extends Node

const EndpointConfig := preload("res://scripts/autoload/api_endpoint_config.gd")
const DEFAULT_QUESTIONS_API_URL := "https://us3q.ranaze.com/api/questions/search"
const DEFAULT_QUESTION_ATTEMPT_API_URL := "https://us3q.ranaze.com/api/questions/attempts/first"
const DEFAULT_QUESTION_API_BASE_URL := "https://us3q.ranaze.com/api/questions"
const DEFAULT_RATINGS_API_URL := "https://us3q.ranaze.com/api/ratings/me"
const DEFAULT_QUESTION_REPORTS_API_URL := "https://us3q.ranaze.com/api/question-reports"
const RETRY_DELAYS := [2, 5, 10, 20, 30]
const REQUEST_TIMEOUT_SECONDS := 30.0
const IMAGE_QUESTION_SEARCH_LIMIT := 200
const ATTEMPT_QUEUE_PATH := "user://pending_question_attempts.json"

signal questions_changed
signal questions_load_failed(message: String)
signal choice_percentages_updated(question_id: String, percentages: Dictionary)
signal ratings_changed
signal question_rating_updated(question_id: String, question_elo: int, rating: Dictionary)
signal question_skipped(question_id: String, correct_choice_id: String, question_elo: int, rating: Dictionary)
signal question_report_submitted(question_id: String, report_id: String)
signal question_report_failed(question_id: String, message: String)

var questions: Array = []
var request: HTTPRequest
var attempt_request: HTTPRequest
var rating_request: HTTPRequest
var report_request: HTTPRequest
var retry_timer: Timer
var attempt_retry_timer: Timer
var questions_api_url := DEFAULT_QUESTIONS_API_URL
var question_attempt_api_url := DEFAULT_QUESTION_ATTEMPT_API_URL
var question_api_base_url := DEFAULT_QUESTION_API_BASE_URL
var ratings_api_url := DEFAULT_RATINGS_API_URL
var question_reports_api_url := DEFAULT_QUESTION_REPORTS_API_URL
var is_loading := false
var last_error := ""
var load_state := "idle"
var retry_attempt := 0
var next_retry_seconds := 0
var overall_elo := 1000
var rank_tier := "Bronze"
var rank_division := 3
var rated_question_count := 0
var category_elos := {}
var last_rating_change := {}
var pending_report_question_id := ""
var attempt_queue: Array = []
var active_attempt_index := -1
var attempt_request_active := false
var questions_request_token := ""
var attempt_request_token := ""
var rating_request_token := ""
var report_request_token := ""
var pending_excluded_question_ids: Array = []
var pending_require_media := false
var pending_step3_system := ""
var pending_difficulty_min := 0
var pending_difficulty_max := 0
var pending_limit := 1
var targeted_fallback_used := false
var image_question_search_attempts := 0

func _ready() -> void:
	questions_api_url = EndpointConfig.resolve(
		str(ProjectSettings.get_setting("step3/questions_api_url", DEFAULT_QUESTIONS_API_URL)),
		"/api/questions/search")
	question_attempt_api_url = EndpointConfig.resolve(
		str(ProjectSettings.get_setting("step3/question_attempt_api_url", DEFAULT_QUESTION_ATTEMPT_API_URL)),
		"/api/questions/attempts/first")
	question_api_base_url = EndpointConfig.resolve(
		str(ProjectSettings.get_setting("step3/question_api_base_url", DEFAULT_QUESTION_API_BASE_URL)),
		"/api/questions")
	ratings_api_url = EndpointConfig.resolve(
		str(ProjectSettings.get_setting("step3/ratings_api_url", DEFAULT_RATINGS_API_URL)),
		"/api/ratings/me")
	question_reports_api_url = EndpointConfig.resolve(
		str(ProjectSettings.get_setting("step3/question_reports_api_url", DEFAULT_QUESTION_REPORTS_API_URL)),
		"/api/question-reports")
	request = HTTPRequest.new()
	request.timeout = REQUEST_TIMEOUT_SECONDS
	request.request_completed.connect(_on_api_questions_loaded)
	add_child(request)

