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According to the Mayo Clinic these are some known causes of leg cramps. As you can see alcoholism and dehydration are listed. I doubt that a couple of glasses of wine will cause them, but drinking water right before going to bed may help.
For many people, however, leg cramps occur at night while they sleep and not while engaged in sports. Such cramps may be caused by dehydration (which can be associated with diarrhea, insufficient fluid intake, excessive sweating), a deficiency of calcium, potassium, and/or magnesium, or for reasons unknown.