prompt-mpv.lua

local function message(msg)
  print(msg)
  mp.osd_message(msg)
end

local function get_platform()
  local o = {}

  if mp.get_property_native('options/vo-mmcss-profile', o) ~= o then
    return 'windows'
  elseif mp.get_property_native('options/input-app-events', o) ~= o then
    return 'macos'
  else
    return 'linux'
  end
end

local function tmpname_windows()
  return os.getenv 'TEMP' .. os.tmpname() .. 'mpv-livetweet.vbs'
end


local function system(cmd)
  local proc = io.popen(cmd)
  local body = proc:read('*all')
  local ok = proc:close()
  return ok, body
end


local function prompt_linux(default_msg)
  return system(
    'zenity ' ..
      '--title mpv-livetweet ' ..
      '--text "Tweet body" ' ..
      '--entry ' ..
      '--entry-text "' .. default_msg .. '"'
  )
end


local function prompt_macos(default_msg)
  return system(
    [[osascript ]] ..
      [[-e 'set tweet to text returned of (]] ..
        [[display dialog "Tweet body" with title "mpv-livetweet" ]] ..
        [[buttons {"Cancel", "Tweet"} ]] ..
        [[default button "Tweet" cancel button "Cancel" ]] ..
        [[default answer "]] .. default_msg .. [["]] ..
      [[)' ]] ..
      [[-e 'do shell script "echo " & quoted form of tweet']]
  )
end


local function prompt_windows(default_msg)
  local script_file = tmpname_windows()

  local script =
    'body = InputBox("Tweet body", "mpv-livetweet", "' .. default_msg .. '")\r\n' ..
    'If IsEmpty(body) Then ' ..
      'WScript.Quit(-1) ' ..
    'Else ' ..
      'WScript.Stdout.Write(body) ' ..
    'End If'
  local f = io.open(script_file, 'w')
  f:write(script)
  f:close()

  local ok, body = system('cscript /Nologo ' .. script_file)

  os.remove(script_file)

  return ok, body
end


local function prompt(OS, default_msg)
  assert(OS)
  local ok, body

  if     OS == 'linux' then
    ok, body = prompt_linux(default_msg)
  elseif OS == 'macos' then
    ok, body = prompt_macos(default_msg)
  elseif OS == 'windows' then
    ok, body = prompt_windows(default_msg)
  end

  if ok then
    return body
  end
end




mp.add_key_binding('Alt+a', function()
  local t = prompt(get_platform(), '#tfw')
  if t then message(t) end
end)