defmodule ConfigHelper do
  require Logger

  import Bitwise
  alias Explorer.ExchangeRates.Source
  alias Explorer.Market.History.Source.{MarketCap, Price, TVL}
  alias Indexer.Transform.Blocks

  def repos do
    base_repos = [Explorer.Repo, Explorer.Repo.Account]

    chain_type_repo =
      %{
        arbitrum: Explorer.Repo.Arbitrum,
        blackfort: Explorer.Repo.Blackfort,
        celo: Explorer.Repo.Celo,
        ethereum: Explorer.Repo.Beacon,
        filecoin: Explorer.Repo.Filecoin,
        optimism: Explorer.Repo.Optimism,
        polygon_edge: Explorer.Repo.PolygonEdge,
        polygon_zkevm: Explorer.Repo.PolygonZkevm,
        rsk: Explorer.Repo.RSK,
        scroll: Explorer.Repo.Scroll,
        shibarium: Explorer.Repo.Shibarium,
        stability: Explorer.Repo.Stability,
        suave: Explorer.Repo.Suave,
        zilliqa: Explorer.Repo.Zilliqa,
        zksync: Explorer.Repo.ZkSync
      }
      |> Map.get(chain_type())

    chain_type_repos = (chain_type_repo && [chain_type_repo]) || []

    ext_repos =
      [
        {parse_bool_env_var("BRIDGED_TOKENS_ENABLED"), Explorer.Repo.BridgedTokens},
        {parse_bool_env_var("MUD_INDEXER_ENABLED"), Explorer.Repo.Mud},
        {parse_bool_env_var("SHRINK_INTERNAL_TRANSACTIONS_ENABLED"), Explorer.Repo.ShrunkInternalTransactions}
      ]
      |> Enum.filter(&elem(&1, 0))
      |> Enum.map(&elem(&1, 1))

    base_repos ++ chain_type_repos ++ ext_repos
  end

  @spec hackney_options() :: any()
  def hackney_options() do
    basic_auth_user = System.get_env("ETHEREUM_JSONRPC_USER", "")
    basic_auth_pass = System.get_env("ETHEREUM_JSONRPC_PASSWORD", nil)

    [pool: :ethereum_jsonrpc]
    |> (&if(System.get_env("ETHEREUM_JSONRPC_HTTP_INSECURE", "") == "true", do: [:insecure] ++ &1, else: &1)).()
    |> (&if(basic_auth_user != "" && !is_nil(basic_auth_pass),
          do: [basic_auth: {basic_auth_user, basic_auth_pass}] ++ &1,
          else: &1
        )).()
  end

  @spec timeout(non_neg_integer()) :: non_neg_integer()
  def timeout(default_minutes \\ 1) do
    case Integer.parse(safe_get_env("ETHEREUM_JSONRPC_HTTP_TIMEOUT", "#{default_minutes * 60}")) do
      {seconds, ""} -> seconds
      _ -> default_minutes * 60
    end
    |> :timer.seconds()
  end

  @spec parse_integer_env_var(String.t(), integer()) :: non_neg_integer()
  def parse_integer_env_var(env_var, default_value) do
    env_var
    |> safe_get_env(to_string(default_value))
    |> Integer.parse()
    |> case do
      {integer, _} -> integer
      _ -> 0
    end
  end

  @spec parse_float_env_var(String.t(), float()) :: float()
  def parse_float_env_var(env_var, default_value) do
    env_var
    |> safe_get_env(to_string(default_value))
    |> Float.parse()
    |> case do
      {float, _} -> float
      _ -> 0
    end
  end

  @spec parse_integer_or_nil_env_var(String.t()) :: non_neg_integer() | nil
  def parse_integer_or_nil_env_var(env_var) do
    env_var
    |> System.get_env("")
    |> Integer.parse()
    |> case do
      {integer, _} -> integer
      _ -> nil
    end
  end

  @spec parse_time_env_var(String.t(), String.t() | nil) :: non_neg_integer()
  def parse_time_env_var(env_var, default_value) do
    case env_var |> safe_get_env(default_value) |> String.downcase() |> Integer.parse() do
      {milliseconds, "ms"} -> milliseconds
      {hours, "h"} -> :timer.hours(hours)
      {minutes, "m"} -> :timer.minutes(minutes)
      {seconds, s} when s in ["s", ""] -> :timer.seconds(seconds)
      _ -> 0
    end
  end

