class_name Water extends Node2D

signal water_reached_max_height
@onready var player : Player = %Player
@export var animation_height : float = 0
@export var radius_base : float = 0
var tsunami_speed : float = 1

var radius : float:
	set(new_radius):
		radius = new_radius
		var mesh = get_node_or_null("WaterMesh")
		if !is_instance_valid(mesh):
			return
		update_scale(mesh)
		mesh.material.set_shader_parameter("radius", radius)
		
@export var amplitude : float:
	set(new_amplitude):
		amplitude = new_amplitude
		var mesh = get_node_or_null("WaterMesh")
		if !is_instance_valid(mesh):
			return
		update_scale(mesh)
		mesh.material.set_shader_parameter("amplitude", amplitude)

@export var tsunami_size : float:
	set(new_size):
		tsunami_size = new_size
		var mesh = get_node_or_null("WaterMesh")
		if !is_instance_valid(mesh):
			return
		update_scale(mesh)
		mesh.material.set_shader_parameter("tsunami_size", tsunami_size)

var tsunami_angle : float:
	set(new_angle):
		tsunami_angle = new_angle
		var mesh = get_node_or_null("WaterMesh")
		if !is_instance_valid(mesh):
			return
		update_scale(mesh)
		mesh.material.set_shader_parameter("tsunami_angle", tsunami_angle)

func check_player_collision():
	var pos = player.position
	var angle = atan2(pos.y, pos.x)
	var water_height = get_height_at(angle)
	var player_height = sqrt(pos.x * pos.x + pos.y * pos.y)
	if(water_height > player_height - 25):
		if player.hurt(1, Vector2.ZERO):
			player.reset_to_velocity = Vector2(0, -2000)
	
	

func get_height_at(angle):
	var TIME : float = Time.get_ticks_usec() / 1000000.;
	var wave1 = amplitude/1. * sin(150. * angle + TIME);
	var wave2 = amplitude/2. * sin(90. * angle + 1.6 * TIME);
	var wave3 = amplitude/3. * sin(55. * angle + 2.3 * TIME);
	var wave4 = amplitude/4. * sin(35. * angle + 3.9 * TIME);
	var wave = wave1 + wave2 + wave3 + wave4;
	
	var angle_diff : float = angle - tsunami_angle;
	angle_diff = fmod(angle_diff + PI + TAU, TAU) - PI;
	var sinc : float = (sin(20. * angle_diff) / angle_diff/ 20.);
	var tsunami : float = pow(abs(sinc), 1.5) * tsunami_size * sign(sinc);
	return radius + wave + tsunami;
	
		
@export var animation_angle : float = 0
@export var tsunami_base_angle : float
		
@export var rise_from : float = 2500;
@export var rise_to : float = 3500;
@export var rise_time : float = 120; # in seconds
var auto_rise : bool = true;

@onready var start_unix_time : float = Time.get_unix_time_from_system()
var direction = 1;

func update_scale(mesh):
	mesh.scale = 2 * (radius + amplitude * 2.1 + tsunami_size) * Vector2.ONE

func update_shader():
	radius = radius
	amplitude = amplitude
	tsunami_angle = tsunami_angle
	tsunami_size = tsunami_size

func _ready() -> void:
	update_shader()
	radius_base = rise_from
	
	
	
	
func _process(_delta: float) -> void:
	check_player_collision()
	if auto_rise:
		var time: float = Time.get_unix_time_from_system()
		if time - start_unix_time > rise_time:
			auto_rise = false
			radius_base = rise_to
			water_reached_max_height.emit()
		else:
			radius_base = lerpf(rise_from, rise_to, (time - start_unix_time) / rise_time)
	
	tsunami_angle = tsunami_base_angle + animation_angle * direction * tsunami_speed;
	radius = radius_base + animation_height

	# direction is -1 for left, +1 for right
func create_tsunami(angle : float, dir : int, speed : float):
	tsunami_speed = speed
	if direction not in [-1, 1]:
		push_error("direction must be in {-1, 1}")
		return
	direction = dir
	tsunami_base_angle = angle;
		
	$Tsunami.play("tsunami")

func rise_water():
	await get_tree().create_timer(.03).timeout
	auto_rise = false
	$ParticleContainer.scale = Vector2.ONE * radius/3000
	var pos = player.position
	var angle = atan2(pos.y, pos.x)
	$ParticleContainer.rotation = angle + PI/2
	$ParticleContainer.position += Vector2.ONE
	$WaterRise.play("water_rise")
	await $WaterRise.animation_finished
	radius_base = radius_base + animation_height
	animation_height = 0