local iso639 = require("lib.iso639")
local mutil = require("mp.utils")
local opensubtitles = require("server.opensubtitles")
local util = require("lib.util")

local default_lang = "eng"

local note = function(str)
	mp.osd_message("mpvsub: " .. str)
end

local mkdir = function(path)
	local info = mutil.file_info(path)
	if info and not info.is_dir then
		os.remove(path)
	end

	return util.run({ "mkdir", "-p", path })
end

local sub_needed = function()
	local duration, isvideo, name

	name = mp.get_property_native("path")
	if
		name:find("https?://www.youtube.com/")
		or name:find("https?://youtu.be/")
	then
		return false
	end

	duration = mp.get_property("duration")
	if not duration or tonumber(duration) < 900 then
		return false
	end -- ensure duration is more than 15 minutes

	for _, v in pairs(mp.get_property_native("track-list")) do
		if v["type"] == "sub" then
			return false
		end
		if v["type"] == "video" then
			isvideo = true
		end
	end

	return isvideo
end

local getslang = function()
	local sslang = {}
	local slang = mp.get_property_native("slang")

	for i = 1, #slang do
		local lang = iso639.toset2(slang[i])
		if lang then
			table.insert(sslang, lang)
		end
	end

	if #sslang < 1 then
		slang.insert(default_lang)
	end

	return sslang
end

local sub_setup = function()
	local out, name, path, r, filesize, slangs, i

	note("fetching subtitle")

	out = mp.get_property_native("sub-file-paths")[1]
	if out then
		out = out:gsub("^~/", os.getenv("HOME") .. "/")
	else
		out = os.getenv("HOME") .. "/.local/share/mpv/subs"
		mp.set_property("sub-file-paths", out)
	end

	mkdir(out)
	path = mp.get_property_native("path")
	out = out .. "/" .. util.string_vid_path_to_name(path) .. ".srt"

	if not util.file_exists(path) then
		name = mp.get_property_native("media-title")
	end
	filesize = mp.get_property_native("file-size")

	i = 1
	slangs = getslang()
	repeat
		r = opensubtitles.search(path, out, {
			name = name,
			filesize = filesize,
			iso639_2_lang = slangs[i],
		})

		i = i + 1
	until r or i > #slangs

	if r then
		mp.commandv("rescan_external_files")
		mp.osd_message("fetched " .. slangs[i - 1] .. " subtitles")
	else
		note("failed to fetch subtitles")
	end
end

local file_listener = function()
	if sub_needed() then
		sub_setup()
	end
end

mp.register_event("file-loaded", file_listener)
mp.add_key_binding("b", "mpvsub", sub_setup)