--[[
Videoclip - mp4/webm clips creator for mpv.

Copyright (C) 2021 Ren Tatsumoto

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <https://www.gnu.org/licenses/>.
]]

local NAME = 'videoclip'
local mp = require('mp')
local mpopt = require('mp.options')
local utils = require('mp.utils')
local OSD = require('osd_styler')
local p = require('platform')
local h = require('helpers')

------------------------------------------------------------
-- System-dependent variables

-- Options can be changed here or in a separate config file.
-- Config path: ~/.config/mpv/script-opts/videoclip.conf
local config = {
    -- absolute paths
    -- relative paths (e.g. ~ for home dir) do NOT work.
    video_folder_path = p.default_video_folder,
    audio_folder_path = p.default_audio_folder,
    -- The range of the CRF scale is 0–51, where 0 is lossless,
    -- 23 is the default, and 51 is worst quality possible.
    -- Insane values like 9999 still work but produce the worst quality.
    video_quality = 23,
    -- Use the slowest preset that you have patience for.
    -- https://trac.ffmpeg.org/wiki/Encode/H.264
    preset = 'faster',
    video_format = 'mp4', -- mp4, vp9, vp8
    video_bitrate = '1M',
    video_width = -2,
    video_height = 480,
    video_fps = 'auto',
    audio_format = 'opus', -- aac, opus
    audio_bitrate = '32k', -- 32k, 64k, 128k, 256k. aac requires higher bitrates.
    font_size = 24,
    clean_filename = true,
    -- Whether to upload to catbox (permanent) or litterbox (temporary)
    litterbox = true,
    -- Determines expire time of files uploaded to litterbox
    litterbox_expire = '72h', -- 1h, 12h, 24h, 72h
    sub_font = 'Noto Sans CJK JP',
}

mpopt.read_options(config, NAME)
local main_menu
local pref_menu
local encoder
local Timings

local allowed_presets = {
    ultrafast = true,
    superfast = true,
    veryfast = true,
    faster = true,
    fast = true,
    medium = true,
    slow = true,
    slower = true,
    veryslow = true,
}

------------------------------------------------------------
-- Utility functions

local function remove_extension(filename)
    return filename:gsub('%.%w+$', '')
end

local function remove_text_in_brackets(str)
    return str:gsub('%b[]', '')
end

local function remove_special_characters(str)
    return str:gsub('[%-_]', ' '):gsub('[%c%p]', ''):gsub('%s+', ' ')
end

local function human_readable_time(seconds)
    if type(seconds) ~= 'number' or seconds < 0 then
        return 'empty'
    end

    local parts = {}

    parts.h = math.floor(seconds / 3600)
    parts.m = math.floor(seconds / 60) % 60
    parts.s = math.floor(seconds % 60)
    parts.ms = math.floor((seconds * 1000) % 1000)

    local ret = string.format("%02dm%02ds%03dms", parts.m, parts.s, parts.ms)

    if parts.h > 0 then
        ret = string.format('%dh%s', parts.h, ret)
    end

    return ret
end

local function construct_filename()
    local filename = mp.get_property("filename") -- filename without path

    filename = remove_extension(filename)

    if config.clean_filename then
        filename = remove_text_in_brackets(filename)
        filename = remove_special_characters(filename)
    end

    filename = string.format(
            '%s_%s-%s',
            filename,
            human_readable_time(main_menu.timings['start']),
            human_readable_time(main_menu.timings['end'])
    )

    return filename
end

local function force_resolution(width, height, clip_fn, ...)
    local cached_prefs = {
        video_width = config.video_width,
        video_height = config.video_height,
    }
    config.video_width = width
    config.video_height = height
    clip_fn(...)
    config.video_width = cached_prefs.video_width
    config.video_height = cached_prefs.video_height
end

local function set_encoding_settings()
    if config.video_format == 'mp4' then
        config.video_codec = 'libx264'
        config.video_extension = '.mp4'
    elseif config.video_format == 'vp9' then
        config.video_codec = 'libvpx-vp9'
        config.video_extension = '.webm'
    else
        config.video_codec = 'libvpx'
        config.video_extension = '.webm'
    end

    if config.audio_format == 'aac' then
        config.audio_codec = 'aac'
        config.audio_extension = '.aac'
    else
        config.audio_codec = 'libopus'
        config.audio_extension = '.opus'
    end
end