	attempt_request = HTTPRequest.new()
	attempt_request.timeout = REQUEST_TIMEOUT_SECONDS
	attempt_request.request_completed.connect(_on_first_attempt_recorded)
	add_child(attempt_request)

	rating_request = HTTPRequest.new()
	rating_request.timeout = REQUEST_TIMEOUT_SECONDS
	rating_request.request_completed.connect(_on_ratings_loaded)
	add_child(rating_request)

	report_request = HTTPRequest.new()
	report_request.timeout = REQUEST_TIMEOUT_SECONDS
	report_request.request_completed.connect(_on_question_report_submitted)
	add_child(report_request)

	retry_timer = Timer.new()
	retry_timer.one_shot = true
	retry_timer.timeout.connect(_on_retry_timer_timeout)
	add_child(retry_timer)

	attempt_retry_timer = Timer.new()
	attempt_retry_timer.one_shot = true
	attempt_retry_timer.timeout.connect(_process_attempt_queue)
	add_child(attempt_retry_timer)

	_load_attempt_queue()
	if not AuthState.auth_changed.is_connected(_on_auth_changed_for_attempt_queue):
		AuthState.auth_changed.connect(_on_auth_changed_for_attempt_queue)
	_process_attempt_queue()


func load_questions_from_api(reset_retry: bool = true, excluded_question_ids: Array = [], require_media: bool = false,
		step3_system: String = "", difficulty_min: int = 0, difficulty_max: int = 0, requested_limit: int = 1) -> void:
	if not AuthState.can_send_authenticated_request():
		_set_load_error("Login required before loading questions.", false)
		return

	if reset_retry:
		pending_excluded_question_ids = excluded_question_ids.duplicate()
		pending_require_media = require_media
		pending_step3_system = step3_system
		pending_difficulty_min = difficulty_min
		pending_difficulty_max = difficulty_max
		pending_limit = clampi(requested_limit, 1, 40)
		targeted_fallback_used = false
		image_question_search_attempts = 0
		retry_attempt = 0
		next_retry_seconds = 0
		retry_timer.stop()
		if is_loading or request.get_http_client_status() != HTTPClient.STATUS_DISCONNECTED:
			request.cancel_request()
			is_loading = false
			call_deferred("load_questions_from_api", false, pending_excluded_question_ids, pending_require_media)
			return
	elif is_loading or request.get_http_client_status() != HTTPClient.STATUS_DISCONNECTED:
		# A late timer or repeated click must not turn an active request into an
		# immediate ERR_BUSY failure.
		return

	var should_load_ratings := load_state == "idle"
	is_loading = true
	load_state = "retrying" if retry_attempt > 0 else "loading"
	last_error = ""
	questions.clear()
	questions_changed.emit()
	if should_load_ratings:
		load_ratings_from_api()

	questions_request_token = AuthState.access_token
	var headers := PackedStringArray([
		"Content-Type: application/json",
		"Authorization: Bearer %s" % questions_request_token
	])
	var payload := {
		"limit": pending_limit,
		"supportsChoicePools": true,
		"requireMedia": pending_require_media,
		"excludeExternalIds": pending_excluded_question_ids
	}
	if not pending_step3_system.is_empty():
		payload["step3System"] = pending_step3_system
	if pending_difficulty_min > 0:
		payload["difficultyMin"] = pending_difficulty_min
	if pending_difficulty_max > 0:
		payload["difficultyMax"] = pending_difficulty_max
	var err := request.request(questions_api_url, headers, HTTPClient.METHOD_POST, JSON.stringify(payload))
	if err != OK:
		_set_load_error("Unable to connect to the question service.")


