class Character < ApplicationRecord
  belongs_to :user
  belongs_to :activity, optional: true
  has_many :title_awards
  has_many :titles, through: :title_awards
  belongs_to :active_title, class_name: "Title", optional: true
  has_one :hearth
  has_many :equipment
  has_many :character_items
  has_many :learned_activities
  has_many :items, through: :character_items
  has_many :character_skills
  has_many :chat_messages
  has_many :bazaar_orders
  validates :name, presence: true
  validates_length_of :name, maximum: 15, message: "can't be longer than 15 characters"
  validates_uniqueness_of :name, message: "is already being used"
  validates_format_of :name, with: /\A[a-z]+\z/i, message: "must consist of letters only"

  attribute :wounds, :integer, default: 0

  enum offensive_style: [:balanced, :precise, :brutal]
  enum defensive_style: [:centered, :elusive, :protective]

  after_create :create_skills, :set_combat_styles
  after_create { Hearth.create(character: self) }

  def beastslay_level; skill_level("beastslay"); end
  def fluxseethe_level; skill_level("fluxseethe"); end
  def havencast_level; skill_level("havencast"); end
  def hexcarve_level; skill_level("hexcarve"); end
  def magiculture_level; skill_level("magiculture"); end
  def manatrawl_level; skill_level("manatrawl"); end
  def omenbind_level; skill_level("omenbind"); end
  def otherforge_level; skill_level("otherforge"); end
  def planequarry_level; skill_level("planequarry"); end
  def spicework_level; skill_level("spicework"); end
  def synthsever_level; skill_level("synthsever"); end
  def veilreach_level; skill_level("veilreach"); end
  def wealdreap_level; skill_level("wealdreap"); end
  def wildscour_level; skill_level("wildscour"); end
  def worldcall_level; skill_level("worldcall"); end

  def vestige
    vestige = self.character_items.find_by(item: Item.find_by_gid("vestige"))
    vestige ? vestige.quantity : 0
  end

  def shift_item(item, amount)
    item = Item.find_by_gid(item) if item.is_a? String
    CharacterItem.transaction do
      ci = self.character_items.find_or_initialize_by(item: item)
      ci.increment(:quantity, amount)
      ci.save!
    end
  end

  def pay_cost_for(activity)
    CharacterItem.transaction do
      activity.whatnot[:cost]&.each do |cost|
        case cost[:type]
        when "item"
          self.shift_item(cost[:gid], -cost[:quantity])
        end
      end
    end
  end

  def has_item?(item, quantity = 1)
    item = Item.find_by_gid(item) if item.is_a? String
    ci = self.character_items.find_by(item: item)
    ci && ci.quantity >= quantity
  end

  def open_slots_for(item)
    full_slots = self.equipment.map { |e| e.slot }
    item.equip_slots.reject { |slot| full_slots.include?(slot) }
  end

  def equip(item)
    Character.transaction do
      open_slots = self.open_slots_for(item)
      raise EquipmentError unless open_slots.any?
      self.shift_item(item, -1)
      self.equipment.create!(item: item, slot: open_slots.first)
    end
  end

  def unequip(slot)
    Character.transaction do
      equipment = self.equipment.find_by(slot: slot)
      raise EquipmentError unless equipment
      item = equipment.item
      equipment.destroy!
      self.shift_item(item, 1)
    end
  end

  def add_skill_xp(skill, amount)
    skill = Skill.find_by_gid(skill) if skill.is_a? String
    Character.transaction do
      cs = self.character_skills.find_by(skill: skill)
      cs.xp += amount
      cs.save!
    end
  end

  def skill_level(skill)
    skill = Skill.find_by_gid(skill) if skill.is_a? String
    self.character_skills.find_by(skill: skill).level
  end

