/* SPDX-License-Identifier: GPL-2.0-or-later
 * Copyright 2005 Blender Foundation. All rights reserved. */

/** \file
 * \ingroup gpu
 */

#include "BLI_string.h"

#include "GPU_framebuffer.h"
#include "GPU_texture.h"

#include "gpu_backend.hh"
#include "gpu_context_private.hh"
#include "gpu_framebuffer_private.hh"
#include "gpu_vertex_buffer_private.hh"

#include "gpu_texture_private.hh"

namespace blender::gpu {

/* -------------------------------------------------------------------- */
/** \name Creation & Deletion
 * \{ */

Texture::Texture(const char *name)
{
  if (name) {
    BLI_strncpy(name_, name, sizeof(name_));
  }
  else {
    name_[0] = '\0';
  }

  for (int i = 0; i < ARRAY_SIZE(fb_); i++) {
    fb_[i] = nullptr;
  }
}

Texture::~Texture()
{
  for (int i = 0; i < ARRAY_SIZE(fb_); i++) {
    if (fb_[i] != nullptr) {
      fb_[i]->attachment_remove(fb_attachment_[i]);
    }
  }

#ifndef GPU_NO_USE_PY_REFERENCES
  if (this->py_ref) {
    *this->py_ref = nullptr;
  }
#endif
}

bool Texture::init_1D(int w, int layers, int mips, eGPUTextureFormat format)
{
  w_ = w;
  h_ = layers;
  d_ = 0;
  int mips_max = 1 + floorf(log2f(w));
  mipmaps_ = min_ii(mips, mips_max);
  format_ = format;
  format_flag_ = to_format_flag(format);
  type_ = (layers > 0) ? GPU_TEXTURE_1D_ARRAY : GPU_TEXTURE_1D;
  if ((format_flag_ & (GPU_FORMAT_DEPTH_STENCIL | GPU_FORMAT_INTEGER)) == 0) {
    sampler_state = GPU_SAMPLER_FILTER;
  }
  return this->init_internal();
}

bool Texture::init_2D(int w, int h, int layers, int mips, eGPUTextureFormat format)
{
  w_ = w;
  h_ = h;
  d_ = layers;
  int mips_max = 1 + floorf(log2f(max_ii(w, h)));
  mipmaps_ = min_ii(mips, mips_max);
  format_ = format;
  format_flag_ = to_format_flag(format);
  type_ = (layers > 0) ? GPU_TEXTURE_2D_ARRAY : GPU_TEXTURE_2D;
  if ((format_flag_ & (GPU_FORMAT_DEPTH_STENCIL | GPU_FORMAT_INTEGER)) == 0) {
    sampler_state = GPU_SAMPLER_FILTER;
  }
  return this->init_internal();
}

bool Texture::init_3D(int w, int h, int d, int mips, eGPUTextureFormat format)
{
  w_ = w;
  h_ = h;
  d_ = d;
  int mips_max = 1 + floorf(log2f(max_iii(w, h, d)));
  mipmaps_ = min_ii(mips, mips_max);
  format_ = format;
  format_flag_ = to_format_flag(format);
  type_ = GPU_TEXTURE_3D;
  if ((format_flag_ & (GPU_FORMAT_DEPTH_STENCIL | GPU_FORMAT_INTEGER)) == 0) {
    sampler_state = GPU_SAMPLER_FILTER;
  }
  return this->init_internal();
}

bool Texture::init_cubemap(int w, int layers, int mips, eGPUTextureFormat format)
{
  w_ = w;
  h_ = w;
  d_ = max_ii(1, layers) * 6;
  int mips_max = 1 + floorf(log2f(w));
  mipmaps_ = min_ii(mips, mips_max);
  format_ = format;
  format_flag_ = to_format_flag(format);
  type_ = (layers > 0) ? GPU_TEXTURE_CUBE_ARRAY : GPU_TEXTURE_CUBE;
  if ((format_flag_ & (GPU_FORMAT_DEPTH_STENCIL | GPU_FORMAT_INTEGER)) == 0) {
    sampler_state = GPU_SAMPLER_FILTER;
  }
  return this->init_internal();
}

