import theano, numpy
import theano.tensor as T
import theano.tests.unittest_tools as utt

# Skip test if cuda_ndarray is not available.
from nose.plugins.skip import SkipTest
import theano.sandbox.cuda as cuda
if cuda.cuda_available == False:
    raise SkipTest('Optional package cuda disabled')

if theano.config.mode=='FAST_COMPILE':
    mode_with_gpu = theano.compile.mode.get_mode('FAST_RUN').including('gpu')
    mode_without_gpu = theano.compile.mode.get_mode('FAST_RUN').excluding('gpu')
else:
    mode_with_gpu = theano.compile.mode.get_default_mode().including('gpu')
    mode_without_gpu = theano.compile.mode.get_default_mode().excluding('gpu')

def test_GpuCrossentropySoftmaxArgmax1HotWithBias():
    """
    This is basic test for GpuCrossentropySoftmaxArgmax1HotWithBias

    We check that we loop when their is too much threads
    TODO: check that we loop when their is too much block(>32*1024)

    """

    n_in = 1000
    batch_size = 4097
    n_out = 1250

    if theano.config.mode!="DEBUG_MODE":
        n_in = 4098
        n_out = 4099

    x = T.fmatrix('x')
    y = T.lvector('y')


    b = T.fvector('b')
    #W = T.fmatrix('W')

    #we precompute the dot with big shape before to allow the test of GpuCrossentropySoftmax1HotWithBiasDx to don't fail with the error (the launch timed out and was terminated) on GPU card not powerfull enought. We need the big shape to check for corner case.
    dot_result = T.fmatrix('dot_result')

    # Seed numpy.random with config.unittests.rseed
    utt.seed_rng()

    xx = numpy.asarray(numpy.random.rand(batch_size,n_in),dtype=numpy.float32)
    #?????yy = numpy.ones((batch_size,),dtype='float32')
    yy = numpy.ones((batch_size,),dtype='int32')
    b_values = numpy.zeros((n_out,),dtype='float32')
    W_values = numpy.asarray(numpy.random.rand(n_in,n_out),dtype='float32')

    dot_value = numpy.asarray(numpy.dot(xx, W_values),dtype='float32')
    del W_values
    p_y_given_x = T.nnet.softmax(dot_result+b)
    y_pred = T.argmax(p_y_given_x, axis=-1)
    loss = -T.mean(T.log(p_y_given_x)[T.arange(y.shape[0]), y])
    dW = T.grad(loss, dot_result)
    classify = theano.function( inputs = [x,y,b,dot_result], outputs = [loss,y_pred,dW],
                                mode = mode_without_gpu)
    classify_gpu = theano.function( inputs = [x,y,b,dot_result], outputs = [loss,y_pred,dW],
                                    mode = mode_with_gpu)
    #theano.printing.debugprint(classify)
    #theano.printing.debugprint(classify_gpu)

    assert any([isinstance(node.op,T.nnet.CrossentropySoftmaxArgmax1HotWithBias) for node in classify.maker.env.toposort()])
    assert any([isinstance(node.op,cuda.nnet.GpuCrossentropySoftmaxArgmax1HotWithBias) for node in classify_gpu.maker.env.toposort()])

    out=classify(xx,yy,b_values,dot_value)
    gout=classify_gpu(xx,yy,b_values,dot_value)

    assert len(out)==len(gout)==3
    assert numpy.allclose(out[0],gout[0])
    assert numpy.allclose(out[2],gout[2],atol=3e-6),numpy.absolute(gout-out).max()
    assert numpy.allclose(out[1],gout[1]),[(id,out[1][id],gout[1][id],val) for id,val in enumerate(out[1]-gout[1]) if val!=0]

def test_GpuCrossentropySoftmax1HotWithBiasDx():
    """
    This is basic test for GpuCrossentropySoftmax1HotWithBiasDx

    We check that we loop when their is too much threads
    TODO: check that we loop when their is too much block(>32*1024)