  def activity_time_remaining
    return nil unless self.activity
    duration_data = self.activity.whatnot[:duration]
    duration = duration_data[:base]
    duration_data[:scaling]&.each do |scaling_entry|
      case scaling_entry[:type]
      when "skill"
        duration -= self.skill_level(scaling_entry[:gid]) * scaling_entry[:scale_value]
      when "stat"
        duration -= self.total_stat_change(scaling_entry[:gid]) * scaling_entry[:scale_value]
      else
        raise "Invalid scaling type." # TODO: Improve this
      end
    end
    duration = [duration, duration_data[:minimum] || 10].max
    duration - (Time.now - self.activity_started_at)
  end

  def can_do_activity?(activity)
    return false unless activity.innate? || self.learned_activities.exists?(activity: activity)
    activity.whatnot[:cost]&.each do |cost|
      case cost[:type]
      when "item"
        return false unless self.has_item?(cost[:gid], cost[:quantity])
      end
    end
    activity.whatnot[:requirements]&.each do |requirement|
      case requirement[:type]
      when "hearth_amenity"
        return false unless self.hearth.has_amenity?(requirement[:gid], requirement[:level])
      end
    end
    true
  end

  def start_activity(activity, queued_actions: nil)
    if self.can_do_activity?(activity)
      self.update(activity: activity, activity_started_at: Time.now, queued_actions: queued_actions)
    else
      false
    end
  end

  def stop_activity
    self.update(activity: nil, activity_started_at: nil, queued_actions: nil)
  end

  def award_title(title)
    title = Title.find_by_gid(title) if title.is_a? String
    # TODO: Simplify these lines?
    return false if self.title_awards.exists?(title: title)
    self.title_awards.create(title: title)
  end

  def equipment_stats
    stats = {}
    self.equipment.each do |eq|
      eq.item.whatnot[:equip_effects]&.each do |effect|
        if effect[:type] == "stat"
          stats[effect[:gid]] ||= 0
          stats[effect[:gid]] += effect[:modifier]
        end
      end
    end
    stats
  end

  def effects
    # TODO: Review this filter_map to see if it can be simplified
    self.hearth.built_hearth_amenities.filter_map { |a| a.effects if a.effects }.flatten
  end

  def total_stat_change(stat)
    effects.filter_map { |e| e[:modifier] if e[:type] == "stat_change" && e[:stat] == stat }.sum
  end

  def can_fight?
    self.wounds < max_wounds
  end

  def max_wounds
    1 + total_stat_change("max_wounds")
  end

  def max_hp
    9 + self.beastslay_level + (equipment_stats["max_hp"] || 0)
  end

  def speed
    self.beastslay_level + (equipment_stats["speed"] || 0)
  end

  def accuracy(with_combat_style: false)
    base = self.beastslay_level + (equipment_stats["accuracy"] || 0)
    if with_combat_style && self.precise?
      base = (base * 1.25).floor
    elsif with_combat_style && self.brutal?
      base = (base * 0.75).ceil
    end
    base
  end

  def power(with_combat_style: false)
    base = self.beastslay_level + (equipment_stats["power"] || 0)
    if with_combat_style && self.precise?
      base = (base * 0.75).ceil
    elsif with_combat_style && self.brutal?
      base = (base * 1.25).floor
    end
    base
  end

  def evasion(with_combat_style: false)
    base = self.beastslay_level + (equipment_stats["evasion"] || 0)
    if with_combat_style && self.elusive?
      base = (base * 1.25).floor
    elsif with_combat_style && self.protective?
      base = (base * 0.75).ceil
    end
    base
  end

  def block(with_combat_style: false)
    base = self.beastslay_level + (equipment_stats["block"] || 0)
    if with_combat_style && self.elusive?
      base = (base * 0.75).ceil
    elsif with_combat_style && self.protective?
      base = (base * 1.25).floor
    end
    base
  end

  def block_value
    equipment_stats["block_value"] || 0
  end

  private
    def create_skills
      Skill.all.each { |skill| self.character_skills.create(skill: skill, xp: 0) }
    end

    def set_combat_styles
      self.update(offensive_style: :balanced, defensive_style: :centered)
    end
end