funkwlmpv/src/mpv_scripts/mpv_cache.lua

local utils = require 'mp.utils'
local msg = require 'mp.msg'
local options = require 'mp.options'


function sleep(n)
	os.execute("sleep " .. tonumber(n))
end


function createDir(dirname)
	os.execute("mkdir -p -m 711 " .. dirname)
end


function file_exists(name)
   local f = io.open(name, "r")
   return f ~= nil and io.close(f)
end


function get_url_host(s)
    return (s.."/"):match("://(.-)/")
end


function make_cache_track(url)
    find_uuid = "%x+-%x+-%x+-%x+-%x+"
    uuid = string.sub(url, string.find(url, find_uuid))
    host = get_url_host(url)
    cache_path_file = 'cache/' .. host .. '/' .. uuid .. ''
    if false == file_exists(cache_path_file) then
	createDir('cache/' .. host .. '/')
	msg.verbose('Caching ' .. cache_path_file .. '')
    	os.execute('curl -s --retry 3 "' .. url .. '" -o "' .. cache_path_file .. '"')
    	mp.set_property("stream-open-filename", cache_path_file)
    else
	msg.verbose('Already cached ' .. cache_path_file .. '')
	os.execute('touch ' .. cache_path_file .. '')
    	mp.set_property("stream-open-filename", cache_path_file)
    end
end


mp.add_hook("on_load", 11, function()
    msg.verbose('reusable cache hook activated')
    local url = mp.get_property("stream-open-filename", "")
    if true == (url:find("https?://") == 1) then
	 make_cache_track(url)
    end
end)