Lombricompostera

breed [ worms a-worms ]

turtles-own [energy]

to setup
  clear-all
  setup-patches
  setup-turtles
  reset-ticks
end 

to setup-patches
  ask patches [ set pcolor green ]
end 

to setup-turtles
  create-turtles worms-number
  [
    set shape "circle"
    set color red
    set size 0.5
    setxy random-xcor random-ycor
  ]
end 

to go
  if ticks >= 150 [ stop ]
  move-turtles
  eat-grass
  reproduce
  check-death
  regrow-grass
  tick
end 

to move-turtles
  ask turtles [ right random 360 forward 1 set energy energy - 1 ]
end 

to eat-grass
  ask turtles [ if pcolor = green [ set pcolor brown set energy (energy + energy-from-compost) ] ifelse show-energy? [ set label energy ] [ set label "" ] ]
end 

to reproduce
  ask turtles [ if energy > birth-energy [ set energy energy - birth-energy hatch 1 [ set energy birth-energy ] ] ]
end 

to check-death
  ask turtles [ if energy <= 0 [ die ] ]
end 

to regrow-grass
  ask patches [if random 100 < compost-refilling-rate [ set pcolor green ] ]
end