//** Shield Helpers
//These are shared by various items that have shield-like behaviour

//bad_arc is the ABSOLUTE arc of directions from which we cannot block. If you want to fix it to e.g. the user's facing you will need to rotate the dirs yourself.
/proc/check_shield_arc(mob/user, var/bad_arc, atom/damage_source = null, mob/attacker = null)
	//check attack direction
	var/attack_dir = 0 //direction from the user to the source of the attack
	if(istype(damage_source, /obj/item/projectile))
		var/obj/item/projectile/P = damage_source
		attack_dir = get_dir(get_turf(user), P.starting)
	else if(attacker)
		attack_dir = get_dir(get_turf(user), get_turf(attacker))
	else if(damage_source)
		attack_dir = get_dir(get_turf(user), get_turf(damage_source))

	if(!(attack_dir && (attack_dir & bad_arc)))
		return 1
	return 0

/proc/default_parry_check(mob/user, mob/attacker, atom/damage_source)
	//parry only melee attacks
	if(istype(damage_source, /obj/item/projectile) || (attacker && get_dist(user, attacker) > 1) || user.incapacitated())
		return 0

	//block as long as they are not directly behind us
	var/bad_arc = reverse_direction(user.dir) //arc of directions from which we cannot block
	if(!check_shield_arc(user, bad_arc, damage_source, attacker))
		return 0

	return 1

/obj/item/weapon/shield
	name = "shield"
	var/base_block_chance = 50

/obj/item/weapon/shield/handle_shield(mob/user, var/damage, atom/damage_source = null, mob/attacker = null, var/def_zone = null, var/attack_text = "the attack")
	if(user.incapacitated())
		return 0

	//block as long as they are not directly behind us
	var/bad_arc = reverse_direction(user.dir) //arc of directions from which we cannot block
	if(check_shield_arc(user, bad_arc, damage_source, attacker))
		if(prob(get_block_chance(user, damage, damage_source, attacker)))
			user.visible_message("<span class='danger'>\The [user] blocks [attack_text] with \the [src]!</span>")
			return 1
	return 0

/obj/item/weapon/shield/proc/get_block_chance(mob/user, var/damage, atom/damage_source = null, mob/attacker = null)
	return base_block_chance

/obj/item/weapon/shield/riot
	name = "riot shield"
	desc = "A shield adept at blocking blunt objects from connecting with the torso of the shield wielder."
	icon = 'icons/obj/weapons.dmi'
	icon_state = "riot"
	flags = CONDUCT
	slot_flags = SLOT_BACK
	force = 5.0
	throwforce = 5.0
	throw_speed = 1
	throw_range = 4
	w_class = 4.0
	origin_tech = list(TECH_MATERIAL = 2)
	matter = list("glass" = 7500, DEFAULT_WALL_MATERIAL = 1000)
	attack_verb = list("shoved", "bashed")
	var/cooldown = 0 //shield bash cooldown. based on world.time

/obj/item/weapon/shield/riot/handle_shield(mob/user)
	. = ..()
	if(.) playsound(user.loc, 'sound/weapons/Genhit.ogg', 50, 1)

/obj/item/weapon/shield/riot/get_block_chance(mob/user, var/damage, atom/damage_source = null, mob/attacker = null)
	if(istype(damage_source, /obj/item/projectile))
		var/obj/item/projectile/P = damage_source
		//plastic shields do not stop bullets or lasers, even in space. Will block beanbags, rubber bullets, and stunshots just fine though.
		if((is_sharp(P) && damage > 10) || istype(P, /obj/item/projectile/beam))
			return 0
	return base_block_chance

/obj/item/weapon/shield/riot/attackby(obj/item/weapon/W as obj, mob/user as mob)
	if(istype(W, /obj/item/weapon/melee/baton))
		if(cooldown < world.time - 25)
			user.visible_message("<span class='warning'>[user] bashes [src] with [W]!</span>")
			playsound(user.loc, 'sound/effects/shieldbash.ogg', 50, 1)
			cooldown = world.time
	else
		..()

/*
 * Energy Shield
 */

/obj/item/weapon/shield/energy
	name = "energy combat shield"
	desc = "A shield capable of stopping most projectile and melee attacks. It can be retracted, expanded, and stored anywhere."
	icon = 'icons/obj/weapons.dmi'
	icon_state = "eshield0" // eshield1 for expanded
	slot_flags = SLOT_EARS
	flags = CONDUCT
	force = 3.0
	throwforce = 5.0
	throw_speed = 1
	throw_range = 4
	w_class = 2
	origin_tech = list(TECH_MATERIAL = 4, TECH_MAGNET = 3, TECH_ILLEGAL = 4)
	attack_verb = list("shoved", "bashed")
	var/active = 0