local function validate_config()
    if not config.audio_bitrate:match('^%d+[kK]$') then
        config.audio_bitrate = (tonumber(config.audio_bitrate) or 32) .. 'k'
    end

    if not config.video_bitrate:match('^%d+[kKmM]$') then
        config.video_bitrate = '1M'
    end

    if not allowed_presets[config.preset] then
        config.preset = 'faster'
    end

    set_encoding_settings()
end

local function upload_to_catbox(outfile)
    local endpoint = config.litterbox and 'https://litterbox.catbox.moe/resources/internals/api.php' or 'https://catbox.moe/user/api.php'
    h.notify("Uploading to " .. (config.litterbox and "litterbox.catbox.moe..." or "catbox.moe..."), "info", 9999)

    -- This uses cURL to send a request to the cat-/litterbox API.
    -- cURL is included on Windows 10 and up, most Linux distributions and macOS.

    local r = h.subprocess({ -- This is technically blocking, but I don't think it has any real consequences ..?
        p.curl_exe, '-s',
        '-F', 'reqtype=fileupload',
        '-F', 'time=' .. config['litterbox_expire'],
        '-F', 'fileToUpload=@"' .. outfile .. '"',
        endpoint
    })

    -- Exit codes in the range [0, 99] are returned by cURL itself.
    -- Any other exit code means the shell failed to execute cURL.
    if r.status < 0 or r.status > 99 then
        h.notify("Error: Failed to upload. Make sure cURL is installed and in your PATH.", "error", 3)
        return
    elseif r.status ~= 0 then
        h.notify("Error: Failed to upload to " .. (config.litterbox and "litterbox.catbox.moe" or "catbox.moe"), "error", 2)
        return
    end

    mp.msg.info("Catbox URL: " .. r.stdout)
    -- Copy to clipboard
    p.copy_or_open_url(r.stdout)
end

------------------------------------------------------------
-- Provides interface for creating audio/video clips

encoder = {}

function encoder.get_ext_subs_path()
    local track_list = mp.get_property_native('track-list')
    for _, track in pairs(track_list) do
        if track.type == 'sub' and track.selected == true and track.external == true then
            return track['external-filename']
        end
    end
    return nil
end

function encoder.append_embed_subs_args(args)
    local ext_subs_path = encoder.get_ext_subs_path()
    if ext_subs_path then
        table.insert(args, #args, table.concat { '--sub-files-append=', ext_subs_path, })
    end
    table.insert(args, #args, table.concat { '--sid=', ext_subs_path and 'auto' or mp.get_property("sid") })
    table.insert(args, #args, table.concat { '--sub-delay=', mp.get_property("sub-delay") })
    return args
end

encoder.mkargs_video = function(clip_filename)
    local clip_path = utils.join_path(config.video_folder_path, clip_filename .. config.video_extension)
    local args = {
        'mpv',
        mp.get_property('path'),
        '--loop-file=no',
        '--keep-open=no',
        '--no-ocopy-metadata',
        '--no-sub',
        '--audio-channels=2',
        '--oacopts-add=vbr=on',
        '--oacopts-add=application=voip',
        '--oacopts-add=compression_level=10',
        '--vf-add=format=yuv420p',
        '--sub-font-provider=auto',
        '--embeddedfonts=yes',
        table.concat { '--sub-font=', config.sub_font },
        table.concat { '--ovc=', config.video_codec },
        table.concat { '--oac=', config.audio_codec },
        table.concat { '--start=', main_menu.timings['start'] },
        table.concat { '--end=', main_menu.timings['end'] },
        table.concat { '--aid=', mp.get_property("aid") }, -- track number
        table.concat { '--mute=', mp.get_property("mute") },
        table.concat { '--volume=', mp.get_property('volume') },
        table.concat { '--ovcopts-add=b=', config.video_bitrate },
        table.concat { '--oacopts-add=b=', config.audio_bitrate },
        table.concat { '--ovcopts-add=crf=', config.video_quality },
        table.concat { '--ovcopts-add=preset=', config.preset },
        table.concat { '--vf-add=scale=', config.video_width, ':', config.video_height },
        table.concat { '--ytdl-format=', mp.get_property("ytdl-format") },
        table.concat { '-o=', clip_path }
    }

    if config.video_fps ~= 'auto' then
        table.insert(args, #args, table.concat { '--vf-add=fps=', config.video_fps })
    end

    if mp.get_property_bool("sub-visibility") == true then
        args = encoder.append_embed_subs_args(args)
    end