func _on_api_questions_loaded(result: int, response_code: int, _headers: PackedStringArray, body: PackedByteArray) -> void:
	is_loading = false
	if response_code == 401:
		AuthState.handle_unauthorized(questions_request_token)
	if result != HTTPRequest.RESULT_SUCCESS or response_code < 200 or response_code >= 300:
		var message := "The connection to the question service was interrupted."
		if response_code > 0:
			message = "Questions API request failed with status %d." % response_code
		_set_load_error(message, _is_transient_question_failure(result, response_code))
		return

	var parsed: Variant = JSON.parse_string(body.get_string_from_utf8())
	if typeof(parsed) != TYPE_ARRAY:
		_set_load_error("Questions API response was not an array.", false)
		return

	var api_questions: Array = []
	for item in parsed:
		var normalized := _normalize_api_question(item)
		if _is_valid_question(normalized):
			api_questions.append(normalized)

	if api_questions.is_empty():
		if not pending_step3_system.is_empty() and (pending_difficulty_min > 0 or pending_difficulty_max > 0) and not targeted_fallback_used:
			targeted_fallback_used = true
			pending_difficulty_min = 0
			pending_difficulty_max = 0
			call_deferred("load_questions_from_api", false, pending_excluded_question_ids, pending_require_media)
			return
		_set_load_error("Questions API returned no usable questions.", false)
		return
	if pending_require_media and not _contains_question_with_media(api_questions):
		for question in api_questions:
			var question_id := str(question.get("id", ""))
			if question_id != "" and not pending_excluded_question_ids.has(question_id):
				pending_excluded_question_ids.append(question_id)
		image_question_search_attempts += api_questions.size()
		if image_question_search_attempts >= IMAGE_QUESTION_SEARCH_LIMIT:
			_set_load_error("No question with an image was found.", false)
			return
		call_deferred("load_questions_from_api", false, pending_excluded_question_ids, true)
		return

	questions = api_questions
	last_error = ""
	load_state = "ready"
	retry_attempt = 0
	next_retry_seconds = 0
	retry_timer.stop()
	questions_changed.emit()


func load_targeted_questions(step3_system: String, question_count: int, difficulty_min: int = 0, difficulty_max: int = 0) -> void:
	load_questions_from_api(true, [], false, step3_system, difficulty_min, difficulty_max, question_count)


func retry_now() -> void:
	retry_attempt = 0
	next_retry_seconds = 0
	retry_timer.stop()
	if is_loading or request.get_http_client_status() != HTTPClient.STATUS_DISCONNECTED:
		request.cancel_request()
		is_loading = false
	call_deferred("load_questions_from_api", false, pending_excluded_question_ids, pending_require_media)


func load_next_random_question(excluded_question_ids: Array) -> void:
	load_questions_from_api(true, excluded_question_ids)


func load_image_question_for_testing() -> void:
	load_questions_from_api(true, [], true)


func _contains_question_with_media(question_list: Array) -> bool:
	for question in question_list:
		var media: Array = question.get("media", [])
		if not media.is_empty():
			return true
	return false


func clear_questions() -> void:
	if request != null:
		request.cancel_request()
	if attempt_request != null:
		attempt_request.cancel_request()
	if rating_request != null:
		rating_request.cancel_request()
	if report_request != null:
		report_request.cancel_request()
	if retry_timer != null:
		retry_timer.stop()
	if attempt_retry_timer != null:
		attempt_retry_timer.stop()
	attempt_request_active = false
	active_attempt_index = -1
	questions.clear()
	is_loading = false
	last_error = ""
	load_state = "idle"
	retry_attempt = 0
	next_retry_seconds = 0
	overall_elo = 1000
	rank_tier = "Bronze"
	rank_division = 3
	rated_question_count = 0
	category_elos = {}
	last_rating_change = {}
	pending_report_question_id = ""
	pending_excluded_question_ids.clear()
	pending_require_media = false
	pending_step3_system = ""
	pending_difficulty_min = 0
	pending_difficulty_max = 0
	pending_limit = 1
	targeted_fallback_used = false
	image_question_search_attempts = 0
	questions_changed.emit()
	ratings_changed.emit()


