extends Node
class_name Rules

## The game layer: what a shot is worth, when a ball ends, and when the game does.
##
## Table emits, Main forwards, this decides. It owns no geometry — the only things it calls
## back into the table with are reset_bank / set_rollover_lit / add_ball / park_ball, which
## are exactly the devices whose *state* a ruleset is supposed to own.
##
## The shape of the scoring: bumpers and slings are chatter, ramps and saucers are money,
## a whipped spinner is a jackpot and a dribbled one is a rounding error, and the combo
## multiplier is where a good player pulls away from a lucky one. Pops deliberately do NOT
## build combo — if they did, the top of the table would max the multiplier for free and
## aiming would stop mattering.
##
## Godot 4.7. No assets, no scene: pure state.

## Fired for anything worth putting on a display. Small hits stay silent (see AWARD_FLOOR)
## so a HUD isn't a waterfall of "+250 BUMPER"; poll score() for the running total.
signal awarded(text: String, points: int)

const BALLS_PER_GAME := 3

const COMBO_WINDOW := 2.5       ## seconds of grace before a chain goes cold
const COMBO_STEP := 0.5         ## each chained shot adds this to the multiplier
const COMBO_CAP := 8.0

const BALL_SAVE := 7.0          ## grace after launch — an early drain is a robbery otherwise
const DRAIN_DEBOUNCE := 400     ## msec; see on_drained()
const AWARD_FLOOR := 1000       ## below this an award is scored but not announced

const MB_MULT := 3.0
const LOCKS_FOR_MB := 3
const JACKPOT := 10000
const JACKPOT_STEP := 5000

const BANK_BONUS := 5000        ## × how many times that bank has been cleared
const BANK_ESCALATE_CAP := 6
const BANK_RESET_DELAY := 0.7   ## see _reset_bank_soon()

const LANE_BONUS := 3000        ## × current lane level, for completing the word
const LANE_LEVEL_CAP := 6

## Nudge heat: each shove adds 1.0 and it bleeds off at NUDGE_COOL/sec. Two warnings, then
## the tilt — a tilt with no warning is just the table stealing a ball off you.
const NUDGE_COOL := 0.75
const TILT_WARN_AT := [2.0, 3.0]
const TILT_AT := 4.0

const SCORES_PATH := "user://pinball_scores.cfg"

## End-of-ball bonus units per hit, paid out at drain × lane level. Deliberately flat and
## unmultiplied: the bonus rewards *playing the ball out*, the score rewards playing it well.
const BONUS_UNITS := {
	"bumper": 10, "sling": 10, "target": 50, "drop": 100,
	"spinner": 8, "saucer": 500, "rollover": 120, "ramp": 250,
}

## Which shots keep a chain alive. Aimed shots only.
const COMBO_KINDS := ["target", "drop", "bank_cleared", "spinner", "saucer", "rollover", "ramp"]

var tilted := false             ## Main reads this directly to kill the flippers

var _main: Node = null
var _table: Table = null

var _score := 0
var _ball := 1
var _game_over := false
var _high := 0
var _high_key := "table"

var _combo := 0
var _combo_left := 0.0

var _bonus := 0
var _lane_level := 1
var _lane_ids: PackedStringArray = []

var _save_left := 0.0
var _save_used := false

var _locks := 0
var _mb_active := false
var _jackpot := JACKPOT

var _bank_clears: Dictionary = {}   # bank name -> times cleared this game

var _nudge_heat := 0.0
var _warns_given := 0

## instance id -> msec of its last drain. Keyed by id rather than node because a drained
## multiball ball is freed while this is still holding it, and a timestamp rather than a
## coroutine because a cleanup that fails to run would wedge that ball out of the game.
var _draining: Dictionary = {}

# ---------------------------------------------------------------- lifecycle
func setup(main: Node) -> void:
	_main = main

func start_game(table: Table) -> void:
	_table = table
	_score = 0
	_ball = 1
	_game_over = false
	_combo = 0
	_combo_left = 0.0
	_bonus = 0
	_lane_level = 1
	_locks = 0
	_mb_active = false
	_jackpot = JACKPOT
	_bank_clears.clear()
	_save_left = 0.0
	_save_used = false
	_nudge_heat = 0.0
	_warns_given = 0
	_draining.clear()
	tilted = false

	_high_key = table.table_name().to_lower().replace(" ", "_")
	_high = _read_high(_high_key)
	_cache_lanes()
	for id in _lane_ids:
		table.set_rollover_lit(id, false)

