from vnet_blocks import *

class VNetLight(BaseModel):
    """
    A lighter version of Vnet that skips down_tr256 and up_tr256 in oreder to reduce time and space complexity
    """
    def __init__(self, elu=True, in_channels=1, classes=4):
        super(VNetLight, self).__init__()
        self.classes = classes
        self.in_channels = in_channels

        self.in_tr = InputTransition(in_channels, elu)
        self.down_tr32 = DownTransition(16, 1, elu)
        self.down_tr64 = DownTransition(32, 2, elu)
        self.down_tr128 = DownTransition(64, 3, elu, dropout=True)
        self.up_tr128 = UpTransition(128, 128, 2, elu, dropout=True)
        self.up_tr64 = UpTransition(128, 64, 1, elu)
        self.up_tr32 = UpTransition(64, 32, 1, elu)
        self.out_tr = OutputTransition(32, classes, elu)

    def forward(self, x):
        out16 = self.in_tr(x)
        out32 = self.down_tr32(out16)
        out64 = self.down_tr64(out32)
        out128 = self.down_tr128(out64)
        out = self.up_tr128(out128, out64)
        out = self.up_tr64(out, out32)
        out = self.up_tr32(out, out16)
        out = self.out_tr(out)
        return out

    def test(self,device='cpu'):
        input_tensor = torch.rand(1, self.in_channels, 32, 32, 32)
        ideal_out = torch.rand(1, self.classes, 32, 32, 32)
        out = self.forward(input_tensor)
        assert ideal_out.shape == out.shape
        summary(self.to(torch.device(device)), (self.in_channels, 32, 32, 32),device=device)
        print("Vnet Light test is complete")