_AS u8 *) buf, out_len); break;
    case RULE_OP_MANGLE_PURGECHAR_CLASS:  out_len = mangle_purgechar_class  (p0, p1, (PRIVATE_AS u8 *) buf, out_len); break;
    case RULE_OP_MANGLE_DUPECHAR_FIRST:   out_len = mangle_dupechar_first   (p0, p1, (PRIVATE_AS u8 *) buf, out_len); break;
    case RULE_OP_MANGLE_DUPECHAR_LAST:    out_len = mangle_dupechar_last    (p0, p1, (PRIVATE_AS u8 *) buf, out_len); break;
    case RULE_OP_MANGLE_DUPECHAR_ALL:     out_len = mangle_dupechar_all     (p0, p1, (PRIVATE_AS u8 *) buf, out_len); break;
    case RULE_OP_MANGLE_SWITCH_FIRST:     out_len = mangle_switch_first     (p0, p1,                   buf, out_len); break;
    case RULE_OP_MANGLE_SWITCH_LAST:      out_len = mangle_switch_last      (p0, p1,                   buf, out_len); break;
    case RULE_OP_MANGLE_SWITCH_AT:        out_len = mangle_switch_at        (p0, p1,                   buf, out_len); break;
    case RULE_OP_MANGLE_CHR_SHIFTL:       out_len = mangle_chr_shiftl       (p0, p1, (PRIVATE_AS u8 *) buf, out_len); break;
    case RULE_OP_MANGLE_CHR_SHIFTR:       out_len = mangle_chr_shiftr       (p0, p1, (PRIVATE_AS u8 *) buf, out_len); break;
    case RULE_OP_MANGLE_CHR_INCR:         out_len = mangle_chr_incr         (p0, p1, (PRIVATE_AS u8 *) buf, out_len); break;
    case RULE_OP_MANGLE_CHR_DECR:         out_len = mangle_chr_decr         (p0, p1, (PRIVATE_AS u8 *) buf, out_len); break;
    case RULE_OP_MANGLE_REPLACE_NP1:      out_len = mangle_replace_np1      (p0, p1, (PRIVATE_AS u8 *) buf, out_len); break;
    case RULE_OP_MANGLE_REPLACE_NM1:      out_len = mangle_replace_nm1      (p0, p1, (PRIVATE_AS u8 *) buf, out_len); break;
    case RULE_OP_MANGLE_DUPEBLOCK_FIRST:  out_len = mangle_dupeblock_first  (p0, p1, (PRIVATE_AS u8 *) buf, out_len); break;
    case RULE_OP_MANGLE_DUPEBLOCK_LAST:   out_len = mangle_dupeblock_last   (p0, p1, (PRIVATE_AS u8 *) buf, out_len); break;
    case RULE_OP_MANGLE_TITLE_SEP:        out_len = mangle_title_sep        (p0, p1,                   buf, out_len); break;
    case RULE_OP_MANGLE_TITLE_SEP_CLASS:  out_len = mangle_title_sep_class  (p0, p1,                   buf, out_len); break;
    case RULE_OP_MANGLE_TITLE:            out_len = mangle_title_sep        (' ', p1,                  buf, out_len); break;
  }

  return out_len;
}

DECLSPEC int apply_rules (CONSTANT_AS const u32 *cmds, PRIVATE_AS u32 *buf, const int in_len)
{
  int out_len = in_len;

  for (u32 i = 0; cmds[i] != 0; i++)
  {
    const u32 cmd = cmds[i];

    const u8 name = (cmd >>  0) & 0xff;
    const u8 p0   = (cmd >>  8) & 0xff;
    const u8 p1   = (cmd >> 16) & 0xff;

    // we need to guarantee input length < 256 otherwise functions like rule_op_mangle_switch_last() and others will read out of boundary
    out_len = apply_rule (name, p0, p1, buf, out_len);
  }

  return out_len;
}