( todo: Set treads to turn relative to tank position, not turret position. It    )
(       works okay now since the treads help turn the turret faster, but I think )
(       it could be better.                                                      )
( sensors:                                                                       )
(   0: firing sensor                                                             )
(   1: fore collision sensor                                                     )
(   2: starboard fore long-range turret-mounted sensor                           )
(   3: fore short-range sensor                                                   )
(   4: port fore long-range turret-mounted sensor                                )
(   5: starboard mid-range turrent-mounted sensor                                )
(   6: port mid-range turrent-mounted sensor                                     )
(   7: fore long-range turret-mounted sensor                                     )
(   8: starboard long-range turret-mounted sensor                                )
(   9: port long-range turret-mounted sensor                                     )

fire-ready? { 1 set-led! }                    ( Turn on led if cannon is ready.  )
  { 0 set-led!
  3 sensor? { -100 -100 set-speed! } if
  } ifelse
  
0 sensor? { fire! } if

1 sensor? { -100 -100 set-speed! }
{
7 sensor?                                     ( If there is an enemy dead ahead  )
  { fire-ready?                               ( and the cannon is ready, speed   )
    { 0 sensor? { fire! }                     ( up to catch it and fire when in  )
      { 1 sensor? { }                         ( range. if cannon is not ready,   )
        { 100 100 set-speed! } ifelse         ( pursue at a safe distance. if    )
      } ifelse                                ( the enemy gets too close, back   )
    }                                         ( off.                             )
    { 1 sensor? { }
      { 3 sensor? { -100 -100 set-speed! }
        { 100 100 set-speed! } ifelse
      } ifelse
    } ifelse
  }
  { 8 sensor?                                 ( If there is an enemy on right,   )
    { 6 sensor?                               ( turn right, but if there is a    )
      { get-turret 20 - set-turret!           ( closer enemy on left, turn left. )
      1 sensor? { }                           ( To avoid collisions, flee if an  )
        { 3 sensor? { -100 -80 set-speed! }   ( an enemy gets too close.         )
          { -100 100 set-speed! } ifelse      
        } ifelse
      }                                         
      { 2 sensor?
        { get-turret 5 + set-turret! 100 50 set-speed! }
        { get-turret 20 + set-turret! 100 -100 set-speed! } ifelse
      } ifelse
    }
	{ 9 sensor?                               ( If there is an enemy on left,    )
	  { 5 sensor?                             ( turn left, but if there is a     )
		{ get-turret 20 + set-turret!         ( closer enemy on right, turn      )
		1 sensor? { }                         ( right. To avoid collisions, flee )
		  { 3 sensor? { -80 -100 set-speed! } ( if an enemy gets too close.      )
		    { 100 -100 set-speed! } ifelse    
		  } ifelse
		}                                         
		{ 4 sensor?
		  { get-turret 5 - set-turret! 50 100 set-speed! }
		  { get-turret 20 - set-turret! -100 100 set-speed! } ifelse
		} ifelse
	  }
	  { 100 100 set-speed! 0 set-turret! } ifelse ( if there are no nearby tanks,  )
    } ifelse                                    ( maintain cruising speed and    )
  } ifelse                                      ( reset turret to face forward.  )
} ifelse