/* SPDX-License-Identifier: GPL-2.0-or-later
 * Copyright 2006 Blender Foundation. All rights reserved. */

/** \file
 * \ingroup texnodes
 */

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

static bNodeSocketTemplate inputs[] = {
    {SOCK_FLOAT, N_("Hue"), 0.0f, 0.0f, 0.0f, 0.0f, -0.5f, 0.5f, PROP_NONE},
    {SOCK_FLOAT, N_("Saturation"), 1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 2.0f, PROP_NONE},
    {SOCK_FLOAT, N_("Value"), 1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 2.0f, PROP_NONE},
    {SOCK_FLOAT, N_("Factor"), 1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f, PROP_NONE},
    {SOCK_RGBA, N_("Color"), 0.8f, 0.8f, 0.8f, 1.0f},
    {-1, ""},
};
static bNodeSocketTemplate outputs[] = {
    {SOCK_RGBA, N_("Color")},
    {-1, ""},
};

static void do_hue_sat_fac(
    bNode *UNUSED(node), float *out, float hue, float sat, float val, float *in, float fac)
{
  if (fac != 0 && (hue != 0.5f || sat != 1 || val != 1)) {
    float col[3], hsv[3], mfac = 1.0f - fac;

    rgb_to_hsv(in[0], in[1], in[2], hsv, hsv + 1, hsv + 2);
    hsv[0] += (hue - 0.5f);
    if (hsv[0] > 1.0f) {
      hsv[0] -= 1.0f;
    }
    else if (hsv[0] < 0.0f) {
      hsv[0] += 1.0f;
    }
    hsv[1] *= sat;
    if (hsv[1] > 1.0f) {
      hsv[1] = 1.0f;
    }
    else if (hsv[1] < 0.0f) {
      hsv[1] = 0.0f;
    }
    hsv[2] *= val;
    if (hsv[2] > 1.0f) {
      hsv[2] = 1.0f;
    }
    else if (hsv[2] < 0.0f) {
      hsv[2] = 0.0f;
    }
    hsv_to_rgb(hsv[0], hsv[1], hsv[2], col, col + 1, col + 2);

    out[0] = mfac * in[0] + fac * col[0];
    out[1] = mfac * in[1] + fac * col[1];
    out[2] = mfac * in[2] + fac * col[2];
  }
  else {
    copy_v4_v4(out, in);
  }
}

static void colorfn(float *out, TexParams *p, bNode *node, bNodeStack **in, short thread)
{
  float hue = tex_input_value(in[0], p, thread);
  float sat = tex_input_value(in[1], p, thread);
  float val = tex_input_value(in[2], p, thread);
  float fac = tex_input_value(in[3], p, thread);

  float col[4];
  tex_input_rgba(col, in[4], p, thread);

  hue += 0.5f; /* [-0.5, 0.5] -> [0, 1] */

  do_hue_sat_fac(node, out, hue, sat, val, col, fac);

  out[3] = col[3];
}

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

void register_node_type_tex_hue_sat(void)
{
  static bNodeType ntype;

  tex_node_type_base(&ntype, TEX_NODE_HUE_SAT, "Hue Saturation Value", NODE_CLASS_OP_COLOR);
  node_type_socket_templates(&ntype, inputs, outputs);
  node_type_size_preset(&ntype, NODE_SIZE_MIDDLE);
  ntype.exec_fn = exec;

  nodeRegisterType(&ntype);
}