# == Schema Information
#
# Table name: channel_whatsapp
#
#  id                             :bigint           not null, primary key
#  message_templates              :jsonb
#  message_templates_last_updated :datetime
#  phone_number                   :string           not null
#  provider                       :string           default("default")
#  provider_config                :jsonb
#  provider_connection            :jsonb
#  created_at                     :datetime         not null
#  updated_at                     :datetime         not null
#  account_id                     :integer          not null
#
# Indexes
#
#  index_channel_whatsapp_on_phone_number      (phone_number) UNIQUE
#  index_channel_whatsapp_provider_connection  (provider_connection) WHERE ((provider)::text = ANY ((ARRAY['baileys'::character varying, 'zapi'::character varying])::text[])) USING gin # rubocop:disable Layout/LineLength
#

class Channel::Whatsapp < ApplicationRecord
  include Channelable
  include Reauthorizable

  self.table_name = 'channel_whatsapp'
  EDITABLE_ATTRS = [:phone_number, :provider, { provider_config: {} }].freeze

  # default at the moment is 360dialog lets change later.
  PROVIDERS = %w[default whatsapp_cloud baileys zapi].freeze
  before_validation :ensure_webhook_verify_token

  validates :provider, inclusion: { in: PROVIDERS }
  validates :phone_number, presence: true, uniqueness: true
  validate :validate_provider_config

  has_one :inbox, as: :channel, dependent: :destroy

  after_create :sync_templates
  before_destroy :teardown_webhooks

  before_destroy :disconnect_channel_provider, if: -> { provider_service.respond_to?(:disconnect_channel_provider) }

  def name
    'Whatsapp'
  end

  def provider_service
    case provider
    when 'whatsapp_cloud'
      Whatsapp::Providers::WhatsappCloudService.new(whatsapp_channel: self)
    when 'baileys'
      Whatsapp::Providers::WhatsappBaileysService.new(whatsapp_channel: self)
    when 'zapi'
      Whatsapp::Providers::WhatsappZapiService.new(whatsapp_channel: self)
    else
      Whatsapp::Providers::Whatsapp360DialogService.new(whatsapp_channel: self)
    end
  end

  def use_internal_host?
    provider == 'baileys' && ENV.fetch('BAILEYS_PROVIDER_USE_INTERNAL_HOST_URL', false)
  end

  def mark_message_templates_updated
    # rubocop:disable Rails/SkipsModelValidations
    update_column(:message_templates_last_updated, Time.zone.now)
    # rubocop:enable Rails/SkipsModelValidations
  end

  def update_provider_connection!(provider_connection)
    assign_attributes(provider_connection: provider_connection)
    # NOTE: Skip `validate_provider_config?` check
    save!(validate: false)
  end

  def provider_connection_data
    data = { connection: provider_connection['connection'] }
    if Current.account_user&.administrator?
      data[:qr_data_url] = provider_connection['qr_data_url']
      data[:error] = provider_connection['error']
    end
    data
  end

  def toggle_typing_status(typing_status, conversation:)
    return unless provider_service.respond_to?(:toggle_typing_status)

    recipient_id = conversation.contact.identifier || conversation.contact.phone_number
    last_message = conversation.messages.last
    provider_service.toggle_typing_status(typing_status, last_message: last_message, recipient_id: recipient_id)
  end

  def update_presence(status)
    return unless provider_service.respond_to?(:update_presence)

    provider_service.update_presence(status)
  end

  def read_messages(messages, conversation:)
    return unless provider_service.respond_to?(:read_messages)
    # NOTE: This is the default behavior, so `mark_as_read` being `nil` is the same as `true`.
    return if provider_config&.dig('mark_as_read') == false

    recipient_id = if provider == 'zapi'
                     conversation.contact.phone_number
                   else
                     conversation.contact.identifier || conversation.contact.phone_number
                   end

    provider_service.read_messages(messages, recipient_id: recipient_id)
  end

  def unread_conversation(conversation)
    return unless provider_service.respond_to?(:unread_message)

    # NOTE: For the Baileys provider, the last message is required even if it is an outgoing message.
    last_message = conversation.messages.last
    provider_service.unread_message(conversation.contact.phone_number, last_message) if last_message
  end

  def disconnect_channel_provider
    provider_service.disconnect_channel_provider
  rescue StandardError => e
    # NOTE: Don't prevent destruction if disconnect fails
    Rails.logger.error "Failed to disconnect channel provider: #{e.message}"
  end

  def received_messages(messages, conversation)
    return unless provider_service.respond_to?(:received_messages)

    recipient_id = conversation.contact.identifier || conversation.contact.phone_number
    provider_service.received_messages(recipient_id, messages)
  end

  def on_whatsapp(phone_number)
    return unless provider_service.respond_to?(:on_whatsapp)

    provider_service.on_whatsapp(phone_number)
  end

  delegate :setup_channel_provider, to: :provider_service
  delegate :send_message, to: :provider_service
  delegate :send_template, to: :provider_service
  delegate :sync_templates, to: :provider_service
  delegate :media_url, to: :provider_service
  delegate :api_headers, to: :provider_service

  def setup_webhooks
    perform_webhook_setup
  rescue StandardError => e
    Rails.logger.error "[WHATSAPP] Webhook setup failed: #{e.message}"
    prompt_reauthorization!
  end

  private

  def ensure_webhook_verify_token
    provider_config['webhook_verify_token'] ||= SecureRandom.hex(16) if provider.in?(%w[whatsapp_cloud baileys])
  end

  def validate_provider_config
    errors.add(:provider_config, 'Invalid Credentials') unless provider_service.validate_provider_config?
  end

  def perform_webhook_setup
    business_account_id = provider_config['business_account_id']
    api_key = provider_config['api_key']

    Whatsapp::WebhookSetupService.new(self, business_account_id, api_key).perform
  end

  def teardown_webhooks
    # NOTE: Guard against double execution during destruction due to the
    # `has_one :inbox, dependent: :destroy` relationship which will trigger this callback circularly
    return if @webhook_teardown_initiated

    @webhook_teardown_initiated = true
    Whatsapp::WebhookTeardownService.new(self).perform
  end
end