func record_first_attempt(question_id: String, choice_id: String, presented_choice_ids: Array = [], duration_seconds: int = 0, met_time_limit: bool = true) -> void:
	if not AuthState.can_send_authenticated_request() or question_id == "" or choice_id == "":
		return
	_enqueue_attempt("answer", question_id, choice_id, presented_choice_ids, duration_seconds, met_time_limit)


func skip_question(question_id: String) -> void:
	if not AuthState.can_send_authenticated_request() or question_id == "":
		return
	_enqueue_attempt("skip", question_id, "")


func submit_question_report(question_id: String, category: String, details: String) -> bool:
	if not AuthState.can_send_authenticated_request() or question_id == "":
		question_report_failed.emit(question_id, "Login is required to submit a report.")
		return false
	if report_request.get_http_client_status() != HTTPClient.STATUS_DISCONNECTED:
		question_report_failed.emit(question_id, "Another report is still being submitted.")
		return false

	report_request_token = AuthState.access_token
	var headers := PackedStringArray([
		"Content-Type: application/json",
		"Authorization: Bearer %s" % report_request_token
	])
	var payload := {
		"questionExternalId": question_id,
		"category": category,
		"details": details
	}
	pending_report_question_id = question_id
	var err := report_request.request(
		question_reports_api_url,
		headers,
		HTTPClient.METHOD_POST,
		JSON.stringify(payload)
	)
	if err != OK:
		pending_report_question_id = ""
		question_report_failed.emit(question_id, "The report could not be submitted. Please try again.")
		return false
	return true


func load_ratings_from_api() -> void:
	if not AuthState.can_send_authenticated_request():
		return
	rating_request_token = AuthState.access_token
	var headers := PackedStringArray([
		"Authorization: Bearer %s" % rating_request_token
	])
	var err := rating_request.request(ratings_api_url, headers, HTTPClient.METHOD_GET)
	if err != OK:
		push_warning("Failed to request rating profile.")


func get_all_questions() -> Array:
	return questions.duplicate(true)


func get_systems() -> Array[String]:
	var system_names: Array[String] = []
	for question in questions:
		var system_name := str(question.get("system", "General"))
		if not system_names.has(system_name):
			system_names.append(system_name)
	system_names.sort()
	return system_names


func get_questions_for_system(system_name: String) -> Array:
	if system_name == "All Systems":
		return get_all_questions()

	var filtered: Array = []
	for question in questions:
		if str(question.get("step3_system", question.get("system", ""))) == system_name or str(question.get("system", "")) == system_name:
			filtered.append(question.duplicate(true))
	return filtered


func build_block(system_name: String, block_size: int) -> Array:
	var pool := get_questions_for_system(system_name)
	pool.shuffle()
	return pool.slice(0, min(block_size, pool.size()))


func has_questions() -> bool:
	return not questions.is_empty()


func _set_load_error(message: String, schedule_retry: bool = true) -> void:
	is_loading = false
	last_error = message
	push_warning(message)
	if schedule_retry and not AuthState.access_token.is_empty():
		_schedule_retry()
	else:
		load_state = "failed"
		next_retry_seconds = 0
	questions_load_failed.emit(message)
	questions_changed.emit()


func _is_transient_question_failure(result: int, response_code: int) -> bool:
	if result != HTTPRequest.RESULT_SUCCESS:
		return true
	return response_code == 0 or response_code == 408 or response_code == 425 \
		or response_code == 429 or response_code >= 500


func _schedule_retry() -> void:
	var delay_index := retry_attempt
	if delay_index >= RETRY_DELAYS.size():
		delay_index = RETRY_DELAYS.size() - 1
	next_retry_seconds = int(RETRY_DELAYS[delay_index])
	retry_attempt += 1
	load_state = "retrying"
	retry_timer.start(float(next_retry_seconds))


