Atmel ATmega328 with WIFI

I am trying to build a board with Atmel ATmega328 as micro controller and wifi module to communicate with pc, with two push button, and with one led.

What I want to achieve the system should be sleep mode always untill any of Button pressed and then send massage using UPD and go back to sleep mode.

Can you help me with wifi module (Desing) and how can we put this in sleep mode.

Notice: this system should last at least 1 month with single 3v battery (voltage can be chaged)

Suggest you forget it, just use an ESP8266 - you do not need the Arduino then.

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