bool Texture::init_buffer(GPUVertBuf *vbo, eGPUTextureFormat format)
{
  /* See to_texture_format(). */
  if (format == GPU_DEPTH_COMPONENT24) {
    return false;
  }
  w_ = GPU_vertbuf_get_vertex_len(vbo);
  h_ = 0;
  d_ = 0;
  format_ = format;
  format_flag_ = to_format_flag(format);
  type_ = GPU_TEXTURE_BUFFER;
  return this->init_internal(vbo);
}

bool Texture::init_view(const GPUTexture *src_,
                        eGPUTextureFormat format,
                        int mip_start,
                        int mip_len,
                        int layer_start,
                        int layer_len)
{
  const Texture *src = unwrap(src_);
  w_ = src->w_;
  h_ = src->h_;
  d_ = src->d_;
  switch (type_) {
    case GPU_TEXTURE_1D_ARRAY:
      h_ = layer_len;
      break;
    case GPU_TEXTURE_CUBE_ARRAY:
      BLI_assert(layer_len % 6 == 0);
      ATTR_FALLTHROUGH;
    case GPU_TEXTURE_2D_ARRAY:
      d_ = layer_len;
      break;
    default:
      BLI_assert(layer_len == 1 && layer_start == 0);
      break;
  }
  mip_start = min_ii(mip_start, src->mipmaps_ - 1);
  mip_len = min_ii(mip_len, (src->mipmaps_ - mip_start));
  mipmaps_ = mip_len;
  format_ = format;
  format_flag_ = to_format_flag(format);
  /* For now always copy the target. Target aliasing could be exposed later. */
  type_ = src->type_;
  sampler_state = src->sampler_state;
  return this->init_internal(src_, mip_start, layer_start);
}

/** \} */

/* -------------------------------------------------------------------- */
/** \name Operation
 * \{ */

void Texture::attach_to(FrameBuffer *fb, GPUAttachmentType type)
{
  for (int i = 0; i < ARRAY_SIZE(fb_); i++) {
    if (fb_[i] == nullptr) {
      fb_attachment_[i] = type;
      fb_[i] = fb;
      return;
    }
  }
  BLI_assert_msg(0, "GPU: Error: Texture: Not enough attachment");
}

void Texture::detach_from(FrameBuffer *fb)
{
  for (int i = 0; i < ARRAY_SIZE(fb_); i++) {
    if (fb_[i] == fb) {
      fb_[i]->attachment_remove(fb_attachment_[i]);
      fb_[i] = nullptr;
      return;
    }
  }
  BLI_assert_msg(0, "GPU: Error: Texture: Framebuffer is not attached");
}

void Texture::update(eGPUDataFormat format, const void *data)
{
  int mip = 0;
  int extent[3], offset[3] = {0, 0, 0};
  this->mip_size_get(mip, extent);
  this->update_sub(mip, offset, extent, format, data);
}

/** \} */

}  // namespace blender::gpu

/* -------------------------------------------------------------------- */
/** \name C-API
 * \{ */

using namespace blender;
using namespace blender::gpu;

/* ------ Memory Management ------ */

uint GPU_texture_memory_usage_get()
{
  /* TODO(fclem): Do that inside the new Texture class. */
  return 0;
}

/* ------ Creation ------ */

static inline GPUTexture *gpu_texture_create(const char *name,
                                             const int w,
                                             const int h,
                                             const int d,
                                             const eGPUTextureType type,
                                             int mips,
                                             eGPUTextureFormat tex_format,
                                             eGPUDataFormat data_format,
                                             const void *pixels)
{
  BLI_assert(mips > 0);
  Texture *tex = GPUBackend::get()->texture_alloc(name);
  bool success = false;
  switch (type) {
    case GPU_TEXTURE_1D:
    case GPU_TEXTURE_1D_ARRAY:
      success = tex->init_1D(w, h, mips, tex_format);
      break;
    case GPU_TEXTURE_2D:
    case GPU_TEXTURE_2D_ARRAY:
      success = tex->init_2D(w, h, d, mips, tex_format);
      break;
    case GPU_TEXTURE_3D:
      success = tex->init_3D(w, h, d, mips, tex_format);
      break;
    case GPU_TEXTURE_CUBE:
    case GPU_TEXTURE_CUBE_ARRAY:
      success = tex->init_cubemap(w, d, mips, tex_format);
      break;
    default:
      break;
  }

  if (!success) {
    delete tex;
    return nullptr;
  }
  if (pixels) {
    tex->update(data_format, pixels);
  }
  return reinterpret_cast<GPUTexture *>(tex);
}

