# I confess that this world model heavily borrows from INSTEAD engine. - A.Y.

require('./salet.coffee')
obj = require('./obj.coffee')
markdown = require('./markdown.coffee')

assert = (msg, assertion) -> console.assert assertion, msg

Function.prototype.fcall = Function.prototype.call
Boolean.prototype.fcall = () ->
  return this.valueOf()
String.prototype.fcall = () ->
  return this

way_to = (content, ref) ->
  return "<a href='#{ref}' class='way' id='waylink-#{ref}'>#{content}</a>"

Array::remove = (e) -> @[t..t] = [] if (t = @indexOf(e)) > -1

class SaletRoom
  constructor: (spec) ->
    @visited = 0
    @title = "Room"
    @objects = {}
    @canView = true
    @canChoose = true
    @priority = 1
    @displayOrder = 1
    @tags = []
    @choices = ""
    @optionText = "Choice"

    # room illustration image, VN-style. Can be a GIF or WEBM. Can be a function.
    @pic = false
    @dsc = false # room description
    @extendSection = false
    @distance = Infinity # distance to the destination
    @clear = true # clear the screen on entering the room?
    @entering = (system, from) =>
    ###
      I call SaletRoom.exit every time the player exits to another room.
      Unlike @after this gets called after the section is closed.
      It's a styling difference.
    ###
    @exit = (system, to) =>
      return true
    
    ###
      I call SaletRoom.enter every time the player enters this room but before the section is opened.
      Unlike @before this gets called before the current section is opened.
      It's a styling difference.

      The upstream Undum version does not allow you to redefine @enter function easily but allows custom @exit one.
      It was renamed as @entering to achieve API consistency.
    ###
    @enter = (system, from) =>
      return true

    ###
      Salet's Undum version calls Situation.entering every time a situation is entered, and
      passes it three arguments; The character object, the system object,
      and a string referencing the previous situation, or null if there is
      none (ie, for the starting situation).

      My version of `enter` splits the location description from the effects.
      Also if f == this.name (we're in the same location) the `before` and `after` callbacks are ignored.
    ###
    @entering = (system, f) =>
      if @clear and f?
        system.view.clearContent()
      else
        system.view.removeTransient()

      if f != @name and f?
        @visited++
        if system.rooms[f].exit?
          system.rooms[f].exit system, @name

      if @enter
        @enter system, f

      if not @extendSection
        classes = if @classes then ' ' + @classes.join(' ') else ''
        room = document.getElementById('current-room')
        if room?
          room.removeAttribute('id')
        system.view.append "<section id='current-room' data-room='#{@name}' class='room-#{@name}#{classes}'></section>"

      if f != @name and @before?
        system.view.write markdown(@before.fcall(this, system, f))

      system.view.write @look system, f

      if f != @name and @after?
        system.view.write markdown(@after.fcall(this, system, f))

      if @beforeChoices?
        @beforeChoices.fcall(this, system, f)

      if @choices
        system.view.writeChoices(system, system.getSituationIdChoices(@choices, @maxChoices))
      
      if @afterChoices?
        @afterChoices.fcall(this, system, f)

      if system.autosave
        system.saveGame()

    ###
      An internal function to get the room's description and the descriptions of
      every object in this room.
    ###
    @look = (system, f) =>
      system.view.updateWays(system, @ways, @name)
      retval = ""

      if @pic
        retval += '<div class="pic">'+system.view.pictureTag(@pic.fcall(this, system, f))+'</div>'

      # Print the room description
      if @dsc and @dsc != ""
        dsc = @dsc.fcall(this, system, f).toString()
        retval += markdown(dsc)

      objDescriptions = []
      for thing in @objects
        if thing.name and typeof(thing.look) == "function" and thing.level == 0 and thing.look(system, f)
          objDescriptions.push ({
            order: thing.order,
            content: thing.look(system, f)
          })

      objDescriptions.sort((a, b) ->
        return a.order - b.order
      )

      for description in objDescriptions
        retval += description.content

      return retval

    ###
      Puts an object in this room.
    ###
    @take = (thing) =>
      @objects.push(thing)

    @drop = (name) =>
      for thing in @objects
        if thing.name == name
          index = @objects.indexOf(thing)
          @objects.splice(index, 1)

    ###
      Object action. A function or a string which comes when you click on the object link.
      You could interpret this as an EXAMINE verb or USE one, it's your call.
    ###
    @act = (system, action) =>
      if (link = action.match(/^_(act|cycle)_(.+)$/)) #object action
        for thing in @objects
          if thing.name == link[2]
            if link[1] == "act"
              # If it's takeable, the player can take this object.
              # If not, we check the "act" function.
              if thing.takeable
                system.character.take(thing)
                @drop name
                system.view.clearContent()
                @entering.fcall(this, system, @name)
                return system.view.write(thing.take.fcall(thing, system).toString())
              if thing.act
                system.view.changeLevel(thing.level)
                return system.view.write(
                  system.view.wrapLevel(
                    thing.act.fcall(thing, system).toString(),
                    thing.level
                  )
                )
        # the loop is done but no return came - match not found
        console.error("Could not find #{link[2]} in current room.")

      # we're done with objects, now check the regular actions
      actionClass = action.match(/^_(\w+)_(.+)$/)
      that = this

      responses = {
        writer: (ref) ->
          content = that.writers[ref].fcall(that, system, action)
          output = markdown(content)
          system.view.write(output)
        replacer: (ref) ->
          content = that.writers[ref].fcall(that, system, action)
          system.view.replace(content, '#'+ref)
        inserter: (ref) ->
          content = that.writers[ref].fcall(that, system, action)
          output = markdown(content)
          system.view.write(output, '#'+ref)
      }

      if (actionClass)
        # Matched a special action class
        [responder, ref] = [actionClass[1], actionClass[2]]

        if(!@writers.hasOwnProperty(actionClass[2]))
          throw new Error("Tried to call undefined writer: #{action}");
        responses[responder](ref);
      else if (@actions.hasOwnProperty(action))
        @actions[action].call(this, system, action);
      else
        throw new Error("Tried to call undefined action: #{action}");

    # Marks every room in the game with distance to this room
    @destination = () =>
      @distance = 0

      candidates = [this]
      while candidates.length > 0
        current_room = candidates.shift()
        if current_room.ways
          for node in current_room.ways
            if node.distance == Infinity
              node.distance = current_room.distance + 1
              candidates.push(node)

    @register = (salet) =>
      if not @name?
        console.error("Situation has no name")
        return this
      salet.rooms[@name] = this
      return this

    @writers = {
      cyclewriter: (salet) =>
        responses = @cycle
        if typeof responses == "function"
          responses = responses()
        cycleIndex = window.localStorage.getItem("cycleIndex")
        cycleIndex ?= 0
        response = responses[cycleIndex]
        cycleIndex++
        if cycleIndex == responses.length
          cycleIndex = 0
        window.localStorage.setItem("cycleIndex", cycleIndex)
        return salet.view.cycleLink(response)
    }

    for index, value of spec
      this[index] = value
    return this
  
room = (name, salet, spec) ->
  spec ?= {}
  spec.name = name
  return new SaletRoom(spec).register(salet)

module.exports = room