#define TURBINE_MAX_STORED_POWER (0.2 * STANDARD_CELL_CHARGE)
#define TURBINE_ANIMATION_TICKS_PER_TILE (1)
#define TURBINE_ANIMATION_TICKS (4)
#define TURBINE_CHARGE_PER_TILE (0.002 * STANDARD_CELL_CHARGE)
#define TURBINE_ANCHORED_POWER_PER_KPA (TURBINE_CHARGE_PER_TILE * 2)
#define TURBINE_MIN_SECONDS_BETWEEN_SOUNDS (0.33 SECONDS)

/obj/item/portable_wind_turbine
	name = "portable wind turbine"
	icon = 'icons/obj/wind_turbine.dmi'
	icon_state = "icon"
	base_icon_state = "icon"
	desc = "A portable wind turbine that can charge attached energy based weaponry, PDAs, and other devices. As a safety mechanism after an unprecedented amount of amputations, only charges when attached to your back / the floor."
	worn_icon = 'icons/obj/wind_turbine.dmi'
	worn_icon_state = "base_turbine"
	inhand_icon_state = "wind_turbine"
	lefthand_file = 'icons/mob/inhands/64x64_lefthand.dmi'
	righthand_file = 'icons/mob/inhands/64x64_righthand.dmi'
	inhand_x_dimension = 64
	inhand_y_dimension = 64
	slot_flags = ITEM_SLOT_SUITSTORE | ITEM_SLOT_BACK
	force = 10
	throwforce = 6
	w_class = WEIGHT_CLASS_BULKY
	custom_materials = list(/datum/material/iron = SHEET_MATERIAL_AMOUNT * 22, /datum/material/plastic = SHEET_MATERIAL_AMOUNT * 5, /datum/material/glass = SMALL_MATERIAL_AMOUNT * 0.5)
	///What item is being charged currently?
	var/obj/item/charging = null
	///Did we put power into "charging" last process()?
	var/using_power = FALSE

	///Current rotor animation frame. (floating point value).
	var/rotor_tick = 0
	///Power that has been generated by moving about.
	var/available_power = 0
	///The last time (world.time) a sound was played at.
	var/last_sound_time = 0
	///Capacitor currently inserted.
	var/obj/item/stock_parts/capacitor/cap = null

	var/static/list/allowed_devices = typecacheof(list(
		/obj/item/gun/energy,
		/obj/item/compact_remote,
		/obj/item/controller,
		/obj/item/organ/cyberimp/bci,
		/obj/item/integrated_circuit,
		/obj/item/melee/baton/security,
		/obj/item/modular_computer,
		/obj/item/stock_parts/power_store/cell,
	))

/obj/item/portable_wind_turbine/Initialize(mapload)
	. = ..()
	AddElement(/datum/element/drag_pickup)
	RegisterSignal(src, COMSIG_MOVABLE_SET_ANCHORED, PROC_REF(on_anchor))
	RegisterSignal(src, COMSIG_ATOM_PRE_DIR_CHANGE, PROC_REF(block_dir_changes_unanchored))
	update_appearance()

/obj/item/portable_wind_turbine/loaded/Initialize(mapload)
	. = ..()
	cap = new /obj/item/stock_parts/capacitor(src)

/obj/item/portable_wind_turbine/Destroy()
	return ..()

///Called when src is anchored
/obj/item/portable_wind_turbine/proc/on_anchor(atom/source, is_anchored)
	SIGNAL_HANDLER

	if (is_anchored)
		RegisterSignal(src, COMSIG_MOVABLE_RESISTED_SPACEWIND, PROC_REF(on_space_wind))
		UnregisterSignal(src, COMSIG_ATOM_PRE_DIR_CHANGE)
		forceMove(get_turf(src))
		pixel_x = 0
		pixel_y = 0
		setDir(SOUTH)
	else
		UnregisterSignal(src, COMSIG_MOVABLE_RESISTED_SPACEWIND)
		RegisterSignal(src, COMSIG_ATOM_PRE_DIR_CHANGE, PROC_REF(block_dir_changes_unanchored))

