<?php

declare(strict_types=1);

namespace OCA\EducAI\Controller;

use Exception;
use OCA\EducAI\Db\BotMapper;
use OCA\EducAI\Db\BotSourceMapper;
use OCA\EducAI\Db\QueuedRequest;
use OCA\EducAI\Db\Settings;
use OCA\EducAI\Service\BotService;
use OCA\EducAI\Service\RateLimitService;
use OCA\EducAI\Service\RagIngestionService;
use OCA\EducAI\Service\AppIconService;
use OCA\EducAI\Service\SettingsService;
use OCA\EducAI\Service\LLMClient;
use OCA\EducAI\Webhook\TalkHandler;
use OCP\App\IAppManager;
use OCP\AppFramework\Controller;
use OCP\AppFramework\Db\DoesNotExistException;
use OCP\AppFramework\Http\DataResponse;
use OCP\BackgroundJob\IJobList;
use OCP\IGroupManager;
use OCP\IRequest;
use OCP\IURLGenerator;
use OCP\IUserSession;
use Psr\Log\LoggerInterface;

class SettingsController extends Controller {
	private const DEFAULT_TEMPERATURE_NOT_PROVIDED = '__educai_default_temperature_not_provided__';

    private SettingsService $settingsService;
    private LLMClient $llmClient;
	private RateLimitService $rateLimitService;
	private RagIngestionService $ragIngestionService;
	private BotSourceMapper $botSourceMapper;
	private IJobList $jobList;
	private BotService $botService;
	private BotMapper $botMapper;
	private TalkHandler $talkHandler;
	private AppIconService $appIconService;
	private IURLGenerator $urlGenerator;
	private IGroupManager $groupManager;
	private IUserSession $userSession;
	private IAppManager $appManager;
	private LoggerInterface $logger;

	public function __construct(
		string $appName,
		IRequest $request,
		SettingsService $settingsService,
		LLMClient $llmClient,
		RateLimitService $rateLimitService,
		RagIngestionService $ragIngestionService,
		BotSourceMapper $botSourceMapper,
		IJobList $jobList,
		BotService $botService,
		BotMapper $botMapper,
		TalkHandler $talkHandler,
		AppIconService $appIconService,
		IURLGenerator $urlGenerator,
		IGroupManager $groupManager,
		IUserSession $userSession,
		IAppManager $appManager,
		LoggerInterface $logger
	) {
		parent::__construct($appName, $request);
		$this->settingsService = $settingsService;
		$this->llmClient = $llmClient;
		$this->rateLimitService = $rateLimitService;
		$this->ragIngestionService = $ragIngestionService;
		$this->botSourceMapper = $botSourceMapper;
		$this->jobList = $jobList;
		$this->botService = $botService;
		$this->botMapper = $botMapper;
		$this->talkHandler = $talkHandler;
		$this->appIconService = $appIconService;
		$this->urlGenerator = $urlGenerator;
		$this->groupManager = $groupManager;
		$this->userSession = $userSession;
		$this->appManager = $appManager;
		$this->logger = $logger;
	}

	/**
	 * @NoAdminRequired
	 * Get settings (masked for non-admin users)
	 */
	public function index(): DataResponse {
		try {
			$settings = $this->settingsService->getSettings();
			return new DataResponse($this->buildSettingsPayload($settings));
		} catch (Exception $e) {
			$this->logger->error('Failed to get settings: ' . $e->getMessage());
			return new DataResponse(['error' => $e->getMessage()], 500);
		}
	}