func _on_retry_timer_timeout() -> void:
	next_retry_seconds = 0
	if is_loading or request.get_http_client_status() != HTTPClient.STATUS_DISCONNECTED:
		retry_timer.start(1.0)
		return
	load_questions_from_api(false)


func _enqueue_attempt(kind: String, question_id: String, choice_id: String, presented_choice_ids: Array = [], duration_seconds: int = 0, met_time_limit: bool = true) -> void:
	var account := AuthState.username.strip_edges()
	if account == "":
		return
	for queued in attempt_queue:
		if str(queued.get("account", "")) == account and str(queued.get("question_id", "")) == question_id:
			return
	attempt_queue.append({
		"account": account,
		"kind": kind,
		"question_id": question_id,
		"choice_id": choice_id,
		"presented_choice_ids": presented_choice_ids.duplicate(),
		"duration_seconds": maxi(0, duration_seconds),
		"met_time_limit": met_time_limit,
		"study_session_id": StudySessionService.active_session_id,
		"retry_count": 0
	})
	_save_attempt_queue()
	_process_attempt_queue()


func _process_attempt_queue() -> void:
	if attempt_request_active or attempt_queue.is_empty() or not AuthState.can_send_authenticated_request():
		return
	if attempt_retry_timer != null and not attempt_retry_timer.is_stopped():
		return

	active_attempt_index = -1
	for index in range(attempt_queue.size()):
		if str(attempt_queue[index].get("account", "")) == AuthState.username:
			active_attempt_index = index
			break
	if active_attempt_index < 0:
		return

	var queued: Dictionary = attempt_queue[active_attempt_index]
	attempt_request_token = AuthState.access_token
	var headers := PackedStringArray([
		"Content-Type: application/json",
		"Authorization: Bearer %s" % attempt_request_token
	])
	var question_id := str(queued.get("question_id", ""))
	var url := question_attempt_api_url
	var body := JSON.stringify({
		"questionExternalId": question_id,
		"choiceId": str(queued.get("choice_id", "")),
		"presentedChoiceIds": queued.get("presented_choice_ids", []),
		"durationSeconds": int(queued.get("duration_seconds", 0)),
		"metTimeLimit": bool(queued.get("met_time_limit", true))
	})
	var study_session_id := str(queued.get("study_session_id", ""))
	if not study_session_id.is_empty():
		var decoded: Dictionary = JSON.parse_string(body)
		decoded["studySessionId"] = study_session_id
		body = JSON.stringify(decoded)
	if str(queued.get("kind", "answer")) == "skip":
		url = "%s/%s/skip" % [question_api_base_url.rstrip("/"), question_id.uri_encode()]
		body = ""

	attempt_request_active = true
	var err := attempt_request.request(url, headers, HTTPClient.METHOD_POST, body)
	if err != OK:
		attempt_request_active = false
		_schedule_attempt_retry()


func _schedule_attempt_retry() -> void:
	if active_attempt_index < 0 or active_attempt_index >= attempt_queue.size():
		return
	var queued: Dictionary = attempt_queue[active_attempt_index]
	var retry_count := int(queued.get("retry_count", 0)) + 1
	queued["retry_count"] = retry_count
	attempt_queue[active_attempt_index] = queued
	_save_attempt_queue()
	var delay_index: int = min(retry_count - 1, RETRY_DELAYS.size() - 1)
	attempt_retry_timer.start(float(RETRY_DELAYS[delay_index]))


func _remove_active_attempt() -> void:
	if active_attempt_index >= 0 and active_attempt_index < attempt_queue.size():
		attempt_queue.remove_at(active_attempt_index)
	_save_attempt_queue()
	active_attempt_index = -1