	# Ball save has to arm on the PLUNGE, not on start_game, and Main doesn't forward
	# ball_launched to us — so listen to the table directly. Main rebuilds the same Table
	# node per layout, hence the is_connected guard rather than a fresh connect.
	if not table.ball_launched.is_connected(_on_ball_launched):
		table.ball_launched.connect(_on_ball_launched)

	print("[rules] game start — %s · %d balls · high %s" % [
		table.table_name(), BALLS_PER_GAME, commas(_high)])
	awarded.emit("BALL 1", 0)

func _process(delta: float) -> void:
	if _combo_left > 0.0:
		_combo_left = maxf(0.0, _combo_left - delta)
		if _combo_left == 0.0:
			_combo = 0
	if _save_left > 0.0:
		_save_left = maxf(0.0, _save_left - delta)
		if _save_left == 0.0 and not _save_used:
			awarded.emit("SAVE OVER", 0)
	if _nudge_heat > 0.0:
		_nudge_heat = maxf(0.0, _nudge_heat - delta * NUDGE_COOL)
		if _nudge_heat == 0.0:
			_warns_given = 0

func _on_ball_launched(_b: RigidBody3D) -> void:
	# Multiball adds balls through this same signal; those must not re-arm the save.
	if _game_over or _mb_active or _save_used or _save_left > 0.0:
		return
	_save_left = BALL_SAVE
	awarded.emit("BALL SAVE", 0)

# ---------------------------------------------------------------- scoring
func on_hit(kind: String, id: String, _at: Vector3, data: Dictionary) -> void:
	if _game_over or tilted or _table == null:
		return

	if kind == "bank_cleared":
		_bank_cleared(id)
		return

	var base := int(data.get("points", 0))
	var label := kind.to_upper()

	match kind:
		"spinner":
			# The whole point of a spinner: points PER SPIN, and spins come from speed.
			var spins := maxi(1, int(data.get("spins", 1)))
			base *= spins
			label = "SPINNER %d" % spins
		"rollover":
			label = "LANE %s" % String(data.get("glyph", "?"))

	_bonus += _bonus_for(kind, data)
	_award(base, label)
	# Combo grows AFTER the award, so the first shot of a chain pays 1x and the reward for
	# chaining shows up on the next one. Extending first would silently gift a lone shot 1.5x.
	_extend_combo(kind)

	# Device state runs after the award so a lane bonus lands on top of the lane's own value.
	match kind:
		"rollover": _lane_rolled(id)
		"saucer": _saucer_captured()
		"ramp":
			if _mb_active:
				_pay_jackpot("RAMP JACKPOT")

## Everything that adds to the score goes through here, so the multipliers can never be
## forgotten at a call site.
func _award(base: int, label: String, announce := false) -> int:
	if base <= 0:
		return 0
	var pts := int(round(float(base) * combo() * _mb_mult()))
	_score += pts
	if _score > _high:
		_high = _score     # live, so a HUD can show the record falling as it happens
	if announce or pts >= AWARD_FLOOR:
		awarded.emit(label, pts)
	return pts

func _extend_combo(kind: String) -> void:
	if not COMBO_KINDS.has(kind):
		return    # pops and slings ride the multiplier but never build it
	_combo = mini(_combo + 1, int((COMBO_CAP - 1.0) / COMBO_STEP))
	_combo_left = COMBO_WINDOW

func _bonus_for(kind: String, data: Dictionary) -> int:
	var unit := int(BONUS_UNITS.get(kind, 25))
	if kind == "spinner":
		unit *= maxi(1, int(data.get("spins", 1)))
	return unit

func _mb_mult() -> float:
	return MB_MULT if _mb_active else 1.0

# ---------------------------------------------------------------- devices
## A whole drop bank down. Escalates every time you knock it over again in the same game,
## which is what turns a bank from a chore into a strategy.
func _bank_cleared(bank: String) -> void:
	var n := int(_bank_clears.get(bank, 0)) + 1
	_bank_clears[bank] = n
	var step := mini(n, BANK_ESCALATE_CAP)
	_bonus += 1000 * step
	_award(BANK_BONUS * step, "%s BANK x%d" % [bank.to_upper(), step], true)
	_extend_combo("bank_cleared")
	_reset_bank_soon(bank)

