Bubberstation/code/modules/vehicles/mecha/combat/durand.dm

/obj/vehicle/sealed/mecha/durand
	desc = "An aging combat exosuit utilized by the Nanotrasen corporation. Originally developed to combat hostile alien lifeforms."
	name = "\improper Durand"
	icon_state = "durand"
	base_icon_state = "durand"
	movedelay = 4
	max_integrity = 400
	accesses = list(ACCESS_MECH_SCIENCE, ACCESS_MECH_SECURITY)
	armor_type = /datum/armor/mecha_durand
	max_temperature = 30000
	force = 40
	destruction_sleep_duration = 40
	exit_delay = 40
	wreckage = /obj/structure/mecha_wreckage/durand
	mech_type = EXOSUIT_MODULE_DURAND
	max_equip_by_category = list(
		MECHA_L_ARM = 1,
		MECHA_R_ARM = 1,
		MECHA_UTILITY = 3,
		MECHA_POWER = 1,
		MECHA_ARMOR = 1,
	)
	var/obj/durand_shield/shield

/datum/armor/mecha_durand
	melee = 40
	bullet = 35
	laser = 15
	energy = 10
	bomb = 20
	fire = 100
	acid = 100

/obj/vehicle/sealed/mecha/durand/Initialize(mapload)
	. = ..()
	shield = new /obj/durand_shield(loc, src, plane, layer, dir)
	RegisterSignal(src, COMSIG_MECHA_ACTION_TRIGGER, PROC_REF(relay))

/obj/vehicle/sealed/mecha/durand/Destroy()
	if(shield)
		QDEL_NULL(shield)
	return ..()


/obj/vehicle/sealed/mecha/durand/generate_actions()
	. = ..()
	initialize_passenger_action_type(/datum/action/vehicle/sealed/mecha/mech_defense_mode)

/obj/vehicle/sealed/mecha/durand/process()
	. = ..()
	if(defense_mode && !use_energy(0.01 * STANDARD_CELL_CHARGE)) //Defence mode can only be on with a occupant so we check if one of them can toggle it and toggle
		for(var/O in occupants)
			var/mob/living/occupant = O
			var/datum/action/action = LAZYACCESSASSOC(occupant_actions, occupant, /datum/action/vehicle/sealed/mecha/mech_defense_mode)
			if(action)
				action.Trigger()
				break

/obj/vehicle/sealed/mecha/durand/Move(direction)
	. = ..()
	if(shield)
		shield.forceMove(loc)
		shield.setDir(dir)

/obj/vehicle/sealed/mecha/durand/forceMove(turf/T)
	. = ..()
	shield.forceMove(T)

/obj/vehicle/sealed/mecha/durand/mob_exit(mob/M, silent = FALSE, randomstep = FALSE, forced = FALSE)
	if(defense_mode)
		var/datum/action/action = LAZYACCESSASSOC(occupant_actions, M, /datum/action/vehicle/sealed/mecha/mech_defense_mode)
		if(action)
			INVOKE_ASYNC(action, TYPE_PROC_REF(/datum/action, Trigger), null, NONE, FALSE)
	return ..()

///Relays the signal from the action button to the shield, and creates a new shield if the old one is MIA.
/obj/vehicle/sealed/mecha/durand/proc/relay(datum/source, mob/owner, list/signal_args)
	SIGNAL_HANDLER
	if(!shield) //if the shield somehow got deleted
		stack_trace("Durand triggered relay without a shield")
		shield = new /obj/durand_shield(loc, src, layer)
	shield.setDir(dir)

//Redirects projectiles to the shield if defense_check decides they should be blocked and returns true.
/obj/vehicle/sealed/mecha/durand/projectile_hit(obj/projectile/hitting_projectile, def_zone, piercing_hit, blocked)
	if(defense_check(hitting_projectile.loc) && shield)
		return shield.projectile_hit(hitting_projectile, def_zone, piercing_hit, blocked)
	return ..()

/**Checks if defense mode is enabled, and if the attacker is standing in an area covered by the shield.
Expects a turf. Returns true if the attack should be blocked, false if not.*/
/obj/vehicle/sealed/mecha/durand/proc/defense_check(turf/aloc)
	if (!defense_mode || !shield || shield.switching)
		return FALSE
	. = FALSE
	switch(dir)
		if (1)
			if(abs(x - aloc.x) <= (y - aloc.y) * -2)
				. = TRUE
		if (2)
			if(abs(x - aloc.x) <= (y - aloc.y) * 2)
				. = TRUE
		if (4)
			if(abs(y - aloc.y) <= (x - aloc.x) * -2)
				. = TRUE
		if (8)
			if(abs(y - aloc.y) <= (x - aloc.x) * 2)
				. = TRUE
	return