GPUTexture *GPU_texture_create_1d(
    const char *name, int w, int mip_len, eGPUTextureFormat format, const float *data)
{
  return gpu_texture_create(name, w, 0, 0, GPU_TEXTURE_1D, mip_len, format, GPU_DATA_FLOAT, data);
}

GPUTexture *GPU_texture_create_1d_array(
    const char *name, int w, int h, int mip_len, eGPUTextureFormat format, const float *data)
{
  return gpu_texture_create(
      name, w, h, 0, GPU_TEXTURE_1D_ARRAY, mip_len, format, GPU_DATA_FLOAT, data);
}

GPUTexture *GPU_texture_create_2d(
    const char *name, int w, int h, int mip_len, eGPUTextureFormat format, const float *data)
{
  return gpu_texture_create(name, w, h, 0, GPU_TEXTURE_2D, mip_len, format, GPU_DATA_FLOAT, data);
}

GPUTexture *GPU_texture_create_2d_array(const char *name,
                                        int w,
                                        int h,
                                        int d,
                                        int mip_len,
                                        eGPUTextureFormat format,
                                        const float *data)
{
  return gpu_texture_create(
      name, w, h, d, GPU_TEXTURE_2D_ARRAY, mip_len, format, GPU_DATA_FLOAT, data);
}

GPUTexture *GPU_texture_create_3d(const char *name,
                                  int w,
                                  int h,
                                  int d,
                                  int mip_len,
                                  eGPUTextureFormat texture_format,
                                  eGPUDataFormat data_format,
                                  const void *data)
{
  return gpu_texture_create(
      name, w, h, d, GPU_TEXTURE_3D, mip_len, texture_format, data_format, data);
}

GPUTexture *GPU_texture_create_cube(
    const char *name, int w, int mip_len, eGPUTextureFormat format, const float *data)
{
  return gpu_texture_create(
      name, w, w, 0, GPU_TEXTURE_CUBE, mip_len, format, GPU_DATA_FLOAT, data);
}

GPUTexture *GPU_texture_create_cube_array(
    const char *name, int w, int d, int mip_len, eGPUTextureFormat format, const float *data)
{
  return gpu_texture_create(
      name, w, w, d, GPU_TEXTURE_CUBE_ARRAY, mip_len, format, GPU_DATA_FLOAT, data);
}

GPUTexture *GPU_texture_create_compressed_2d(
    const char *name, int w, int h, int miplen, eGPUTextureFormat tex_format, const void *data)
{
  Texture *tex = GPUBackend::get()->texture_alloc(name);
  bool success = tex->init_2D(w, h, 0, miplen, tex_format);

  if (!success) {
    delete tex;
    return nullptr;
  }
  if (data) {
    size_t ofs = 0;
    for (int mip = 0; mip < miplen; mip++) {
      int extent[3], offset[3] = {0, 0, 0};
      tex->mip_size_get(mip, extent);

      size_t size = ((extent[0] + 3) / 4) * ((extent[1] + 3) / 4) * to_block_size(tex_format);
      tex->update_sub(mip, offset, extent, to_data_format(tex_format), (uchar *)data + ofs);

      ofs += size;
    }
  }
  return reinterpret_cast<GPUTexture *>(tex);
}

GPUTexture *GPU_texture_create_from_vertbuf(const char *name, GPUVertBuf *vert)
{
  eGPUTextureFormat tex_format = to_texture_format(GPU_vertbuf_get_format(vert));
  Texture *tex = GPUBackend::get()->texture_alloc(name);

  bool success = tex->init_buffer(vert, tex_format);
  if (!success) {
    delete tex;
    return nullptr;
  }
  return reinterpret_cast<GPUTexture *>(tex);
}

