/**
 * # Dispenser
 *
 * Immobile (but not dense) shell that can receive and dispense items.
 */
/obj/structure/dispenser_bot
	name = "dispenser"
	icon = 'icons/obj/science/circuits.dmi'
	icon_state = "setup_drone_arms"

	density = FALSE
	light_system = OVERLAY_LIGHT
	light_on = FALSE

	var/max_weight = WEIGHT_CLASS_NORMAL
	var/capacity = 20

	var/list/obj/item/stored_items = list()
	var/locked = FALSE

/obj/structure/dispenser_bot/atom_deconstruct(disassembled = TRUE)
	for(var/obj/item/stored_item as anything in stored_items)
		remove_item(stored_item)

/obj/structure/dispenser_bot/Destroy()
	QDEL_LIST(stored_items)
	return ..()


/obj/structure/dispenser_bot/proc/add_item(mob/user, obj/item/to_add)
	balloon_alert(user, "inserted item")
	stored_items += to_add
	to_add.forceMove(src)
	RegisterSignal(to_add, COMSIG_MOVABLE_MOVED, PROC_REF(handle_stored_item_moved))
	RegisterSignal(to_add, COMSIG_QDELETING, PROC_REF(handle_stored_item_deleted))
	SEND_SIGNAL(src, COMSIG_DISPENSERBOT_ADD_ITEM, to_add)

/obj/structure/dispenser_bot/proc/handle_stored_item_moved(obj/item/moving_item, atom/location)
	SIGNAL_HANDLER
	if(location != src)
		remove_item(moving_item)

/obj/structure/dispenser_bot/proc/handle_stored_item_deleted(obj/item/deleting_item)
	SIGNAL_HANDLER
	remove_item(deleting_item)

/obj/structure/dispenser_bot/proc/remove_item(obj/item/to_remove)
	UnregisterSignal(to_remove, list(
		COMSIG_MOVABLE_MOVED,
		COMSIG_QDELETING,
	))
	to_remove.forceMove(drop_location())
	stored_items -= to_remove
	SEND_SIGNAL(src, COMSIG_DISPENSERBOT_REMOVE_ITEM, to_remove)


/obj/structure/dispenser_bot/Initialize(mapload)
	. = ..()
	AddComponent(/datum/component/shell, list(
		new /obj/item/circuit_component/dispenser_bot()
	), SHELL_CAPACITY_LARGE)

/obj/structure/dispenser_bot/attackby(obj/item/item, mob/living/user, params)
	if(user.combat_mode)
		return ..()
	if(istype(item, /obj/item/wrench) || istype(item, /obj/item/multitool) || istype(item, /obj/item/integrated_circuit))
		return ..()
	if(item.w_class > max_weight && !istype(item, /obj/item/storage/bag))
		balloon_alert(user, "item too big!")
		return FALSE
	if(length(stored_items) >= capacity)
		balloon_alert(user, "at maximum capacity!")
		return FALSE
	if(istype(item, /obj/item/storage/bag))
		for(var/obj/item/bag_item in item.contents)
			if(length(stored_items) >= capacity)
				break
			if(bag_item.w_class > max_weight || istype(bag_item, /obj/item/storage/bag))
				continue
			add_item(user, bag_item)
		return TRUE
	add_item(user, item)
	return TRUE

/obj/structure/dispenser_bot/wrench_act(mob/living/user, obj/item/tool)
	if(locked)
		return
	set_anchored(!anchored)
	tool.play_tool_sound(src)
	balloon_alert(user, "[anchored? "secured" : "unsecured"]")
	return TRUE

/obj/item/circuit_component/dispenser_bot
	display_name = "Dispenser"
	desc = "A dispenser bot that can dispense items "

	/// The list of items
	var/datum/port/output/item_list
	/// The item that was added/removed.
	var/datum/port/output/item
	/// Called when an item is added.
	var/datum/port/output/on_item_added
	/// Called when an item is removed.
	var/datum/port/output/on_item_removed

	ui_buttons = list(
		"plus" = "add_vend_component",
	)

