AIDs/HIV Chained Distribution

turtles-own
[
  infected?           ;; if true, the person is infectious
  resistant?          ;; if true, the person can't be infected
  virus-check-timer   ;; number of ticks since this person's last virus-check
]

to make-movie

  user-message "First, save your new movie file (choose a name ending with .mov)"
  let path user-new-file
  if not is-string? path [ stop ]  ;; stop if user canceled

  setup
  movie-start path
  movie-grab-view
  while [ count turtles < 2000 ]
    [ go
      movie-grab-view ]

  ;; export the movie
  movie-close
  user-message (word "Exported movie to " path)
end 

to setup
  __clear-all-and-reset-ticks
  setup-nodes
  setup-spatially-clustered-network
  ask n-of initial-outbreak-size turtles
    [ become-infected ]
  ask links [ set color white ]
  update-plot
end 

to setup-nodes
  set-default-shape turtles "square"
  crt number-of-people
  [
    setxy (random-xcor * 0.9) (random-ycor * 0.9)
    become-susceptible
    set virus-check-timer random virus-check-frequency
  ]
end 

to setup-spatially-clustered-network
  let num-links (average-node-degree * number-of-people) / 2
  while [count links < num-links ]
  [
    ask one-of turtles
    [
      let choice (min-one-of (other turtles with [not link-neighbor? myself])
                   [distance myself])
      if choice != nobody [ create-link-with choice ]
    ]
  ]
  ; make the network look a little prettier
  repeat 10
  [
    layout-spring turtles links 0.3 (world-width / (sqrt number-of-people)) 1
  ]
end 

to go
  if all? turtles [not infected?]
    [ stop ]
  ask turtles
  [
     set virus-check-timer virus-check-timer + 1
     if virus-check-timer >= virus-check-frequency
       [ set virus-check-timer 0 ]
  ]
  spread-virus
  do-virus-checks
  tick
  update-plot
end 

to become-infected  ;; turtle procedure
  set infected? true
  set resistant? false
  set color yellow
end 

to become-susceptible  
  set infected? false
  set resistant? false
  set color green
end 

to become-aids 
  set infected? false
  set resistant? true
  set color red
  ask my-links [ set color gray - 2 ]
end 

to spread-virus
  ask turtles with [infected?]
    [ ask link-neighbors with [not resistant?]
        [ if random-float 100 < virus-spread-chance
            [ become-infected ] ] ]
end 

to do-virus-checks
  ask turtles with [infected? and virus-check-timer = 0]
  [
    if random 100 < recovery-chance
    [
      ifelse random 100 < gain-resistance-chance
        [ become-aids ]
        [ become-susceptible ]
    ]
  ]
end 

to update-plot
  set-current-plot "HIV+ Status"
  set-current-plot-pen "Condom Usage"
  plot (count turtles with [not infected? and not resistant?]) / (count turtles) * 100
  set-current-plot-pen "HIV+ Infected"
  plot (count turtles with [infected?]) / (count turtles) * 100
  set-current-plot-pen "AIDS / Mature"
  plot (count turtles with [resistant?]) / (count turtles) * 100
  set-current-plot "Usage"
  plot (count turtles with [not infected? and not resistant?])
  set-current-plot "HIV+"
  plot (count turtles with [infected?])
  
  plot 1
end