GPUTexture *GPU_texture_create_error(int dimension, bool is_array)
{
  float pixel[4] = {1.0f, 0.0f, 1.0f, 1.0f};
  int w = 1;
  int h = (dimension < 2 && !is_array) ? 0 : 1;
  int d = (dimension < 3 && !is_array) ? 0 : 1;

  eGPUTextureType type = GPU_TEXTURE_3D;
  type = (dimension == 2) ? (is_array ? GPU_TEXTURE_2D_ARRAY : GPU_TEXTURE_2D) : type;
  type = (dimension == 1) ? (is_array ? GPU_TEXTURE_1D_ARRAY : GPU_TEXTURE_1D) : type;

  return gpu_texture_create("invalid_tex", w, h, d, type, 1, GPU_RGBA8, GPU_DATA_FLOAT, pixel);
}

GPUTexture *GPU_texture_create_view(const char *name,
                                    const GPUTexture *src,
                                    eGPUTextureFormat format,
                                    int mip_start,
                                    int mip_len,
                                    int layer_start,
                                    int layer_len)
{
  BLI_assert(mip_len > 0);
  BLI_assert(layer_len > 0);
  Texture *view = GPUBackend::get()->texture_alloc(name);
  view->init_view(src, format, mip_start, mip_len, layer_start, layer_len);
  return wrap(view);
}

/* ------ Update ------ */

void GPU_texture_update_mipmap(GPUTexture *tex_,
                               int miplvl,
                               eGPUDataFormat data_format,
                               const void *pixels)
{
  Texture *tex = reinterpret_cast<Texture *>(tex_);
  int extent[3] = {1, 1, 1}, offset[3] = {0, 0, 0};
  tex->mip_size_get(miplvl, extent);
  reinterpret_cast<Texture *>(tex)->update_sub(miplvl, offset, extent, data_format, pixels);
}

void GPU_texture_update_sub(GPUTexture *tex,
                            eGPUDataFormat data_format,
                            const void *pixels,
                            int offset_x,
                            int offset_y,
                            int offset_z,
                            int width,
                            int height,
                            int depth)
{
  int offset[3] = {offset_x, offset_y, offset_z};
  int extent[3] = {width, height, depth};
  reinterpret_cast<Texture *>(tex)->update_sub(0, offset, extent, data_format, pixels);
}

void *GPU_texture_read(GPUTexture *tex_, eGPUDataFormat data_format, int miplvl)
{
  Texture *tex = reinterpret_cast<Texture *>(tex_);
  return tex->read(miplvl, data_format);
}

void GPU_texture_clear(GPUTexture *tex, eGPUDataFormat data_format, const void *data)
{
  BLI_assert(data != nullptr); /* Do not accept NULL as parameter. */
  reinterpret_cast<Texture *>(tex)->clear(data_format, data);
}

void GPU_texture_update(GPUTexture *tex, eGPUDataFormat data_format, const void *data)
{
  reinterpret_cast<Texture *>(tex)->update(data_format, data);
}

void GPU_unpack_row_length_set(uint len)
{
  Context::get()->state_manager->texture_unpack_row_length_set(len);
}

/* ------ Binding ------ */

void GPU_texture_bind_ex(GPUTexture *tex_,
                         eGPUSamplerState state,
                         int unit,
                         const bool UNUSED(set_number))
{
  Texture *tex = reinterpret_cast<Texture *>(tex_);
  state = (state >= GPU_SAMPLER_MAX) ? tex->sampler_state : state;
  Context::get()->state_manager->texture_bind(tex, state, unit);
}

void GPU_texture_bind(GPUTexture *tex_, int unit)
{
  Texture *tex = reinterpret_cast<Texture *>(tex_);
  Context::get()->state_manager->texture_bind(tex, tex->sampler_state, unit);
}

void GPU_texture_unbind(GPUTexture *tex_)
{
  Texture *tex = reinterpret_cast<Texture *>(tex_);
  Context::get()->state_manager->texture_unbind(tex);
}