## Reset on a beat, not instantly: the ball is still sitting inside the last target's
## trigger volume when this fires, and popping the bank up underneath it re-clears the
## whole thing for free — an infinite bonus loop from one lucky shot.
func _reset_bank_soon(bank: String) -> void:
	var t := _table
	var tree := get_tree()
	if tree == null:
		t.reset_bank(bank)      # no tree, no timers, and nothing to race either
		return
	await tree.create_timer(BANK_RESET_DELAY).timeout
	if is_instance_valid(t):
		t.reset_bank(bank)      # no-op if the table was swapped out from under us

func _cache_lanes() -> void:
	_lane_ids = PackedStringArray()
	if _table == null:
		return
	for n in _table.parts_of("rollover"):
		_lane_ids.append(String((n as Node).get_meta("id", "")))

func _lane_rolled(id: String) -> void:
	var n := _table.part(id)
	if n == null or _lane_ids.is_empty():
		return    # an uncached lane set would read as "all lit" and pay out forever
	if not bool(n.get_meta("lit", false)):
		_table.set_rollover_lit(id, true)
	for lid in _lane_ids:
		var l := _table.part(lid)
		if l == null or not bool(l.get_meta("lit", false)):
			return
	# every lane lit: pay the word, advance the bonus multiplier, wipe them for the next lap
	_award(LANE_BONUS * _lane_level, "%s COMPLETE" % _lane_word(), true)
	_lane_level = mini(_lane_level + 1, LANE_LEVEL_CAP)
	for lid in _lane_ids:
		_table.set_rollover_lit(lid, false)
	awarded.emit("BONUS x%d" % _lane_level, 0)

func _lane_word() -> String:
	var s := ""
	for lid in _lane_ids:
		var n := _table.part(lid)
		if n != null:
			s += String(n.get_meta("glyph", ""))
	return s if s != "" else "LANES"

## Saucers are the lock device on every table in Tables.gd, so any capture counts.
func _saucer_captured() -> void:
	if _mb_active:
		_pay_jackpot("SAUCER JACKPOT")
		return
	_locks += 1
	if _locks < LOCKS_FOR_MB:
		awarded.emit("LOCK %d/%d" % [_locks, LOCKS_FOR_MB], 0)
		return
	_start_multiball()

func _start_multiball() -> void:
	_locks = 0
	_jackpot = JACKPOT
	_mb_active = true       # set BEFORE add_ball: it emits ball_launched, which must not re-arm the save
	awarded.emit("MULTIBALL", 0)
	for i in 2:
		var b := _table.add_ball()
		# add_ball only nudges the new ball at ~0.4 m/s and it spawns in the plunger lane,
		# where the tilted gravity vector will just roll it back down. Give it a real plunge.
		if is_instance_valid(b):
			b.apply_central_impulse(Vector3(0, 0, -0.30))

func _pay_jackpot(label: String) -> void:
	_award(_jackpot, label, true)
	_jackpot += JACKPOT_STEP

# ---------------------------------------------------------------- drain / ball count
func on_drained(ball: RigidBody3D) -> void:
	if _table == null or not is_instance_valid(ball):
		return
	# The drain Area fires on entry and park_ball's teleport takes a frame to register, so
	# the same ball can arrive here twice before it has actually gone anywhere.
	var iid := ball.get_instance_id()
	var now := Time.get_ticks_msec()
	if now - int(_draining.get(iid, -DRAIN_DEBOUNCE)) < DRAIN_DEBOUNCE:
		return
	_draining[iid] = now

	if _game_over:
		_table.park_ball(ball)
		return

	# Multiball: any ball but the last just leaves the game quietly.
	if _table.balls.size() > 1:
		_table.remove_ball(ball)
		if _mb_active and _table.balls.size() <= 1:
			_mb_active = false
			awarded.emit("MULTIBALL OVER", 0)
		return

	if _mb_active:
		_mb_active = false      # defensive: balls vanished some other way

	# Ball save. A tilt forfeits it — that is the price of shoving the table.
	if _save_left > 0.0 and not _save_used and not tilted:
		_save_used = true
		_save_left = 0.0
		_combo = 0
		_combo_left = 0.0
		_table.park_ball(ball)
		awarded.emit("BALL SAVED", 0)
		return

	_end_ball(ball)

func _end_ball(ball: RigidBody3D) -> void:
	var payout := _bonus * _lane_level
	if payout > 0:
		_score += payout
		if _score > _high:
			_high = _score
		awarded.emit("BONUS x%d" % _lane_level, payout)

	_ball += 1
	_combo = 0
	_combo_left = 0.0
	_bonus = 0
	_save_left = 0.0
	_save_used = false
	_nudge_heat = 0.0
	_warns_given = 0
	tilted = false          # the tilt dies with the ball, not with the game

	if _ball > BALLS_PER_GAME:
		_game_over = true
		_table.park_ball(ball)
		_finish()
		return

