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;;; DECLARATIONS
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breed [ people person ]   ;; use people instead of turtles

globals [

  ;Counters and statistics for person-to-person conversations (internal influence)
  contacts                ;; number of contacts made with other individuals
  old-contacts            ;; previous total
  contacts-per-time       ;; how many contacts made this time period
  conversation-starts     ;; total number of conversations
  old-conversation-starts ;; previous total
  starts-per-time         ;; how many conversations made this time period - number ended
  conversation-ends       ;; total number ended
  old-conversation-ends   ;; previous total
  ends-per-time           ;; how many conversations made this time period - number ended
  active-conversations    ;; total number of conversations currently active
  friend-total            ;; keep track of conversations - strangers, acquaintences, buddies

  ;External influence counters and statistics
  externals               ;; total number of external mass media contacts

  ;Color
  tech0-color
  tech1-color
  tech2-color

  ;time
  time-units
]

;Attributes for patches (other than Netlogo-defined attributes)
patches-own [
 intensity               ;; used to create degrees of influence (rather than a static background)
 original-color          ;; used in conjunction with external influence
]

;People have attributes
people-own [
  status                 ;; 0 for a potential, 1 for type 1 innovation (adoption), 2 for type 2 innovation (disruption)
  kind                   ;; 1 - 5 are "innovator","early-tech1","early-majority","late-majority","laggard" (using Rogers' terms).
  acceptance             ;; general acceptance level, where "acceptance" gives probability of someone accepting technology 1 or 2
  initiator?             ;; keep track of who initiates the conversation
  partner                ;; The person that is our current partner in a conversation
  media?                 ;; Keep track of whether individual is listening to mass media presentation, such as billboard or magazine ad
  start-time             ;; when current conversation starts
end -time               ;; when current conversation will end
  num-conversations      ;; cumulative number of conversations
  total-interact-time    ;; cumulative time spent in conversation
  num-externals          ;; cumulative number of interactions with external media
  total-external-time    ;; cumulative time spent with external media
  memory                 ;; list of partners that can be used for altering rules of interaction in a future model
]

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;;; SETUP
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to setup
  ;; (for this model to work with NetLogo's new plotting features,
  ;; __clear-all-and-reset-ticks should be replaced with clear-all at
  ;; the beginning of your setup procedure and reset-ticks at the end
  ;; of the procedure.)
  clear-all

  ;;Check inputs
  let total-prob prob-innovator + prob-early-adopter + prob-early-majority + prob-late-majority + prob-laggard
  if (total-prob != 100 )
  [
      print (word "Adoption types must sum to 100, but instead sum to " total-prob)
      stop
  ]

  setup-globals       ;initialize to 0
  setup-env           ;patches
  setup-people        ;individuals
  setup-histo1        ;initialize graph needed at time 0
  setup-histo2        ;initialize graph needed at time 0

  reset-ticks
  set time-units 0
end 

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to setup-globals

  ;set random seed to user number unless 0 chosen
  let my-seed select-seed           ;set once at beginning of model
  if random-seed-switch? [ set my-seed new-seed ]
  random-seed my-seed
  output-print my-seed

  ;internal influence globals
  set contacts 0
  set old-contacts 0
  set contacts-per-time 0.0
  set conversation-starts 0
  set old-conversation-starts 0
  set starts-per-time 0
  set conversation-ends 0
  set old-conversation-ends 0
  set ends-per-time 0
  set active-conversations 0
  set friend-total 0

  ;external influence globals
  set externals 0

  ;color
  set tech0-color black
  set tech1-color magenta
  set tech2-color violet
end 

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to setup-env
  ;all patches set to default initially - intensity not used on black patches in current version of model
  ask patches [
    set pcolor tech0-color
    set intensity (random 100)
    set original-color tech0-color
  ]

  ;Mass media center for first new technology if turned on by switch - Set up as a square of color violet
  if External-Tech1? [
    let x int(x-adopt / 100 * max-pxcor)
    let y int(y-adopt / 100 * max-pycor)
    let s int(s-adopt / 100 * (max-pxcor + 1))
    ask patches [
      if (pxcor > x - s) and (pxcor < x + s)
         and (pycor > y - s) and (pycor < y + s) [
         set pcolor tech1-color
         set original-color tech1-color
      ]
    ]
  ]