    """
    n_in = 1000
    batch_size = 4097
    n_out = 1250

    # Seed numpy.random with config.unittests.rseed
    utt.seed_rng()

    softmax_output_value = numpy.random.rand(batch_size, n_out).astype('float32')
    dnll_value = numpy.asarray(numpy.random.rand(batch_size),dtype='float32')
    y_idx_value = numpy.random.randint(low=0, high=5, size=batch_size)

    softmax_output = T.fmatrix()
    softmax_output /= softmax_output.sum(axis=1).reshape(softmax_output.shape[1],1)
    op = theano.tensor.nnet.crossentropy_softmax_1hot_with_bias_dx(
        dnll_value,
        softmax_output,
        y_idx_value)

    cpu_f = theano.function([softmax_output],op,mode = mode_without_gpu)
    gpu_f = theano.function([softmax_output],op,mode = mode_with_gpu)
    #theano.printing.debugprint(cpu_f)
    #theano.printing.debugprint(gpu_f)

    assert any([isinstance(node.op,T.nnet.CrossentropySoftmax1HotWithBiasDx) for node in cpu_f.maker.env.toposort()])
    assert any([isinstance(node.op,cuda.nnet.GpuCrossentropySoftmax1HotWithBiasDx) for node in gpu_f.maker.env.toposort()])

    cpu_out = cpu_f(softmax_output_value)
    gpu_out = gpu_f(softmax_output_value)

    rtol = 1e-5
    atol = 1e-6
    if not numpy.allclose(cpu_out, gpu_out, rtol=rtol, atol=atol):
        abs_err, rel_err = T.numeric_grad.abs_rel_err(cpu_out, gpu_out)
        scaled_err = numpy.minimum(abs_err/atol, rel_err/rtol)
        max_i = scaled_err.argmax()

        print 'max err index:', max_i, max_i / batch_size, max_i % batch_size, max_i / n_out, max_i & n_out
        print 'At that index:'
        print 'err:', scaled_err.flatten()[max_i]
        print 'absolute error:', abs_err.flatten()[max_i]
        print 'relative error:', rel_err.flatten()[max_i]
        print 'cpu_out:', cpu_out.flatten()[max_i]
        print 'gpu_out:', gpu_out.flatten()[max_i]
        print 'softmax_output_value:', softmax_output_value.flatten()[max_i]
        print 'dnll_value:', dnll_value[max_i / n_out]
        print 'y_idx_value:', y_idx_value[max_i / n_out]

        assert False, "numpy.allclose(cpu_out, gpu_out, rtol=%s, atol=%s)" % (
                rtol, atol)


def test_softmax_with_bias():
    """
    This is basic test for GpuSoftmaxWithBias

    We check that we loop when their is too much block
    TODO: check that we loop when their is too much thread.(THIS IS NOT IMPLEMENTED)
    """
    x = T.fmatrix('x')

    #we need to test n>32*1024 to check that we make the block loop.
    n,m=2<<15,5

    data = numpy.arange(n*m, dtype='float32').reshape(n,m)

    z = T.nnet.softmax_with_bias(x, T.zeros_like(x[0,:]))

    f = theano.function([x],z, mode=mode_without_gpu)
    f_gpu = theano.function([x],z, mode=mode_with_gpu)
    assert f.maker.env.toposort()[-1].op==T.nnet.softmax_with_bias
    assert isinstance(f_gpu.maker.env.toposort()[-2].op,cuda.nnet.GpuSoftmaxWithBias)

    out=f(data)
    gout=f_gpu(data)
    assert numpy.allclose(out,gout),numpy.absolute(out-gout)

def test_softmax():
    """
    This is basic test for GpuSoftmax

    We check that we loop when their is too much block
    TODO: check that we loop when their is too much thread.(THIS IS NOT IMPLEMENTED)
    """
    x = T.fmatrix('x')

    #we need to test n>32*1024 to check that we make the block loop.
    n,m=2<<15,5

    data = numpy.arange(n*m, dtype='float32').reshape(n,m)

    z = T.nnet.softmax(x)

    f = theano.function([x],z, mode=mode_without_gpu)
    f_gpu = theano.function([x],z, mode=mode_with_gpu)
    assert f.maker.env.toposort()[-1].op==T.nnet.softmax
    assert isinstance(f_gpu.maker.env.toposort()[-2].op,cuda.nnet.GpuSoftmax)

    out=f(data)
    gout=f_gpu(data)
    assert numpy.allclose(out,gout),numpy.absolute(out-gout)
