/*
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * The Original Code is Copyright (C) 2005 Blender Foundation.
 * All rights reserved.
 */

/** \file
 * \ingroup texnodes
 */

#include "node_texture_util.h"
#include "NOD_texture.h"

/* **************** SCALAR MATH ******************** */
static bNodeSocketTemplate inputs[] = {
    {SOCK_FLOAT, 1, N_("Value"), 0.5f, 0.5f, 0.5f, 1.0f, -100.0f, 100.0f, PROP_NONE},
    {SOCK_FLOAT, 1, N_("Value"), 0.5f, 0.5f, 0.5f, 1.0f, -100.0f, 100.0f, PROP_NONE},
    {-1, 0, ""},
};

static bNodeSocketTemplate outputs[] = {
    {SOCK_FLOAT, 0, N_("Value")},
    {-1, 0, ""},
};

static void valuefn(float *out, TexParams *p, bNode *node, bNodeStack **in, short thread)
{
  float in0 = tex_input_value(in[0], p, thread);
  float in1 = tex_input_value(in[1], p, thread);

  switch (node->custom1) {

    case NODE_MATH_ADD:
      *out = in0 + in1;
      break;
    case NODE_MATH_SUB:
      *out = in0 - in1;
      break;
    case NODE_MATH_MUL:
      *out = in0 * in1;
      break;
    case NODE_MATH_DIVIDE: {
      if (in1 == 0) {
        /* We don't want to divide by zero. */
        *out = 0.0;
      }
      else {
        *out = in0 / in1;
      }
      break;
    }
    case NODE_MATH_SIN: {
      *out = sinf(in0);
      break;
    }
    case NODE_MATH_COS: {
      *out = cosf(in0);
      break;
    }
    case NODE_MATH_TAN: {
      *out = tanf(in0);
      break;
    }
    case NODE_MATH_ASIN: {
      /* Can't do the impossible... */
      if (in0 <= 1 && in0 >= -1) {
        *out = asinf(in0);
      }
      else {
        *out = 0.0;
      }
      break;
    }
    case NODE_MATH_ACOS: {
      /* Can't do the impossible... */
      if (in0 <= 1 && in0 >= -1) {
        *out = acosf(in0);
      }
      else {
        *out = 0.0;
      }
      break;
    }
    case NODE_MATH_ATAN: {
      *out = atan(in0);
      break;
    }
    case NODE_MATH_POW: {
      /* Only raise negative numbers by full integers */
      if (in0 >= 0) {
        out[0] = pow(in0, in1);
      }
      else {
        float y_mod_1 = fmod(in1, 1);
        if (y_mod_1 > 0.999f || y_mod_1 < 0.001f) {
          *out = pow(in0, floor(in1 + 0.5f));
        }
        else {
          *out = 0.0;
        }
      }
      break;
    }
    case NODE_MATH_LOG: {
      /* Don't want any imaginary numbers... */
      if (in0 > 0 && in1 > 0) {
        *out = log(in0) / log(in1);
      }
      else {
        *out = 0.0;
      }
      break;
    }
    case NODE_MATH_MIN: {
      if (in0 < in1) {
        *out = in0;
      }
      else {
        *out = in1;
      }
      break;
    }
    case NODE_MATH_MAX: {
      if (in0 > in1) {
        *out = in0;
      }
      else {
        *out = in1;
      }
      break;
    }
    case NODE_MATH_ROUND: {
      *out = (in0 < 0) ? (int)(in0 - 0.5f) : (int)(in0 + 0.5f);
      break;
    }

    case NODE_MATH_LESS: {
      if (in0 < in1) {
        *out = 1.0f;
      }
      else {
        *out = 0.0f;
      }
      break;
    }

    case NODE_MATH_GREATER: {
      if (in0 > in1) {
        *out = 1.0f;
      }
      else {
        *out = 0.0f;
      }
      break;
    }

    case NODE_MATH_MOD: {
      if (in1 == 0.0f) {
        *out = 0.0f;
      }
      else {
        *out = fmod(in0, in1);
      }
      break;
    }

    case NODE_MATH_ABS: {
      *out = fabsf(in0);
      break;
    }

    case NODE_MATH_ATAN2: {
      *out = atan2(in0, in1);
      break;
    }

    case NODE_MATH_FLOOR: {
      *out = floorf(in0);
      break;
    }

    case NODE_MATH_CEIL: {
      *out = ceilf(in0);
      break;
    }

    case NODE_MATH_FRACT: {
      *out = in0 - floorf(in0);
      break;
    }

    case NODE_MATH_SQRT: {
      if (in0 > 0.0f) {
        *out = sqrtf(in0);
      }
      else {
        *out = 0.0f;
      }
      break;
    }

    default: {
      BLI_assert(0);
      break;
    }
  }

  if (node->custom2 & SHD_MATH_CLAMP) {
    CLAMP(*out, 0.0f, 1.0f);
  }
}

static void exec(void *data,
                 int UNUSED(thread),
                 bNode *node,
                 bNodeExecData *execdata,
                 bNodeStack **in,
                 bNodeStack **out)
{
  tex_output(node, execdata, in, out[0], &valuefn, data);
}

void register_node_type_tex_math(void)
{
  static bNodeType ntype;

  tex_node_type_base(&ntype, TEX_NODE_MATH, "Math", NODE_CLASS_CONVERTOR, 0);
  node_type_socket_templates(&ntype, inputs, outputs);
  node_type_label(&ntype, node_math_label);
  node_type_storage(&ntype, "", NULL, NULL);
  node_type_exec(&ntype, NULL, NULL, exec);

  nodeRegisterType(&ntype);
}