  ;Mass media center for second new technology (if switch turned on) to challenge first technological innovation - magenta square
  if External-Tech2? [
    let x int(x-disrupt / 100 * max-pxcor)
    let y int(y-disrupt / 100 * max-pycor)
    let s int(s-disrupt / 100 * (max-pxcor + 1))
    ask patches [
      if (pxcor > x - s) and (pxcor < x + s)
         and (pycor > y - s) and (pycor < y + s) [
         set pcolor tech2-color
         set original-color tech2-color
      ]
    ]
  ]

  ; Patch intensity is randomly assigned to each patch.  To make more realistic,
  ; use the diffuse function to spread the value of each intensity to its nearest
  ; neighbors; the value 1 is the max. diffusion coefficient.  Repeat this
  ; diffusion step "Smoothness" times (set by user) to create a smooth topology.
  ; This applies to all patches.
  ;
  ; Rescale is like converting between degrees Centigrade and Fahrenheit - scale
  ; range from min to max => 0 to 100.  Then recolor the patches.  Only do this for
  ; non-black patches.  Thus, the intensity topology exists over the entire grid
  ; but it is only observed and used in the external patch areas.
  if Smoothness > 0 [
    repeat Smoothness [ diffuse intensity 1 ] ;smoothness function
    rescale
    recolor
  ]
end 

to rescale ;adapted from fitness model in Netlogo Community Models
   let highest max [ intensity ] of patches
   let lowest min [ intensity ] of patches
   ask patches [
     set intensity (((intensity - lowest) * 100) / (highest - lowest))
   ]
   let nhighest max [ intensity ] of patches
   let nlowest min [ intensity ] of patches
   print (word "intensity range from " lowest " to " highest " shifted to " nlowest " to " nhighest)
end 

to recolor
   ask patches [
       ifelse original-color = tech1-color
          [ set pcolor scale-color tech1-color intensity 0 100 ]
          [ ifelse original-color = tech2-color
               [ set pcolor scale-color tech2-color intensity 0 100 ]
               [ set pcolor tech0-color ] ;ignore for black patches
          ]
   ]
end 

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to setup-people

  create-people total-population [
    setxy random-pxcor random-pycor ; centers on patch
    set end-time 0
    set total-interact-time 0
    set num-conversations 0
    set total-external-time 0
    set num-externals 0
    set partner nobody
    set shape "person"
    set status 0 ;default is potential
    set initiator? FALSE
    set media? FALSE
    set memory []

    ;determine kind of individual - from innovator to laggard.
    let kind-prob (random 100)
    let cumulative-prob prob-innovator
    ifelse (kind-prob < cumulative-prob)
    [
            set-innovator
    ]
    [
            set cumulative-prob cumulative-prob + prob-early-adopter
            ifelse (kind-prob < cumulative-prob)
            [
                   set-early-adopter
            ]
            [
                   set cumulative-prob cumulative-prob + prob-early-majority
                   ifelse (kind-prob < cumulative-prob)
                   [
                          set-early-majority
                   ]
                   [
                          set cumulative-prob cumulative-prob + prob-late-majority
                          ifelse (kind-prob < cumulative-prob)
                          [
                                  set-late-majority
                          ]
                          [
                                  set cumulative-prob cumulative-prob + prob-laggard
                                  ifelse (kind-prob < cumulative-prob)
                                  [
                                      set-laggard
                                  ]
                                  [
                                      print (word "Adoption Group Error: Cumulative probability of " cumulative-prob " is less than 100%")
                                  ]
                          ]
                 ]
           ]
     ]
  ]
end 

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;These are the kinds of people in a population.   Each has a factor by which the acceptance rate (overall) is divided
;in order to determine how quickly the technology or idea is accepted. The innovators will have already adopted the
;technology - either all tech1 or all tech2 or divided between them at the start of the simulation

to set-innovator
   set-change-agent
   set kind 1
   set acceptance innovator
   set color red
end 

;To load some members of the population with the new technology.

to set-change-agent
   ifelse (Internal-Tech1?)
   [
      ifelse (Internal-Tech2?)
      [
         ifelse (random 100 < change-agent)
         [
            set-tech1
         ]
         [
            set-tech2
         ]
      ]
      [
         set-tech1
      ]
   ]
   [
      if (Internal-Tech2?)
      [
         set-tech2
      ]
   ]
end 

;These are the two technologies or ideas introduced into the population.
;Tech-1 is the adoption - i.e., the first new technology.  Tech-2 is a disruptive technology, something that
;comes in at a later time, but while Tech-1 is still fresh in people's minds.

