#include "Render/DeviceContext/DCBitmap.h"
#include "Render/Textures/BitmapPixels.h"
#include "Render/Textures/BitmapTextureCache.h"
#include "Render/RenderSystemBase.h"
#include "Render/Textures/Texture.h"
#include "Render/Textures/TextureCache.h"

#include <algorithm>

// INLINED
BitmapTextureCache::BitmapTextureCache() : m_alpha(false) {
}

// INLINED
BitmapTextureCache::~BitmapTextureCache() {
  this->Clear();
}

// OFFSET: 0x00548380
// FUNCTION: fn_01854
void CDCBitmap::UpdateCache() {
  if (!this->m_bitmap.dirty) {
    return;
  }

  if (this->m_cache.m_alpha == true) {
    if (this->m_cache.m_textures.empty()) {
      CTexture* texture = g_texMgr.CreateTexture(this->m_bitmap.width, this->m_bitmap.height, TextureFormat::A8R8G8B8, false, false);
      if (texture) {
        this->m_cache.m_textures.push_back(texture);
      }
    }

    for (CTexture* texture : this->m_cache.m_textures) {
      texture->Upload(0, 0, this->m_bitmap.width, this->m_bitmap.height, this->m_bitmap.pixels, 0, this->m_bitmap.width);
    }
  } else {
    if (this->m_cache.m_textures.empty()) {
      for (unsigned y = 0; y < this->m_bitmap.height; y += 256) {
        for (unsigned x = 0; x < this->m_bitmap.width; x += 256) {
          this->m_cache.m_textures.push_back(
            g_texMgr.CreateTexture(std::min(256u, this->m_bitmap.width - x), std::min(256u, this->m_bitmap.height - y), TextureFormat::A1R5G5B5, false, false)
          );
        }
      }
    }

    const std::int32_t bytes = static_cast<std::int32_t>(4u * this->m_bitmap.width * this->m_bitmap.height);

    for (std::int32_t offset = 0; offset < bytes; offset += 4) {
      reinterpret_cast<unsigned char*>(this->m_bitmap.pixels)[offset + 3] = 255;
    }

    auto texture = this->m_cache.m_textures.begin();

    for (unsigned y = 0; y < this->m_bitmap.height; y += 256) {
      for (unsigned x = 0; x < this->m_bitmap.width; x += 256) {
        (*texture)->Upload(0, 0, std::min(256u, this->m_bitmap.width - x), std::min(256u, this->m_bitmap.height - y), this->m_bitmap.pixels + x + y * this->m_bitmap.width, 0, this->m_bitmap.width);
        ++texture;
      }
    }
  }

  this->m_bitmap.dirty = false;
}

// OFFSET: 0x00547B80
// FUNCTION: fn_01846
void CDCBitmap::Draw(int x, int y, int width, int height, std::uint32_t color) {
  if (!this->m_bitmap.pixels) {
    return;
  }

  this->UpdateCache();
  if (this->m_cache.m_textures.empty()) {
    return;
  }

  if (this->m_cache.m_alpha == true) {
    for (auto texture = this->m_cache.m_textures.begin(); texture != this->m_cache.m_textures.end(); ++texture) {
      (*texture)->Draw(x, y, width, height, color);
    }
  } else {
    auto texture = this->m_cache.m_textures.begin();
    int remainingHeight = height;

    for (int row = 0; row < height; row += 256, remainingHeight -= 256) {
      int remainingWidth = width;

      for (int column = 0; column < width; column += 256, remainingWidth -= 256) {
        (*texture)->Draw(x + column, y + row, remainingWidth > 256 ? 256 : remainingWidth, remainingHeight > 256 ? 256 : remainingHeight, color);
        ++texture;
      }
    }
  }
}