	_table.park_ball(ball)
	awarded.emit("BALL %d" % _ball, 0)

func _finish() -> void:
	var record := _score >= _read_high(_high_key) and _score > 0
	_write_high(_high_key, _score)
	awarded.emit("GAME OVER", _score)
	if record:
		awarded.emit("HIGH SCORE", _score)
	print("[rules] game over — %s: %s%s" % [
		_table.table_name(), commas(_score), "  (NEW HIGH)" if record else ""])

# ---------------------------------------------------------------- tilt
func on_nudge() -> void:
	if _game_over or tilted:
		return
	_nudge_heat += 1.0
	if _nudge_heat >= TILT_AT:
		_tilt()
		return
	while _warns_given < TILT_WARN_AT.size() and _nudge_heat >= float(TILT_WARN_AT[_warns_given]):
		_warns_given += 1
		awarded.emit("DANGER" if _warns_given > 1 else "WARNING", 0)

func _tilt() -> void:
	tilted = true
	_bonus = 0          # the bonus is what a tilt actually costs you
	_combo = 0
	_combo_left = 0.0
	_nudge_heat = 0.0
	awarded.emit("TILT", 0)

# ---------------------------------------------------------------- high scores
func _read_high(key: String) -> int:
	var cf := ConfigFile.new()
	if cf.load(SCORES_PATH) != OK:
		return 0
	return int(cf.get_value("high", key, 0))

func _write_high(key: String, value: int) -> void:
	var cf := ConfigFile.new()
	cf.load(SCORES_PATH)        # ignore the error: a missing file is just an empty one
	if value > int(cf.get_value("high", key, 0)):
		cf.set_value("high", key, value)
		cf.save(SCORES_PATH)

# ---------------------------------------------------------------- getters (the HUD lane's API)
func score() -> int:
	return _score

func ball() -> int:
	return mini(_ball, BALLS_PER_GAME)

func balls_total() -> int:
	return BALLS_PER_GAME

## How many tilt warnings are showing. TILT_WARN_AT.size() is the max before the tilt lands,
## and the Hud lane reads that constant to render "n/max" — keep them in step.
func warnings() -> int:
	return _warns_given

## The live scoring multiplier, e.g. 2.5 — not the chain length. combo_count() is that.
func combo() -> float:
	return minf(1.0 + COMBO_STEP * float(_combo), COMBO_CAP)

func combo_count() -> int:
	return _combo

func combo_left() -> float:
	return _combo_left

func high_score() -> int:
	return _high

func bonus() -> int:
	return _bonus

func lane_level() -> int:
	return _lane_level

func locks() -> int:
	return _locks

func multiball() -> bool:
	return _mb_active

func multiplier() -> float:
	return combo() * _mb_mult()

func ball_save_left() -> float:
	return _save_left

func game_over() -> bool:
	return _game_over

func balls_in_play() -> int:
	return _table.balls.size() if _table != null else 0

func score_text() -> String:
	return commas(_score)

## Which layout the score belongs to — high scores are kept per table, so a HUD showing
## the record needs this to label it. Empty if Rules was spawned without a Main.
func table_id() -> String:
	if _main == null:
		return ""
	var v: Variant = _main.get("table_id")
	return String(v) if v != null else ""

func status_line() -> String:
	if _game_over:
		return "GAME OVER  ·  HIGH %s  ·  R FOR A NEW GAME" % commas(_high)
	if tilted:
		return "TILT  ·  FLIPPERS DEAD UNTIL THE DRAIN"
	var bits := PackedStringArray()
	bits.append("BALL %d/%d" % [ball(), BALLS_PER_GAME])
	if _mb_active:
		bits.append("MULTIBALL x%d" % int(MB_MULT))
	elif _locks > 0:
		bits.append("LOCK %d/%d" % [_locks, LOCKS_FOR_MB])
	if _combo > 0:
		bits.append("COMBO x%s" % _mult_text(combo()))
	if _save_left > 0.0:
		bits.append("SAVE %d" % int(ceil(_save_left)))
	if _lane_level > 1:
		bits.append("BONUS x%d" % _lane_level)
	if _warns_given > 0:
		bits.append("NUDGE %d/2" % mini(_warns_given, 2))
	return "  ·  ".join(bits)

func _mult_text(m: float) -> String:
	return "%d" % int(m) if is_equal_approx(m, floor(m)) else "%.1f" % m

## Score displays need thousands separators or a six-figure number reads as noise.
static func commas(n: int) -> String:
	var s := str(absi(n))
	var out := ""
	for i in s.length():
		if i > 0 and (s.length() - i) % 3 == 0:
			out += ","
		out += s[i]
	return ("-" + out) if n < 0 else out