	/**
	 * @AdminRequired
	 * Update global settings (admin-only)
	 */
    public function update(
        string $apiKey,
        string $apiEndpoint,
        string $defaultModel,
        $defaultTemperature = self::DEFAULT_TEMPERATURE_NOT_PROVIDED,
        ?string $webhookSecret = null,
        string $apiProvider = 'custom',
        ?bool $allowMultipleModels = null,
		?array $allowedModels = null,
		?string $embeddingApiEndpoint = null,
		?string $embeddingApiKey = null,
		?string $embeddingModel = null,
		?int $ragChunkSize = null,
		?int $ragChunkOverlap = null,
		?bool $ragEnabled = null,
		?bool $catalogueEnabled = null,
		?string $catalogueApiEndpoint = null,
		?int $catalogueReindexHours = null,
		?bool $doclingEnabled = null,
		?string $doclingApiEndpoint = null,
		?string $doclingApiKey = null,
		?string $visionApiEndpoint = null,
		?string $visionApiKey = null,
		?string $visionModel = null,
		?string $speechApiEndpoint = null,
		?string $speechApiKey = null,
		?string $speechModel = null,
		?bool $rateLimitEnabled = null,
		?int $rateLimitSecond = null,
		?int $rateLimitMinute = null,
		?int $rateLimitHour = null,
		?int $rateLimitDay = null,
		?string $rateLimitQueueMessage = null,
		?int $conversationContextTokens = null,
		?string $embeddingRateLimitMode = null,
		?int $embeddingRateLimitSecond = null,
		?int $embeddingRateLimitMinute = null,
		?int $embeddingRateLimitHour = null,
		?int $embeddingRateLimitDay = null,
		?string $secondaryApiEndpoint = null,
		?string $secondaryApiKey = null,
		?string $fallbackModel = null,
		?int $llmChatTimeout = null,
		?int $llmStreamTimeout = null,
		?int $llmModelsTimeout = null,
		?string $appIconUrl = null,
		?string $appIconMode = null,
		?string $appIconBlackUrl = null,
		?string $appIconWhiteUrl = null
	): DataResponse {
		try {
			$this->logger->info('EducAI Settings Update - catalogueApiEndpoint: ' . var_export($catalogueApiEndpoint, true) . ', catalogueEnabled: ' . var_export($catalogueEnabled, true));
			$beforeRateLimitConfig = $this->extractRateLimitConfig($this->settingsService->getSettings());
			$settings = $this->settingsService->updateSettings(
				$apiProvider,
				$apiKey,
				$apiEndpoint,
				$defaultModel,
				$defaultTemperature === self::DEFAULT_TEMPERATURE_NOT_PROVIDED ? null : $defaultTemperature,
                $webhookSecret,
                $allowMultipleModels,
				$allowedModels,
				$embeddingApiEndpoint,
				$embeddingApiKey,
				$embeddingModel,
				$ragChunkSize,
				$ragChunkOverlap,
				$ragEnabled,
				$catalogueEnabled,
				$catalogueApiEndpoint,
				$catalogueReindexHours,
				$doclingEnabled,
				$doclingApiEndpoint,
				$doclingApiKey,
				$visionApiEndpoint,
				$visionApiKey,
				$visionModel,
				$speechApiEndpoint,
				$speechApiKey,
				$speechModel,
				$rateLimitEnabled,
				$rateLimitSecond,
				$rateLimitMinute,
				$rateLimitHour,
				$rateLimitDay,
				$rateLimitQueueMessage,
				$conversationContextTokens,
				$embeddingRateLimitMode,
				$embeddingRateLimitSecond,
				$embeddingRateLimitMinute,
				$embeddingRateLimitHour,
				$embeddingRateLimitDay,
				$secondaryApiEndpoint,
				$secondaryApiKey,
				$fallbackModel,
				$llmChatTimeout,
				$llmStreamTimeout,
				$llmModelsTimeout,
				$appIconUrl,
				$appIconMode,
				$appIconBlackUrl,
				$appIconWhiteUrl
			);

			$afterRateLimitConfig = $this->extractRateLimitConfig($settings);
			if ($beforeRateLimitConfig !== $afterRateLimitConfig) {
				$this->rateLimitService->resetState();
			}
			
			return new DataResponse($this->buildSettingsPayload($settings));
		} catch (Exception $e) {
			$this->logger->error('Failed to update settings: ' . $e->getMessage());
			return new DataResponse(['error' => $e->getMessage()], 400);
		}
	}

    /**
     * @NoAdminRequired
     * List models from the configured provider
     */
	public function models(): DataResponse {
		try {
			$modelOptions = $this->llmClient->listModelOptions();
			return new DataResponse([
				'models' => array_values(array_map(static fn (array $option): string => (string)$option['id'], $modelOptions)),
				'model_options' => $modelOptions,
			]);
		} catch (Exception $e) {
			$this->logger->error('Failed to list models: ' . $e->getMessage());
			return new DataResponse(['error' => $e->getMessage()], 400);
		}
	}

	/**
	 * @NoAdminRequired
	 * List groups for selection when creating bots
	 */
	public function groups(): DataResponse {
		try {
			$groupManager = $this->groupManager;
			$currentUser = $this->userSession->getUser();

			$groups = [];
			// Prefer a broad search (limited) if available
			if (method_exists($groupManager, 'search')) {
				// Some implementations return array of IGroup, others array of strings
				$result = $groupManager->search('', 200);
				foreach ($result as $g) {
					if (is_object($g) && method_exists($g, 'getGID')) {
						$groups[] = [
							'id' => $g->getGID(),
							'displayName' => method_exists($g, 'getDisplayName') ? ($g->getDisplayName() ?? $g->getGID()) : $g->getGID(),
						];
					} else {
						$gid = (string)$g;
						$groups[] = [
							'id' => $gid,
							'displayName' => $gid,
						];
					}
				}
			} elseif (method_exists($groupManager, 'getGroups')) {
				$result = $groupManager->getGroups('', 200, 0);
				foreach ($result as $g) {
					$groups[] = [
						'id' => $g->getGID(),
						'displayName' => $g->getDisplayName() ?? $g->getGID(),
					];
				}
			}

