extends Node

# Autoload (project.godot [autoload] MatchSim). Phase 2 simulation RPCs:
# match_config (server assigns arena + deterministic slot order from
# MatchNet.roster), input (client -> server, per-tick action), snapshot
# (server -> client, NetCodec-packed body state), and a small score_update
# for the HUD. Lives on an autoload per §1.3's derived decision ("All
# hot-path RPCs live on autoloads") even though these are scoped to
# whichever match happens to be running — a scene-node RPC target would
# need matching NodePaths across peers, which an autoload sidesteps
# entirely, and it's what lets NetworkedMatch itself stay a plain scene
# node with no networking-identity concerns of its own.
#
# Channel intent per §2.1: 0 reliable (match_config, score_update), 1
# unreliable-ordered (input), 2 unreliable-ordered (snapshot) — not yet
# verified against ENet's own reserved system channel offset (§2.1's own
# "verify empirically" hedge); if that turns out to matter these indices
# will need adjusting, not the RPC design itself.

const NetCodec = preload("res://scripts/net_codec.gd")

signal match_config_received(arena_path: String, peer_ids: PackedInt32Array, teams: PackedInt32Array, spawn_indices: PackedInt32Array)
signal input_received(peer_id: int, decoded: Dictionary)    # decoded: see NetCodec.unpack_input
signal snapshot_received(decoded: Dictionary)                # decoded: see NetCodec.unpack_snapshot
signal score_update_received(score: Dictionary)

# Server only: the last match_config actually sent, so a client whose own
# scene load (and therefore its match_config_received listener) finishes
# AFTER the server already broadcast can still get it — a one-shot
# broadcast alone is racy against however long the client takes to reach
# the point where it's listening, and Godot signals never buffer for a
# late connection. request_match_config() closes that race by turning
# delivery into "ask until you get it" instead of "hope you were already
# listening." Also covers a late joiner mid-match (Phase 5 will still need
# to add live match *state*, not just this static config, for that case).
var _last_match_config: Dictionary = {}


func send_match_config(arena_path: String, peer_ids: PackedInt32Array, teams: PackedInt32Array, spawn_indices: PackedInt32Array) -> void:
	_last_match_config = {
		"arena_path": arena_path, "peer_ids": peer_ids, "teams": teams, "spawn_indices": spawn_indices,
	}
	_match_config.rpc(arena_path, peer_ids, teams, spawn_indices)


func request_match_config() -> void:
	_request_match_config.rpc_id(1)


func send_input(bytes: PackedByteArray) -> void:
	# bytes is already fully packed (any timestamps it carries are already
	# fixed), so wrapping the dispatch itself is enough — task 2.8.
	NetSim.send(func() -> void: _recv_input.rpc_id(1, bytes), 1)


func send_snapshot(peer_id: int, bytes: PackedByteArray) -> void:
	NetSim.send(func() -> void: _snapshot.rpc_id(peer_id, bytes), peer_id)


func send_score_update(score: Dictionary) -> void:
	_score_update.rpc(score)


@rpc("authority", "call_remote", "reliable", 0)
func _match_config(arena_path: String, peer_ids: PackedInt32Array, teams: PackedInt32Array, spawn_indices: PackedInt32Array) -> void:
	match_config_received.emit(arena_path, peer_ids, teams, spawn_indices)


@rpc("any_peer", "call_remote", "reliable", 0)
func _request_match_config() -> void:
	if not multiplayer.is_server() or _last_match_config.is_empty():
		return
	var peer_id := multiplayer.get_remote_sender_id()
	_match_config.rpc_id(
		peer_id, _last_match_config["arena_path"], _last_match_config["peer_ids"],
		_last_match_config["teams"], _last_match_config["spawn_indices"]
	)


@rpc("any_peer", "call_remote", "unreliable_ordered", 1)
func _recv_input(bytes: PackedByteArray) -> void:
	if not multiplayer.is_server():
		return
	var peer_id := multiplayer.get_remote_sender_id()
	var decoded := NetCodec.unpack_input(bytes)
	input_received.emit(peer_id, decoded)


@rpc("authority", "call_remote", "unreliable_ordered", 2)
func _snapshot(bytes: PackedByteArray) -> void:
	var decoded := NetCodec.unpack_snapshot(bytes)
	snapshot_received.emit(decoded)


@rpc("authority", "call_remote", "reliable", 0)
func _score_update(score: Dictionary) -> void:
	score_update_received.emit(score)