extends Node3D
## A cast fishing float.
##
## flying -> it arcs out from the rod tip.
## floating -> it landed on deep enough water; a fish bites after a while
##   (sooner at dawn and dusk, and in the rain).
## biting -> the float dips; you have BITE_WINDOW seconds to reel in
##   (Actions.reel), or the fish gets away and you wait again.
## landed -> it fell on dry ground: nothing will bite. Reel in and try again.
## Walking too far away snaps the line.
##
## A line is drawn from the rod tip each frame (hands.gd gives the tip).

const BITE_WINDOW := 1.5
const MIN_DEPTH := 0.5            ## water this deep under the float, or no fish
const LINE_LENGTH := 26.0

var world: Node3D
var player: Node3D
var state := "flying"
var velocity := Vector3.ZERO
var fish := ""                    ## what's on the line while biting
var wait_left := 0.0
var bite_left := 0.0
var rng := RandomNumberGenerator.new()
var tip := Vector3.ZERO           ## rod tip, world space (set by hands.gd)
var _t := 0.0
var _mesh: MeshInstance3D
var _line: MeshInstance3D
var _imesh: ImmediateMesh

func setup(w: Node3D, p: Node3D, from: Vector3, vel: Vector3, seed: int) -> void:
	world = w
	player = p
	velocity = vel
	position = from
	tip = from
	rng.seed = seed
	_mesh = MeshInstance3D.new()
	_mesh.mesh = ItemDB.mesh_for("bobber")
	_mesh.material_override = ItemDB.item_material()
	_mesh.cast_shadow = GeometryInstance3D.SHADOW_CASTING_SETTING_OFF
	add_child(_mesh)
	_imesh = ImmediateMesh.new()
	_line = MeshInstance3D.new()
	_line.mesh = _imesh
	_line.top_level = true
	_line.cast_shadow = GeometryInstance3D.SHADOW_CASTING_SETTING_OFF
	var lm := StandardMaterial3D.new()
	lm.shading_mode = BaseMaterial3D.SHADING_MODE_UNSHADED
	lm.albedo_color = Color(0.9, 0.9, 0.85, 0.7)
	lm.transparency = BaseMaterial3D.TRANSPARENCY_ALPHA
	_line.material_override = lm
	add_child(_line)

func _physics_process(delta: float) -> void:
	step(delta)

func _process(_delta: float) -> void:
	_draw_line()

## How long until the next bite (seconds).
func _next_wait() -> float:
	var h: float = world.day_night.hours()
	var k := 1.0
	if (h > 5.0 and h < 8.5) or (h > 17.0 and h < 20.5):
		k *= 0.6                      # fish feed at dawn and dusk
	if world.weather.precip > 0.3:
		k *= 0.8
	return rng.randf_range(5.0, 14.0) * k

func _pick_fish() -> String:
	var h: float = world.day_night.hours()
	var trout := 0.4 if (h > 5.0 and h < 8.5) or (h > 17.0 and h < 20.5) else 0.22
	return "trout" if rng.randf() < trout else "perch"

func step(dt: float) -> void:
	_t += dt
	var terrain: Node3D = world.terrain
	if global_position.distance_to(player.global_position) > LINE_LENGTH + 4.0:
		Actions.notify.emit("The line snapped")
		world.end_fishing()
		return
	match state:
		"flying":
			velocity.y -= 9.8 * dt
			var p := global_position + velocity * dt
			var ground: float = terrain.sample_height(p.x, p.z)
			if p.y <= terrain.water_level and ground < terrain.water_level - MIN_DEPTH:
				p.y = terrain.water_level
				state = "floating"
				wait_left = _next_wait()
			elif p.y <= ground + 0.03:
				p.y = ground + 0.03
				state = "landed"
				Actions.notify.emit("Cast into the water (deeper than this)" if ground < terrain.water_level else "Cast into the water")
			global_position = p
		"floating":
			wait_left -= dt
			_mesh.position.y = sin(_t * 2.2) * 0.012
			if wait_left <= 0.0:
				state = "biting"
				fish = _pick_fish()
				bite_left = BITE_WINDOW
				Actions.notify.emit("Bite! Click to reel in")
		"biting":
			bite_left -= dt
			# The float bobs hard and goes under.
			_mesh.position.y = -0.06 + sin(_t * 18.0) * 0.03
			if bite_left <= 0.0:
				state = "floating"
				fish = ""
				wait_left = _next_wait() * 1.3
				_mesh.position.y = 0.0
				Actions.notify.emit("It got away")

func _draw_line() -> void:
	_imesh.clear_surfaces()
	_imesh.surface_begin(Mesh.PRIMITIVE_LINE_STRIP)
	var a := tip
	var b := global_position + Vector3(0, 0.1, 0)
	for i in range(13):
		var k := i / 12.0
		var p := a.lerp(b, k)
		p.y -= sin(k * PI) * 0.06 * a.distance_to(b) * (0.3 if state == "biting" else 1.0)   # slack
		_imesh.surface_add_vertex(p)
	_imesh.surface_end()