///Called when src changes direction when not equipped
/obj/item/portable_wind_turbine/proc/block_dir_changes_unanchored(atom/source, old_dir, new_dir)
	SIGNAL_HANDLER

	return COMPONENT_ATOM_BLOCK_DIR_CHANGE

///Called when this resists space wind
/obj/item/portable_wind_turbine/proc/on_space_wind(atom/source, pressure_difference, pressure_direction)
	SIGNAL_HANDLER

	var/obj/item/portable_wind_turbine/turbine = source
	if (!turbine)
		return
	if (isnull(cap))
		return
	turbine.add_power(TURBINE_ANCHORED_POWER_PER_KPA * pressure_difference * cap.rating, ignore_cap = TRUE)
	set_rotor_tick(rotor_tick + 1)

/obj/item/portable_wind_turbine/update_appearance(updates)
	. = ..()
	update_back()

/obj/item/portable_wind_turbine/equipped(mob/user, slot, initial)
	. = ..()
	update_appearance()
	if(slot & slot_flags)
		RegisterSignal(user, COMSIG_MOVABLE_MOVED, PROC_REF(on_move))
		RegisterSignal(user, COMSIG_ATOM_POST_DIR_CHANGE, PROC_REF(on_dir_change))
	else
		setDir(SOUTH)
		UnregisterSignal(user, COMSIG_MOVABLE_MOVED, PROC_REF(on_move))
		UnregisterSignal(user, COMSIG_ATOM_POST_DIR_CHANGE, PROC_REF(on_dir_change))

///Called when the thing HOLDING the turbine changes direction
/obj/item/portable_wind_turbine/proc/on_dir_change(datum/source, old_dir, new_dir)
	SIGNAL_HANDLER

	update_appearance()

///Updates the worn back icon for the current loc
/obj/item/portable_wind_turbine/proc/update_back()
	if (ishuman(loc))
		var/mob/living/carbon/human/human = loc
		human.update_worn_back()

///Tries to play the woosh sound effect. May not play it if it's been too soon since the last call.
/obj/item/portable_wind_turbine/proc/try_playsound()
	if ((world.time - last_sound_time) < TURBINE_MIN_SECONDS_BETWEEN_SOUNDS)
		return
	playsound(src, 'sound/machines/woosh.ogg', 20, FALSE)
	last_sound_time = world.time

///Sets the rotor animation tick to a new value. Returns TRUE if the rotor made a full rotation.
/obj/item/portable_wind_turbine/proc/set_rotor_tick(new_tick)
	var/last_rotor_tick = floor(rotor_tick)
	rotor_tick = new_tick
	var/made_full_rotation = FALSE
	if (rotor_tick >= TURBINE_ANIMATION_TICKS)
		rotor_tick -= floor(rotor_tick / TURBINE_ANIMATION_TICKS) * TURBINE_ANIMATION_TICKS
		try_playsound()
		made_full_rotation = TRUE
	var/rounded_rotor_tick = floor(rotor_tick)
	if (rounded_rotor_tick != last_rotor_tick)
		update_appearance()
	return made_full_rotation

///Adds a certain amount of power to the internal buffer
/obj/item/portable_wind_turbine/proc/add_power(power, ignore_cap = FALSE)
	if (ignore_cap)
		available_power += power
	else
		available_power = min(available_power + power, TURBINE_MAX_STORED_POWER * (isnull(cap?.rating) ?  1 : cap.rating))

///Called when the thing HOLDING the turbine moves
/obj/item/portable_wind_turbine/proc/on_move(atom/thing, atom/old_loc, dir)
	SIGNAL_HANDLER

