Class: FlowChat::Messenger::Middleware::ChoiceMapper

Inherits:
Object
  • Object
show all
Defined in:
lib/flow_chat/messenger/middleware/choice_mapper.rb

Overview

Maps a reply back to the choice key the flow used.

Two key spaces can be live at once. A tap sends the payload the renderer put on the button, which is the title shown on it, and a user who types what they read sends that same string - so both resolve through one map. Only when a number is genuinely on screen does a typed digit mean a position, which is the second space.

The title is the payload rather than a separately generated id because FlowChat::ChoiceTitles already guarantees the titles in a set are distinct, numbering the set when they would not be. A generated id needed its own uniqueness rule, and the one it had was lossy: it stripped punctuation, so "Yes!" produced the id "Yes", which was another choice's label exactly.

Direct Known Subclasses

Instagram::Middleware::ChoiceMapper

Constant Summary collapse

ID_KEY = 
"messenger.choice_mapping"
POSITION_KEY = 
"messenger.position_mapping"

Instance Method Summary collapse

Constructor Details

#initialize(app) ⇒ ChoiceMapper

Returns a new instance of ChoiceMapper.



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# File 'lib/flow_chat/messenger/middleware/choice_mapper.rb', line 22

def initialize(app)
  @app = app
  FlowChat.logger.debug { "#{self.class.name}: Initialized" }
end

Instance Method Details

#call(context) ⇒ Object 



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# File 'lib/flow_chat/messenger/middleware/choice_mapper.rb', line 27

def call(context)
  @context = context
  @session = context.session

  handle_choice_input if intercept?

  # The maps belong to exactly one screen: this turn's, if it had a
  # resolvable answer, or one that already fell out of use otherwise.
  # Either way nothing here is still owed to the next screen, so they
  # are cleared unconditionally rather than asked whether they still
  # look "live" - create_mappings immediately below repopulates them
  # whenever the app actually returns choices.
  #
  # An earlier version asked stale_mappings? that question after
  # handle_choice_input had already rewritten @context.input to the
  # *resolved* value, which can equal one of the map's own keys (an
  # Array choice's key is its label, and the wire value is the title
  # built from that label), so the check answered "still live"
  # about a value that was never a fresh reply. That let the maps
  # survive into a free-text screen and reinterpret a typed answer
  # there as the previous menu's choice. This was fixed once for
  # WhatsApp in Task 6 and once here in Task 13; both fixes had the
  # same shape and the same blind spot, which is why the guard is
  # gone rather than patched a third time.
  clear_mappings

  type, prompt, choices, media = @app.call(context)

  choices = create_mappings(choices) if choices.present?

  [type, prompt, choices, media]
end