function bind(obj)
-- printf("turret_mgun.bind")
local ini = obj:spawn_ini()
if ini == nil or not ini:section_exist("logic") then
abort("turret '%s' must have logic", obj:name())
end
obj:bind_object(turret_binder(obj, ini))
end

class "turret_binder" (object_binder)

function turret_binder:__init(obj, ini) super(obj)
self.ini = ini
self.initialized = false
self.loaded = false
end

function turret_binder:reinit()
object_binder.reinit(self)
db.storage[self.object:id()] = {}
self.st = db.storage[self.object:id()]
self.heli = self.object:get_helicopter()
self.object:set_callback(callback.helicopter_on_hit, self.on_hit, self)
end

function turret_binder:update(delta)
object_binder.update(self, delta)
if not self.initialized and db.actor ~= nil then
xr_logic.initialize_obj(self.object, self.st, self.loaded, db.actor, modules.stype_heli)
self.initialized = true
end
if self.st.active_section ~= nil then
xr_logic.issue_event(self.object, self.st[self.st.active_scheme], "update", delta)
end
self:check_health()
end

function turret_binder:net_spawn(data)
if not object_binder.net_spawn(self, data) then
return false
end
self.se_obj = alife():object(self.object:id())
self.heli:SetfHealth(self.se_obj.health)
self.st.alive = self.se_obj.health > 0.005
db.add_turret(self.object)
return true
end

function turret_binder:net_destroy()
db.del_turret(self.object)
object_binder.net_destroy(self)
end

function turret_binder:net_save_relevant()
return true
end

function turret_binder:save(packet)
object_binder.save(self, packet)
xr_logic.save_obj(self.object, packet)
end

function turret_binder:load(packet)
object_binder.load(self, packet)
xr_logic.load_obj(self.object, packet)
end

function turret_binder:on_hit(power, impulse, hit_type, enemy_id)
dbglog("hit: power=%f impulse=%f hit_type=%d enemy_id=%d health=%f",
power, impulse, hit_type, enemy_id, self.heli:GetfHealth())
self.se_obj.health = self.heli:GetfHealth()
local enemy = level.object_by_id(enemy_id)
if enemy ~= nil and self.st.active_section ~= nil then
xr_logic.issue_event(self.object, self.st[self.st.active_scheme],
"hit_callback", self.object, power, nil, enemy, nil)
end
end

function turret_binder:check_health()
if self.st.alive and self.heli:GetfHealth() <= 0.005 then
explode_turret(self.object)
end
end

function explode_turret(turret)
local heli = turret:get_helicopter()
heli:ClearEnemy()
heli:Die()
local se_obj = alife():object(turret:id())
se_obj.health = 0
db.storage[turret:id()].alive = false
utils2.deferred_release(turret:id(), 5)
end


function is_friendly_turret(npc, turret, position)
    -- сначала выясним, турель ли это вообще.
    local k,v
    if turret == nil then
        -- ссылки на объект нет. что ж, бывает, попробуем
        -- определить по месту расположения.
        for k,v in pairs(db.turret) do
            local test_position = v:position()
            if test_position.x == position.x and
               test_position.z == position.z then
                turret = v
                break
            end
        end
        if turret == nil then
            return false
        end
    elseif (turret:section() ~= "turret_mgun") and (turret:section() ~= "turret_army") and (turret:section() ~= "turret_nato") then
        return false
    end
    local community = db.storage[turret:id()].community
    if community == nil then
        return false
    end
    if utils2.community_relation(community, npc) > -400 then
        return true
    end
    return false
end

function create_turret(turret_section_name, level_name, position, community, owner_gulag, search_dist, hunt_actor_prob, explode_dist, spawner)
local packet1 = utils2.packet_pool_get()
local packet2 = utils2.packet_pool_get()

local level_vertex_id, game_vertex_id = utils2.get_top_graph_ids(level_name)
local se_obj = alife():create(turret_section_name, position, level_vertex_id, game_vertex_id)
if se_obj == nil then
abort("can't create '%s' at (%f,%f,%f)")
end

-- лучше через table.concat()
local custom_data = "[logic]\nactive = turret\n[turret]\n"
if community ~= nil then
custom_data = custom_data.."community = "..community.."\n"
end
if owner_gulag ~= nil then
custom_data = custom_data.."owner_gulag = "..owner_gulag.."\n"
end
if hunt_actor_prob ~= nil then
custom_data = custom_data.."hunt_actor_prob = "..tostring(hunt_actor_prob).."\n"
else
custom_data = custom_data.."hunt_actor_prob = 50\n"
end
if search_dist ~= nil then
custom_data = custom_data.."search_dist = "..tostring(search_dist).."\n"
else
custom_data = custom_data.."search_dist = 90\n"
end
if explode_dist ~= nil then
custom_data = custom_data.."explode_dist = "..tostring(explode_dist).."\n"
else
custom_data = custom_data.."explode_dist = 1\n"
end
if spawner ~= nil then
custom_data = custom_data.."[spawner]\ncond = "..spawner.."\n"
end

se_obj:STATE_Write(packet1)
local dead_space = packet2:w_tell()

