invidious-mod/src/invidious/trending.cr

def fetch_trending(trending_type, region, locale)
  region ||= "US"
  region = region.upcase

  plid = nil

  if trending_type == "Music"
    params = "4gINGgt5dG1hX2NoYXJ0cw%3D%3D"
  elsif trending_type == "Gaming"
    params = "4gIcGhpnYW1pbmdfY29ycHVzX21vc3RfcG9wdWxhcg%3D%3D"
  elsif trending_type == "Movies"
    params = "4gIKGgh0cmFpbGVycw%3D%3D"
  else # Default
    params = ""
  end

  client_config = YoutubeAPI::ClientConfig.new(region: region)
  initial_data = YoutubeAPI.browse("FEtrending", params: params, client_config: client_config)
  trending = extract_videos(initial_data)

  return {trending, plid}
end

def extract_plid(url)
  return url.try { |i| URI.parse(i).query }
    .try { |i| HTTP::Params.parse(i)["bp"] }
    .try { |i| URI.decode_www_form(i) }
    .try { |i| Base64.decode(i) }
    .try { |i| IO::Memory.new(i) }
    .try { |i| Protodec::Any.parse(i) }
    .try &.["44:0:embedded"]?.try &.["2:1:string"]?.try &.as_s
end