func _on_first_attempt_recorded(result: int, response_code: int, _headers: PackedStringArray, body: PackedByteArray) -> void:
	attempt_request_active = false
	if active_attempt_index < 0 or active_attempt_index >= attempt_queue.size():
		return
	var queued: Dictionary = attempt_queue[active_attempt_index]
	var succeeded := result == HTTPRequest.RESULT_SUCCESS and response_code >= 200 and response_code < 300
	if not succeeded:
		if response_code == 401:
			AuthState.handle_unauthorized(attempt_request_token)
			active_attempt_index = -1
		elif response_code in [400, 403, 404]:
			push_warning("Discarding invalid question attempt with status %d." % response_code)
			_remove_active_attempt()
			_process_attempt_queue()
		else:
			_schedule_attempt_retry()
		return

	var parsed: Variant = JSON.parse_string(body.get_string_from_utf8())
	if typeof(parsed) != TYPE_DICTIONARY:
		_schedule_attempt_retry()
		return

	_remove_active_attempt()
	if str(queued.get("kind", "answer")) == "skip":
		_apply_skip_response(parsed)
	else:
		_apply_first_attempt_response(parsed)
	_process_attempt_queue()


func _apply_first_attempt_response(parsed: Dictionary) -> void:

	var question_id := str(parsed.get("questionExternalId", parsed.get("question_external_id", "")))
	var percentages: Dictionary = parsed.get("choiceSelectionPercentages", parsed.get("choice_selection_percentages", {}))
	if question_id == "":
		return

	_update_question_percentages(question_id, percentages)
	var question_elo := int(parsed.get("questionElo", parsed.get("question_elo", 1000)))
	var rating: Dictionary = parsed.get("rating", {})
	_update_question_elo(question_id, question_elo)
	_apply_rating_change(rating)
	CreditsService.apply_award_response(parsed)
	DailyMissionService.apply_response(parsed)
	# Let Tutor users inspect the final answer before the summary replaces the player.
	StudySessionService.apply_response(parsed, true)
	choice_percentages_updated.emit(question_id, percentages)
	question_rating_updated.emit(question_id, question_elo, rating)


func _apply_skip_response(parsed: Dictionary) -> void:
	var question_id := str(parsed.get("questionExternalId", parsed.get("question_external_id", "")))
	var correct_choice_id := str(parsed.get("correctChoiceId", parsed.get("correct_choice_id", "")))
	var percentages: Dictionary = parsed.get("choiceSelectionPercentages", parsed.get("choice_selection_percentages", {}))
	var question_elo := int(parsed.get("questionElo", parsed.get("question_elo", 1000)))
	var rating: Dictionary = parsed.get("rating", {})
	if question_id == "":
		return

	_update_question_percentages(question_id, percentages)
	_update_question_elo(question_id, question_elo)
	_apply_rating_change(rating)
	choice_percentages_updated.emit(question_id, percentages)
	question_skipped.emit(question_id, correct_choice_id, question_elo, rating)


func _on_auth_changed_for_attempt_queue() -> void:
	if AuthState.access_token.is_empty():
		if attempt_retry_timer != null:
			attempt_retry_timer.stop()
		return
	_process_attempt_queue()


func _load_attempt_queue() -> void:
	attempt_queue = []
	if not FileAccess.file_exists(ATTEMPT_QUEUE_PATH):
		return
	var parsed: Variant = JSON.parse_string(FileAccess.get_file_as_string(ATTEMPT_QUEUE_PATH))
	if typeof(parsed) != TYPE_ARRAY:
		return
	for item in parsed:
		if typeof(item) != TYPE_DICTIONARY:
			continue
		var account := str(item.get("account", "")).strip_edges()
		var question_id := str(item.get("question_id", "")).strip_edges()
		var kind := str(item.get("kind", "answer"))
		if account == "" or question_id == "" or kind not in ["answer", "skip"]:
			continue
		attempt_queue.append({
			"account": account,
			"kind": kind,
			"question_id": question_id,
			"choice_id": str(item.get("choice_id", "")),
			"presented_choice_ids": item.get("presented_choice_ids", []).duplicate(),
			"retry_count": max(0, int(item.get("retry_count", 0)))
		})


