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

#ifdef KERNEL_STATIC
#include "inc_vendor.h"
#include "inc_types.h"
#include "inc_common.cl"
#include "inc_hash_sha256.cl"
#endif

#define COMPARE_S "inc_comp_single.cl"
#define COMPARE_M "inc_comp_multi.cl"

typedef struct
{
  #ifndef SCRYPT_TMP_ELEM
  #define SCRYPT_TMP_ELEM 1
  #endif

  uint4 P[SCRYPT_TMP_ELEM];

} scrypt_tmp_t;

DECLSPEC static uint4 hc_swap32_4 (uint4 v)
{
  return (rotate ((v & 0x00FF00FF), 24u) | rotate ((v & 0xFF00FF00),  8u));
}

#define GET_SCRYPT_CNT(r,p) (2 * (r) * 16 * (p))
#define GET_SMIX_CNT(r,N)   (2 * (r) * 16 * (N))
#define GET_STATE_CNT(r)    (2 * (r) * 16)

#define SCRYPT_CNT  GET_SCRYPT_CNT (SCRYPT_R, SCRYPT_P)
#define SCRYPT_CNT4 (SCRYPT_CNT / 4)
#define STATE_CNT   GET_STATE_CNT  (SCRYPT_R)
#define STATE_CNT4  (STATE_CNT / 4)

#define ADD_ROTATE_XOR(r,i1,i2,s) (r) ^= rotate ((i1) + (i2), (s));

#define SALSA20_2R()                \
{                                   \
  ADD_ROTATE_XOR (X1, X0, X3,  7);  \
  ADD_ROTATE_XOR (X2, X1, X0,  9);  \
  ADD_ROTATE_XOR (X3, X2, X1, 13);  \
  ADD_ROTATE_XOR (X0, X3, X2, 18);  \
                                    \
  X1 = X1.s3012;                    \
  X2 = X2.s2301;                    \
  X3 = X3.s1230;                    \
                                    \
  ADD_ROTATE_XOR (X3, X0, X1,  7);  \
  ADD_ROTATE_XOR (X2, X3, X0,  9);  \
  ADD_ROTATE_XOR (X1, X2, X3, 13);  \
  ADD_ROTATE_XOR (X0, X1, X2, 18);  \
                                    \
  X1 = X1.s1230;                    \
  X2 = X2.s2301;                    \
  X3 = X3.s3012;                    \
}

#define SALSA20_8_XOR() \
{                       \
  R0 = R0 ^ Y0;         \
  R1 = R1 ^ Y1;         \
  R2 = R2 ^ Y2;         \
  R3 = R3 ^ Y3;         \
                        \
  uint4 X0 = R0;        \
  uint4 X1 = R1;        \
  uint4 X2 = R2;        \
  uint4 X3 = R3;        \
                        \
  SALSA20_2R ();        \
  SALSA20_2R ();        \
  SALSA20_2R ();        \
  SALSA20_2R ();        \
                        \
  R0 = R0 + X0;         \
  R1 = R1 + X1;         \
  R2 = R2 + X2;         \
  R3 = R3 + X3;         \
}

DECLSPEC static void salsa_r (uint4 *TI)
{
  uint4 R0 = TI[STATE_CNT4 - 4];
  uint4 R1 = TI[STATE_CNT4 - 3];
  uint4 R2 = TI[STATE_CNT4 - 2];
  uint4 R3 = TI[STATE_CNT4 - 1];

  uint4 TO[STATE_CNT4];

  int idx_y  = 0;
  int idx_r1 = 0;
  int idx_r2 = SCRYPT_R * 4;

  for (int i = 0; i < SCRYPT_R; i++)
  {
    uint4 Y0;
    uint4 Y1;
    uint4 Y2;
    uint4 Y3;

    Y0 = TI[idx_y++];
    Y1 = TI[idx_y++];
    Y2 = TI[idx_y++];
    Y3 = TI[idx_y++];

    SALSA20_8_XOR ();

    TO[idx_r1++] = R0;
    TO[idx_r1++] = R1;
    TO[idx_r1++] = R2;
    TO[idx_r1++] = R3;

    Y0 = TI[idx_y++];
    Y1 = TI[idx_y++];
    Y2 = TI[idx_y++];
    Y3 = TI[idx_y++];

    SALSA20_8_XOR ();

    TO[idx_r2++] = R0;
    TO[idx_r2++] = R1;
    TO[idx_r2++] = R2;
    TO[idx_r2++] = R3;
  }

  #pragma unroll
  for (int i = 0; i < STATE_CNT4; i++)
  {
    TI[i] = TO[i];
  }
}

