youtube_playlist.lua

--[[
 Youtube playlist importer for VLC media player 1.1 and 2.0
 Copyright 2012 Guillaume Le Maout

 Authors:  Guillaume Le Maout
 Contact: http://addons.videolan.org/messages/?action=newmessage&username=exebetche

 This program is free software; you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
 the Free Software Foundation; either version 2 of the License, or
 (at your option) any later version.

 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.

 You should have received a copy of the GNU General Public License
 along with this program; if not, write to the Free Software
 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
--]]

--[[
 MODified by Kai Gillmann, 19.01.2013, [email protected]:
 VLC HAS already a youtube importer, but not for playlists. IMO this mentioned one is
 better than this one, because it opens the video in the best possible video resolution.
 So i decided to remove all parts of the code which is not responsible for list handling.
 Now this lua script parses the list, as wanted, but for each video opened, the vlc default
 Youtube script is used, so the videos will be displayed properly.
--]]

--[[
Modified again by Conrad Pankoff <[email protected]>, 2016-04-10

Switched to the JSON interface for youtube, removing the necessity for the
weird XML parsing function. This makes the code much simpler.
--]]

-- Helper function to get a parameter's value in a URL
function get_url_param(url, name)
  local _, _, res = string.find(url, "[&?]"..name.."=([^&]*)")
  return res
end

-- Probe function.
function probe()
  if vlc.access ~= "http" and vlc.access ~= "https" then
    return false
  end

  return string.match(vlc.path, "youtube.com") and string.match(vlc.path, "list=")
end

-- Parse function.
function parse()
  if not string.match(vlc.path, "list=") then
    return
  end

  local json = require("dkjson")

  local playlistID = get_url_param(vlc.path, "list")
  local playlistURL = "http://www.youtube.com/list_ajax?action_get_list=1&style=json&list="..playlistID

  local p = {}

  local id_ref = {}
  local index = 1

  while true do
    local s = vlc.stream(playlistURL.."&index="..index)

    local line = ""
    local jsonData = ""
    while line do
      jsonData = jsonData..line
      line = s:readline()
    end

    local data, _, err = json.decode(jsonData)
    if not err == nil then
      return p
    end

    for i = 1,#data.video do
      local video = data.video[i]

      if id_ref[video.encrypted_id] == i then
        return p
      else
        id_ref[video.encrypted_id] = i
      end

      local item = {}

      if video.title then
        item.title = video.title
      end

      if video.artist then
        item.artist = video.artist
      end

      if video.thumbnail then
        item.arturl = video.thumbnail
      end

      if video.description then
        item.description = video.description
      end

      if video.encrypted_id then
        item.path = "http://www.youtube.com/watch?v="..video.encrypted_id

        table.insert (p, item)
      end
    end

    if #data.video == 100 then
      index = index + 100
    else
      return p
    end
  end
end