func _save_attempt_queue() -> void:
	var file := FileAccess.open(ATTEMPT_QUEUE_PATH, FileAccess.WRITE)
	if file == null:
		push_warning("Could not persist pending question attempts.")
		return
	file.store_string(JSON.stringify(attempt_queue))


func _on_question_report_submitted(result: int, response_code: int, _headers: PackedStringArray, body: PackedByteArray) -> void:
	var parsed: Variant = JSON.parse_string(body.get_string_from_utf8())
	var question_id := ""
	if typeof(parsed) == TYPE_DICTIONARY:
		question_id = str(parsed.get("questionExternalId", parsed.get("question_external_id", "")))
	if question_id == "":
		question_id = pending_report_question_id
	pending_report_question_id = ""
	if response_code == 401:
		AuthState.handle_unauthorized(report_request_token)

	if result != HTTPRequest.RESULT_SUCCESS or response_code < 200 or response_code >= 300:
		var message := "The report could not be submitted. Please try again."
		if typeof(parsed) == TYPE_DICTIONARY:
			message = str(parsed.get("detail", parsed.get("title", message)))
		elif typeof(parsed) == TYPE_STRING and not str(parsed).strip_edges().is_empty():
			message = str(parsed).strip_edges()
		question_report_failed.emit(question_id, message)
		return

	if typeof(parsed) != TYPE_DICTIONARY:
		question_report_failed.emit(question_id, "The report API returned an invalid response.")
		return

	var report_id := str(parsed.get("id", ""))
	if question_id == "" or report_id == "":
		question_report_failed.emit(question_id, "The report API returned an incomplete response.")
		return
	question_report_submitted.emit(question_id, report_id)


func _on_ratings_loaded(result: int, response_code: int, _headers: PackedStringArray, body: PackedByteArray) -> void:
	if response_code == 401:
		AuthState.handle_unauthorized(rating_request_token)
	if result != HTTPRequest.RESULT_SUCCESS or response_code < 200 or response_code >= 300:
		push_warning("Ratings API request failed with status %d." % response_code)
		return

	var parsed: Variant = JSON.parse_string(body.get_string_from_utf8())
	if typeof(parsed) != TYPE_DICTIONARY:
		push_warning("Ratings API response was not an object.")
		return

	overall_elo = int(parsed.get("overallElo", parsed.get("overall_elo", 1000)))
	rank_tier = str(parsed.get("tier", rank_tier))
	rank_division = int(parsed.get("tierDivision", parsed.get("tier_division", rank_division)))
	rated_question_count = int(parsed.get("ratedQuestionCount", parsed.get("rated_question_count", 0)))
	category_elos = parsed.get("categoryElos", parsed.get("category_elos", {}))
	ratings_changed.emit()


func _update_question_percentages(question_id: String, percentages: Dictionary) -> void:
	for index in range(questions.size()):
		var question: Dictionary = questions[index]
		if str(question.get("id", "")) == question_id:
			question["choice_selection_percentages"] = percentages
			questions[index] = question
			return


func _update_question_elo(question_id: String, question_elo: int) -> void:
	for index in range(questions.size()):
		var question: Dictionary = questions[index]
		if str(question.get("id", "")) == question_id:
			question["question_elo"] = question_elo
			questions[index] = question
			return


func _apply_rating_change(rating: Dictionary) -> void:
	if rating.is_empty():
		return
	last_rating_change = rating
	overall_elo = int(rating.get("userOverallElo", rating.get("user_overall_elo", overall_elo)))
	var category := str(rating.get("category", ""))
	if category != "":
		category_elos[category] = int(rating.get("userCategoryElo", rating.get("user_category_elo", category_elos.get(category, 1000))))
	rated_question_count += 1 if bool(rating.get("rated", false)) else 0
	ratings_changed.emit()


