-- stolen from https://github.com/xarvex/presentation.wez/blob/main/plugin/init.lua

local state_by_window = {}

local function deep_copy( value )
  if type( value ) ~= 'table' then return value end
  local copy = {}
  for key, item in pairs( value ) do
    copy[key] = deep_copy( item )
  end
  return copy
end

local function ensure_font_override( config, overrides )
  if not overrides.font then overrides.font = deep_copy( config.font or {} ) end
  if not overrides.font.font then overrides.font.font = {} end
  if not overrides.font.font[1] and config.font and config.font.font then
    overrides.font.font[1] = deep_copy( config.font.font[1] )
  end
  return overrides.font.font[1]
end

local function enable( win )
  local id = win:window_id()
  local config = win:effective_config()
  local overrides = win:get_config_overrides() or {}
  local font = ensure_font_override( config, overrides )

  state_by_window[id] = {
    active = true,
    font_size = config.font_size,
    font_weight = font and font.weight or nil,
  }

  if font then font.weight = 'DemiBold' end
  overrides.font_size = config.font_size * 2.0

  win:toggle_fullscreen()
  win:set_config_overrides( overrides )
end

local function disable( win )
  local id = win:window_id()
  local state = state_by_window[id]
  if not state then return end

  local config = win:effective_config()
  local overrides = win:get_config_overrides() or {}
  local font = ensure_font_override( config, overrides )

  if font then font.weight = state.font_weight end
  overrides.font_size = state.font_size

  win:toggle_fullscreen()
  win:set_config_overrides( overrides )
  state_by_window[id] = nil
end

local function toggle( win )
  local state = state_by_window[win:window_id()]
  if state and state.active then
    disable( win )
  else
    enable( win )
  end
end

return {
  toggle = toggle,
}