  @doc """
  Parses value of env var through catalogued values list. If a value is not in the list, nil is returned.
  Also, the application shutdown option is supported, if a value is wrong.
  """
  @spec parse_catalog_value(String.t(), List.t(), bool(), String.t() | nil) :: atom() | nil
  def parse_catalog_value(env_var, catalog, shutdown_on_wrong_value?, default_value \\ nil) do
    value = env_var |> safe_get_env(default_value)

    if value !== "" do
      if value in catalog do
        String.to_atom(value)
      else
        if shutdown_on_wrong_value? do
          Logger.error(wrong_value_error(value, env_var, catalog))
          exit(:shutdown)
        else
          Logger.warning(wrong_value_error(value, env_var, catalog))
          nil
        end
      end
    else
      nil
    end
  end

  defp wrong_value_error(value, env_var, catalog) do
    "Invalid value \"#{value}\" of #{env_var} environment variable is provided. Supported values are #{inspect(catalog)}"
  end

  def safe_get_env(env_var, default_value) do
    env_var
    |> System.get_env(default_value)
    |> case do
      "" -> default_value
      value -> value
    end
    |> to_string()
  end

  @spec parse_bool_env_var(String.t(), String.t()) :: boolean()
  def parse_bool_env_var(env_var, default_value \\ "false"),
    do: String.downcase(safe_get_env(env_var, default_value)) == "true"

  @spec cache_ttl_check_interval(boolean()) :: non_neg_integer() | false
  def cache_ttl_check_interval(disable_indexer?) do
    if(disable_indexer?, do: :timer.seconds(1), else: false)
  end

  @spec cache_global_ttl(boolean()) :: non_neg_integer()
  def cache_global_ttl(disable_indexer?) do
    if(disable_indexer?, do: :timer.seconds(5))
  end

  @spec indexer_memory_limit() :: integer()
  def indexer_memory_limit do
    "INDEXER_MEMORY_LIMIT"
    |> safe_get_env(nil)
    |> String.downcase()
    |> Integer.parse()
    |> case do
      {integer, g} when g in ["g", "gb", ""] -> integer <<< 30
      {integer, m} when m in ["m", "mb"] -> integer <<< 20
      _ -> nil
    end
  end

  @spec exchange_rates_source() :: Source.CoinGecko | Source.CoinMarketCap | Source.Mobula
  def exchange_rates_source do
    case System.get_env("EXCHANGE_RATES_SOURCE") do
      "coin_gecko" -> Source.CoinGecko
      "coin_market_cap" -> Source.CoinMarketCap
      "mobula" -> Source.Mobula
      _ -> Source.CoinGecko
    end
  end

  @spec exchange_rates_secondary_coin_source() :: Source.CoinGecko | Source.CoinMarketCap | Source.Mobula
  def exchange_rates_secondary_coin_source do
    case System.get_env("EXCHANGE_RATES_SECONDARY_COIN_SOURCE") do
      "coin_gecko" -> Source.CoinGecko
      "coin_market_cap" -> Source.CoinMarketCap
      "mobula" -> Source.Mobula
      "cryptorank" -> Source.Cryptorank
      _ -> Source.CoinGecko
    end
  end

  @spec exchange_rates_market_cap_source() :: MarketCap.CoinGecko | MarketCap.CoinMarketCap | MarketCap.Mobula
  def exchange_rates_market_cap_source do
    case System.get_env("EXCHANGE_RATES_MARKET_CAP_SOURCE") do
      "coin_gecko" -> MarketCap.CoinGecko
      "coin_market_cap" -> MarketCap.CoinMarketCap
      "mobula" -> MarketCap.Mobula
      _ -> MarketCap.CoinGecko
    end
  end

  @spec exchange_rates_tvl_source() :: TVL.DefiLlama
  def exchange_rates_tvl_source do
    case System.get_env("EXCHANGE_RATES_TVL_SOURCE") do
      "defillama" -> TVL.DefiLlama
      _ -> TVL.DefiLlama
    end
  end

  @spec exchange_rates_price_source() :: Price.CoinGecko | Price.CoinMarketCap | Price.CryptoCompare | Price.Mobula
  def exchange_rates_price_source do
    case System.get_env("EXCHANGE_RATES_PRICE_SOURCE") do
      "coin_gecko" -> Price.CoinGecko
      "coin_market_cap" -> Price.CoinMarketCap
      "crypto_compare" -> Price.CryptoCompare
      "mobula" -> Price.Mobula
      "cryptorank" -> Source.Cryptorank
      _ -> Price.CryptoCompare
    end
  end

