ytdl_hook.lua: add include script-opt of URLs to try with ytdl first

By the default mpv tries opening URLs with ffmpeg first, and users who
don't configure try_ytdl_first get a slower startup for youtube URLs, on
top of yt-dlp already being slow.

Fix this by adding a script-opt of URL pattern to try with ytdl first.
Youtube and twitch are included by default.

Compared to the alternative of trying ytdl first by default and
excluding URLs with a media extension, this only works for the sites
explicitly included in the new option's value, but doesn't have false
positives on media URLs without an extension.

DOCS/interface-changes/ytdl_hook-include.txt

@@ -0,0 +1 @@
+add `ytdl_hook-include` script-opt

DOCS/man/options.rst

@@ -919,6 +919,13 @@ Program Behavior
 
         See more lua patterns here: https://www.lua.org/manual/5.1/manual.html#5.4.1
 
+    ``include=<URL1|URL2|...``
+        A ``|``-separated list of URL patterns which mpv should try to parse with
+        youtube-dl first when ``try_ytdl_first`` is ``no``. The patterns are
+        matched in the same way as ``exclude``.
+
+        Default: ``^%w+%.youtube%.com/|^youtube%.com/|^youtu%.be/|^%w+%.twitch%.tv/|^twitch%.tv/``
+
     ``all_formats=<yes|no>``
         If 'yes' will attempt to add all formats found reported by youtube-dl
         (default: no). Each format is added as a separate track. In addition,

player/lua/ytdl_hook.lua

@@ -4,6 +4,7 @@ local options = require 'mp.options'
 
 local o = {
     exclude = "",
+    include = "^%w+%.youtube%.com/|^youtube%.com/|^youtu%.be/|^%w+%.twitch%.tv/|^twitch%.tv/",
     try_ytdl_first = false,
     use_manifests = false,
     all_formats = false,
@@ -283,6 +284,26 @@ local function extract_chapters(data, video_length)
     return ret
 end
 
+local function is_whitelisted(url)
+    url = url:match("https?://(.+)")
+
+    if url == nil then
+        return false
+    end
+
+    url = url:lower()
+
+    for match in o.include:gmatch('%|?([^|]+)') do
+        if url:find(match) then
+            msg.verbose("URL matches included substring " .. match ..
+                        ". Trying ytdl first.")
+            return true
+        end
+    end
+
+    return false
+end
+
 local function is_blacklisted(url)
     if o.exclude == "" then return false end
     if #ytdl.blacklisted == 0 then
@@ -1177,7 +1198,7 @@ end
 local function on_load_hook(load_fail)
     local url = mp.get_property("stream-open-filename", "")
     local force = url:find("^ytdl://")
-    local early = force or o.try_ytdl_first
+    local early = force or o.try_ytdl_first or is_whitelisted(url)
     if early == load_fail then
         return
     end