extends SceneTree

const SonarMaterial = preload("res://game/domain/sonar/sonar_material.gd")
const SiteTerrainData = preload("res://game/domain/sites/site_terrain_data.gd")
const TerrainHeightField = preload("res://game/domain/sites/terrain_height_field.gd")
const SitePlacement = preload("res://game/domain/sites/site_placement.gd")
const SiteRoute = preload("res://game/domain/sites/site_route.gd")
const DiveSiteDefinition = preload("res://game/domain/sites/dive_site_definition.gd")

const TEST_COUNT := 38

var _failures: Array[String] = []


func _init() -> void:
	_test_terrain_data_validation()
	_test_height_field_sampling()
	_test_site_definition_validation()

	if _failures.is_empty():
		print("Site domain unit tests: %d passed, 0 failed." % TEST_COUNT)
		quit(0)
	else:
		for failure: String in _failures:
			push_error(failure)
		print("Site domain unit tests: %d failed." % _failures.size())
		quit(1)


func _make_terrain(columns: int, rows: int) -> SiteTerrainData:
	var data := SiteTerrainData.new()
	data.columns = columns
	data.rows = rows
	data.cell_size_m = 2.0
	data.origin_x_m = -10.0
	data.origin_z_m = 100.0
	# Packed arrays are passed by value in GDScript: build locally, then assign.
	var elevations := PackedFloat32Array()
	var materials := PackedByteArray()
	elevations.resize(columns * rows)
	materials.resize(columns * rows)
	for row in rows:
		for column in columns:
			var index := row * columns + column
			# Plane sloping down toward +Z (south): -20 at row 0, -2 m per row.
			elevations[index] = -20.0 - 2.0 * float(row)
			materials[index] = (
				SonarMaterial.Value.ROCK if column == 0 else SonarMaterial.Value.SAND
			)
	data.elevations_m = elevations
	data.materials = materials
	return data


func _test_terrain_data_validation() -> void:
	var data := _make_terrain(3, 4)
	_expect(data.validation_error().is_empty(), "regular terrain data is valid")
	_expect(data.index_of(2, 3) == 11, "index is row-major with columns along X")

	var tiny := _make_terrain(1, 4)
	_expect(not tiny.validation_error().is_empty(), "terrain needs at least two columns")

	var mismatched := _make_terrain(3, 4)
	mismatched.elevations_m.resize(5)
	_expect(not mismatched.validation_error().is_empty(), "elevation array must match the grid")

	var non_finite := _make_terrain(3, 4)
	non_finite.elevations_m[0] = INF
	_expect(not non_finite.validation_error().is_empty(), "elevations must be finite")

	var metal_terrain := _make_terrain(3, 4)
	metal_terrain.materials[1] = SonarMaterial.Value.METAL
	_expect(not metal_terrain.validation_error().is_empty(), "terrain cells are rock or sand only")

	var bad_cell := _make_terrain(3, 4)
	bad_cell.cell_size_m = 0.0
	_expect(not bad_cell.validation_error().is_empty(), "cell size must be positive")

	var bad_reflectivity := _make_terrain(3, 4)
	bad_reflectivity.sand_reflectivity = 1.5
	_expect(not bad_reflectivity.validation_error().is_empty(), "reflectivity stays within 0..1")
	_expect(TerrainHeightField.from_data(bad_reflectivity) == null, "invalid data yields no field")


func _test_height_field_sampling() -> void:
	var field := TerrainHeightField.from_data(_make_terrain(3, 4))
	_expect(field != null, "valid data yields a field")
	if field == null:
		return
	_expect(field.bounds_m().is_equal_approx(Rect2(-10.0, 100.0, 4.0, 6.0)), "bounds cover (columns-1) by (rows-1) cells")
	_expect(field.cell_world_position(2, 3).is_equal_approx(Vector3(-6.0, -26.0, 106.0)), "cell position follows origin and cell size")
	_expect(is_equal_approx(field.elevation_at(-10.0, 100.0), -20.0), "elevation at a vertex is exact")
	_expect(is_equal_approx(field.elevation_at(-9.0, 101.0), -21.0), "elevation is bilinear between vertices")
	_expect(is_equal_approx(field.elevation_at(-50.0, 1000.0), -26.0), "sampling outside clamps to the nearest edge")
	_expect(field.material_at(-10.4, 100.0) == SonarMaterial.Value.ROCK, "material is the nearest cell")
	_expect(field.material_at(-6.0, 103.0) == SonarMaterial.Value.SAND, "material of an interior cell")
	_expect(field.normal_at_cell(1, 1).is_equal_approx(Vector3(0.0, 1.0, 1.0).normalized()), "normal leans against the downhill direction")
	_expect(not field.contains(-11.0, 100.0) and field.contains(-8.0, 103.0), "contains follows the bounds")
	_expect(is_equal_approx(field.reflectivity_for(SonarMaterial.Value.SAND), 0.45), "sand reflectivity comes from the data")