  @spec exchange_rates_secondary_coin_price_source() ::
          Price.CoinGecko | Price.CoinMarketCap | Price.CryptoCompare | Price.Mobula
  def exchange_rates_secondary_coin_price_source do
    cmc_secondary_coin_id = System.get_env("EXCHANGE_RATES_COINMARKETCAP_SECONDARY_COIN_ID")
    cg_secondary_coin_id = System.get_env("EXCHANGE_RATES_COINGECKO_SECONDARY_COIN_ID")
    cc_secondary_coin_symbol = System.get_env("EXCHANGE_RATES_CRYPTOCOMPARE_SECONDARY_COIN_SYMBOL")
    mobula_secondary_coin_id = System.get_env("EXCHANGE_RATES_MOBULA_SECONDARY_COIN_ID")
    cryptorank_secondary_coin_id = System.get_env("EXCHANGE_RATES_CRYPTORANK_SECONDARY_COIN_ID")

    cond do
      cg_secondary_coin_id && cg_secondary_coin_id !== "" -> Price.CoinGecko
      cmc_secondary_coin_id && cmc_secondary_coin_id !== "" -> Price.CoinMarketCap
      cc_secondary_coin_symbol && cc_secondary_coin_symbol !== "" -> Price.CryptoCompare
      mobula_secondary_coin_id && mobula_secondary_coin_id !== "" -> Price.Mobula
      cryptorank_secondary_coin_id && cryptorank_secondary_coin_id !== "" -> Source.Cryptorank
      true -> Price.CryptoCompare
    end
  end

  def token_exchange_rates_source do
    case System.get_env("TOKEN_EXCHANGE_RATES_SOURCE") do
      "cryptorank" -> Source.Cryptorank
      _ -> Source.CoinGecko
    end
  end

  def block_transformer do
    block_transformers = %{
      "clique" => Blocks.Clique,
      "base" => Blocks.Base
    }

    # Compile time environment variable access requires recompilation.
    configured_transformer = safe_get_env("BLOCK_TRANSFORMER", "base")

    case Map.get(block_transformers, configured_transformer) do
      nil ->
        raise """
        No such block transformer: #{configured_transformer}.

        Valid values are:
        #{Enum.join(Map.keys(block_transformers), "\n")}

        Please update environment variable BLOCK_TRANSFORMER accordingly.
        """

      transformer ->
        transformer
    end
  end

  @spec parse_json_env_var(String.t(), String.t()) :: any()
  def parse_json_env_var(env_var, default_value \\ "{}") do
    env_var
    |> safe_get_env(default_value)
    |> Jason.decode!()
  rescue
    err -> raise "Invalid JSON in environment variable #{env_var}: #{inspect(err)}"
  end

  @spec parse_list_env_var(String.t(), String.t() | nil) :: list()
  def parse_list_env_var(env_var, default_value \\ nil) do
    addresses_var = safe_get_env(env_var, default_value)

    if addresses_var !== "" do
      addresses_list = (addresses_var && String.split(addresses_var, ",")) || []

      formatted_addresses_list =
        addresses_list
        |> Enum.map(fn addr ->
          String.downcase(addr)
        end)

      formatted_addresses_list
    else
      []
    end
  end

  @supported_chain_types [
    "default",
    "arbitrum",
    "blackfort",
    "celo",
    "ethereum",
    "filecoin",
    "optimism",
    "polygon_edge",
    "polygon_zkevm",
    "rsk",
    "scroll",
    "shibarium",
    "stability",
    "suave",
    "zetachain",
    "zilliqa",
    "zksync"
  ]

  @spec chain_type() :: atom() | nil
  def chain_type, do: parse_catalog_value("CHAIN_TYPE", @supported_chain_types, true, "default")

  @supported_modes ["all", "indexer", "api"]

  @spec mode :: atom()
  def mode, do: parse_catalog_value("APPLICATION_MODE", @supported_modes, true, "all")

  @spec eth_call_url(String.t() | nil) :: String.t() | nil
  def eth_call_url(default \\ nil) do
    System.get_env("ETHEREUM_JSONRPC_ETH_CALL_URL") || System.get_env("ETHEREUM_JSONRPC_HTTP_URL") || default
  end
end