			// Fallback to user's own groups if listing is restricted or empty
			if (count($groups) === 0 && $currentUser !== null) {
				$userGroups = $groupManager->getUserGroups($currentUser);
				foreach ($userGroups as $g) {
					$groups[] = [
						'id' => $g->getGID(),
						'displayName' => $g->getDisplayName() ?? $g->getGID(),
					];
				}
			}

			return new DataResponse(['groups' => $groups]);
		} catch (Exception $e) {
			$this->logger->error('Failed to list groups: ' . $e->getMessage());
			return new DataResponse(['error' => $e->getMessage()], 400);
		}
	}

	/**
	 * @NoAdminRequired
	 * List teams (Circles) available to the current user
	 */
	public function teams(): DataResponse {
		try {
			if (!class_exists('\\OCA\\Circles\\Api\\v1\\Circles')) {
				return new DataResponse(['teams' => []]);
			}

			$currentUser = $this->userSession->getUser();
			if ($currentUser === null) {
				return new DataResponse(['teams' => []]);
			}

			$appManager = $this->appManager;
			if (method_exists($appManager, 'isEnabledForUser')) {
				try {
					if (!$appManager->isEnabledForUser('circles', $currentUser)) {
						return new DataResponse(['teams' => []]);
					}
				} catch (\Throwable $e) {
					$this->logger->debug('Unable to verify Circles availability for user', [
						'exception' => $e,
					]);
				}
			}

			$userId = method_exists($currentUser, 'getUID') ? $currentUser->getUID() : null;
			if ($userId === null) {
				return new DataResponse(['teams' => []]);
			}

			$circles = \OCA\Circles\Api\v1\Circles::joinedCircles($userId, true);
			$teams = [];
			foreach ($circles as $circle) {
				try {
					$source = method_exists($circle, 'getSource') ? $circle->getSource() : null;
					if ($source !== null && !in_array($source, [16, 10001], true)) {
						continue;
					}
					$displayName = '';
					if (method_exists($circle, 'getDisplayName')) {
						$displayName = (string)$circle->getDisplayName();
					}
					if ($displayName === '' && method_exists($circle, 'getName')) {
						$displayName = (string)$circle->getName();
					}
					if ($displayName === '') {
						$displayName = (string)$circle->getSingleId();
					}
					$teams[] = [
						'id' => method_exists($circle, 'getSingleId') ? $circle->getSingleId() : $displayName,
						'displayName' => $displayName,
					];
				} catch (\Throwable $e) {
					$this->logger->debug('Failed to process circle for teams list', [
						'exception' => $e,
					]);
				}
			}

			usort($teams, static function (array $a, array $b): int {
				return strcasecmp($a['displayName'], $b['displayName']);
			});

			return new DataResponse(['teams' => $teams]);
		} catch (\Throwable $e) {
			$this->logger->warning('Failed to list teams: ' . $e->getMessage(), [
				'exception' => $e,
			]);
			return new DataResponse(['teams' => []], 200);
		}
	}

	/**
	 * @AdminRequired
	 * Get rate limit status (admin-only)
	 */
	public function rateLimitStatus(): DataResponse {
		try {
			$status = $this->rateLimitService->getStatus();
			return new DataResponse($status);
		} catch (Exception $e) {
			$this->logger->error('Failed to get rate limit status: ' . $e->getMessage());
			return new DataResponse(['error' => $e->getMessage()], 500);
		}
	}

	/**
	 * @AdminRequired
	 * Manually process queued requests (admin-only)
	 */
	public function processQueue(): DataResponse {
		try {
			if (!$this->rateLimitService->isEnabled()) {
				return new DataResponse([
					'success' => false,
					'error' => 'Rate limiting is not enabled',
				], 400);
			}

			$stats = $this->rateLimitService->getQueueStats();
			if ($stats['pending'] === 0) {
				return new DataResponse([
					'success' => true,
					'processed' => 0,
					'message' => 'No pending requests in queue',
				]);
			}

			// Process up to 10 requests
			$maxToProcess = min(10, $stats['pending']);
			$processedCount = 0;
			$errors = [];

			for ($i = 0; $i < $maxToProcess; $i++) {
				// Check if we have rate limit capacity
				if (!$this->rateLimitService->canProcess()) {
					break;
				}

				$request = $this->rateLimitService->getNextPending();
				if ($request === null) {
					break;
				}

