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Automatic turn on off for lights

Using electronic circuit diagram below can be designed a device which turn on and off the light in several rooms in random order. This electronic circuit in same time with decreasing of ambient light will turn on light and leave it on for 1… 5 hours .
The circuit can be used to create the impression that there are staff in the building which is attached (useful when you are away on vacation) or to automatically turn on the light in different rooms.
When the light intensity decreases photoresist (LDR) B1 output gate causing increases in state N6 pass logic "0" (since that can be adjusted with P1). Reset input (pin 12) to counter IC1 is therefore all "0" logic, and IC1 begins to count. Counter contains an internal clock generator whose frequency is determined by capacitor C2 and resistance R4 potentiometer P2.
Once the numbers start IC1's output N5 will be "1" logic, but out of N7 and therefore the transistor T1 will remain unaffected until the N8 will appear a logical "1". Together with gates N1 ... N4, N8 and N9 forms a pseudo generator which, through the gate N7, control transistor Q1 and turn off lights and building
After a certain period of time (one to five hours), exit 14 of IC1 returns to logic "1" through diode D1 making to stop the internal oscillator clock will keep Q14 in "1" logic. Now, the gate N7 is inhibited so that the building lights are extinguished.

Circuit Diagram: 
Automatic turn on off for lights circuit

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