share/lua/website/quvi/util.lua

   1
   2 -- libquvi-scripts
   3 -- Copyright (C) 2010,2011,2013  Toni Gundogdu <legatvs@gmail.com>
   4 --
   5 -- This file is part of libquvi-scripts <http://quvi.sourceforge.net/>.
   6 --
   7 -- This library is free software; you can redistribute it and/or
   8 -- modify it under the terms of the GNU Lesser General Public
   9 -- License as published by the Free Software Foundation; either
  10 -- version 2.1 of the License, or (at your option) any later version.
  11 --
  12 -- This library is distributed in the hope that it will be useful,
  13 -- but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 -- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15 -- Lesser General Public License for more details.
  16 --
  17 -- You should have received a copy of the GNU Lesser General Public
  18 -- License along with this library; if not, write to the Free Software
  19 -- Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  20 -- 02110-1301  USA
  21 --
  22
  23 local M = {}
  24
  25 -- http://www.lua.org/pil/20.3.html
  26 function M.decode (s)
  27     r = {}
  28     for n,v in s:gmatch ("([^&=]+)=([^&=]+)") do
  29         n = M.unescape (n)
  30         r[n] = v
  31     end
  32     return r
  33 end
  34
  35 -- http://www.lua.org/pil/20.3.html
  36 function M.unescape (s)
  37     s = s:gsub ('+', ' ')
  38     s = s:gsub ('%%(%x%x)', function (h)
  39             return string.char (tonumber (h, 16))
  40         end)
  41     return s
  42 end
  43
  44 function M.slash_unescape (s)
  45     s = s:gsub ('\\(.)', '%1')
  46     return s
  47 end
  48
  49 function M.base64_decode(s)
  50     local itbl='ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/'
  51
  52     s = s:gsub('[^' .. itbl .. '=]', '')
  53
  54     return (s:gsub('.', function(x)
  55         local r = ''
  56
  57         if (x ~= '=') then
  58             local f = (itbl:find(x) - 1)
  59
  60             for i = 6, 1, -1 do
  61                 r = r .. (f % 2 ^ i - f % 2 ^ (i - 1) > 0 and '1' or '0')
  62             end
  63         end
  64
  65         return r;
  66     end):gsub('%d%d%d?%d?%d?%d?%d?%d?', function(x)
  67         local c = 0
  68
  69         if (#x == 8) then
  70             for i = 1, 8 do
  71                 c = c + (x:sub(i, i) == '1' and 2 ^ (8 - i) or 0)
  72             end
  73         end
  74
  75         return string.char(c)
  76     end))
  77 end
  78
  79 -- handles
  80 --  Check whether a website script can "handle" the specified URL
  81 -- Params:
  82 --  url     .. video page URL
  83 --  domains .. table of domain names
  84 --  paths   .. table of URL path patterns to match
  85 --  queries .. table of URL query patterns to match
  86 function M.handles(url, domains, paths, queries)
  87     if not url or not domains then
  88         return false
  89     end
  90     local U = require 'quvi/url'
  91     local t = U.parse(url)
  92 --    for k,v in pairs(t) do print(k,v) end
  93     local r = M.contains(t.host, domains)
  94     if r then
  95         if paths then
  96             r = M.contains(t.path, paths)
  97         end
  98         if r then
  99             if queries then
 100                 if t.query then
 101                     r = M.contains(t.query, queries)
 102                 else
 103                     r = false
 104                 end
 105             end
 106         end
 107     end
 108     return r
 109 end
 110
 111 function M.contains(s,t)
 112     if not s then return false end
 113     for k,v in pairs(t) do
 114         if s:find(v) then return true end
 115     end
 116     return false
 117 end
 118
 119 function M.ends(s,e) -- http://lua-users.org/wiki/StringRecipes
 120     return e == '' or s:sub(-#e) == e
 121 end
 122
 123 function M.is_higher_quality(a,b)
 124     if a.height > b.height then
 125         if a.width > b.width then
 126             if a['bitrate'] then -- Optional: bitrate
 127                 if a.bitrate > b.bitrate then
 128                     return true
 129                 end
 130             else
 131                 return true
 132             end
 133         end
 134     end
 135     return false
 136 end
 137
 138 function M.is_lower_quality(a,b)
 139     if a.height < b.height then
 140         if a.width < b.width then
 141             if a['bitrate'] then -- Optiona: bitrate
 142                 if a.bitrate < b.bitrate then
 143                     return true
 144                 end
 145             else
 146                 return true
 147             end
 148         end
 149     end
 150     return false
 151 end
 152
 153 function M.choose_format(self,
 154                          formats,
 155                          callback_choose_best,
 156                          callback_choose_default,
 157                          callback_to_s)
 158     local r_fmt = self.requested_format
 159
 160     if r_fmt == 'best' then
 161         return callback_choose_best(formats)
 162     end
 163
 164     for _,v in pairs(formats) do
 165         if r_fmt == callback_to_s(v) then
 166             return v
 167         end
 168     end
 169
 170     return callback_choose_default(formats)
 171 end
 172
 173 function M.to_timestamp(s) -- Based on <http://is.gd/ee9ZTD>
 174     local p = "%a+, (%d+) (%a+) (%d+) (%d+):(%d+):(%d+)"
 175
 176     local d,m,y,hh,mm,ss = s:match(p)
 177     if not d then error('no match: date') end
 178
 179     local MON = {Jan=1, Feb=2, Mar=3, Apr=4, May=5, Jun=6, Jul=7, Aug=8,
 180                  Sep=9, Oct=10, Nov=11, Dec=12}
 181
 182     local m = MON[m]
 183
 184     local offset = os.time() - os.time(os.date("!*t"))
 185
 186     return os.time({day=d,month=m,year=y,
 187                     hour=hh,min=mm,sec=ss}) + offset
 188 end
 189
 190 -- For very simple XML value extraction.
 191 function M.xml_get(d, e, is_cdata)
 192     local p = is_cdata and '.-%w+%[(.-)%].-' or '(.-)'
 193     local t = {'<',e,'>', p, '</',e,'>'}
 194     return d:match(table.concat(t))
 195               or error(table.concat({'no match: element: ',e}))
 196 end
 197
 198 -- For very simple JSON value extraction.
 199 function M.json_get(p, e, is_num)
 200   local c = is_num and '(%d+)' or '"(.-)"'
 201   local t = {'"',e,'":',c}
 202   return p:match(table.concat(t)) or ((is_num) and 0 or '')
 203 end
 204
 205 return M
 206
 207 -- vim: set ts=4 sw=4 tw=72 expandtab: