Home made diving torch

Hi, Please forgive me as I am a newbie, i also have limited electronics
experience.

I hope anyone will be able to help me??
I have built myself a diving torch, The design is an umibilical system,
there are no external switches. To turn the torch on the handle rotates
which operates a reed switch which is place internally. This is
connected to a relay which turns on the lamp.

I would like to improve this with a self monitoring circuit which will
dim the light by 50% when the battery voltage reaches 50% of the
operating voltage.(Hope that makes sense??).
I would also like the lamp to flash (approx 5 - 6 times) when the
voltage of the battery reaches the minimal voltage allowable(As
specified by the manufacture) then it switches off until the batteries
are fully charged.
Attached to the circuit I would like to have a push button to determine
the battery status when the case is open, ideally via 3 off leds??
Green - Good
Amber - Medium
Red - Low

Here are the details of the torch:-

Batteries - 2 x 12V 3.2Ahr seal Lead acid
Lamp - Halogen 12V 75W
Reed switch in the umbilical torch

Regards

Simian_196

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