DECLSPEC static void scrypt_smix (uint4 *X, uint4 *T, GLOBAL_AS uint4 *V0, GLOBAL_AS uint4 *V1, GLOBAL_AS uint4 *V2, GLOBAL_AS uint4 *V3)
{
  #define Coord(xd4,y,z) (((xd4) * ySIZE * zSIZE) + ((y) * zSIZE) + (z))
  #define CO Coord(xd4,y,z)

  const u32 ySIZE = SCRYPT_N / SCRYPT_TMTO;
  const u32 zSIZE = STATE_CNT4;

  const u32 x = get_global_id (0);

  const u32 xd4 = x / 4;
  const u32 xm4 = x & 3;

  GLOBAL_AS uint4 *V;

  switch (xm4)
  {
    case 0: V = V0; break;
    case 1: V = V1; break;
    case 2: V = V2; break;
    case 3: V = V3; break;
  }

  #ifdef _unroll
  #pragma unroll
  #endif
  for (u32 i = 0; i < STATE_CNT4; i += 4)
  {
    T[0] = (uint4) (X[i + 0].x, X[i + 1].y, X[i + 2].z, X[i + 3].w);
    T[1] = (uint4) (X[i + 1].x, X[i + 2].y, X[i + 3].z, X[i + 0].w);
    T[2] = (uint4) (X[i + 2].x, X[i + 3].y, X[i + 0].z, X[i + 1].w);
    T[3] = (uint4) (X[i + 3].x, X[i + 0].y, X[i + 1].z, X[i + 2].w);

    X[i + 0] = T[0];
    X[i + 1] = T[1];
    X[i + 2] = T[2];
    X[i + 3] = T[3];
  }

  for (u32 y = 0; y < ySIZE; y++)
  {
    for (u32 z = 0; z < zSIZE; z++) V[CO] = X[z];

    for (u32 i = 0; i < SCRYPT_TMTO; i++) salsa_r (X);
  }

  for (u32 i = 0; i < SCRYPT_N; i++)
  {
    const u32 k = X[zSIZE - 4].x & (SCRYPT_N - 1);

    const u32 y = k / SCRYPT_TMTO;

    const u32 km = k - (y * SCRYPT_TMTO);

    for (u32 z = 0; z < zSIZE; z++) T[z] = V[CO];

    for (u32 i = 0; i < km; i++) salsa_r (T);

    for (u32 z = 0; z < zSIZE; z++) X[z] ^= T[z];

    salsa_r (X);
  }

  #ifdef _unroll
  #pragma unroll
  #endif
  for (u32 i = 0; i < STATE_CNT4; i += 4)
  {
    T[0] = (uint4) (X[i + 0].x, X[i + 3].y, X[i + 2].z, X[i + 1].w);
    T[1] = (uint4) (X[i + 1].x, X[i + 0].y, X[i + 3].z, X[i + 2].w);
    T[2] = (uint4) (X[i + 2].x, X[i + 1].y, X[i + 0].z, X[i + 3].w);
    T[3] = (uint4) (X[i + 3].x, X[i + 2].y, X[i + 1].z, X[i + 0].w);

    X[i + 0] = T[0];
    X[i + 1] = T[1];
    X[i + 2] = T[2];
    X[i + 3] = T[3];
  }
}

KERNEL_FQ void m08900_init (KERN_ATTR_TMPS (scrypt_tmp_t))
{
  /**
   * base
   */

  const u64 gid = get_global_id (0);

  if (gid >= gid_max) return;

  sha256_hmac_ctx_t sha256_hmac_ctx;

  sha256_hmac_init_global_swap (&sha256_hmac_ctx, pws[gid].i, pws[gid].pw_len);

  sha256_hmac_update_global_swap (&sha256_hmac_ctx, salt_bufs[salt_pos].salt_buf, salt_bufs[salt_pos].salt_len);

  for (u32 i = 0, j = 1, k = 0; i < SCRYPT_CNT; i += 8, j += 1, k += 2)
  {
    sha256_hmac_ctx_t sha256_hmac_ctx2 = sha256_hmac_ctx;

    u32 w0[4];
    u32 w1[4];
    u32 w2[4];
    u32 w3[4];

    w0[0] = j;
    w0[1] = 0;
    w0[2] = 0;
    w0[3] = 0;
    w1[0] = 0;
    w1[1] = 0;
    w1[2] = 0;
    w1[3] = 0;
    w2[0] = 0;
    w2[1] = 0;
    w2[2] = 0;
    w2[3] = 0;
    w3[0] = 0;
    w3[1] = 0;
    w3[2] = 0;
    w3[3] = 0;

    sha256_hmac_update_64 (&sha256_hmac_ctx2, w0, w1, w2, w3, 4);

    sha256_hmac_final (&sha256_hmac_ctx2);

    u32 digest[8];

    digest[0] = sha256_hmac_ctx2.opad.h[0];
    digest[1] = sha256_hmac_ctx2.opad.h[1];
    digest[2] = sha256_hmac_ctx2.opad.h[2];
    digest[3] = sha256_hmac_ctx2.opad.h[3];
    digest[4] = sha256_hmac_ctx2.opad.h[4];
    digest[5] = sha256_hmac_ctx2.opad.h[5];
    digest[6] = sha256_hmac_ctx2.opad.h[6];
    digest[7] = sha256_hmac_ctx2.opad.h[7];

    const uint4 tmp0 = (uint4) (digest[0], digest[1], digest[2], digest[3]);
    const uint4 tmp1 = (uint4) (digest[4], digest[5], digest[6], digest[7]);

    tmps[gid].P[k + 0] = tmp0;
    tmps[gid].P[k + 1] = tmp1;
  }
}

KERNEL_FQ void m08900_loop (KERN_ATTR_TMPS (scrypt_tmp_t))
{
  const u64 gid = get_global_id (0);

  if (gid >= gid_max) return;

