local function load_nn()
   require 'torch'
   require 'nn'
end
local function load_cunn()
   require 'cutorch'
   require 'cunn'
end
local function load_cudnn()
   cudnn = require('cudnn')
end
local function make_data_parallel_table(model, gpus)
   if cudnn then
      local fastest, benchmark = cudnn.fastest, cudnn.benchmark
      local dpt = nn.DataParallelTable(1, true, true)
	 :add(model, gpus)
	 :threads(function()
	       require 'pl'
	       local __FILE__ = (function() return string.gsub(debug.getinfo(2, 'S').source, "^@", "") end)()
	       package.path = path.join(path.dirname(__FILE__), "..", "lib", "?.lua;") .. package.path
	       require 'torch'
	       require 'cunn'
	       require 'w2nn'
	       local cudnn = require 'cudnn'
	       cudnn.fastest, cudnn.benchmark = fastest, benchmark
		 end)
      dpt.gradInput = nil
      model = dpt:cuda()
   else
      local dpt = nn.DataParallelTable(1, true, true)
	    :add(model, gpus)
	 :threads(function()
	       require 'pl'
	       local __FILE__ = (function() return string.gsub(debug.getinfo(2, 'S').source, "^@", "") end)()
	       package.path = path.join(path.dirname(__FILE__), "..", "lib", "?.lua;") .. package.path
	       require 'torch'
	       require 'cunn'
	       require 'w2nn'
		 end)
      dpt.gradInput = nil
      model = dpt:cuda()
   end
   return model
end

if w2nn then
   return w2nn
else
   w2nn = {}
   local state, ret = pcall(load_cunn)
   if not state then
      error("Failed to load CUDA modules. Please check the CUDA Settings.\n---\n" .. ret)
   end
   pcall(load_cudnn)

   function w2nn.load_model(model_path, force_cudnn, mode)
      mode = mode or "ascii"
      local model = torch.load(model_path, mode)
      if force_cudnn then
	 model = cudnn.convert(model, cudnn)
      end
      model:cuda():evaluate()
      return model
   end
   function w2nn.data_parallel(model, gpus)
      if #gpus > 1 then
	 return make_data_parallel_table(model, gpus)
      else
	 return model
      end
   end
   require 'LeakyReLU'
   require 'ClippedWeightedHuberCriterion'
   require 'ClippedMSECriterion'
   require 'SSIMCriterion'
   require 'InplaceClip01'
   require 'L1Criterion'
   require 'ShakeShakeTable'
   require 'PrintTable'
   require 'Print'
   require 'AuxiliaryLossTable'
   require 'AuxiliaryLossCriterion'
   return w2nn
end