/obj/vehicle/sealed/mecha/durand/attack_generic(mob/user, damage_amount = 0, damage_type = BRUTE, damage_flag = 0, sound_effect = 1, armor_penetration = 0)
	if(defense_check(user.loc))
		log_message("Attack absorbed by defense field. Attacker - [user].", LOG_MECHA, color="orange")
		return shield.attack_generic(user, damage_amount, damage_type, damage_flag, sound_effect, armor_penetration)
	return ..()

/obj/vehicle/sealed/mecha/durand/blob_act(obj/structure/blob/B)
	if(defense_check(B.loc))
		log_message("Attack by blob. Attacker - [B].", LOG_MECHA, color="red")
		log_message("Attack absorbed by defense field.", LOG_MECHA, color="orange")
		shield.blob_act(B)
	else
		. = ..()

/obj/vehicle/sealed/mecha/durand/attackby(obj/item/W as obj, mob/user as mob, list/modifiers, list/attack_modifiers)
	if(defense_check(user.loc))
		log_message("Attack absorbed by defense field. Attacker - [user], with [W]", LOG_MECHA, color="orange")
		shield.attackby(W, user, modifiers)
	else
		. = ..()

/obj/vehicle/sealed/mecha/durand/hitby(atom/movable/AM, skipcatch, hitpush, blocked, datum/thrownthing/throwingdatum)
	if(defense_check(AM.loc))
		log_message("Impact with [AM] absorbed by defense field.", LOG_MECHA, color="orange")
		shield.hitby(AM, skipcatch, hitpush, blocked, throwingdatum)
	else
		. = ..()

/datum/action/vehicle/sealed/mecha/mech_defense_mode
	name = "Toggle an energy shield that blocks all attacks from the faced direction at a heavy power cost."
	button_icon_state = "mech_defense_mode_off"

/datum/action/vehicle/sealed/mecha/mech_defense_mode/Trigger(mob/clicker, trigger_flags, forced_state = FALSE)
	. = ..()
	if(!.)
		return
	if(!chassis || !(owner in chassis.occupants))
		return
	SEND_SIGNAL(chassis, COMSIG_MECHA_ACTION_TRIGGER, owner, args) //Signal sent to the mech, to be handed to the shield. See durand.dm for more details

////////////////////////////
///// Shield processing ////
////////////////////////////

/**An object to take the hit for us when using the Durand's defense mode.
It is spawned in during the durand's initilization, and always stays on the same tile.
Normally invisible, until defense mode is actvated. When the durand detects an attack that should be blocked, the
attack is passed to the shield. The shield takes the damage, uses it to calculate charge cost, and then sets its
own integrity back to max. Shield is automatically dropped if we run out of power or the user gets out.*/

/obj/durand_shield //projectiles get passed to this when defense mode is enabled
	name = "defense grid"
	icon = 'icons/mob/effects/durand_shield.dmi'
	icon_state = "shield_null"
	invisibility = INVISIBILITY_MAXIMUM //no showing on right-click
	pixel_y = 4
	max_integrity = 10000
	anchored = TRUE
	light_system = OVERLAY_LIGHT
	light_range = 2.8
	light_power = 1
	light_color = LIGHT_COLOR_FAINT_CYAN
	light_on = FALSE
	resistance_flags = LAVA_PROOF | FIRE_PROOF | ACID_PROOF //The shield should not take damage from fire,  lava, or acid; that's the mech's job.
	///Our link back to the durand
	var/obj/vehicle/sealed/mecha/durand/chassis
	///To keep track of things during the animation
	var/switching = FALSE

/obj/durand_shield/Initialize(mapload, chassis, plane, layer, dir)
	. = ..()
	src.chassis = chassis
	src.layer = ABOVE_MOB_LAYER
	SET_PLANE_IMPLICIT(src, plane)
	setDir(dir)
	RegisterSignal(chassis, COMSIG_MECHA_ACTION_TRIGGER, PROC_REF(activate))
	RegisterSignal(chassis, COMSIG_MOVABLE_UPDATE_GLIDE_SIZE, PROC_REF(shield_glide_size_update))

/obj/durand_shield/Destroy()
	UnregisterSignal(src, COMSIG_MECHA_ACTION_TRIGGER)
	if(chassis)
		UnregisterSignal(chassis, COMSIG_MOVABLE_UPDATE_GLIDE_SIZE)
		chassis.shield = null
		chassis = null
	return ..()

