@tool
extends Node

# Map Validator — Command-line entry point.
#
# Usage:
#   godot --path client --script tools/validate_map.gd -- res://maps/mymap.tscn
#
# The scene path must come after `--` so Godot passes it as a user argument.
#
# Exit codes:
#   0 — All checks passed
#   1 — Warnings only (light suggestions, no blocked items)
#   2 — Errors found (must-fix items)
#
# Runs four validation modules in order:
#   1. Scene structure   — node hierarchy, required groups, LightmapGI, WorldEnvironment
#   2. Polygon count     — total mesh triangles ≤ 50K
#   3. Texture size      — all material textures ≤ 1024×1024
#   4. Light count       — dynamic (non-baked) lights ≤ 4, lightmap bake status
#
# Each module returns a dictionary {pass: bool, errors: [str], warnings: [str]}.

const VALIDATOR_DIR := "res://tools/validate_map/"

enum ExitCode {
	PASS = 0,
	WARNINGS = 1,
	ERRORS = 2,
}


func _ready() -> void:
	var args := OS.get_cmdline_user_args()
	if args.is_empty():
		_print_usage()
		get_tree().quit(ExitCode.ERRORS)
		return

	var scene_path := args[0]

	# Validate path prefix
	if not scene_path.begins_with("res://"):
		push_error("Scene path must be a Godot resource path (res://) — got: ", scene_path)
		get_tree().quit(ExitCode.ERRORS)
		return

	# Load the scene
	var scene := ResourceLoader.load(scene_path, "PackedScene", ResourceLoader.CACHE_MODE_IGNORE)
	if scene == null:
		push_error("Failed to load scene: ", scene_path)
		get_tree().quit(ExitCode.ERRORS)
		return

	print("═══════════════════════════════════════════")
	print("  MAP VALIDATOR")
	print("  Scene: ", scene_path)
	print("═══════════════════════════════════════════")
	print("")

	# Instantiate the scene (in @tool mode this runs in editor)
	var instance_data: Array = _try_instantiate(scene, scene_path)
	var instance: Node = instance_data[0] as Node
	var instantiate_error: String = instance_data[1] as String
	if instance == null:
		push_error(instantiate_error)
		get_tree().quit(ExitCode.ERRORS)
		return

	add_child(instance)

	# Run all validators
	var results: Array[Dictionary] = []
	results.append(_run_module("validate_scene", instance, scene_path))
	results.append(_run_module("validate_polycount", instance, scene_path))
	results.append(_run_module("validate_textures", instance, scene_path))
	results.append(_run_module("validate_lights", instance, scene_path))

	# Summary
	print("")
	print("═══════════════════════════════════════════")
	print("  SUMMARY")
	print("═══════════════════════════════════════════")

	var total_errors := 0
	var total_warnings := 0

	for result in results:
		var label: String = "PASS" if result["pass"] else result["status"]
		print("  [", label, "] ", result["name"])
		total_errors += result["errors"].size()
		total_warnings += result["warnings"].size()

	print("")
	print("  Errors:   ", total_errors)
	print("  Warnings: ", total_warnings)

	if total_errors > 0:
		print("  Result:   FAIL")
		print("")
		get_tree().quit(ExitCode.ERRORS)
	elif total_warnings > 0:
		print("  Result:   PASS (with warnings)")
		print("")
		get_tree().quit(ExitCode.WARNINGS)
	else:
		print("  Result:   PASS")
		print("")
		get_tree().quit(ExitCode.PASS)


# Attempts to instantiate a PackedScene, catching errors gracefully.
func _try_instantiate(scene: PackedScene, path: String) -> Array:
	var err_test := scene.can_instantiate()
	if not err_test:
		return [null, "Scene cannot be instantiated (may depend on other resources): " + path]

	var inst := scene.instantiate(PackedScene.GEN_EDIT_STATE_INSTANCE)
	if inst == null:
		return [null, "Scene instantiate returned null: " + path]
	return [inst, ""]


# Loads a validator script from VALIDATOR_DIR and runs its checks.
func _run_module(name: String, scene_root: Node, scene_path: String) -> Dictionary:
	var script_path := VALIDATOR_DIR.path_join(name + ".gd")
	var script := ResourceLoader.load(script_path, "Script", ResourceLoader.CACHE_MODE_IGNORE)
	if script == null:
		push_error("Failed to load validator module: ", script_path)
		return {
			"name": name,
			"pass": false,
			"status": "ERROR",
			"errors": ["Validator script not found: " + script_path],
			"warnings": [],
		}

	# Instantiate the validator module directly (scripts extend RefCounted)
	if not script.has_method("validate"):
		push_error("Validator module missing validate() method: ", script_path)
		return {
			"name": name,
			"pass": false,
			"status": "ERROR",
			"errors": ["Missing validate() method in " + script_path],
			"warnings": [],
		}

	print("── [", name, "] ────────────────────────────")

	var validator = script.new()
	var result: Dictionary = validator.validate(scene_root, scene_path)

	# Print inline results
	for w in result.get("warnings", []):
		print("  ⚠ ", w)
	for e in result.get("errors", []):
		print("  ✖ ", e)

	var ok: bool = result.get("pass", false)
	if ok:
		print("  ✓ pass")
	else:
		print("  ✖ FAIL")

	print("")
	return result


func _print_usage() -> void:
	print("Map Validator — usage:")
	print("")
	print("  godot --path <project> --script tools/validate_map.gd -- <scene_path>")
	print("")
	print("Examples:")
	print("  godot --path client --script tools/validate_map.gd -- res://maps/de_dust2.tscn")
	print("  godot --path client --script tools/validate_map.gd -- res://maps/my_map.tscn")
	print("")
	print("Exit codes:")
	print("  0 — All checks passed")
	print("  1 — Warnings (non-blocking suggestions)")
	print("  2 — Errors (must-fix items)")
	print("")