to set-tech1
   set status 1
   set size 2
   ;set shape "triangle"
end 

to set-tech2
   set status 2
   set size 2
   ;set shape "dot"
end 

to set-early-adopter
   set kind 2
   set acceptance earlyadopter
   set color green
end 

to set-early-majority
   set kind 3
   set acceptance earlymajority
   set color cyan
end 

to set-late-majority
   set kind 4
   set acceptance latemajority
   set color blue
end 

to set-laggard
   set kind 5
   set acceptance laggard
   set color magenta
end 

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;;; OUTPUT PROCEDURES
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;;;
;;; PLOTTING PROCEDURES
;;;

to setup-histo1
  ;Initial Histogram - don't set limits - let model autoset
  set-current-plot "Initial Adoption Type"
  set-histogram-num-bars 5
  update-plot-type
end 

to setup-histo2
  ;Variable Histogram
  set-current-plot "Category of Adopters"
  set-histogram-num-bars 5
  update-plot-type-current
end 

to setup-histomem
  ;Memory of individuals
  set-current-plot "Memory"
  set-histogram-num-bars 100
  update-plot-mem
end 

to update-plot-pop
  ;update time series
  let total count people
  let t2 count people with [status = 2]
  let t1 count people with [status = 1]
  let potentials ( total - t2 - t1 )

  set-current-plot "Populations"
  set-current-plot-pen "Total"
  plot total
  set-current-plot-pen "Potentials"
  plot potentials
  set-current-plot-pen "Adopters"
  plot t1
  set-current-plot-pen "Disruptors"
  plot t2

  set-current-plot "Groups"
  set-current-plot-pen "Innovators"
  plot count people with [ kind = 1 and status > 0 ]
  set-current-plot-pen "EarlyAdopter"
  plot count people with [ kind = 2 and status > 0 ]
  set-current-plot-pen "EarlyMajority"
  plot count people with [ kind = 3 and status > 0 ]
  set-current-plot-pen "LateMajority"
  plot count people with [ kind = 4 and status > 0 ]
  set-current-plot-pen "Laggard"
  plot count people with [ kind = 5 and status > 0 ]
end 

to update-plot-type
  ;update type histogram -  potentials and adopters
  set-current-plot "Initial Adoption Type"
  set-current-plot-pen "kind"
  histogram [kind] of people
end 

to update-plot-type-current
  ;update type histogram - indicates adopters
  set-current-plot "Category of Adopters"
  set-current-plot-pen "adopted"
  histogram [kind] of people with [status > 0]
end 

to update-plot-mem
  ;update memory histogram - indicates connectivity
  set-current-plot "Memory"
  set-current-plot-pen "mem"
  histogram [length memory] of people
end 

;;;
;;; MONITOR PROCEDURES
;;;

to update-monitors
  ;reset counters for each year
  set contacts-per-time (contacts - old-contacts)
  set starts-per-time (conversation-starts - old-conversation-starts)
  set ends-per-time (conversation-ends - old-conversation-ends)
  set active-conversations (conversation-starts - conversation-ends)
  set old-contacts contacts
  set old-conversation-starts conversation-starts
  set old-conversation-ends conversation-ends
end 

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;;; RULES OF INTERACTION
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; External influence rules are described here - adoption of type-1 and of type-2

to check-external-adoption
  ;adoption check (Tech1)
    ifelse ( media? = FALSE ) [
      ;Keep track of total number of externals made
      set externals (externals + 1)
      set media? TRUE
      set partner self
      set start-time ticks
      set end-time round( random-exponential listening-time ) + ticks
      print (word ticks ": external influenced adoption initiated for " who " to last until " end-time)
    ][
      ;adoption probability based on intensity of patch with white as highest, black as lowest, and color in
      ;between.  Then divide this value by the acceptance value for that person type
      ifelse ticks >= end-time [
        set media? FALSE
        set partner nobody
        let prob-to-adopt (([intensity] of patch-here / 100) * prob-to-adopt-tech1-external)
        if random-float 100 < (1.0 / acceptance) * prob-to-adopt [
          set-tech1
        ]
        ;Once done with mass media, move out of the zone
        move-away
        set num-externals (num-externals + 1)
        set total-external-time (end-time - start-time + total-external-time)
        print (word ticks ": " who " of type " kind " has finished adoption mass media session with probability of adopting " prob-to-adopt )
      ][
        print (word ticks ": " who " is listening to mass media presentation for tech1-type innovation")
      ]
    ]
end 