    return args
end

encoder.mkargs_audio = function(clip_filename)
    local clip_path = utils.join_path(config.audio_folder_path, clip_filename .. config.audio_extension)
    return {
        'mpv',
        mp.get_property('path'),
        '--loop-file=no',
        '--keep-open=no',
        '--no-ocopy-metadata',
        '--no-sub',
        '--audio-channels=2',
        '--video=no',
        '--oacopts-add=vbr=on',
        '--oacopts-add=application=voip',
        '--oacopts-add=compression_level=10',
        table.concat { '--oac=', config.audio_codec },
        table.concat { '--start=', main_menu.timings['start'] },
        table.concat { '--end=', main_menu.timings['end'] },
        table.concat { '--volume=', mp.get_property('volume') },
        table.concat { '--aid=', mp.get_property("aid") }, -- track number
        table.concat { '--oacopts-add=b=', config.audio_bitrate },
        table.concat { '--ytdl-format=', mp.get_property("ytdl-format") },
        table.concat { '-o=', clip_path }
    }
end

encoder.create_clip = function(clip_type, on_complete)
    main_menu:close();
    if clip_type == nil then
        return
    end

    if not main_menu.timings:validate() then
        h.notify("Wrong timings. Aborting.", "warn", 2)
        return
    end

    local clip_filename = construct_filename()
    h.notify("Please wait...", "info", 9999)

    local args
    local location

    if clip_type == 'video' then
        args = encoder.mkargs_video(clip_filename)
        location = config.video_folder_path
    else
        args = encoder.mkargs_audio(clip_filename)
        location = config.audio_folder_path
    end

    local process_result = function(_, ret, _)
        if ret.status ~= 0 or string.match(ret.stdout, "could not open") then
            h.notify(string.format("Error: couldn't create the clip.\nDoes %s exist?", location), "error", 5)
        else
            h.notify(string.format("Clip saved to %s.", location), "info", 2)
            if on_complete then
                on_complete(utils.join_path(config.video_folder_path, clip_filename .. config.video_extension))
            end
        end
    end

    h.subprocess_async(args, process_result)
    main_menu.timings:reset()
end

------------------------------------------------------------
-- Menu interface

local Menu = {}
Menu.__index = Menu

function Menu:new(parent)
    local o = {
        parent = parent,
        overlay = parent and parent.overlay or mp.create_osd_overlay('ass-events'),
        keybindings = { },
    }
    return setmetatable(o, self)
end

function Menu:overlay_draw(text)
    self.overlay.data = text
    self.overlay:update()
end

function Menu:open()
    if self.parent then
        self.parent:close()
    end
    for _, val in pairs(self.keybindings) do
        mp.add_forced_key_binding(val.key, val.key, val.fn)
    end
    self:update()
end

function Menu:close()
    for _, val in pairs(self.keybindings) do
        mp.remove_key_binding(val.key)
    end
    if self.parent then
        self.parent:open()
    else
        self.overlay:remove()
    end
end

function Menu:update()
    local osd = OSD:new():size(config.font_size):align(4)
    osd:append('Dummy menu.'):newline()
    self:overlay_draw(osd:get_text())
end

------------------------------------------------------------
-- Main menu

main_menu = Menu:new()

main_menu.keybindings = {
    { key = 's', fn = function() main_menu:set_time('start') end },
    { key = 'e', fn = function() main_menu:set_time('end') end },
    { key = 'S', fn = function() main_menu:set_time_sub('start') end },
    { key = 'E', fn = function() main_menu:set_time_sub('end') end },
    { key = 'r', fn = function() main_menu:reset_timings() end },
    { key = 'c', fn = function() encoder.create_clip('video') end },
    { key = 'C', fn = function() force_resolution(1920, -2, encoder.create_clip, 'video') end },
    { key = 'a', fn = function() encoder.create_clip('audio') end },
    { key = 'x', fn = function() main_menu:create_clip_and_upload_to_catbox() end },
    { key = 'X', fn = function() force_resolution(1920, -2, main_menu.create_clip_and_upload_to_catbox) end },
    { key = 'p', fn = function() pref_menu:open() end },
    { key = 'o', fn = function() p.open('https://streamable.com/') end },
    { key = 'ESC', fn = function() main_menu:close() end },
}

function main_menu:set_time(property)
    self.timings[property] = math.max(0, mp.get_property_number('time-pos'))
    self:update()
end