-- cse_alife_dynamic_object
utils2.packet_copy(packet2, packet1, 18)
packet1:r_stringZ()
packet2:w_stringZ(custom_data)
utils2.packet_copy(packet2, packet1, 8)
-- cse_visual
packet2:w_stringZ(packet1:r_stringZ())
utils2.packet_copy(packet2, packet1, 1)
-- cse_motion
packet2:w_stringZ(packet1:r_stringZ())
-- cse_ph_skeleton
packet2:w_stringZ(packet1:r_stringZ())
utils2.packet_copy(packet2, packet1, 3)
-- cse_alife_helicopter
packet2:w_stringZ("idle")
packet2:w_stringZ("$no_sound")
-- se_turret_mgun
packet2:w_float(1.0)

se_obj:STATE_Read(packet2, packet2:w_tell() - dead_space)

utils2.packet_pool_put(packet1)
utils2.packet_pool_put(packet2)
end

function create_dir_turret(turret_section_name, level_name, position, community, owner_gulag, search_dist, hunt_actor_prob, explode_dist, spawner)
local packet1 = utils2.packet_pool_get()
local packet2 = utils2.packet_pool_get()

local level_vertex_id, game_vertex_id = utils2.get_top_graph_ids(level_name)
local se_obj = alife():create(turret_section_name, position, level_vertex_id, game_vertex_id)

if se_obj == nil then
abort("can't create '%s' at (%f,%f,%f)")
end
-- лучше через table.concat()
local custom_data = "[logic]\nactive = turret\n[turret]\n"
if community ~= nil then
custom_data = custom_data.."community = "..community.."\n"
end
if owner_gulag ~= nil then
custom_data = custom_data.."owner_gulag = "..owner_gulag.."\n"
end
if hunt_actor_prob ~= nil then
custom_data = custom_data.."hunt_actor_prob = "..tostring(hunt_actor_prob).."\n"
else
custom_data = custom_data.."hunt_actor_prob = 50\n"
end
if search_dist ~= nil then
custom_data = custom_data.."search_dist = "..tostring(search_dist).."\n"
else
custom_data = custom_data.."search_dist = 90\n"
end
if explode_dist ~= nil then
custom_data = custom_data.."explode_dist = "..tostring(explode_dist).."\n"
else
custom_data = custom_data.."explode_dist = 3\n"
end
if spawner ~= nil then
custom_data = custom_data.."[spawner]\ncond = "..spawner.."\n"
end

se_obj:STATE_Write(packet1)

local dead_space = packet2:w_tell()

-- cse_alife_dynamic_object
utils2.packet_copy(packet2, packet1, 18)
packet1:r_stringZ()
packet2:w_stringZ(custom_data)
utils2.packet_copy(packet2, packet1, 8)
-- cse_visual
packet2:w_stringZ(packet1:r_stringZ())
utils2.packet_copy(packet2, packet1, 1)
-- cse_motion
packet2:w_stringZ(packet1:r_stringZ())
-- cse_ph_skeleton
packet2:w_stringZ(packet1:r_stringZ())
utils2.packet_copy(packet2, packet1, 3)
-- cse_alife_helicopter
packet2:w_stringZ("idle")
packet2:w_stringZ("$no_sound")
-- se_turret_mgun
packet2:w_float(1.0)

se_obj:STATE_Read(packet2, packet2:w_tell() - dead_space)

utils2.packet_pool_put(packet1)
utils2.packet_pool_put(packet2)

---------------direction
se_obj.direction = vector():set(-1, 0, 0)
---------------
end

-----------------------------------------------------------------------

class "se_turret_mgun" (cse_alife_helicopter)

function se_turret_mgun:__init(section) super(section)
self.spawner_present = false
self.health = 1.0
self.direction = vector():set(0, 0, 0)
end

function se_turret_mgun:can_switch_offline()
return cse_alife_helicopter.can_switch_offline(self)
end

function se_turret_mgun:can_switch_online()
if self.health <= 0.005 then
return false
end
if self.spawner_present == nil then
local ini = self:spawn_ini()
self.spawner_present = ini:section_exist("spawner")
end
if self.spawner_present == true then
return cse_alife_helicopter.can_switch_online(self)
end
return xr_spawner.check_spawn(self)
end   

function se_turret_mgun:STATE_Read(packet, size)
cse_alife_helicopter.STATE_Read(self, packet, size)
self.health = packet:r_float()
self.direction = packet:r_vec3()
end

function se_turret_mgun:STATE_Write(packet)
cse_alife_helicopter.STATE_Write(self, packet)
packet:w_float(self.health)
packet:w_vec3(self.direction)
end