## WeaponManager — client-side weapon inventory with rollback-safe firing.
##
## Manages weapon switching, ammo tracking. Firing is handled by the
## RollbackHitscanManager (in _rollback_tick) for lag compensation.
##
## This script is ONLY loaded from client scenes where netfox is active.

extends Node
class_name WeaponManager

signal weapon_switched(old_slot: int, new_slot: int, weapon_data: WeaponData)
signal ammo_changed(weapon_id: int, magazine: int, reserve: int)

# Preload the weapon scripts (only works when netfox is active)
const _HitscanWeapon := preload("res://client/weapons/scripts/tactical_weapon_hitscan.gd")

## Reference to the player's weapon anchor node.
@export var weapon_anchor: Node3D

## Reference to the RollbackHitscanManager (set by player).
var rollback_hitscan_mgr: Node = null

## Current weapon data.
var current_weapon: WeaponData = null
var current_weapon_node: Node3D = null
var current_slot: int = 1

## Inventory: slot → { data, node, magazine, reserve }
var _inventory: Dictionary = {}

var _last_fire_time: float = 0.0

func add_weapon(data: WeaponData) -> void:
	var slot: int = data.slot
	if _inventory.has(slot):
		_remove_weapon(slot)

	var weapon_node: Node3D = _create_weapon(data)
	if weapon_node == null:
		return
	weapon_node.visible = false
	add_child(weapon_node)

	_inventory[slot] = {
		"data": data,
		"node": weapon_node,
		"magazine": data.magazine_size,
		"reserve": data.reserve_size,
	}

	if current_weapon == null:
		switch_to_slot(slot)

func remove_weapon(slot: int) -> void:
	_remove_weapon(slot)
	if current_slot == slot:
		_switch_to_next_available()

func switch_to_slot(slot: int) -> bool:
	if not _inventory.has(slot):
		return false
	var entry = _inventory[slot]
	var old_slot := current_slot
	current_slot = slot
	current_weapon = entry["data"] as WeaponData
	current_weapon_node = entry["node"] as Node3D
	_update_visibility()
	weapon_switched.emit(old_slot, slot, current_weapon)

	# Update the RollbackHitscanManager with the new weapon data
	_notify_hitscan_mgr_of_weapon_change(current_weapon)
	return true

func switch_next() -> void:
	var slots := _inventory.keys()
	slots.sort()
	var idx := slots.find(current_slot)
	if idx >= 0 and idx + 1 < slots.size():
		switch_to_slot(slots[idx + 1])

func switch_prev() -> void:
	var slots := _inventory.keys()
	slots.sort()
	var idx := slots.find(current_slot)
	if idx > 0:
		switch_to_slot(slots[idx - 1])

# ---------------------------------------------------------------------------
# Firing (rollback-safe — delegates to RollbackHitscanManager)
# ---------------------------------------------------------------------------

## Called by the client to attempt firing through the rollback system.
## Returns true if ammo was consumed.
func fire() -> bool:
	if current_weapon_node == null or current_weapon == null:
		return false
	if current_weapon.magazine_size > 0 and _get_magazine() <= 0:
		return false
	if not _check_fire_rate():
		return false

	# Consume ammo immediately for client prediction
	var entry = _inventory[current_slot]
	entry["magazine"] -= 1
	ammo_changed.emit(current_weapon.weapon_id, entry["magazine"], entry["reserve"])
	_last_fire_time = Time.get_ticks_msec() / 1000.0

	# The actual raycast and damage happen in the RollbackHitscanManager's
	# process_fire() during _rollback_tick(), triggered by the shoot input.
	# This method just handles the client-side ammo tracking.
	return true

func reload() -> void:
	if current_weapon == null or current_weapon.magazine_size <= 0:
		return
	var entry = _inventory[current_slot]
	if entry["magazine"] >= current_weapon.magazine_size or entry["reserve"] <= 0:
		return
	var needed := current_weapon.magazine_size - entry["magazine"]
	var available := min(needed, entry["reserve"])
	entry["magazine"] += available
	entry["reserve"] -= available
	ammo_changed.emit(current_weapon.weapon_id, entry["magazine"], entry["reserve"])

func get_ammo() -> Vector2i:
	if current_weapon == null or not _inventory.has(current_slot):
		return Vector2i.ZERO
	var e = _inventory[current_slot]
	return Vector2i(e["magazine"], e["reserve"])

## Get the current weapon's maximum distance for raycasting.
func get_max_distance() -> float:
	if current_weapon != null:
		return current_weapon.max_distance
	return 1000.0

## Get the current weapon ID.
func get_weapon_id() -> int:
	if current_weapon != null:
		return current_weapon.weapon_id
	return 0

func get_current_weapon_data() -> WeaponData:
	return current_weapon

# ---------------------------------------------------------------------------
# Rollback integration
# ---------------------------------------------------------------------------

## Notify the RollbackHitscanManager when the weapon changes.
func _notify_hitscan_mgr_of_weapon_change(wd: WeaponData) -> void:
	if rollback_hitscan_mgr != null and rollback_hitscan_mgr.has_method(&"set_weapon_data"):
		rollback_hitscan_mgr.set_weapon_data(wd)

# ---------------------------------------------------------------------------
# Internal
# ---------------------------------------------------------------------------

func _create_weapon(data: WeaponData) -> Node3D:
	var weapon := Node3D.new()
	weapon.name = data.weapon_name

	if data.fire_mode != WeaponData.FireMode.MELEE:
		var hs: TacticalWeaponHitscan = _HitscanWeapon.new()
		hs.name = "Hitscan"
		hs.weapon_data = data
		hs.max_distance = data.max_distance
		weapon.add_child(hs, true)

	return weapon

func _get_magazine() -> int:
	var e = _inventory.get(current_slot)
	return e["magazine"] if e else 0

func _check_fire_rate() -> bool:
	if current_weapon.fire_rate <= 0:
		return false
	var now := Time.get_ticks_msec() / 1000.0
	return (now - _last_fire_time) >= (1.0 / current_weapon.fire_rate)

func _remove_weapon(slot: int) -> void:
	var e = _inventory.get(slot)
	if e and e["node"]:
		e["node"].queue_free()
	_inventory.erase(slot)

func _switch_to_next_available() -> void:
	var slots := _inventory.keys()
	slots.sort()
	if slots.size() > 0:
		switch_to_slot(slots[0])
	else:
		current_weapon = null
		current_weapon_node = null
		_update_visibility()

func _update_visibility() -> void:
	for slot in _inventory:
		_inventory[slot]["node"].visible = (slot == current_slot)