function main_menu:set_time_sub(property)
    local sub_delay = mp.get_property_native("sub-delay")
    local time_pos = mp.get_property_number(string.format("sub-%s", property))

    if time_pos == nil then
        h.notify("Warning: No subtitles visible.", "warn", 2)
        return
    end

    self.timings[property] = math.max(0, time_pos + sub_delay)
    self:update()
end

function main_menu:reset_timings()
    self.timings = Timings:new()
    self:update()
end

main_menu.open = function()
    main_menu.timings = main_menu.timings or Timings:new()
    Menu.open(main_menu)
end

function main_menu:update()
    local osd = OSD:new():size(config.font_size):align(4)
    osd:submenu('Clip creator'):newline()
    osd:tab():item('Start time: '):append(human_readable_time(self.timings['start'])):newline()
    osd:tab():item('End time: '):append(human_readable_time(self.timings['end'])):newline()
    osd:submenu('Timings '):italics('(+shift use sub timings)'):newline()
    osd:tab():item('s: '):append('Set start'):newline()
    osd:tab():item('e: '):append('Set end'):newline()
    osd:tab():item('r: '):append('Reset'):newline()
    osd:submenu('Create clip '):italics('(+shift to force fullHD preset)'):newline()
    osd:tab():item('c: '):append('video clip'):newline()
    osd:tab():item('a: '):append('audio clip'):newline()
    osd:tab():item('x: '):append('video clip to ' .. (config.litterbox and 'litterbox.catbox.moe (' .. config.litterbox_expire .. ')' or 'catbox.moe')):newline()
    osd:submenu('Options '):newline()
    osd:tab():item('p: '):append('Open preferences'):newline()
    osd:tab():item('o: '):append('Open streamable.com'):newline()
    osd:tab():item('ESC: '):append('Close'):newline()

    self:overlay_draw(osd:get_text())
end

function main_menu:create_clip_and_upload_to_catbox()
    encoder.create_clip('video', upload_to_catbox)
end

------------------------------------------------------------
-- Preferences

pref_menu = Menu:new(main_menu)

pref_menu.keybindings = {
    { key = 'f', fn = function() pref_menu:cycle_video_formats() end },
    { key = 'a', fn = function() pref_menu:cycle_audio_formats() end },
    { key = 'm', fn = function() pref_menu:toggle_mute_audio() end },
    { key = 'r', fn = function() pref_menu:cycle_resolutions() end },
    { key = 'b', fn = function() pref_menu:cycle_audio_bitrates() end },
    { key = 'e', fn = function() pref_menu:toggle_embed_subtitles() end },
    { key = 'x', fn = function() pref_menu:toggle_catbox() end },
    { key = 'z', fn = function() pref_menu:cycle_litterbox_expiration() end },
    { key = 's', fn = function() pref_menu:save() end },
    { key = 'c', fn = function() end },
    { key = 'ESC', fn = function() pref_menu:close() end },
    { key = 'q', fn = function() pref_menu:close() end },
}

pref_menu.resolutions = {
    { w = config.video_width, h = config.video_height, },
    { w = -2, h = -2, },
    { w = -2, h = 240, },
    { w = -2, h = 360, },
    { w = -2, h = 480, },
    { w = -2, h = 720, },
    { w = -2, h = 1080, },
    { w = -2, h = 1440, },
    { w = -2, h = 2160, },
    selected = 1,
}
pref_menu.audio_bitrates = {
    config.audio_bitrate,
    '32k',
    '64k',
    '128k',
    '256k',
    '384k',
    selected = 1,
}

pref_menu.vid_formats = { 'mp4', 'vp9', 'vp8', }
pref_menu.aud_formats = { 'aac', 'opus', }
pref_menu.litterbox_expirations = { '1h', '12h', '24h', '72h', }

function pref_menu:get_selected_resolution()
    return string.format(
            '%s x %s',
            config.video_width == -2 and 'auto' or config.video_width,
            config.video_height == -2 and 'auto' or config.video_height
    )
end

function pref_menu:cycle_resolutions()
    self.resolutions.selected = self.resolutions.selected + 1 > #self.resolutions and 1 or self.resolutions.selected + 1
    local res = self.resolutions[self.resolutions.selected]
    config.video_width = res.w
    config.video_height = res.h
    self:update()
end

function pref_menu:cycle_audio_bitrates()
    self.audio_bitrates.selected = self.audio_bitrates.selected + 1 > #self.audio_bitrates and 1 or self.audio_bitrates.selected + 1
    config.audio_bitrate = self.audio_bitrates[self.audio_bitrates.selected]
    self:update()
end