/obj/item/weapon/shield/energy/handle_shield(mob/user)
	if(!active)
		return 0 //turn it on first!
	. = ..()

	if(.)
		var/datum/effect/effect/system/spark_spread/spark_system = PoolOrNew(/datum/effect/effect/system/spark_spread)
		spark_system.set_up(5, 0, user.loc)
		spark_system.start()
		playsound(user.loc, 'sound/weapons/blade1.ogg', 50, 1)

/obj/item/weapon/shield/energy/get_block_chance(mob/user, var/damage, atom/damage_source = null, mob/attacker = null)
	if(istype(damage_source, /obj/item/projectile))
		var/obj/item/projectile/P = damage_source
		if((is_sharp(P) && damage > 10) || istype(P, /obj/item/projectile/beam))
			return (base_block_chance - round(damage / 3)) //block bullets and beams using the old block chance
	return base_block_chance

/obj/item/weapon/shield/energy/attack_self(mob/living/user as mob)
	if ((CLUMSY in user.mutations) && prob(50))
		user << "<span class='warning'>You beat yourself in the head with [src].</span>"
		user.take_organ_damage(5)
	active = !active
	if (active)
		force = 10
		update_icon()
		w_class = 4
		slot_flags = null
		playsound(user, 'sound/weapons/saberon.ogg', 50, 1)
		user << "<span class='notice'>\The [src] is now active.</span>"

	else
		force = 3
		update_icon()
		w_class = 1
		slot_flags = SLOT_EARS
		playsound(user, 'sound/weapons/saberoff.ogg', 50, 1)
		user << "<span class='notice'>\The [src] can now be concealed.</span>"

	if(istype(user,/mob/living/carbon/human))
		var/mob/living/carbon/human/H = user
		H.update_inv_l_hand()
		H.update_inv_r_hand()

	add_fingerprint(user)
	return

/obj/item/weapon/shield/energy/update_icon()
	icon_state = "eshield[active]"
	if(active)
		set_light(1.5, 1.5, "#006AFF")
	else
		set_light(0)

/obj/item/weapon/cloaking_device
	name = "cloaking device"
	desc = "Use this to become invisible to the human eye."
	icon = 'icons/obj/device.dmi'
	icon_state = "shield0"
	var/active = 0.0
	flags = CONDUCT
	item_state = "electronic"
	throwforce = 10.0
	throw_speed = 2
	throw_range = 10
	w_class = 2.0
	origin_tech = list(TECH_MAGNET = 3, TECH_ILLEGAL = 4)


/obj/item/weapon/cloaking_device/attack_self(mob/user as mob)
	src.active = !( src.active )
	if (src.active)
		user << "<span class='notice'>\The [src] is now active.</span>"
		src.icon_state = "shield1"
	else
		user << "<span class='notice'>\The [src] is now inactive.</span>"
		src.icon_state = "shield0"
	src.add_fingerprint(user)
	return

/obj/item/weapon/cloaking_device/emp_act(severity)
	active = 0
	icon_state = "shield0"
	if(ismob(loc))
		loc:update_icons()
	..()

/obj/item/weapon/shield/riot/tele
	name = "telescopic shield"
	desc = "An advanced riot shield made of lightweight materials that collapses for easy storage."
	icon = 'icons/obj/weapons.dmi'
	icon_state = "teleriot0"
	slot_flags = null
	force = 3
	throwforce = 3
	throw_speed = 3
	throw_range = 4
	w_class = 3
	var/active = 0
/*
/obj/item/weapon/shield/energy/IsShield()
	if(active)
		return 1
	else
		return 0
*/
/obj/item/weapon/shield/riot/tele/attack_self(mob/living/user)
	active = !active
	icon_state = "teleriot[active]"
	playsound(src.loc, 'sound/weapons/empty.ogg', 50, 1)

	if(active)
		force = 8
		throwforce = 5
		throw_speed = 2
		w_class = 4
		slot_flags = SLOT_BACK
		user << "<span class='notice'>You extend \the [src].</span>"
	else
		force = 3
		throwforce = 3
		throw_speed = 3
		w_class = 3
		slot_flags = null
		user << "<span class='notice'>[src] can now be concealed.</span>"

	if(istype(user,/mob/living/carbon/human))
		var/mob/living/carbon/human/H = user
		H.update_inv_l_hand()
		H.update_inv_r_hand()

	add_fingerprint(user)
	return