Color Coding and legends in Matrix visual

Hi All,

I need some help on Matrix visual. I am creating a tracking calendar type visual where weekdays and date are in columns. A value exists for four days, so the four cells on the corresponding date in matrix will be of same color. If another value exists for 10 days then 10 cellson the corresponding date in matrix will be of same color. FYI, there is no fixed number of days of duration of the value.

Eagerly looking for help. Thank you !