func _make_placement(id: String, kind: int, position: Vector3) -> SitePlacement:
	var placement := SitePlacement.new()
	placement.placement_id = StringName(id)
	placement.kind = kind
	placement.position_m = position
	placement.footprint_m = Vector3(4.0, 2.0, 3.0)
	return placement


func _make_route(id: String, waypoints: PackedVector3Array, maximum_depth: float) -> SiteRoute:
	var route := SiteRoute.new()
	route.route_id = StringName(id)
	route.waypoints_m = waypoints
	route.maximum_depth_m = maximum_depth
	return route


func _make_definition() -> DiveSiteDefinition:
	var definition := DiveSiteDefinition.new()
	definition.site_id = &"test_site"
	definition.display_name = "Site de test"
	definition.terrain = _make_terrain(3, 4)
	definition.playable_bounds_m = Rect2(-10.0, 100.0, 4.0, 6.0)
	definition.spawn_position_m = Vector3(-8.0, -10.0, 102.0)
	definition.spawn_yaw_radians = PI * 0.5
	var placements_list: Array[SitePlacement] = [
		_make_placement("target", SitePlacement.Kind.WRECK_TARGET, Vector3(-8.0, -23.0, 103.0)),
		_make_placement("anchor", SitePlacement.Kind.VESSEL_ANCHOR, Vector3(-8.0, -20.0, 100.5)),
	]
	definition.placements = placements_list
	var routes_list: Array[SiteRoute] = [
		_make_route(
			"safe",
			PackedVector3Array([Vector3(-8.0, -12.0, 101.0), Vector3(-8.0, -14.0, 103.0)]),
			20.0
		),
	]
	definition.routes = routes_list
	return definition


func _test_site_definition_validation() -> void:
	var definition := _make_definition()
	_expect(definition.validation_error().is_empty(), "complete definition is valid")
	_expect(definition.height_field() != null, "definition exposes its height field")
	_expect(definition.placement(&"target").kind == SitePlacement.Kind.WRECK_TARGET, "placement lookup by id")
	_expect(definition.placement(&"missing") == null, "unknown placement is null")
	_expect(definition.placements_of_kind(SitePlacement.Kind.VESSEL_ANCHOR).size() == 1, "placements filter by kind")
	_expect(definition.route(&"safe").waypoints_m.size() == 2, "route lookup by id")
	_expect(definition.spawn_transform().origin.is_equal_approx(Vector3(-8.0, -10.0, 102.0)), "spawn transform origin")
	_expect(
		(definition.spawn_transform().basis * Vector3.FORWARD).is_equal_approx(Vector3.LEFT),
		"spawn yaw rotates the forward axis about Y"
	)
	_expect(definition.placement(&"target").is_sonar_metal(), "wrecks read as metal on sonar")
	_expect(not definition.placement(&"anchor").is_sonar_metal(), "anchor is not a sonar body")

	var no_id := _make_definition()
	no_id.site_id = &""
	_expect(not no_id.validation_error().is_empty(), "site id is required")

	var no_terrain := _make_definition()
	no_terrain.terrain = null
	_expect(not no_terrain.validation_error().is_empty(), "terrain is required")

	var bounds_outside := _make_definition()
	bounds_outside.playable_bounds_m = Rect2(-20.0, 100.0, 4.0, 6.0)
	_expect(not bounds_outside.validation_error().is_empty(), "playable bounds must lie inside the terrain")

	var spawn_outside := _make_definition()
	spawn_outside.spawn_position_m = Vector3(50.0, -10.0, 102.0)
	_expect(not spawn_outside.validation_error().is_empty(), "spawn must lie inside the bounds")

	var duplicate_ids := _make_definition()
	duplicate_ids.placements.append(
		_make_placement("target", SitePlacement.Kind.WRECK_DECOY, Vector3(-7.0, -23.0, 104.0))
	)
	_expect(not duplicate_ids.validation_error().is_empty(), "placement ids are unique")

	var placement_outside := _make_definition()
	placement_outside.placements.append(
		_make_placement("far", SitePlacement.Kind.DEBRIS, Vector3(80.0, -23.0, 104.0))
	)
	_expect(not placement_outside.validation_error().is_empty(), "placements must lie inside the bounds")

	var empty_route := _make_definition()
	empty_route.routes.append(_make_route("empty", PackedVector3Array(), 20.0))
	_expect(not empty_route.validation_error().is_empty(), "routes need at least two waypoints")

	var deep_route := _make_definition()
	deep_route.routes.append(
		_make_route("deep", PackedVector3Array([Vector3(-8.0, -12.0, 101.0), Vector3(-8.0, -30.0, 103.0)]), 20.0)
	)
	_expect(not deep_route.validation_error().is_empty(), "route waypoints respect the route maximum depth")


func _expect(condition: bool, label: String) -> void:
	if not condition:
		_failures.append(label)