Socio-Natural Model

globals [ grass
   gini-index-reserve
  lorenz-points ]

breed [ apersons aperson ]
breed [ bpersons bperson ]

patches-own [ grass-amount ]

turtles-own [
  resource ;; the amount of resource this person has
  age ;; the current age of this person (in ticks)
  max-age ;; the age at which this person will die of natural causes

]

to setup
  clear-all
  create-apersons apersons-initial-population [ setup-apersons ]
  create-bpersons bpersons-initial-population [ setup-bpersons ]
  ask patches [
    set grass-amount random-float 10.0 ;; each patch starts with a random amount of grass
    recolor-grass ] ;; color it shades of green
  set grass count patches with [ grass-amount > 0 ]
  update-lorenz-and-gini

  reset-ticks
end 

to go
  if not any? turtles [ stop ]
  ask turtles [
   move
   harvest
   if resource >= 5
     [ share ] ;; share with a number of neighbors
   reproduce
   set age age + 1
   if resource < 0 or age > max-age
    [die]
    ]
 regrow-grass
 set grass count patches with [ grass-amount > 0 ]
 update-lorenz-and-gini
 tick
end 


;;-----------------
;; TURTLE UPDATES
;;-----------------

to setup-apersons ;; apersons procedure
  set color magenta  ;; how to color? Shades of a color?
  set shape "person"
  set size 1.25;; easier to see
  setxy random-xcor random-ycor ;;population- what other ways to do this?? where do I want my persons to be?
  set age 0
  set max-age random-float 100
  set resource 10
end 

to setup-bpersons ;; bpersons procedure
  set color orange
  set shape "person"
  set size 1.25;; easier to see
  setxy random-xcor random-ycor ;;population- what other ways to do this?? where do I want my persons to be?
  set age 0
  set max-age random-float 100
  set resource 10
end 

;;---------------
;; GO PROCEDURES
;;---------------

to move ;; how to model migration with vision (high vision for migrators/lower for non?);; make quadrants with different growback rates for seasons?
  ifelse breed = apersons
  [ move-apersons ][
  if breed = bpersons
  [ move-bpersons ] ]
end 

to move-apersons
    let target max-one-of patches [ grass-amount ]
    face target
    move-to target
    set resource resource - 1
end 

to move-bpersons
   let target max-one-of neighbors4 [ grass-amount ]
    face target
    move-to target
    set resource resource - 1
end 
;;set vision (patches with [ grass-amount > .25
  ;;     ] in-radius bperson-vision)

to harvest
  ifelse breed = apersons
   [ harvest-apersons
] [
   if breed = bpersons
   [ harvest-bpersons
] ]
end 

to harvest-apersons  ;; eat-cooperative from cooperation model and GL
  if grass-amount > 5
  [ let harvest-amount grass-amount * 0.50
    set grass-amount grass-amount - harvest-amount
    set resource resource + harvest-amount ]
   recolor-grass
end 

to harvest-bpersons  ;; eat-greedy from cooperation model and GL
  if grass-amount > 0 [
    let harvest-amount grass-amount * 1
    set grass-amount grass-amount - harvest-amount
    set resource resource + harvest-amount ]
   recolor-grass
end 

to share
 ifelse breed = apersons [ share-apersons ]
[ if breed = bpersons [ share-bpersons ]
]
end 

to share-apersons ;;modified from diffusion on a directed network model
   let recipients apersons in-radius 3 ;; larger radius to suggest more egalitarian, but what if no one from breed in radius? directed link network a better guarantee
   if any? recipients [ ask recipients [ set resource resource + ( apersons-share-amount / count recipients ) ] ]
   set resource resource - apersons-share-amount
end 

to share-bpersons ;; modified from diffusion on a directed network model
   let recipients bpersons in-radius 1
   if any? recipients [ ask recipients [ set resource resource + ( bpersons-share-amount / count recipients ) ] ]
   set resource resource - bpersons-share-amount
end 

to reproduce;;certain age and amount of resource range needed for reproduction; also add sex and neighbor component?
  ifelse breed = apersons [ reproduce-apersons ]
  [ if breed = bpersons [ reproduce-bpersons ]
  ]
end 

to reproduce-apersons ;; must modify reproduction - look at % reproduction in wolf sheep predation model
   if age >= 15 and age <= 40 ;; and last_reproduced < current_tick - 4
     [ hatch random (apersons-number-offspring) [
      setup-apersons ] set resource resource / apersons-number-offspring]
end 

to reproduce-bpersons
  if age >= 15 and age <= 40;; and (last_reproduced < current_tick - 4
       [ hatch random (bpersons-number-offspring) [
      setup-bpersons ] set resource resource / bpersons-number-offspring]
end 
;;-------------------
;; PATCH UPDATES
;;-------------------

to regrow-grass
  ask patches [
    set grass-amount grass-amount + 0.01
    if grass-amount > 10 [
      set grass-amount 10
    ]
recolor-grass
  ]
end 

to recolor-grass
  set pcolor scale-color green grass-amount 0 20
end 


;;-------------------------------------
;; MONITORING AND REPORTING PROCEDURES
;;-------------------------------------

to-report resource-fraction ;; GL, feeding example. the math
  let possible-resource (count patches) * 10
  let total-resource sum [ grass-amount ] of patches
  report total-resource / possible-resource
end 

to update-lorenz-and-gini
  let num-people count turtles
  let sorted-wealths sort [resource] of turtles
  let total-wealth sum sorted-wealths
  let wealth-sum-so-far 0
  let index 0
  set gini-index-reserve 0
  set lorenz-points []
  repeat num-people [
    set wealth-sum-so-far (wealth-sum-so-far + item index sorted-wealths)
    set lorenz-points lput ((wealth-sum-so-far / total-wealth) * 100) lorenz-points
    set index (index + 1)
    set gini-index-reserve
      gini-index-reserve +
      (index / num-people) -
      (wealth-sum-so-far / total-wealth)
  ]
end