	/// Vendor components attached to this dispenser bot
	var/list/obj/item/circuit_component/vendor_component/vendor_components = list()

	var/max_vendor_components = 20


/obj/item/circuit_component/dispenser_bot/populate_ports()
	item_list = add_output_port("Items", PORT_TYPE_LIST(PORT_TYPE_ATOM))

	item = add_output_port("Item", PORT_TYPE_ATOM)
	on_item_added = add_output_port("On Item Added", PORT_TYPE_SIGNAL)
	on_item_removed = add_output_port("On Item Removed", PORT_TYPE_SIGNAL)

/obj/item/circuit_component/dispenser_bot/register_shell(atom/movable/shell)
	. = ..()
	RegisterSignal(shell, COMSIG_DISPENSERBOT_ADD_ITEM, PROC_REF(on_shell_add_item))
	RegisterSignal(shell, COMSIG_DISPENSERBOT_REMOVE_ITEM, PROC_REF(on_shell_remove_item))

/obj/item/circuit_component/dispenser_bot/unregister_shell(atom/movable/shell)
	UnregisterSignal(shell, list(
		COMSIG_DISPENSERBOT_ADD_ITEM,
		COMSIG_DISPENSERBOT_REMOVE_ITEM,
	))
	return ..()

/obj/item/circuit_component/dispenser_bot/proc/on_shell_add_item(obj/structure/dispenser_bot/source, obj/item/added_item)
	SIGNAL_HANDLER
	item.set_output(added_item)
	item_list.set_output(source.stored_items)
	on_item_added.set_output(COMPONENT_SIGNAL)

/obj/item/circuit_component/dispenser_bot/proc/on_shell_remove_item(obj/structure/dispenser_bot/source, obj/item/added_item)
	SIGNAL_HANDLER
	item.set_output(added_item)
	item_list.set_output(source.stored_items)
	on_item_added.set_output(COMPONENT_SIGNAL)

/obj/item/circuit_component/dispenser_bot/proc/remove_vendor_component(obj/item/circuit_component/vendor_component/vendor_component)
	SIGNAL_HANDLER
	UnregisterSignal(vendor_component, list(
		COMSIG_QDELETING,
		COMSIG_CIRCUIT_COMPONENT_REMOVED,
	))
	if(!QDELING(vendor_component))
		qdel(vendor_component)
	vendor_components -= vendor_component

/obj/item/circuit_component/dispenser_bot/ui_perform_action(mob/user, action)
	switch(action)
		if("add_vend_component")
			if(length(vendor_components) >= max_vendor_components)
				balloon_alert(user, "you have hit vendor component limit!")
				return
			var/obj/item/circuit_component/vendor_component/vendor_component = new(parent)
			parent.add_component(vendor_component, user)
			vendor_components += vendor_component
			RegisterSignals(vendor_component, list(
				COMSIG_QDELETING,
				COMSIG_CIRCUIT_COMPONENT_REMOVED,
			), PROC_REF(remove_vendor_component))

/obj/item/circuit_component/vendor_component
	display_name = "Vend"
	desc = "A component used to vend out specific objects from the dispenser bot."

	circuit_flags = CIRCUIT_FLAG_OUTPUT_SIGNAL

	var/obj/structure/dispenser_bot/attached_bot

	/// The item this vendor component should vend
	var/datum/port/input/item_to_vend
	/// Used to vend the item
	var/datum/port/input/vend_item

	circuit_size = 0

/obj/item/circuit_component/vendor_component/register_shell(atom/movable/shell)
	. = ..()
	if(istype(shell, /obj/structure/dispenser_bot))
		attached_bot = shell

/obj/item/circuit_component/vendor_component/unregister_shell(atom/movable/shell)
	attached_bot = null
	return ..()

/obj/item/circuit_component/vendor_component/populate_ports()
	item_to_vend = add_input_port("Item", PORT_TYPE_ATOM, trigger = null)
	vend_item = add_input_port("Vend Item", PORT_TYPE_SIGNAL, trigger = PROC_REF(vend_item))

/obj/item/circuit_component/vendor_component/proc/vend_item(datum/port/input/port, list/return_values)
	CIRCUIT_TRIGGER
	if(!attached_bot)
		return

	var/obj/item/vending_item = locate(item_to_vend.value) in attached_bot.stored_items

	if(!vending_item)
		return

	attached_bot.remove_item(vending_item)