# frozen_string_literal: true

class LlmModel < ActiveRecord::Base
  FIRST_BOT_USER_ID = -1200
  RESERVED_VLLM_SRV_URL = "https://vllm.shadowed-by-srv.invalid"

  belongs_to :user

  validates :url, exclusion: { in: [RESERVED_VLLM_SRV_URL] }
  before_save :toggle_companion_user_before_save

  def self.enable_or_disable_srv_llm!
    srv_model = find_by(url: RESERVED_VLLM_SRV_URL)
    if SiteSetting.ai_vllm_endpoint_srv.present? && srv_model.blank?
      record =
        new(
          display_name: "vLLM SRV LLM",
          name: "mistralai/Mixtral",
          provider: "vllm",
          tokenizer: "DiscourseAi::Tokenizer::MixtralTokenizer",
          url: RESERVED_VLLM_SRV_URL,
          max_prompt_tokens: 8000,
        )

      record.save(validate: false) # Ignore reserved URL validation
    elsif srv_model.present?
      srv_model.destroy!
    end
  end

  def toggle_companion_user_before_save
    toggle_companion_user if enabled_chat_bot_changed? || new_record?
  end

  def toggle_companion_user
    return if name == "fake" && Rails.env.production?

    enable_check = SiteSetting.ai_bot_enabled && enabled_chat_bot

    if enable_check
      if !user
        next_id = DB.query_single(<<~SQL).first
          SELECT min(id) - 1 FROM users
        SQL

        new_user =
          User.new(
            id: [FIRST_BOT_USER_ID, next_id].min,
            email: "no_email_#{SecureRandom.hex}",
            name: name.titleize,
            username: UserNameSuggester.suggest(name),
            active: true,
            approved: true,
            admin: true,
            moderator: true,
            trust_level: TrustLevel[4],
          )
        new_user.save!(validate: false)
        self.update!(user: new_user)
      else
        user.active = true
        user.save!(validate: false)
      end
    elsif user
      # will include deleted
      has_posts = DB.query_single("SELECT 1 FROM posts WHERE user_id = #{user.id} LIMIT 1").present?

      if has_posts
        user.update!(active: false) if user.active
      else
        user.destroy!
        self.update!(user: nil)
      end
    end
  end

  def tokenizer_class
    tokenizer.constantize
  end
end

# == Schema Information
#
# Table name: llm_models
#
#  id                :bigint           not null, primary key
#  display_name      :string
#  name              :string           not null
#  provider          :string           not null
#  tokenizer         :string           not null
#  max_prompt_tokens :integer          not null
#  created_at        :datetime         not null
#  updated_at        :datetime         not null
#  url               :string
#  api_key           :string
#  user_id           :integer
#  enabled_chat_bot  :boolean          default(FALSE), not null
#