module OWHDWallet
  class Wallet < Peatio::Wallet::Abstract
    DEFAULT_FEATURES = { skip_deposit_collection: false }.freeze
    DEFAULT_ERC20_FEE = { eth_gas_limit: 21_000, erc20_gas_limit: 90_000, gas_price: :standard }.freeze
    GAS_PRICE_THRESHOLDS = %w[standard safelow fast].freeze

    def initialize(custom_features = {})
      @features = DEFAULT_FEATURES.merge(custom_features).slice(*SUPPORTED_FEATURES)
      @settings = {}
    end

    def configure(settings = {})
      # Clean client state during configure.
      @client = nil

      @settings.merge!(settings.slice(*SUPPORTED_SETTINGS))

      @wallet = @settings.fetch(:wallet) do
        raise Peatio::Wallet::MissingSettingError, :wallet
      end.slice(:uri, :gateway_url, :address, :secret, :wallet_index)

      @currency = @settings.fetch(:currency) do
       raise Peatio::Wallet::MissingSettingError, :currency
      end.slice(:id, :base_factor, :options)
    end

    def create_address!(options = {})
      # TODO: To define coin type for btc-testnet, btc-mainnet
      response = client.rest_api(:post, '/wallet/new', {
        coin_type: coin_type
      })

      { address: response['address'], secret: response['passphrase'], details: response.except('address', 'passphrase') }
    rescue OWHDWallet::Client::Error => e
      raise Peatio::Wallet::ClientError, e
    end

    def create_transaction!(transaction, options = {})
      eth_params = coin_type == 'eth' ? eth_transaction(transaction, options) : {}

      amount = convert_to_base_unit(transaction.amount)
      response = client.rest_api(:post, '/tx/send', {
        coin_type:    coin_type,
        to:           transaction.to_address,
        amount:       amount.to_i,
        gateway_url:  wallet_gateway_url,
        wallet_index: wallet_index,
        passphrase:   wallet_secret
      }.merge(eth_params))

      transaction.hash = response['tx']
      transaction.options = response['options'] if response['options'].present?
      transaction
    rescue OWHDWallet::Client::Error => e
      raise Peatio::Wallet::ClientError, e
    end

    # Only ERC-20 transaction
    def prepare_deposit_collection!(transaction, deposit_spread, deposit_currency)
      # Don't prepare for deposit_collection in case of eth deposit.
      return [] if deposit_currency.dig(:options, :erc20_contract_address).blank?
      return [] if deposit_spread.blank?

      options = DEFAULT_ERC20_FEE.merge(deposit_currency.fetch(:options).slice(:gas_limit, :gas_price))
      gas_speed = options[:gas_price].in?(GAS_PRICE_THRESHOLDS) ? options[:gas_price] : 'standard'
      gas_limit = options[:gas_limit].present? ? options[:gas_limit].to_i : options[:erc20_gas_limit]

      response = client.rest_api(:post, '/tx/before_collect', {
        coin_type:    coin_type,
        gas_limit:    gas_limit,
        gas_speed:    gas_speed,
        spread_size:  deposit_spread.size,
        to:           transaction.to_address,
        gateway_url:  wallet_gateway_url,
        wallet_index: wallet_index,
        passphrase:   wallet_secret
      })

      transaction.currency_id = 'eth' if transaction.currency_id.blank?
      transaction.hash = response['tx']
      transaction.options = {}
      transaction.options[:gas_limit] = gas_limit
      transaction.options[:gas_price] = response['gas_price']
      [transaction]
    rescue OWHDWallet::Client::Error => e
      raise Peatio::Wallet::ClientError, e
    end

    def load_balance!
      response = client.rest_api(:post, '/wallet/balance', {
        coin_type:        coin_type,
        gateway_url:      wallet_gateway_url,
        address:          wallet_address,
        contract_address: erc20_contract_address
      }.compact).fetch('balance')

      if coin_type == 'eth'
        response = response.yield_self { |amount| convert_from_base_unit(amount) }
      end

      response.to_d
    rescue OWHDWallet::Client::Error => e
      raise Peatio::Wallet::ClientError, e
    end

    private

    def eth_transaction(transaction, options)
      currency_options = @currency.fetch(:options).slice(:gas_limit, :gas_price)
      options.merge!(currency_options, DEFAULT_ERC20_FEE)

      if transaction.options.present?
        gas_price = transaction.options[:gas_price]
      else
        gas_speed = options[:gas_price].in?(GAS_PRICE_THRESHOLDS) ? options[:gas_price] : 'standard'
      end

      params = {
        gas_price:    gas_price,
        gas_speed:    gas_speed,
        subtract_fee: options.dig(:subtract_fee).present?
      }.compact!

      if erc20_contract_address.present?
        gas_limit = options[:gas_limit].present? ? options[:gas_limit].to_i : options[:erc20_gas_limit]

        params.merge!(contract_address: erc20_contract_address, gas_limit: gas_limit)
      else
        params[:gas_limit] = options[:gas_limit].present? ? options[:gas_limit].to_i : options[:eth_gas_limit]
      end

      params
    end

    def coin_type
      if erc20_contract_address.present?
        'eth'
      else
        currency_id
      end
    end

    def convert_to_base_unit(value)
      x = value.to_d * @currency.fetch(:base_factor)
      unless (x % 1).zero?
        raise Peatio::Wallet::ClientError,
            "Failed to convert value to base (smallest) unit because it exceeds the maximum precision: " \
            "#{value.to_d} - #{x.to_d} must be equal to zero."
      end
      x.to_i
    end

    def convert_from_base_unit(value)
      value.to_d / @currency.fetch(:base_factor)
    end

    def wallet_secret
      @wallet.fetch(:secret)
    end

    def wallet_index
      @wallet.fetch(:wallet_index)
    end

    def wallet_gateway_url
      @wallet.fetch(:gateway_url)
    end

    def wallet_address
      @wallet.fetch(:address)
    end

    def currency_id
      @currency.fetch(:id)
    end

    def erc20_contract_address
      @currency.dig(:options, :erc20_contract_address)
    end

    def client
      @client ||= Client.new(@wallet.fetch(:uri), idle_timeout: 1)
    end
  end
end