extends RefCounted
## A dedicated server's preferences (`server.json`) and its reserved names
## (`names.json` alongside). Created with defaults on first run and meant to
## be edited by hand; command-line flags override single values for one run.
## See docs/MULTIPLAYER_PLAN.md §4.

const DEFAULT_PATH := "user://server/server.json"
const DEFAULTS := {
	"server_name": "Emberwild server",
	"motd": "Welcome!",
	"port": 24242,
	"max_players": 8,
	"password": "",
	"world": "server-world",
	"worldlet": "valley",
	"seed": 1337,
	"pvp": false,
	"raiding": false,
	"locks": "owner_and_friends",
	"death_penalty": "grave",
	"sleep": "all_online",
	"pause_when_empty": true,
	"day_length_minutes": 20,
	"wolf_grace_days": 3,
	"difficulty": "normal",
	"rot": "normal",
	"autosave_minutes": 2,
	"backups_kept": 10,
	"backup_hours": 6,
	"check_updates": true,
	"admins": [],
	"allowlist": [],
	"banned": [],
}
## Settings sent to players when they join (never the password or the lists).
const PUBLIC := ["server_name", "motd", "max_players", "worldlet", "pvp", "raiding", "locks",
	"death_penalty", "sleep", "pause_when_empty", "day_length_minutes", "wolf_grace_days", "difficulty", "rot"]

var path := DEFAULT_PATH
var data: Dictionary = {}          ## what's in server.json (saved)
var overrides: Dictionary = {}     ## command-line flags for this run (never saved)
## Reserved names: lower-case name -> {"name": as typed, "id": player id}.
var names: Dictionary = {}

static func open(p: String = DEFAULT_PATH) -> RefCounted:
	var c = load("res://scripts/net/server_config.gd").new()
	c.path = p
	DirAccess.make_dir_recursive_absolute(p.get_base_dir())
	var loaded: Variant = JSON.parse_string(FileAccess.get_file_as_string(p)) if FileAccess.file_exists(p) else null
	c.data = DEFAULTS.duplicate(true)
	if loaded is Dictionary:
		for k in loaded:
			c.data[k] = loaded[k]
	else:
		c.save()   # first run: write the defaults so they can be edited
	var n: Variant = JSON.parse_string(FileAccess.get_file_as_string(c.names_path())) \
		if FileAccess.file_exists(c.names_path()) else null
	if n is Dictionary:
		c.names = n
	c.load_friends()
	return c

func names_path() -> String:
	return path.get_base_dir().path_join("names.json")

func save() -> void:
	_write(path, data)

func save_names() -> void:
	_write(names_path(), names)

static func _write(p: String, d: Dictionary) -> void:
	var tmp := p + ".tmp"
	var f := FileAccess.open(tmp, FileAccess.WRITE)
	if f == null:
		push_error("[server] couldn't write %s" % p)
		return
	f.store_string(JSON.stringify(d, "\t"))
	f.close()
	DirAccess.rename_absolute(tmp, p)

## A setting's value for this run (a flag beats the file).
func v(k: String) -> Variant:
	return overrides.get(k, data.get(k))

func public_info() -> Dictionary:
	var out := {}
	for k in PUBLIC:
		out[k] = v(k)
	return out

## The player id holding `n`, or "" if it's free.
func name_owner(n: String) -> String:
	return String(names.get(n.to_lower(), {}).get("id", ""))

## Gives `n` to `id`, releasing any other name that id held.
func reserve_name(n: String, id: String) -> void:
	for k in names.keys():
		if names[k].id == id and k != n.to_lower():
			names.erase(k)
	names[n.to_lower()] = {"name": n, "id": id}
	save_names()

func is_admin(id: String) -> bool:
	return id in data.admins

func add_admin(id: String) -> void:
	if not id in data.admins:
		data.admins.append(id)
		save()

func ban(id: String) -> void:
	if not id in data.banned:
		data.banned.append(id)
		save()

func unban(id: String) -> bool:
	if not id in data.banned:
		return false
	data.banned.erase(id)
	save()
	return true

## A reserved name back up for grabs (the player who had it keeps their
## character, and picks another name next time they join).
func release_name(n: String) -> bool:
	if not names.has(n.to_lower()):
		return false
	names.erase(n.to_lower())
	save_names()
	return true

## The name a player id goes by here ("" if none).
func name_of(id: String) -> String:
	for k in names:
		if names[k].id == id:
			return String(names[k].name)
	return ""

# --- rules that can change while the server runs (/set) --------------------------

## What each can be set to. The others in DEFAULTS are fixed at start-up.
const SETTABLE := {
	"pvp": ["false", "true"],
	"raiding": ["false", "true"],
	"locks": ["off", "owner", "owner_and_friends"],
	"death_penalty": ["grave", "keep", "drop_all"],
	"sleep": ["all_online", "half", "anyone", "off"],
	"pause_when_empty": ["false", "true"],
	"difficulty": ["easy", "normal", "hard"],
	"rot": ["normal", "slow", "off"],
	"wolf_grace_days": "0-10",
	"motd": "text",
	"server_name": "text",
}

## Changes a rule and saves server.json. Returns "" or what's wrong.
func set_rule(k: String, value: String) -> String:
	if not SETTABLE.has(k):
		return "Can't set '%s'. These can be set: %s" % [k, ", ".join(PackedStringArray(SETTABLE.keys()))]
	var allowed: Variant = SETTABLE[k]
	var val: Variant
	if allowed is Array:
		if not value in allowed:
			return "%s can be: %s" % [k, " / ".join(PackedStringArray(allowed))]
		val = (value == "true") if value in ["true", "false"] else value
	elif allowed == "0-10":
		if not value.is_valid_int() or int(value) < 0 or int(value) > 10:
			return "%s is a number from 0 to 10" % k
		val = int(value)
	else:
		if value.strip_edges().is_empty() or value.length() > 80:
			return "%s needs some text (up to 80 characters)" % k
		val = value.strip_edges()
	data[k] = val
	overrides.erase(k)   # (a flag no longer wins over what the admin just set)
	save()
	return ""

# --- friends (docs/MULTIPLAYER_PLAN.md §4) ----------------------------------------
# Per player: whose doors and chests they share. Stored as owner id -> [ids],
# in friends.json next to server.json.

var friends: Dictionary = {}

func friends_path() -> String:
	return path.get_base_dir().path_join("friends.json")

func load_friends() -> void:
	var f: Variant = JSON.parse_string(FileAccess.get_file_as_string(friends_path())) \
		if FileAccess.file_exists(friends_path()) else null
	friends = f if f is Dictionary else {}

## `owner` lets `friend` use their things.
func add_friend(owner: String, friend: String) -> void:
	var l: Array = friends.get(owner, [])
	if not friend in l:
		l.append(friend)
	friends[owner] = l
	_write(friends_path(), friends)

func remove_friend(owner: String, friend: String) -> bool:
	var l: Array = friends.get(owner, [])
	if not friend in l:
		return false
	l.erase(friend)
	friends[owner] = l
	_write(friends_path(), friends)
	return true

func is_friend(owner: String, friend: String) -> bool:
	return friend in friends.get(owner, [])