	var/mob/living/user = thing
	if (!user)
		return
	if (isnull(cap))
		return
	var/distance = get_dist(old_loc, user.loc)
	var/turf/open/open_turf = get_turf(user)
	if (!istype(open_turf))
		return
	var/pressure_factor = open_turf.air.return_pressure() / 101.0
	if (pressure_factor <= 0)
		return
	var/made_full_rotation = set_rotor_tick(rotor_tick + distance * TURBINE_ANIMATION_TICKS_PER_TILE * pressure_factor)
	add_power(distance * TURBINE_CHARGE_PER_TILE * pressure_factor * cap.rating)
	if (!made_full_rotation)
		return
	if (!HAS_TRAIT(user, TRAIT_CLUMSY))
		return
	var/obj/item/bodypart/head/head_to_bash = user.get_bodypart(BODY_ZONE_HEAD)
	if (!head_to_bash)
		return
	user.Paralyze(5)
	user.Knockdown(10)
	user.visible_message(span_danger("[user] gets whacked in the head by the [src]'s spinning blades!"), span_userdanger("You get hit in the head by the [src] and fall over!"))
	// imaginary friends call sleep in their emotes
	// even though imaginary friends can't put on a wind turbine I still have to do this
	INVOKE_ASYNC(user, TYPE_PROC_REF(/mob/living/, emote), "scream")
	user.apply_damage(5, BRUTE, head_to_bash, attacking_item=src)
	playsound(source = src, soundin = 'sound/items/weapons/smash.ogg', vol = src.get_clamped_volume(), vary = TRUE)

/obj/item/portable_wind_turbine/wrench_act(mob/living/user, obj/item/tool)
	. = NONE
	switch(default_unfasten_wrench(user, tool, 4 SECONDS))
		if(SUCCESSFUL_UNFASTEN)
			return ITEM_INTERACT_SUCCESS
		if(FAILED_UNFASTEN)
			return ITEM_INTERACT_BLOCKING
	return .

/obj/item/portable_wind_turbine/examine(mob/user)
	. = ..()

	if(!in_range(user, src) && !issilicon(user) && !isobserver(user))
		. += span_warning("You're too far away to examine [src]'s contents! You can still watch it spin so wonderfully though...")
		if (charging && istype(charging,/obj/item/melee/baton/security/))
			. += span_info("You can see the [charging] hanging precariously off the charging port...")
		return

	if(cap)
		. += span_info("Click it with a screwdriver to eject the [cap].")
	. += span_info("Wrench it on a tile to anchor it and harness space wind.")
	. += span_info("The wind turbine is currently storing [floor(available_power / 100) / 10]kJ.")
	if(charging)
		. += {"[span_notice("\The [src] contains:")]
		[span_notice("- \A [charging].")]"}

/obj/item/portable_wind_turbine/screwdriver_act(mob/living/user, obj/item/tool)
	. = ..()
	if(charging)
		user.balloon_alert(user, "remove the [charging] first!")
		return FALSE
	if(cap)
		tool.play_tool_sound(src, 50)
		user.balloon_alert(user, "capacitor removed")
		cap.forceMove(drop_location())
		available_power = 0
		cap = null
		return TRUE
	else
		user.balloon_alert(user, "no capacitor!")
		return FALSE

/obj/item/portable_wind_turbine/Entered(atom/movable/arrived, atom/old_loc, list/atom/old_locs)
	if(is_type_in_typecache(arrived, allowed_devices))
		charging = arrived
		START_PROCESSING(SSmachines, src)
		using_power = TRUE
		update_appearance()
	return ..()

/obj/item/portable_wind_turbine/Exited(atom/movable/gone, direction)
	if(gone == charging)
		if(!QDELING(charging))
			charging.update_appearance()
		charging = null
		using_power = FALSE
		update_appearance()
	return ..()

/obj/item/portable_wind_turbine/attackby(obj/item/attacking_item, mob/user, params)
	if(istype(attacking_item, /obj/item/stock_parts/capacitor))
		if (cap)
			balloon_alert(user, "already has a capacitor!")
			return TRUE
		user.transferItemToLoc(attacking_item, src)
		cap = attacking_item
		balloon_alert(user, "inserted the [attacking_item]")
		return TRUE
	if(!is_type_in_typecache(attacking_item, allowed_devices))
		return ..()
	if(isnull(cap))
		balloon_alert(user, "no capacitor inserted!")
		return TRUE
	if(charging)
		balloon_alert(user, "already charging something!")
		return TRUE
	if(istype(attacking_item, /obj/item/gun/energy))
		var/obj/item/gun/energy/energy_gun = attacking_item
		if(!energy_gun.can_charge)
			balloon_alert(user, "not rechargable!")
			return TRUE
	user.transferItemToLoc(attacking_item, src)
	charging = attacking_item
	return TRUE

/obj/item/portable_wind_turbine/attack_hand(mob/user, list/modifiers)
	if(loc == user || (istype(loc, /turf) && !isnull(charging)))
		take_charging_out(user)
		return TRUE
	add_fingerprint(user)
	return ..()

