-- WIPF Configuration Utilities

local bit = require"bit"

local wipf = require"wipflua"
local i18n = require"wipf/util/i18n"
local util_fs = require"wipf/util/fs"
local util_ip = require"wipf/util/ip"


local APP_GROUP_MAX = 10


local function parse_app(line)
  local path = string.gsub(line, "(\"?%s*)$", "")
  if path == "" then
    return
  end

  path = path:lower()

  local partial

  if path == "system" then
    path, partial = "System", false
  else
    partial = (path:sub(-1) == '*')
    if partial then
      path = path:sub(1, #path - 1)
    end
    path = util_fs.path_to_dospath(path)
  end

  return path, partial
end

local function parse_apps(text, blocked, apps_map, group_index)
  for line in string.gmatch(text, "%s*\"?([^\n]+)") do
    local app, partial = parse_app(line)

    if app then
      local app_3bits = apps_map[app] or 0
      local val_3bit = bit.bor(blocked and 2 or 1, partial and 4 or 0)
      local app_3bit = bit.lshift(val_3bit, group_index*3)
      apps_map[app] = bit.bor(app_3bits, app_3bit)
    end
  end
end

-- Convert app. group objects to plain table
local function app_groups_to_plain(app_groups)
  local group_bits = 0
  local groups, groups_count = {}, app_groups.n
  local apps_map = {}

  if groups_count > APP_GROUP_MAX then
    return nil, i18n.tr_fmt('err_conf_app_group_max', APP_GROUP_MAX)
  end

  for i = 1, groups_count do
    local app_group = app_groups[i]
    local group_index = i - 1

    if app_group:get_enabled() then
      local group_bit = bit.lshift(1, group_index)
      group_bits = bit.bor(group_bits, group_bit)
    end

    groups_count = groups_count + 1
    groups[groups_count] = app_group:get_name()

    parse_apps(app_group:get_block(), true, apps_map, group_index)
    parse_apps(app_group:get_allow(), false, apps_map, group_index)
  end

  -- fill "apps" array
  local apps, apps_count = {}, 0
  for app in pairs(apps_map) do
    apps_count = apps_count + 1
    apps[apps_count] = app
  end

  table.sort(apps)

  -- fill "apps_3bit" array
  local app_3bits = {}
  for i = 1, apps_count do
    local app = apps[i]
    app_3bits[i] = apps_map[app]
  end

  groups.n = groups_count
  app_3bits.n, apps.n = apps_count, apps_count

  return group_bits, groups, app_3bits, apps
end


-- Configuration objects meta-table
local conf_meta = {

  set_ip_include_all = function (self, bool)
    self.ip_include_all = bool
  end,
  get_ip_include_all = function (self)
    return self.ip_include_all
  end,

  set_ip_exclude_all = function (self, bool)
    self.ip_exclude_all = bool
  end,
  get_ip_exclude_all = function (self)
    return self.ip_exclude_all
  end,

  set_app_log_blocked = function (self, bool)
    self.app_log_blocked = bool
  end,
  get_app_log_blocked = function (self)
    return self.app_log_blocked
  end,

  set_app_block_all = function (self, bool)
    self.app_block_all = bool
  end,
  get_app_block_all = function (self)
    return self.app_block_all
  end,

  set_app_allow_all = function (self, bool)
    self.app_allow_all = bool
  end,
  get_app_allow_all = function (self)
    return self.app_allow_all
  end,

  set_ip_include = function (self, str)
    self.ip_include = str
  end,
  get_ip_include = function (self)
    return self.ip_include
  end,

  set_ip_exclude = function (self, str)
    self.ip_exclude = str
  end,
  get_ip_exclude = function (self)
    return self.ip_exclude
  end,

  add_app_group = function (self, app_group)
    local app_groups = self.app_groups
    table.insert(app_groups, app_group)
    app_groups.n = app_groups.n + 1
  end,

  remove_app_group = function (self, index)
    local app_groups = self.app_groups
    table.remove(app_groups, index)
    app_groups.n = app_groups.n - 1
  end,

  -- Write conf. object to buffer
  write = function (self, buf)

    local iprange_from_inc, iprange_to_inc =
        util_ip.ip4range_to_numbers(self.ip_include)
    if not iprange_from_inc then
      return nil, i18n.tr_fmt('err_conf_iprange_inc', iprange_to_inc)
    end

    local iprange_from_exc, iprange_to_exc =
        util_ip.ip4range_to_numbers(self.ip_exclude)
    if not iprange_from_exc then
      return nil, i18n.tr_fmt('err_conf_iprange_exc', iprange_to_exc)
    end

    local group_bits, groups, app_3bits, apps =
        app_groups_to_plain(self.app_groups)
    if not group_bits then
      return nil, groups
    end

    return true
  end,
}

conf_meta.__index = conf_meta

-- New conf. object
local function new_conf()
  return setmetatable({
    ip_include_all = false,
    ip_exclude_all = false,

    app_log_blocked = true,
    app_block_all = true,
    app_allow_all = false,

    ip_include = "",
    ip_exclude = "",

    app_groups = {n = 0}
  }, conf_meta)
end


-- Application group's meta-table
local app_group_meta = {

  set_name = function (self, str)
    self.name = str
  end,
  get_name = function (self)
    return self.name
  end,

  set_enabled = function (self, bool)
    self.enabled = bool
  end,
  get_enabled = function (self)
    return self.enabled
  end,

  set_block = function (self, str)
    self.block = str
  end,
  get_block = function (self)
    return self.block
  end,

  set_allow = function (self, str)
    self.allow = str
  end,
  get_allow = function (self)
    return self.allow
  end,
}

app_group_meta.__index = app_group_meta

-- New app. group object
local function new_app_group()
  return setmetatable({
    name = "",
    enabled = true,
    block = "",
    allow = ""
  }, app_group_meta)
end


return {
  APPGROUP_MAX	= APPGROUP_MAX,
  new_conf	= new_conf,
  new_app_group	= new_app_group,
}