openwebifzap.lua -- create zap requests for openwebif remote api directly from VLC.

openwebifzap.lua

-- Put this in ~/.local/share/vlc/lua/meta/reader/ 
--
--  If you're watching an Openwebif stream, or rather, if you're watching a
--  stream in VLC over http with exactly 10 values separated by colons, this
--  translates it into an API call for openWebif that will trigger your dish mover.

-- VLC requires this for script scheduling. We want this to always run, so we
-- say that it is local, even though it is making network requests.
function descriptor()
    return { scope="local" }
end

-- Extracts the domain name in vlc.path such that it can be interpolated back
-- when we make a request to zap.
function baseHost(s)
    return string.match(s, "^http://[^/]*/")
end

-- Extracts a sRef from a URL.
function refID (s)
    return string.match(s, "=.*:.*:.*:.*:.*:.*:.*:.*:.*:.*:")
end

-- Takes in a hostname and a referenceID.
function zapURL (hostname, refid)
    return (hostname .. "api/zap?sRef" .. refid)
end

-- This is the function that VLC will call in this file when it schedules us.
function read_meta()
    -- check the URI against our patterns. If it doesn't match, we shouldn't
    -- try to make a request. If it does match both, it's a reasonable guess
    -- that it is a playlist on an openwebif box.
    local base = baseHost(vlc.item:uri())
    local zapID = refID(vlc.item:uri())
    if not (base and zapID) then
        return
    end
    -- Generate a GET at the proper URL.
    vlc.stream(zapURL(base, zapID))
    return
end