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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.
Not staying hydrated with enough water during the day may be one of the big causes of leg cramps at night. This is most likely due to fluid imbalances of electrolytes (mainly sodium, potassium, calcium, and magnesium). Overuse of the muscles, perhaps from exercising, gardening or other physical activities.