void GPU_texture_unbind_all()
{
  Context::get()->state_manager->texture_unbind_all();
}

void GPU_texture_image_bind(GPUTexture *tex, int unit)
{
  Context::get()->state_manager->image_bind(unwrap(tex), unit);
}

void GPU_texture_image_unbind(GPUTexture *tex)
{
  Context::get()->state_manager->image_unbind(unwrap(tex));
}

void GPU_texture_image_unbind_all()
{
  Context::get()->state_manager->image_unbind_all();
}

void GPU_texture_generate_mipmap(GPUTexture *tex)
{
  reinterpret_cast<Texture *>(tex)->generate_mipmap();
}

void GPU_texture_copy(GPUTexture *dst_, GPUTexture *src_)
{
  Texture *src = reinterpret_cast<Texture *>(src_);
  Texture *dst = reinterpret_cast<Texture *>(dst_);
  src->copy_to(dst);
}

void GPU_texture_compare_mode(GPUTexture *tex_, bool use_compare)
{
  Texture *tex = reinterpret_cast<Texture *>(tex_);
  /* Only depth formats does support compare mode. */
  BLI_assert(!(use_compare) || (tex->format_flag_get() & GPU_FORMAT_DEPTH));
  SET_FLAG_FROM_TEST(tex->sampler_state, use_compare, GPU_SAMPLER_COMPARE);
}

void GPU_texture_filter_mode(GPUTexture *tex_, bool use_filter)
{
  Texture *tex = reinterpret_cast<Texture *>(tex_);
  /* Stencil and integer format does not support filtering. */
  BLI_assert(!(use_filter) ||
             !(tex->format_flag_get() & (GPU_FORMAT_STENCIL | GPU_FORMAT_INTEGER)));
  SET_FLAG_FROM_TEST(tex->sampler_state, use_filter, GPU_SAMPLER_FILTER);
}

void GPU_texture_mipmap_mode(GPUTexture *tex_, bool use_mipmap, bool use_filter)
{
  Texture *tex = reinterpret_cast<Texture *>(tex_);
  /* Stencil and integer format does not support filtering. */
  BLI_assert(!(use_filter || use_mipmap) ||
             !(tex->format_flag_get() & (GPU_FORMAT_STENCIL | GPU_FORMAT_INTEGER)));
  SET_FLAG_FROM_TEST(tex->sampler_state, use_mipmap, GPU_SAMPLER_MIPMAP);
  SET_FLAG_FROM_TEST(tex->sampler_state, use_filter, GPU_SAMPLER_FILTER);
}

void GPU_texture_anisotropic_filter(GPUTexture *tex_, bool use_aniso)
{
  Texture *tex = reinterpret_cast<Texture *>(tex_);
  /* Stencil and integer format does not support filtering. */
  BLI_assert(!(use_aniso) ||
             !(tex->format_flag_get() & (GPU_FORMAT_STENCIL | GPU_FORMAT_INTEGER)));
  SET_FLAG_FROM_TEST(tex->sampler_state, use_aniso, GPU_SAMPLER_ANISO);
}

void GPU_texture_wrap_mode(GPUTexture *tex_, bool use_repeat, bool use_clamp)
{
  Texture *tex = reinterpret_cast<Texture *>(tex_);
  SET_FLAG_FROM_TEST(tex->sampler_state, use_repeat, GPU_SAMPLER_REPEAT);
  SET_FLAG_FROM_TEST(tex->sampler_state, !use_clamp, GPU_SAMPLER_CLAMP_BORDER);
}

void GPU_texture_swizzle_set(GPUTexture *tex, const char swizzle[4])
{
  reinterpret_cast<Texture *>(tex)->swizzle_set(swizzle);
}

void GPU_texture_free(GPUTexture *tex_)
{
  Texture *tex = reinterpret_cast<Texture *>(tex_);
  tex->refcount--;

  if (tex->refcount < 0) {
    fprintf(stderr, "GPUTexture: negative refcount\n");
  }