  GLOBAL_AS uint4 *d_scrypt0_buf = d_extra0_buf;
  GLOBAL_AS uint4 *d_scrypt1_buf = d_extra1_buf;
  GLOBAL_AS uint4 *d_scrypt2_buf = d_extra2_buf;
  GLOBAL_AS uint4 *d_scrypt3_buf = d_extra3_buf;

  uint4 X[STATE_CNT4];
  uint4 T[STATE_CNT4];

  #ifdef _unroll
  #pragma unroll
  #endif
  for (int z = 0; z < STATE_CNT4; z++) X[z] = hc_swap32_4 (tmps[gid].P[z]);

  scrypt_smix (X, T, d_scrypt0_buf, d_scrypt1_buf, d_scrypt2_buf, d_scrypt3_buf);

  #ifdef _unroll
  #pragma unroll
  #endif
  for (int z = 0; z < STATE_CNT4; z++) tmps[gid].P[z] = hc_swap32_4 (X[z]);

  #if SCRYPT_P >= 1
  for (int i = STATE_CNT4; i < SCRYPT_CNT4; i += STATE_CNT4)
  {
    for (int z = 0; z < STATE_CNT4; z++) X[z] = hc_swap32_4 (tmps[gid].P[i + z]);

    scrypt_smix (X, T, d_scrypt0_buf, d_scrypt1_buf, d_scrypt2_buf, d_scrypt3_buf);

    for (int z = 0; z < STATE_CNT4; z++) tmps[gid].P[i + z] = hc_swap32_4 (X[z]);
  }
  #endif
}

KERNEL_FQ void m08900_comp (KERN_ATTR_TMPS (scrypt_tmp_t))
{
  /**
   * base
   */

  const u64 gid = get_global_id (0);
  const u64 lid = get_local_id (0);

  if (gid >= gid_max) return;

  /**
   * 2nd pbkdf2, creates B
   */

  u32 w0[4];
  u32 w1[4];
  u32 w2[4];
  u32 w3[4];

  sha256_hmac_ctx_t ctx;

  sha256_hmac_init_global_swap (&ctx, pws[gid].i, pws[gid].pw_len);

  for (u32 l = 0; l < SCRYPT_CNT4; l += 4)
  {
    uint4 tmp;

    tmp = tmps[gid].P[l + 0];

    w0[0] = tmp.s0;
    w0[1] = tmp.s1;
    w0[2] = tmp.s2;
    w0[3] = tmp.s3;

    tmp = tmps[gid].P[l + 1];

    w1[0] = tmp.s0;
    w1[1] = tmp.s1;
    w1[2] = tmp.s2;
    w1[3] = tmp.s3;

    tmp = tmps[gid].P[l + 2];

    w2[0] = tmp.s0;
    w2[1] = tmp.s1;
    w2[2] = tmp.s2;
    w2[3] = tmp.s3;

    tmp = tmps[gid].P[l + 3];

    w3[0] = tmp.s0;
    w3[1] = tmp.s1;
    w3[2] = tmp.s2;
    w3[3] = tmp.s3;

    sha256_hmac_update_64 (&ctx, w0, w1, w2, w3, 64);
  }

  w0[0] = 1;
  w0[1] = 0;
  w0[2] = 0;
  w0[3] = 0;
  w1[0] = 0;
  w1[1] = 0;
  w1[2] = 0;
  w1[3] = 0;
  w2[0] = 0;
  w2[1] = 0;
  w2[2] = 0;
  w2[3] = 0;
  w3[0] = 0;
  w3[1] = 0;
  w3[2] = 0;
  w3[3] = 0;

  sha256_hmac_update_64 (&ctx, w0, w1, w2, w3, 4);

  sha256_hmac_final (&ctx);

  const u32 r0 = hc_swap32_S (ctx.opad.h[DGST_R0]);
  const u32 r1 = hc_swap32_S (ctx.opad.h[DGST_R1]);
  const u32 r2 = hc_swap32_S (ctx.opad.h[DGST_R2]);
  const u32 r3 = hc_swap32_S (ctx.opad.h[DGST_R3]);

  #define il_pos 0

  #ifdef KERNEL_STATIC
  #include COMPARE_M
  #endif
}