/obj/durand_shield/proc/shield_glide_size_update(datum/source, target)
	SIGNAL_HANDLER
	glide_size = target

/**
 * Handles activating and deactivating the shield.
 *
 * This proc is called by a signal sent from the mech's action button and
 * relayed by the mech itself. The "forced" variable, `signal_args[1]`, will
 * skip the to-pilot text and is meant for when the shield is disabled by
 * means other than the action button (like running out of power).
 *
 * Arguments:
 * * source: the shield
 * * owner: mob that activated the shield
 * * signal_args: whether it's forced
 */
/obj/durand_shield/proc/activate(datum/source, mob/owner, list/signal_args)
	SIGNAL_HANDLER
	if(!LAZYLEN(chassis?.occupants))
		return
	if(switching && !signal_args[1])
		return
	if(!chassis.defense_mode && (!chassis.cell || chassis.cell.charge < 100)) //If it's off, and we have less than 100 units of power
		chassis.balloon_alert(owner, "insufficient power")
		return
	switching = TRUE
	chassis.defense_mode = !chassis.defense_mode
	if(!signal_args[1])
		chassis.balloon_alert(owner, "shield [chassis.defense_mode?"enabled":"disabled"]")
		chassis.log_message("User has toggled defense mode -- now [chassis.defense_mode?"enabled":"disabled"].", LOG_MECHA)
	else
		chassis.log_message("defense mode state changed -- now [chassis.defense_mode?"enabled":"disabled"].", LOG_MECHA)
	for(var/occupant in chassis.occupants)
		var/datum/action/button = chassis.occupant_actions[occupant][/datum/action/vehicle/sealed/mecha/mech_defense_mode]
		button.button_icon_state = "mech_defense_mode_[chassis.defense_mode ? "on" : "off"]"
		button.build_all_button_icons()

	set_light_on(chassis.defense_mode)

	if(chassis.defense_mode)
		SetInvisibility(INVISIBILITY_NONE, id=type)
		flick("shield_raise", src)
		playsound(src, 'sound/vehicles/mecha/mech_shield_raise.ogg', 50, FALSE)
		icon_state = "shield"
		resetdir(chassis, dir, dir) // to set the plane for the shield properly when it's turned on
		RegisterSignal(chassis, COMSIG_ATOM_DIR_CHANGE, PROC_REF(resetdir))
	else
		flick("shield_drop", src)
		playsound(src, 'sound/vehicles/mecha/mech_shield_drop.ogg', 50, FALSE)
		icon_state = "shield_null"
		addtimer(CALLBACK(src, PROC_REF(make_invisible)), 1 SECONDS, TIMER_UNIQUE|TIMER_OVERRIDE)
		UnregisterSignal(chassis, COMSIG_ATOM_DIR_CHANGE)
	switching = FALSE

/**
 * Sets invisibility to INVISIBILITY_MAXIMUM if defense mode is disabled
 *
 * We need invisibility set to higher than 25 for the shield to not appear
 * in the right-click context menu, but if we do it too early, we miss the
 * deactivate animation. Hense, timer and this proc.
 */
/obj/durand_shield/proc/make_invisible()
	if(!chassis.defense_mode)
		RemoveInvisibility(type)

/obj/durand_shield/proc/resetdir(datum/source, olddir, newdir)
	SIGNAL_HANDLER

	setDir(newdir)

/obj/durand_shield/take_damage(damage_amount, damage_type = BRUTE, damage_flag = "", sound_effect = TRUE, attack_dir, armour_penetration = 0)
	if(!chassis)
		qdel(src)
		return
	if(!chassis.defense_mode) //if defense mode is disabled, we're taking damage that we shouldn't be taking
		return
	. = ..()
	flick("shield_impact", src)
	if(!.)
		return
	if(!chassis.use_energy(. * (STANDARD_CELL_CHARGE / 150)))
		chassis.cell?.charge = 0
		for(var/O in chassis.occupants)
			var/mob/living/occupant = O
			var/datum/action/action = LAZYACCESSASSOC(chassis.occupant_actions, occupant, /datum/action/vehicle/sealed/mecha/mech_defense_mode)
			action.Trigger()
	atom_integrity = 10000

/obj/durand_shield/play_attack_sound()
	playsound(src, 'sound/vehicles/mecha/mech_shield_deflect.ogg', 100, TRUE)

/obj/durand_shield/bullet_act()
	play_attack_sound()
	. = ..()