class_name ServerLog
extends RefCounted

# Structured server logging (multiplayer-next.md task 6.4).
#
# Extracted from server_boot.gd's private `_log`, which could only ever see
# what the boot scene itself observed: connects, disconnects, roster changes
# and tick overruns. The events an operator actually asks about — who scored,
# who got kicked and why, which peer is flooding — happen inside
# networked_match.gd and match_sim.gd, neither of which could reach a logger
# living on a scene node that gets freed at the first change_scene_to_file.
# Static state on a class_name is reachable from all three with no autoload
# and no ordering dependency.
#
# Format: `[<seconds since boot>] LEVEL event key=value key=value`. One line
# per event, no wrapping, no multi-line payloads, keys before values — so
# `grep 'player_joined'` and `awk` both work on it without a parser.
#
# ROTATION IS DELIBERATELY NOT IMPLEMENTED HERE. The server logs to stdout and
# stops there, because every way this is actually run already owns log
# rotation and does it better: `docker logs` with its json-file driver's
# max-size/max-file, journald under the systemd unit, or a redirect into
# logrotate for a bare process. A server that also writes and rotates its own
# file would duplicate all of that and fight it in a container, where stdout is
# the interface. SERVER.md documents the three configurations; task 6.6 ships
# them. Godot's own `debug/file_logging` remains available for anyone who wants
# a file as well, and it rotates via `max_log_files`.

const LEVELS := {"debug": 0, "info": 1, "warn": 2, "error": 3}

static var _level := 1          # info
static var _boot_ms := -1
static var _enabled := false    # servers only; a client process logs nothing


# Called once by the process that owns the command line. Until then nothing is
# emitted at all — a client, an editor session or a unit-test run must not
# start printing server telemetry just because it loaded these scripts.
static func configure(level_name: String) -> void:
	_level = int(LEVELS.get(level_name, 1))
	_boot_ms = Time.get_ticks_msec()
	_enabled = true


static func is_enabled() -> bool:
	return _enabled


static func level_name() -> String:
	for key in LEVELS:
		if int(LEVELS[key]) == _level:
			return key
	return "info"


static func debug(event: String, fields: Dictionary = {}) -> void:
	_write("debug", event, fields)


static func info(event: String, fields: Dictionary = {}) -> void:
	_write("info", event, fields)


static func warn(event: String, fields: Dictionary = {}) -> void:
	_write("warn", event, fields)


static func error(event: String, fields: Dictionary = {}) -> void:
	_write("error", event, fields)


static func _write(level: String, event: String, fields: Dictionary) -> void:
	if not _enabled:
		return
	if int(LEVELS.get(level, 1)) < _level:
		return
	var parts := PackedStringArray()
	for key in fields:
		parts.append("%s=%s" % [key, _flatten(fields[key])])
	var elapsed_sec := float(Time.get_ticks_msec() - _boot_ms) / 1000.0
	print("[%.3f] %s %s %s" % [elapsed_sec, level.to_upper(), event, " ".join(parts)])


# One line per event is the whole contract, so a value containing a space or a
# newline would break every downstream `awk '{print $4}'`. Quote rather than
# silently mangle: a player name is operator-supplied and can contain anything.
static func _flatten(value: Variant) -> String:
	var text := str(value)
	text = text.replace("\n", "\\n").replace("\r", "\\r")
	if " " in text or text.is_empty():
		return "\"%s\"" % text.replace("\"", "'")
	return text