extends Node3D

const CHARACTER_API_URL := "https://pchar.ranaze.com/api/Characters"

@export var tile_size := 16.0
@export var block_height := 1.0
@export_range(1, 8, 1) var tile_radius := 3
@export var tracked_node_path: NodePath
@export var player_spawn_height := 2.0
@export var border_color: Color = Color(0.05, 0.05, 0.05, 1.0)
@export var border_height_bias := 0.005
@export var show_tile_labels := true
@export var tile_label_height := 0.01
@export var tile_label_color: Color = Color(1, 1, 1, 1)

@onready var _block: MeshInstance3D = $TerrainBlock
@onready var _player: RigidBody3D = $Player
@onready var _camera: Camera3D = $Player/Camera3D

var _center_coord := Vector2i.ZERO
var _tiles_root: Node3D
var _tracked_node: Node3D
var _tile_nodes: Dictionary = {}
var _camera_start_offset := Vector3(0.0, 6.0, 10.0)
var _border_material: StandardMaterial3D
var _known_locations: Dictionary = {}
var _locations_loaded := false
var _character_id := ""
var _persisted_coord := Vector2i.ZERO
var _coord_sync_in_flight := false
var _queued_coord_sync: Variant = null
var _locations_refresh_in_flight := false
var _queued_locations_refresh := false


func _ready() -> void:
	_tiles_root = Node3D.new()
	_tiles_root.name = "GeneratedTiles"
	add_child(_tiles_root)

	if _camera:
		_camera_start_offset = _camera.position

	_tracked_node = get_node_or_null(tracked_node_path) as Node3D
	if _tracked_node == null:
		_tracked_node = _player

	var start_coord := SelectedCharacter.get_coord()
	_center_coord = Vector2i(roundi(start_coord.x), roundi(start_coord.y))
	_persisted_coord = _center_coord
	_character_id = String(SelectedCharacter.character.get("id", SelectedCharacter.character.get("Id", ""))).strip_edges()

	_block.visible = false
	await _load_existing_locations()
	_ensure_selected_location_exists(_center_coord)
	_rebuild_tiles(_center_coord)
	_move_player_to_coord(_center_coord)


func _process(_delta: float) -> void:
	if not _locations_loaded:
		return
	var target_world_pos := _get_stream_position()
	var target_coord := _world_to_coord(target_world_pos)
	if target_coord == _center_coord:
		return
	_center_coord = target_coord
	_queue_coord_sync(_center_coord)
	_queue_locations_refresh()


func _get_stream_position() -> Vector3:
	if _tracked_node:
		return _tracked_node.global_position
	return _coord_to_world(_center_coord)


func _world_to_coord(world_pos: Vector3) -> Vector2i:
	return Vector2i(
		roundi(world_pos.x / tile_size),
		roundi(world_pos.z / tile_size)
	)


func _coord_to_world(coord: Vector2i) -> Vector3:
	return Vector3(coord.x * tile_size, block_height * 0.5, coord.y * tile_size)


func _move_player_to_coord(coord: Vector2i) -> void:
	if _player == null:
		return
	_player.global_position = Vector3(coord.x * tile_size, player_spawn_height, coord.y * tile_size)
	_player.linear_velocity = Vector3.ZERO
	_player.angular_velocity = Vector3.ZERO


func _rebuild_tiles(center: Vector2i) -> void:
	var wanted_keys: Dictionary = {}
	for x in range(center.x - tile_radius, center.x + tile_radius + 1):
		for y in range(center.y - tile_radius, center.y + tile_radius + 1):
			var coord := Vector2i(x, y)
			if not _known_locations.has(coord):
				continue
			wanted_keys[coord] = true
			if _tile_nodes.has(coord):
				continue
			_spawn_tile(coord, String(_known_locations[coord]))

	for key in _tile_nodes.keys():
		if wanted_keys.has(key):
			continue
		var tile_node := _tile_nodes[key] as Node3D
		if tile_node:
			tile_node.queue_free()
		_tile_nodes.erase(key)


func _spawn_tile(coord: Vector2i, location_name: String) -> void:
	var tile_root := Node3D.new()
	tile_root.name = "Tile_%d_%d" % [coord.x, coord.y]
	tile_root.position = _coord_to_world(coord)
	_tiles_root.add_child(tile_root)

	var tile_body := StaticBody3D.new()
	tile_body.name = "TileBody"
	tile_body.scale = Vector3(tile_size, block_height, tile_size)
	tile_root.add_child(tile_body)

	var collision_shape := CollisionShape3D.new()
	collision_shape.name = "CollisionShape3D"
	collision_shape.shape = BoxShape3D.new()
	tile_body.add_child(collision_shape)

	var tile := _block.duplicate() as MeshInstance3D
	tile.name = "TileMesh"
	tile.visible = true
	tile_body.add_child(tile)

	tile.add_child(_create_tile_border())
	if show_tile_labels:
		tile_root.add_child(_create_tile_label(location_name))

	_tile_nodes[coord] = tile_root


func _create_tile_border() -> MeshInstance3D:
	var top_y := 0.5 + border_height_bias
	var corners := [
		Vector3(-0.5, top_y, -0.5),
		Vector3(0.5, top_y, -0.5),
		Vector3(0.5, top_y, 0.5),
		Vector3(-0.5, top_y, 0.5),
	]

	var border_mesh := ImmediateMesh.new()
	border_mesh.surface_begin(Mesh.PRIMITIVE_LINES, _get_border_material())
	for idx in range(corners.size()):
		var current: Vector3 = corners[idx]
		var next: Vector3 = corners[(idx + 1) % corners.size()]
		border_mesh.surface_add_vertex(current)
		border_mesh.surface_add_vertex(next)
	border_mesh.surface_end()

	var border := MeshInstance3D.new()
	border.name = "TileBorder"
	border.mesh = border_mesh
	return border


func _get_border_material() -> StandardMaterial3D:
	if _border_material:
		return _border_material