  if (tex->refcount == 0) {
    delete tex;
  }
}

void GPU_texture_ref(GPUTexture *tex)
{
  reinterpret_cast<Texture *>(tex)->refcount++;
}

int GPU_texture_dimensions(const GPUTexture *tex_)
{
  eGPUTextureType type = reinterpret_cast<const Texture *>(tex_)->type_get();
  if (type & GPU_TEXTURE_1D) {
    return 1;
  }
  else if (type & GPU_TEXTURE_2D) {
    return 2;
  }
  else if (type & GPU_TEXTURE_3D) {
    return 3;
  }
  else if (type & GPU_TEXTURE_CUBE) {
    return 2;
  }
  /* GPU_TEXTURE_BUFFER */
  return 1;
}

int GPU_texture_width(const GPUTexture *tex)
{
  return reinterpret_cast<const Texture *>(tex)->width_get();
}

int GPU_texture_height(const GPUTexture *tex)
{
  return reinterpret_cast<const Texture *>(tex)->height_get();
}

int GPU_texture_orig_width(const GPUTexture *tex)
{
  return reinterpret_cast<const Texture *>(tex)->src_w;
}

int GPU_texture_orig_height(const GPUTexture *tex)
{
  return reinterpret_cast<const Texture *>(tex)->src_h;
}

void GPU_texture_orig_size_set(GPUTexture *tex_, int w, int h)
{
  Texture *tex = reinterpret_cast<Texture *>(tex_);
  tex->src_w = w;
  tex->src_h = h;
}

eGPUTextureFormat GPU_texture_format(const GPUTexture *tex)
{
  return reinterpret_cast<const Texture *>(tex)->format_get();
}

bool GPU_texture_depth(const GPUTexture *tex)
{
  return (reinterpret_cast<const Texture *>(tex)->format_flag_get() & GPU_FORMAT_DEPTH) != 0;
}

bool GPU_texture_stencil(const GPUTexture *tex)
{
  return (reinterpret_cast<const Texture *>(tex)->format_flag_get() & GPU_FORMAT_STENCIL) != 0;
}

bool GPU_texture_integer(const GPUTexture *tex)
{
  return (reinterpret_cast<const Texture *>(tex)->format_flag_get() & GPU_FORMAT_INTEGER) != 0;
}

bool GPU_texture_cube(const GPUTexture *tex)
{
  return (reinterpret_cast<const Texture *>(tex)->type_get() & GPU_TEXTURE_CUBE) != 0;
}

bool GPU_texture_array(const GPUTexture *tex)
{
  return (reinterpret_cast<const Texture *>(tex)->type_get() & GPU_TEXTURE_ARRAY) != 0;
}

#ifndef GPU_NO_USE_PY_REFERENCES
void **GPU_texture_py_reference_get(GPUTexture *tex)
{
  return unwrap(tex)->py_ref;
}

void GPU_texture_py_reference_set(GPUTexture *tex, void **py_ref)
{
  BLI_assert(py_ref == nullptr || unwrap(tex)->py_ref == nullptr);
  unwrap(tex)->py_ref = py_ref;
}
#endif

/* TODO: remove. */
int GPU_texture_opengl_bindcode(const GPUTexture *tex)
{
  return reinterpret_cast<const Texture *>(tex)->gl_bindcode_get();
}

void GPU_texture_get_mipmap_size(GPUTexture *tex, int lvl, int *r_size)
{
  return reinterpret_cast<Texture *>(tex)->mip_size_get(lvl, r_size);
}

/** \} */

/* -------------------------------------------------------------------- */
/** \name GPU Sampler Objects
 *
 * Simple wrapper around opengl sampler objects.
 * Override texture sampler state for one sampler unit only.
 * \{ */

void GPU_samplers_update()
{
  GPUBackend::get()->samplers_update();
}

/** \} */

/* -------------------------------------------------------------------- */
/** \name GPU texture utilities
 * \{ */

size_t GPU_texture_component_len(eGPUTextureFormat tex_format)
{
  return to_component_len(tex_format);
}

size_t GPU_texture_dataformat_size(eGPUDataFormat data_format)
{
  return to_bytesize(data_format);
}

/** \} */