share/lua/sd/icast.lua

   1 --[[
   2  $Id$
   3
   4  Copyright © 2010 VideoLAN and AUTHORS
   5
   6  Authors: Julien 'Lta' BALLET <contact at lta dot io>
   7
   8  This program is free software; you can redistribute it and/or modify
   9  it under the terms of the GNU General Public License as published by
  10  the Free Software Foundation; either version 2 of the License, or
  11  (at your option) any later version.
  12
  13  This program is distributed in the hope that it will be useful,
  14  but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  GNU General Public License for more details.
  17
  18  You should have received a copy of the GNU General Public License
  19  along with this program; if not, write to the Free Software
  20  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  21 --]]
  22 local config = {}
  23       config["base_url"]     = "http://api.icast.io"
  24       config["api_base_url"] = config.base_url.."/1"
  25
  26 local json   = nil
  27 local roots  = nil
  28
  29 function json_init()
  30     if json ~= nil then return false end
  31
  32     vlc.msg.dbg("JSON parser lazy initialization")
  33     json = require ("dkjson")
  34
  35     -- Use vlc.stream to grab a remote json file, place it in a string,
  36     -- decode it and return the decoded data.
  37     json["parse_url"] = function(url)
  38         local stream = vlc.stream(url)
  39         local string = ""
  40         local line   = ""
  41
  42         repeat
  43             line = stream:readline()
  44             string = string..line
  45         until line ~= nil
  46
  47         --print(string)
  48         return json.decode(string)
  49     end
  50 end
  51
  52 -- VLC SD mandatory method, return the name and capabilities of this SD.
  53 function descriptor()
  54     return { title = "iCast Stream Directory", capabilities = {"search"} }
  55 end
  56
  57 -- Utility function to replace nils by an empty string, borrowed from icecast.lua
  58 function dropnil(s)
  59     if s == nil then return "" else return s end
  60 end
  61
  62 function roots_init()
  63     if roots ~= nil then return nil end
  64
  65     roots = {
  66         locals  = vlc.sd.add_node({title="Local Streams"}),
  67         cats    = vlc.sd.add_node({title="Categories"}),
  68         search  = nil
  69     }
  70 end
  71
  72 -- Add this station to the discovered service list.
  73 function station_add(node, station)
  74     if station.streams == nil or station.streams[1] == nil then
  75         return nil
  76     end
  77
  78     item = node:add_subitem({
  79         title = station.name,
  80         path  = station.streams[1]["uri"],
  81         meta  = {
  82             ["Listing Source"]  = "icast.io",
  83             ["Listing Type"]    = "radio",
  84             ["Icecast Bitrate"] = dropnil(station.streams[1].bitrate)
  85         }
  86     })
  87
  88     if station.slogan then
  89         item:set_name(station.name..": "..station.slogan)
  90     end
  91     if station.genre_list then
  92         item:set_genre(table.concat(station.genre_list, ", "))
  93     end
  94     if station.language then
  95         item:set_language(station.language)
  96     end
  97     if station.logo.medium then
  98         item:set_arturl(config.base_url..station.logo.medium)
  99     end
 100 end
 101
 102 -- Get an url to iCast's API, parse the returned stations and add them
 103 -- to the list of discovered medias.
 104 function stations_fetch(node, url)
 105     json_init()
 106     vlc.msg.info("Fetching stations from API ("..url..")")
 107
 108     local result = json.parse_url(config.api_base_url..url)
 109
 110     if result.stations == nil then
 111         return nil
 112     end
 113
 114     for _, station in ipairs(result.stations) do
 115         station_add(node, station)
 116     end
 117 end
 118
 119 -- VLC SD API - Search entry point
 120 function search(query)
 121     if roots.search then vlc.sd.remove_node(roots.search) end
 122
 123     roots.search = vlc.sd.add_node({title="Search Results"})
 124
 125     stations_fetch(roots.search, "/stations/search.json?q="..query.."*")
 126 end
 127
 128 -- VLC SD API - Main listing entry point
 129 function main()
 130     roots_init()
 131
 132     stations_fetch(roots.locals, "/stations/local.json")
 133
 134     vlc.msg.dbg("Fetching list of genre from API (/genres.json)")
 135     local result = json.parse_url(config.api_base_url.."/genres.json")
 136     for genre, sub_genres in pairs(result.genres) do
 137         local node = roots.cats:add_subnode({title=genre})
 138         for _, sub_genre in ipairs(sub_genres) do
 139             local sub_node = node:add_subnode({title=sub_genre})
 140             stations_fetch(sub_node, "/stations/genre/"..sub_genre..".json")
 141         end
 142     end
 143 end