diff options
Diffstat (limited to 'plugins/xC/last-fm.lua')
| -rw-r--r-- | plugins/xC/last-fm.lua | 178 |
1 files changed, 178 insertions, 0 deletions
diff --git a/plugins/xC/last-fm.lua b/plugins/xC/last-fm.lua new file mode 100644 index 0000000..3bdfed2 --- /dev/null +++ b/plugins/xC/last-fm.lua @@ -0,0 +1,178 @@ +-- +-- last-fm.lua: "now playing" feature using the last.fm API +-- +-- Dependencies: lua-cjson (from luarocks e.g.) +-- +-- I call this style closure-oriented programming +-- +-- Copyright (c) 2016, Přemysl Eric Janouch <p@janouch.name> +-- +-- Permission to use, copy, modify, and/or distribute this software for any +-- purpose with or without fee is hereby granted. +-- +-- THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES +-- WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF +-- MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY +-- SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES +-- WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION +-- OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN +-- CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. +-- + +local cjson = require "cjson" + +-- Setup configuration to load last.fm API credentials from +local user, api_key +xC.setup_config { + user = { + type = "string", + comment = "last.fm username", + on_change = function (v) user = v end + }, + api_key = { + type = "string", + comment = "last.fm API key", + on_change = function (v) api_key = v end + }, +} + +-- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - + +-- Generic error reporting +local report_error = function (buffer, error) + buffer:log ("last-fm error: " .. error) +end + +-- Process data return by the server and extract the now playing song +local process = function (buffer, data, action) + -- There's no reasonable Lua package to parse HTTP that I could find + local s, e, v, status, message = string.find (data, "(%S+) (%S+) .+\r\n") + if not s then return "server returned unexpected data" end + if status ~= "200" then return status .. " " .. message end + + local s, e = string.find (data, "\r\n\r\n") + if not s then return "server returned unexpected data" end + + local parser = cjson.new () + data = parser.decode (string.sub (data, e + 1)) + if not data.recenttracks or not data.recenttracks.track then + return "invalid response" end + + -- Need to make some sense of the XML automatically converted to JSON + local text_of = function (node) + if type (node) ~= "table" then return node end + return node["#text"] ~= "" and node["#text"] or nil + end + + local name, artist, album + for i, track in ipairs (data.recenttracks.track) do + if track["@attr"] and track["@attr"].nowplaying then + if track.name then name = text_of (track.name) end + if track.artist then artist = text_of (track.artist) end + if track.album then album = text_of (track.album) end + end + end + + if not name then + action (false) + else + local np = "\"" .. name .. "\"" + if artist then np = np .. " by " .. artist end + if album then np = np .. " from " .. album end + action (np) + end +end + +-- Set up the connection and make the request +local on_connected = function (buffer, c, host, action) + -- Buffer data in the connection object + c.data = "" + c.on_data = function (data) + c.data = c.data .. data + end + + -- And process it after we receive everything + c.on_eof = function () + error = process (buffer, c.data, action) + if error then report_error (buffer, error) end + c:close () + end + c.on_error = function (e) + report_error (buffer, e) + end + + -- Make the unencrypted HTTP request + local url = "/2.0/?method=user.getrecenttracks&user=" .. user .. + "&limit=1&api_key=" .. api_key .. "&format=json" + c:send ("GET " .. url .. " HTTP/1.1\r\n") + c:send ("User-agent: last-fm.lua\r\n") + c:send ("Host: " .. host .. "\r\n") + c:send ("Connection: close\r\n") + c:send ("\r\n") +end + +-- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - + +-- Avoid establishing more than one connection at a time +local running + +-- Initiate a connection to last.fm servers +async, await = xC.async, coroutine.yield +local make_request = function (buffer, action) + if not user or not api_key then + report_error (buffer, "configuration is incomplete") + return + end + + if running then running:cancel () end + running = async.go (function () + local c, host, e = await (async.dial ("ws.audioscrobbler.com", 80)) + if e then + report_error (buffer, e) + else + on_connected (buffer, c, host, action) + end + running = nil + end) +end + +-- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - + +local now_playing + +local tell_song = function (buffer) + if now_playing == nil then + buffer:log ("last-fm: I don't know what you're listening to") + elseif not now_playing then + buffer:log ("last-fm: not playing anything right now") + else + buffer:log ("last-fm: now playing: " .. now_playing) + end +end + +local send_song = function (buffer) + if not now_playing then + tell_song (buffer) + else + buffer:execute ("/me is listening to " .. now_playing) + end +end + +-- Hook input to simulate new commands +xC.hook_input (function (hook, buffer, input) + if input == "/np" then + make_request (buffer, function (np) + now_playing = np + send_song (buffer) + end) + elseif input == "/np?" then + make_request (buffer, function (np) + now_playing = np + tell_song (buffer) + end) + elseif input == "/np!" then + send_song (buffer) + else + return input + end +end) |