to check-external-disruption
  ;disruption check (Tech2) - works same way as adoption external
    ifelse ( media? = FALSE ) [
      ;Keep track of total number of externals made
      set externals (externals + 1)
      set media? TRUE
      set partner self
      set start-time ticks
      set end-time round( random-exponential listening-time ) + ticks
      print (word ticks ": external influenced disruption initiated for " who " to last until " end-time)
    ][
      ifelse ticks >= end-time [
        set media? FALSE
        set partner nobody
        let prob-to-adopt (([intensity] of patch-here / 100) * prob-to-adopt-tech2-external)
        if random-float 100 < (1.0 / acceptance) * prob-to-adopt [
          set-tech2
        ]
        move-away
        set num-externals (num-externals + 1)
        set total-external-time (end-time - start-time + total-external-time)
        print (word ticks ": " who " of type " kind " has finished disruption mass media session with probability of adopting " prob-to-adopt )
      ][
        print (word ticks ": " who " is listening to mass media presentation for tech2-type disruptive innovation")
      ]
    ]
end 

to move
    rt random-float 360
    fd movement
    setxy pxcor pycor  ;centers on patch
end 

to move-away
    rt random-float 180
    jump int(s-adopt / 100 * max-pxcor) ;move away from media center
    setxy pxcor pycor ;centers on patch
end 

;conversations are set up here

to initiate
  ;partner with someone on own patch who it not already partnered
  ifelse (any? other people-here with [partner = nobody]) [

     ;Keep track of total number of contacts made
     set contacts (contacts + 1)

     ;may not actually strike up a conversation with this partner.  The contact rate is adjusted
     ;with the "movement" parameter and the "prob-conversation" parameter.  Note also that the
     ;user controls the length of each conversation which will also impacts contact rate.
     ifelse (random-float 100) < prob-conversation [
         converse
     ][
         print (word ticks ": no conversation initiated by " who)
     ]
  ][
    print (word ticks ": no possible parters for " who)
  ]
end 

to converse
       let friend 0
       let me self

       ;Choose one of the eligible people to partner with - may want to consider other partnering strategies
       ;here - such as all on one's patch for a facilitator / hub or one of patch + neighborhood.  Change agents, etc.
       set partner one-of other turtles-here with [partner = nobody]

       ;Set partner's attribute to me.
       ask partner [ set partner me ]

       ;Put in memory and partner's memory if not already there
       ifelse (member? partner memory = true)
         [ set friend friend + 1 ]
         [ set memory lput partner memory ]
       ifelse (member? self [memory] of partner = true)
         [ set friend friend + 1 ]
         [ ask partner [ set memory lput me memory ] ]

       ;This person is the initiator, automating rendering the partner to a subordinate role
       set initiator? TRUE
       ask partner [ set initiator? FALSE ]

       ;keep track of time conversation started
       set start-time ticks
       ask partner [ set start-time ticks ]

       ;set time to end conversation.  For future changes, might consider multiple person interactions
       ;with some partners leaving early and not adopting technology
       let conversation-end round((random-float conversation-length) + ticks )
       set end-time conversation-end
       ask partner [ set end-time conversation-end ]

       ;Set patch of conversation - since xcor and ycor are real numbers, patches may not exactly
       ;coincide with position of partners
       ifelse (friend = 2)
         [ ask patch-here [ set pcolor sky ]]
         [ ifelse (friend = 1)
            [ ask patch-here [ set pcolor blue ]]
            [ ask patch-here [ set pcolor pink ]]
         ]

       ;keep track of conversations started in simulation and the level of acquaintance
       set conversation-starts (conversation-starts + 1)
       set friend-total (friend-total + friend)

       print (word ticks ": conversation between ID " who " of type " kind " with memory list " memory " and ID "
             [who] of partner " of type " [kind] of partner " with memory list " [memory] of partner " at level " friend " until " end-time " at [" xcor "," ycor "]")
end 

to interact
    ifelse (ticks <= end-time) [
       ifelse (ticks > start-time) [
         print (word ticks ": ongoing conversation between " who " and " [who] of partner)
       ][
         print (word ticks ": match already established between " who " and " [who] of partner)
       ]
    ][