/obj/item/portable_wind_turbine/handle_deconstruct(dissassembled)
	charging?.forceMove(drop_location())
	cap?.forceMove(drop_location())
	return ..()

///Takes charging item out if there is one
/obj/item/portable_wind_turbine/proc/take_charging_out(mob/user)
	if(isnull(charging) || user.put_in_hands(charging))
		return
	charging.forceMove(drop_location())
	update_appearance()

/obj/item/portable_wind_turbine/attack_tk(mob/user)
	if(isnull(charging))
		return
	charging.forceMove(drop_location())
	return COMPONENT_CANCEL_ATTACK_CHAIN

/obj/item/portable_wind_turbine/process(seconds_per_tick)
	using_power = FALSE
	if(isnull(charging))
		return PROCESS_KILL
	if(isnull(cap))
		// this is easier than starting/stopping the process based on capacitor state
		// this code only charges the attached item, so stopping it early should not be a problem
		return
	var/obj/item/stock_parts/power_store/cell/charging_cell = charging.get_cell()
	if (!charging_cell && istype(charging, /obj/item/stock_parts/power_store/cell))
		charging_cell = charging
	if (!charging_cell)
		var/datum/component/shell/shell = charging.GetComponent(/datum/component/shell)
		charging_cell = shell?.attached_circuit?.get_cell()
	if(charging_cell)
		var/wanted_power = min(charging_cell.maxcharge - charging_cell.charge, charging_cell.chargerate)
		if(wanted_power > 0)
			var/power_to_give = min(available_power, wanted_power) * seconds_per_tick / 2
			if (power_to_give > 0)
				charging_cell.give(power_to_give)
				available_power -= power_to_give
				if(charging_cell.charge == charging_cell.maxcharge)
					playsound(src, 'sound/machines/ping.ogg', 30, TRUE)
					say("[charging] has finished recharging!")
				else
					using_power = TRUE
		update_appearance()

/obj/item/portable_wind_turbine/emp_act(severity)
	. = ..()
	if (. & EMP_PROTECT_CONTENTS)
		return

	if(istype(charging, /obj/item/gun/energy))
		var/obj/item/gun/energy/energy_gun = charging
		energy_gun?.cell.emp_act(severity)

	else if(istype(charging, /obj/item/melee/baton/security))
		var/obj/item/melee/baton/security/batong = charging
		batong?.cell.charge = 0

/obj/item/portable_wind_turbine/update_overlays()
	. = ..()
	var/mutable_appearance/rotor = mutable_appearance(worn_icon, "rotor_[floor(rotor_tick)]")
	rotor.pixel_y -= 8
	. += rotor
	if (isnull(charging))
		return
	if (istype(charging, /obj/item/melee/baton/security/))
		. += mutable_appearance(icon, "baton")

/obj/item/portable_wind_turbine/worn_overlays(mutable_appearance/standing, isinhands, icon_file)
	. = ..()
	if (isinhands)
		return
	var/mutable_appearance/rotor = mutable_appearance(worn_icon, "rotor_[floor(rotor_tick)]")
	rotor.layer = BELOW_MOB_LAYER
	if (ishuman(loc))
		var/mob/living/carbon/human/user = loc
		if (user.dir & NORTH)
			var/mutable_appearance/just_render_above_other_things = mutable_appearance(worn_icon, worn_icon_state)
			just_render_above_other_things.layer = ABOVE_MOB_LAYER
			rotor.layer = ABOVE_MOB_LAYER
			. += just_render_above_other_things
	. += rotor
	if (isnull(charging))
		return
	if (istype(charging, /obj/item/melee/baton/security/))
		var/mutable_appearance/baton_overlay = mutable_appearance(icon, "baton")
		. += baton_overlay

#undef TURBINE_MAX_STORED_POWER
#undef TURBINE_ANIMATION_TICKS_PER_TILE
#undef TURBINE_ANIMATION_TICKS
#undef TURBINE_CHARGE_PER_TILE
#undef TURBINE_ANCHORED_POWER_PER_KPA
#undef TURBINE_MIN_SECONDS_BETWEEN_SOUNDS