	_border_material = StandardMaterial3D.new()
	_border_material.albedo_color = border_color
	_border_material.shading_mode = BaseMaterial3D.SHADING_MODE_UNSHADED
	_border_material.disable_receive_shadows = true
	_border_material.no_depth_test = true
	return _border_material


func _create_tile_label(location_name: String) -> Label3D:
	var label := Label3D.new()
	label.name = "LocationNameLabel"
	label.text = location_name
	label.position = Vector3(0.0, (block_height * 0.5) + border_height_bias + tile_label_height, 0.0)
	label.rotation_degrees = Vector3(-90.0, 0.0, 0.0)
	label.billboard = BaseMaterial3D.BILLBOARD_DISABLED
	label.modulate = tile_label_color
	label.pixel_size = 0.01
	label.outline_size = 12
	label.no_depth_test = false
	return label


func _ensure_selected_location_exists(coord: Vector2i) -> void:
	if _known_locations.has(coord):
		return
	_known_locations[coord] = _selected_location_name(coord)


func _selected_location_name(coord: Vector2i) -> String:
	var selected_name := String(SelectedCharacter.character.get("locationName", "")).strip_edges()
	if not selected_name.is_empty():
		return selected_name
	var character_name := String(SelectedCharacter.character.get("name", "")).strip_edges()
	if not character_name.is_empty():
		return "%s's Location" % character_name
	return "Location %d,%d" % [coord.x, coord.y]


func _load_existing_locations() -> void:
	_locations_refresh_in_flight = true
	_locations_loaded = false
	_known_locations.clear()

	if _character_id.is_empty():
		push_warning("Selected character is missing an id; cannot load visible locations.")
		_locations_loaded = true
		return

	var request := HTTPRequest.new()
	add_child(request)

	var headers := PackedStringArray()
	if not AuthState.access_token.is_empty():
		headers.append("Authorization: Bearer %s" % AuthState.access_token)

	var err := request.request("%s/%s/visible-locations" % [CHARACTER_API_URL, _character_id], headers, HTTPClient.METHOD_GET)
	if err != OK:
		push_warning("Failed to request visible locations: %s" % err)
		request.queue_free()
		_locations_loaded = true
		return

	var result: Array = await request.request_completed
	request.queue_free()

	var result_code: int = result[0]
	var response_code: int = result[1]
	var response_body: String = result[3].get_string_from_utf8()
	if result_code != HTTPRequest.RESULT_SUCCESS or response_code < 200 or response_code >= 300:
		push_warning("Failed to load visible locations (%s/%s): %s" % [result_code, response_code, response_body])
		_locations_loaded = true
		return

	var parsed: Variant = JSON.parse_string(response_body)
	if typeof(parsed) != TYPE_ARRAY:
		push_warning("Visible locations response was not an array.")
		_locations_loaded = true
		return

	var loaded_count := 0
	for item in parsed:
		if typeof(item) != TYPE_DICTIONARY:
			continue
		var location := item as Dictionary
		var coord_variant: Variant = location.get("coord", {})
		if typeof(coord_variant) != TYPE_DICTIONARY:
			continue
		var coord_dict := coord_variant as Dictionary
		var coord := Vector2i(int(coord_dict.get("x", 0)), int(coord_dict.get("y", 0)))
		var location_name := String(location.get("name", "")).strip_edges()
		if location_name.is_empty():
			location_name = "Location %d,%d" % [coord.x, coord.y]
		_known_locations[coord] = location_name
		loaded_count += 1

	print("LocationLevel loaded %d visible locations for character %s." % [loaded_count, _character_id])
	if loaded_count == 0:
		push_warning("Visible locations request succeeded but returned 0 locations for character %s." % _character_id)

	_locations_loaded = true
	_locations_refresh_in_flight = false
	_rebuild_tiles(_center_coord)
	if _queued_locations_refresh:
		_queued_locations_refresh = false
		_queue_locations_refresh()


func _queue_locations_refresh() -> void:
	if _locations_refresh_in_flight:
		_queued_locations_refresh = true
		return
	_refresh_visible_locations()


func _refresh_visible_locations() -> void:
	if _character_id.is_empty():
		return
	_refresh_visible_locations_async()


func _refresh_visible_locations_async() -> void:
	await _load_existing_locations()


func _queue_coord_sync(coord: Vector2i) -> void:
	if coord == _persisted_coord:
		return
	if _coord_sync_in_flight:
		_queued_coord_sync = coord
		return
	_sync_character_coord(coord)


func _sync_character_coord(coord: Vector2i) -> void:
	if _character_id.is_empty():
		return
	_coord_sync_in_flight = true
	_queued_coord_sync = null
	_sync_character_coord_async(coord)


func _sync_character_coord_async(coord: Vector2i) -> void:
	var response := await CharacterService.update_character_coord(_character_id, coord)
	if response.get("ok", false):
		_persisted_coord = coord
		SelectedCharacter.set_coord(coord)
	else:
		push_warning("Failed to persist character coord to %s,%s: status=%s error=%s body=%s" % [
			coord.x,
			coord.y,
			response.get("status", "n/a"),
			response.get("error", ""),
			response.get("body", "")
		])

	_coord_sync_in_flight = false
	if _queued_coord_sync != null and _queued_coord_sync is Vector2i and _queued_coord_sync != _persisted_coord:
		var queued_coord: Vector2i = _queued_coord_sync
		_sync_character_coord(queued_coord)