---------------------
--! @brief create a faction object
factionsmod.new_faction = function(name)
    return {
        name = name,
        power = 0.,
        players = {},
        ranks = {["leader"] = {"disband", "claim", "invite", "build", "edit"},
                 ["member"] = {"build"}
                },
        leader = nil,
        default_rank = "member",
        default_leader_rank = "leader",
        land = {},

        ----------------------
        --  methods
        increase_power = function(self, power)
            self.power = self.power + power
        end,
        decrease_power = function(self, power)
            self.power = self.power - power
        end,
        add_player = function(self, player, rank)
            self.players[player] = rank or self.default_rank
            self:on_player_join(player)
        end,
        remove_player = function(self, player)
            self.players[player] = nil
            self:on_player_leave(player)
        end,
        can_claim_chunk = function(self, pos)
            --TODO: implement
        end,
        claim_chunk = function(self, pos)
            --TODO: implement
            self:on_claim_chunk(pos)
        end,
        lose_chunk = function(self, pos)
            --TODO: implement
            self:on_lose_chunks(pos)
        end,
        disband = function(self)
            --TODO: implement
            self:on_disband()
        end,
        set_leader = function(self, player)
            self.leader = player
            self.players[player] = self.default_leader_rank
            self:on_new_leader()
        end,
        has_permission = function(self, player, permission)
            local p = self.players[player]
            if not p then
                return false
            end
            return table.contains(self.groups[p], permission)
        end,

        -----------------------
        -- callbacks for events
        on_create = function(self)  --! @brief called when the faction is added to the global faction list
            --TODO: implement
        end,
        on_player_leave = function(self, player)
            --TODO: implement
        end,
        on_player_join = function(self, player)
            --TODO: implement
        end,
        on_claim_chunk = function(self, pos)
            --TODO: implement
        end,
        on_lose_chunk = function(self, pos)
            --TODO: implement
        end,
        on_disband = function(self, pos)
            --TODO: implement
        end,
        on_new_leader = function(self)
            --TODO: implement
        end,
    }
end