       ;Decide whether to adopt the new technology when the conversation comes to a close
       ifelse status = 0 [
         ifelse Internal-Tech1? and [status] of partner = 1 [
           if random-float 100 < (1.0 / acceptance) * tech1-coefficient-acceptance [
               set-tech1
               if link-switch [ create-link-with partner]
               print (word ticks ": ID " who " of type " kind " with status " status " accepted partner " [who] of partner " of type " [kind] of partner " with status " [status] of partner)
           ]
         ]
         [
               print (word ticks ": ID " who " of type " kind " with status " status " rejected partner " [who] of partner " of type " [kind] of partner " with status " [status] of partner)
         ]
         ifelse Internal-Tech2? and [status] of partner = 2 [
             if random-float 100 < (1.0 / acceptance) * tech2-coefficient-acceptance [
                set-tech2
                if link-switch [ create-link-with partner ]
               print (word ticks ": ID " who " of type " kind " with status " status " accepted partner " [who] of partner " of type " [kind] of partner " with status " [status] of partner)
             ]
         ]
         [
               print ( word ticks ": ID " who " of type " kind " with status " status " rejected partner " [who] of partner " of type " [kind] of partner " with status " [status] of partner)
         ]
       ]
       [
               print ( word ticks ": ID " who " of type " kind " with status " status " ignored partner " [who] of partner " of type " [kind] of partner " with status " [status] of partner)
       ]

       ;stat collection
       set num-conversations (num-conversations + 1)
       set total-interact-time (end-time - start-time + total-interact-time)
       ifelse initiator? [
          set conversation-ends (conversation-ends + 1)
          ask patch-here [ set pcolor  original-color ]
          print (word ticks ": initiator " who " ends conversation with " [who] of partner)
       ][
          print (word ticks ": recipient " who " ended conversation with initiator " [who] of partner)
       ]

       set partner nobody
       rt random-float 360
       jump 5 * movement

    ]
end 

to rethink-adoption
    ifelse random-float 100 < prob-tech1-to-potential [
      set-early-adopter
      print (word ticks ": " who " reneged tech1")
    ][
      if Internal-Tech2? and random-float 100 < prob-tech1-to-tech2 [
        set-tech2
        print (word ticks ": " who " changed from tech1 to tech2 innovation")
      ]
    ]
end 

to rethink-disruption
    ifelse random-float 100 < prob-tech2-to-potential [
      set-early-adopter
      print (word ticks ": " who " reneged on tech2 back to early adopter ")
    ][
      if Internal-Tech1? and random-float 100 < prob-tech2-to-tech1 [
        set-tech1
        print (word ticks ": " who " changed back from tech2 to tech1 innovation")
      ]
    ]
end 


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;;; RUNTIME
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to go

  if (simlength > 0) [
    if (ticks >= simlength) [ stop ]
  ]


  ;People who are not currently in a conversation will:
  ; (a) think about their current adoption status, possibly changing their mind about an adoption or disruption.  They may
  ;     return to a potential, whereby they are subject to the influences of internal or external factors.
  ;     If they are already a "technologist," they may adopt the disruption if they are already an tech1 or adopt
  ;     the adoption if already a tech2. Note that this latter case is based on "personal reflection" rather than
  ;     due to external or internal influences.
  ; (b) move a little
  ; (c) check to see if they are on a "media center" patch, in which case they may adopt after hearing the message
  ; (d) they check to see if someone is around to talk to about technologies
  ;If already paired, they update their type.
  ;
  ;In latest versions of Netlogo, "without interruption" directive no longer needed
  ask people
  [
        ;external influence is only for those whose kind is not the same as the media center.
        if External-Tech1? and [pcolor] of patch-here > tech1-color - 5 and [pcolor] of patch-here < tech1-color + 5 [
          check-external-adoption
        ]
        if External-Tech2? and [pcolor] of patch-here > tech2-color - 5 and [pcolor] of patch-here < tech2-color + 5 [
          check-external-disruption
        ]

        ;internal influence - if partner = self, mass media is in effect, so internal influence is ignored in
        ;areas of mass media.  May need to reconsider this assumption.
        ifelse partner = nobody [
            if kind = 1 [rethink-adoption]
            if kind = 0 [rethink-disruption]
            move
            if [pcolor] of patch-here = black [ initiate ]
        ][
            if partner != self [
              interact
            ]
        ]
   ]

  ;plots are controlled by specific routines, not by update-plots primitive (which is run by tick now)
  update-plot-pop
  update-plot-type
  update-plot-type-current
  update-plot-mem
  update-monitors

  ;clock update
  tick
  set time-units time-units + 1
end