define ['angular', 'lodash', 'underscore.string', 'resources', 'session', 'modeling', 'clinical'], (ng, _, _s) ->
  subject = ng.module(
    'qiprofile.subject',
    ['qiprofile.resources', 'qiprofile.session', 'qiprofile.modeling', 'qiprofile.clinical']
  )

  subject.factory 'Subject', [
    'Resources', 'Session', 'Modeling', 'Clinical', 'DateHelper',
    (Resources, Session, Modeling, Clinical, DateHelper) ->
      isSession = (encounter) -> encounter._cls == 'Session'
    
      isClinical = (encounter) -> not isSession(encounter)

      # Fixes the subject date properties.
      fixDates = (subject)  ->
        # Fix the birth date.
        if subject.birthDate?
          date = DateHelper.asMoment(subject.birthDate)
          # Anonymize the birth date.
          subject.birthDate = DateHelper.anonymize(date)
  
        # Fix the encounter dates.
        for enc in subject.encounters
          if enc.date?
            enc.date = DateHelper.asMoment(enc.date)

        # Fix the treatment dates.
        for trt in subject.treatments
          trt.startDate = DateHelper.asMoment(trt.startDate)
          trt.endDate = DateHelper.asMoment(trt.endDate)
          for dosage in trt.dosages
            dosage.startDate = DateHelper.asMoment(trt.startDate)

      # Makes the changes to the subject session objects
      # described in Session.extend.
      extendSessions = (subject)  ->
        # Extend each session.
        for session, i in subject.sessions
          Session.extend(session, subject, i+1)

      # Adds the clinical encounter title virtual property.
      extendClincalEncounters = (subject) ->
        for enc in subject.clinicalEncounters
          Clinical.extend(enc)

      # Makes the following changes to the given subject object:
      # * adds parent references
      # * fixes dates
      # * adds the subject modeling property
      #
      # @param subject the REST Subject object to extend
      # @return the extended Subject
      extend = (subject) ->
        # Add the virtual properties.
        Object.defineProperties subject,
          # @returns the subject display title
          title:
            get: ->
              # TODO - get the Subject display text from a config,
              #   e.g.:
              #     label = config.subject.label
              #     "#{ @collection } #{ label } #{ @number }"
              #   See also the subject.coffee title TODO.
              "#{ @collection } Patient #{ @number }"

          # Returns the /project/collection/subject path, where:
          # * *project* is the lower-case project name
          # * *collection* is the lower-case collection name
          # * *subject* is the subject number
          #
          # @returns the session path
          path:
            get: ->
              "#{ @project.toLowerCase() }/#{ @collection.toLowerCase() }/#{ @number }"

          # @returns the clinical encounters
          clinicalEncounters:
            get: ->
              (enc for enc in @encounters when isClinical(enc))
  
          # @returns the session encounters
          sessions:
            get: ->
              (enc for enc in @encounters when isSession(enc))

          # @returns the modelings array
          modelings:
            get: ->
              # Create on demand.
              if not @_modelings?
                @_modelings = Modeling.collect(this)
              @_modelings      

        # Add the isMultiSession method.
        subject.isMultiSession = -> @sessions.length > 1

        # Fix the subject dates.
        fixDates(subject)
        # Doctor the encounters.
        extendSessions(subject)
        extendClincalEncounters(subject)
    
        # Return the extended subject.
        subject
        
      # Fetches a subject REST object which matches the given search
      # condition.
      #
      # The subject object is extended as follows:
      # * anonymize the birth date by setting it to July 7
      # * add the age property
      # * convert the session and encounter dates into moments
      # * set the subject isMultiSession method
      #
      # When this function is called from a ui-route state resolve,
      # the promise is automatically resolved to the extended subject
      # REST object.
      #
      # @param condition the primary or secondary key search
      #   condition
      # @returns a promise which resolves to the extended subject
      #   REST object
      # @throws ValueError if the template does not have a searchable
      #  key, either the id or the complete secondary key
      # @throws ReferenceError if no such subject was found
      find: (condition) ->
        # Fetch the subject REST object.
        Resources.Subject.find(condition).then(extend)

      # Fetches the subject REST objects which matches the given search
      # condition. Each subject object is extended as described in
      # find_one.
      #
      # When this function is called from a ui-route state resolve,
      # the promise is automatically resolved to the extended subject
      # REST objects.
      #
      # @param condition the primary or secondary key search
      #   condition
      # @returns a promise which resolves to the (possibly empty)
      #   extended subject REST objects array
      query: (condition) ->
        # Fetch the subjects which match the criteria.
        Resources.Subject.query(condition).then (result) ->
          # Extend the result objects.
          result.map(extend)  
      
      # @param session the session object
      # @returns the href to the session detail page
      hyperlink: (subject) ->
        sbjRefUrl = "/quip/#{ subject.collection }/subject/#{ subject.number }"
        "#{ sbjRefUrl }?project=#{ subject.project }"
  ]