require "http"
require "kemal"
require "db"

require "./routing"

Kemal.config.port = 9999
Kemal.config.host_binding = "0.0.0.0"
Kemal.config.shutdown_message = false

YTIMG_POOLS = {} of String => YoutubeConnectionPool

struct YoutubeConnectionPool
  property! url : URI
  property! capacity : Int32
  property! timeout : Float64
  property pool : DB::Pool(HTTP::Client)

  def initialize(url : URI, @capacity = 5, @timeout = 5.0)
    @url = url
    @pool = build_pool()
  end

  def size()
    return @pool.size
  end

  def client(&)
    conn = pool.checkout

    begin
      response = yield conn
    rescue ex
      puts "CLOSING CON: #{ex.message} + #{ex.inspect}"
      conn.close
      conn = make_client(url, force_resolve: true)

      response = yield conn
    ensure
      pool.release(conn)
    end

    response
  end

  def get_pool()
    return @pool
  end

  private def build_pool
    options = DB::Pool::Options.new(
      initial_pool_size: 0,
      max_pool_size: capacity,
      max_idle_pool_size: capacity,
      checkout_timeout: timeout
    )

    DB::Pool(HTTP::Client).new(options) do
      next make_client(url, force_resolve: true)
    end
  end
end

def make_client(url : URI, region = nil, force_resolve : Bool = false, force_youtube_headers : Bool = false, use_http_proxy : Bool = true)
  client = HTTP::Client.new(url)

  client.read_timeout = 10.seconds
  client.connect_timeout = 10.seconds

  return client
end

# Fetches a HTTP pool for the specified subdomain of ytimg.com
#
# Creates a new one when the specified pool for the subdomain does not exist
def get_ytimg_pool(subdomain)
  if pool = YTIMG_POOLS[subdomain]?
    return pool
  else
    puts "ytimg_pool: Creating a new HTTP pool for \"https://#{subdomain}.ytimg.com\""
    pool = YoutubeConnectionPool.new(URI.parse("https://#{subdomain}.ytimg.com"), capacity: ENV.fetch("POOL_SIZE", 100).to_i)
    YTIMG_POOLS[subdomain] = pool

    return pool
  end
end

Routing.register_all

{% if flag?(:release) || flag?(:production) %}
  Kemal.config.env = "production" if !ENV.has_key?("KEMAL_ENV")
{% end %}

Kemal.run