func _is_valid_question(item: Variant) -> bool:
	if typeof(item) != TYPE_DICTIONARY:
		return false
	var required := ["id", "stem", "lead_in", "choices", "correct_choice_id", "explanation", "system", "discipline"]
	for key in required:
		if not item.has(key):
			return false
	return typeof(item["choices"]) == TYPE_ARRAY and item["choices"].size() >= 2


func _normalize_api_question(item: Variant) -> Dictionary:
	if typeof(item) != TYPE_DICTIONARY:
		return {}

	var normalized := {
		"id": str(item.get("externalId", item.get("id", ""))),
		"api_id": str(item.get("id", "")),
		"stem": str(item.get("stem", "")),
		"lead_in": str(item.get("leadIn", item.get("lead_in", ""))),
		"choices": item.get("choices", []),
		"correct_choice_id": str(item.get("correctChoiceId", item.get("correct_choice_id", ""))),
		"explanation": str(item.get("explanation", "")),
		"key_takeaway": str(item.get("keyTakeaway", item.get("key_takeaway", ""))),
		"usmle_pearl": str(item.get("usmlePearl", item.get("usmle_pearl", ""))),
		"review_followups": _normalize_review_followups(item.get("reviewFollowups", item.get("review_followups", []))),
		"choice_explanations": item.get("choiceExplanations", item.get("choice_explanations", {})),
		"wrong_answer_followups": item.get("wrongAnswerFollowups", item.get("wrong_answer_followups", {})),
		"choice_selection_percentages": item.get("choiceSelectionPercentages", item.get("choice_selection_percentages", {})),
		"discipline": str(item.get("discipline", "")),
		"system": str(item.get("system", "")),
		"step3_system": str(item.get("step3System", item.get("step3_system", ""))),
		"performance_category": str(item.get("performanceCategory", item.get("performance_category", ""))),
		"difficulty": int(item.get("difficulty", 1)),
		"question_elo": int(item.get("questionElo", item.get("question_elo", 1000))),
		"is_bookmarked": bool(item.get("isBookmarked", item.get("is_bookmarked", false))),
		"labs": item.get("labs", []),
		"media": item.get("media", []),
		"tags": item.get("tags", []),
		"references": _normalize_references(item.get("references", []))
	}
	return normalized


func normalize_api_question(item: Variant) -> Dictionary:
	return _normalize_api_question(item)


func _normalize_review_followups(raw_followups: Variant) -> Array:
	var normalized: Array = []
	if typeof(raw_followups) != TYPE_ARRAY:
		return normalized
	for raw_followup in raw_followups:
		if typeof(raw_followup) != TYPE_DICTIONARY:
			continue
		normalized.append({
			"prompt": str(raw_followup.get("prompt", "")).strip_edges(),
			"choices": raw_followup.get("choices", []),
			"correct_choice_id": str(raw_followup.get("correctChoiceId", raw_followup.get("correct_choice_id", ""))),
			"teaching_point": str(raw_followup.get("teachingPoint", raw_followup.get("teaching_point", ""))).strip_edges()
		})
	return normalized


func _normalize_references(raw_references: Variant) -> Array:
	var normalized: Array = []
	if typeof(raw_references) != TYPE_ARRAY:
		return normalized
	for raw_reference in raw_references:
		if typeof(raw_reference) != TYPE_DICTIONARY:
			continue
		normalized.append({
			"title": str(raw_reference.get("title", raw_reference.get("Title", ""))).strip_edges(),
			"publisher": str(raw_reference.get("publisher", raw_reference.get("Publisher", ""))).strip_edges(),
			"url": str(raw_reference.get("url", raw_reference.get("Url", ""))).strip_edges(),
			"supports": str(raw_reference.get("supports", raw_reference.get("Supports", ""))).strip_edges(),
			"accessed_on": str(raw_reference.get("accessedOn", raw_reference.get("accessed_on", raw_reference.get("AccessedOn", "")))).strip_edges(),
			"reviewer": str(raw_reference.get("reviewer", raw_reference.get("Reviewer", ""))).strip_edges()
		})
	return normalized