function pref_menu:cycle_formats(config_type)
    local formats
    if config_type == 'video_format' then
        formats = pref_menu.vid_formats
    else
        formats = pref_menu.aud_formats
    end

    local selected = 1
    for i, format in ipairs(formats) do
        if config[config_type] == format then
            selected = i
            break
        end
    end
    config[config_type] = formats[selected + 1] or formats[1]
    set_encoding_settings()
    self:update()
end

function pref_menu:cycle_video_formats()
    pref_menu:cycle_formats('video_format')
end

function pref_menu:cycle_audio_formats()
    pref_menu:cycle_formats('audio_format')
end

function pref_menu:toggle_mute_audio()
    mp.commandv("cycle", "mute")
    self:update()
end

function pref_menu:toggle_embed_subtitles()
    mp.commandv("cycle", "sub-visibility")
    self:update()
end

function pref_menu:toggle_catbox()
    config['litterbox'] = not config['litterbox']
    self:update()
end

function pref_menu:cycle_litterbox_expiration()
    if not config['litterbox'] then
        return
    end
    local expirations = pref_menu.litterbox_expirations

    local selected = 1
    for i, expiration in ipairs(expirations) do
        if config['litterbox_expire'] == expiration then
            selected = i
            break
        end
    end
    config['litterbox_expire'] = expirations[selected + 1] or expirations[1]
    self:update()
end

function pref_menu:update()
    local osd = OSD:new():size(config.font_size):align(4)
    osd:submenu('Preferences'):newline()
    osd:tab():item('r: Video resolution: '):append(self:get_selected_resolution()):newline()
    osd:tab():item('f: Video format: '):append(config.video_format):newline()
    osd:tab():item('a: Audio format: '):append(config.audio_format):newline()
    osd:tab():item('b: Audio bitrate: '):append(config.audio_bitrate):newline()
    osd:tab():item('m: Mute audio: '):append(mp.get_property("mute")):newline()
    osd:tab():item('e: Embed subtitles: '):append(mp.get_property("sub-visibility")):newline()
    osd:submenu('Catbox'):newline()
    osd:tab():item('x: Using: '):append(config.litterbox and 'Litterbox (temporary)' or 'Catbox (permanent)'):newline()
    if config.litterbox then
        osd:tab():item('z: Litterbox expires after: '):append(config.litterbox_expire):newline()
    else
        osd:tab():color("b0b0b0"):text('x: Litterbox expires after: '):append("N/A"):newline()
    end
    osd:submenu('Save'):newline()
    osd:tab():item('s: Save preferences'):newline()
    self:overlay_draw(osd:get_text())
end

function pref_menu:save()
    local function lua_to_mpv(config_value)
        if type(config_value) == 'boolean' then
            return config_value and 'yes' or 'no'
        else
            return config_value
        end
    end
    local ignore_list = {
        video_extension = true,
        audio_extension = true,
        video_codec = true,
        audio_codec = true,
    }
    local mpv_dirpath = string.gsub(mp.get_script_directory(), "scripts/%w+", "")
    local config_filepath = utils.join_path(mpv_dirpath, string.format('script-opts/%s.conf', NAME))
    local handle = io.open(config_filepath, 'w')
    if handle ~= nil then
        handle:write(string.format("# Written by %s on %s.\n", NAME, os.date()))
        for key, value in pairs(config) do
            if ignore_list[key] == nil then
                handle:write(string.format('%s=%s\n', key, lua_to_mpv(value)))
            end
        end
        handle:close()
        h.notify("Settings saved.", "info", 2)
    else
        h.notify(string.format("Couldn't open %s.", config_filepath), "error", 4)
    end
end

------------------------------------------------------------
-- Timings class

Timings = {
    ['start'] = -1,
    ['end'] = -1,
}

function Timings:new(o)
    o = o or {}
    setmetatable(o, self)
    self.__index = self
    return o
end

function Timings:reset()
    self['start'] = -1
    self['end'] = -1
end

function Timings:validate()
    return self['start'] >= 0 and self['start'] < self['end']
end

------------------------------------------------------------
-- Finally, set an 'entry point' in mpv

validate_config()
mp.add_key_binding('c', 'videoclip-menu-open', main_menu.open)
mp.msg.warn("Press 'c' to open the videoclip menu.")