				// Skip stale requests (older than 1 hour)
				if ($request->isStale(3600)) {
					$this->rateLimitService->markFailed($request, 'Request expired (too old)');
					continue;
				}

				// Process the request
				$result = $this->processQueuedRequest($request);
				if ($result['success']) {
					$processedCount++;
				} else {
					$errors[] = $result['error'];
				}

				// Small delay between requests
				usleep(100000); // 100ms
			}

			$remainingStats = $this->rateLimitService->getQueueStats();

			return new DataResponse([
				'success' => true,
				'processed' => $processedCount,
				'remaining' => $remainingStats['pending'],
				'errors' => $errors,
			]);
		} catch (Exception $e) {
			$this->logger->error('Failed to process queue: ' . $e->getMessage());
			return new DataResponse([
				'success' => false,
				'error' => $e->getMessage(),
			], 500);
		}
	}

	/**
	 * Process a single queued request
	 * 
	 * @return array{success: bool, error?: string}
	 */
	private function processQueuedRequest(QueuedRequest $request): array {
		$this->rateLimitService->markProcessing($request);
		$this->rateLimitService->recordUsage();

		try {
			$bot = $this->botMapper->findById($request->getBotId());
			
			if (!$bot->getIsActive()) {
				throw new Exception('Bot is no longer active');
			}

			$response = $this->botService->processMessage(
				$bot,
				$request->getMessage(),
				$request->getRoomToken(),
				$request->getUserId(),
				$request->getOriginalMessage(),
				null,
				true // isFromQueue
			);

			$this->rateLimitService->markCompleted($request, $response);

			$this->talkHandler->sendReplyToTalk(
				$request->getRoomToken(),
				$response,
				0
			);

			return ['success' => true];

		} catch (DoesNotExistException $e) {
			$this->rateLimitService->markFailed($request, 'Bot no longer exists');
			return ['success' => false, 'error' => 'Bot not found'];
		} catch (Exception $e) {
			if ($request->getAttempts() < 3) {
				$this->rateLimitService->markForRetry($request, $e->getMessage());
			} else {
				$this->rateLimitService->markFailed($request, 'Max retries exceeded: ' . $e->getMessage());
			}
			return ['success' => false, 'error' => $e->getMessage()];
		}
	}

	/**
	 * @AdminRequired
	 * Queue reindex for all embeddings (all bot RAG sources)
	 */
	public function reindexAllEmbeddings(): DataResponse {
		try {
			$sources = $this->botSourceMapper->findAll();
			$queuedRagSources = 0;
			foreach ($sources as $source) {
				$this->ragIngestionService->enqueueSource($source->getId(), true);
				$queuedRagSources++;
			}

			return new DataResponse([
				'success' => true,
				'queued_rag_sources' => $queuedRagSources,
				'message' => 'Reindex jobs queued. Processing happens via background jobs.',
			]);
		} catch (Exception $e) {
			$this->logger->error('Failed to queue global embedding reindex', [
				'exception' => $e,
			]);
			return new DataResponse([
				'success' => false,
				'error' => $e->getMessage(),
			], 500);
		}
	}

	/**
	 * @return array<string,mixed>
	 */
	private function buildSettingsPayload(Settings $settings): array {
		$data = $settings->jsonSerialize();
		$data['app_icon_upload_urls'] = [
			'black' => $this->urlGenerator->linkToRoute('educai.app_icon.upload', ['variant' => 'black']),
			'white' => $this->urlGenerator->linkToRoute('educai.app_icon.upload', ['variant' => 'white']),
		];
		$data['app_icon_preview_urls'] = [
			'black' => $this->urlGenerator->linkToRoute('educai.app_icon.preview', ['variant' => 'black']),
			'white' => $this->urlGenerator->linkToRoute('educai.app_icon.preview', ['variant' => 'white']),
		];
		$data['app_icon_runtime_urls'] = $this->appIconService->getRuntimeIconUrls();

		return $data;
	}

	/**
	 * @return array<string,mixed>
	 */
	private function extractRateLimitConfig(Settings $settings): array {
		return [
			'rate_limit_enabled' => (bool)$settings->getRateLimitEnabled(),
			'rate_limit_second' => $settings->getRateLimitSecond(),
			'rate_limit_minute' => $settings->getRateLimitMinute(),
			'rate_limit_hour' => $settings->getRateLimitHour(),
			'rate_limit_day' => $settings->getRateLimitDay(),
			'embedding_rate_limit_mode' => $settings->getEmbeddingRateLimitMode(),
			'embedding_rate_limit_second' => $settings->getEmbeddingRateLimitSecond(),
			'embedding_rate_limit_minute' => $settings->getEmbeddingRateLimitMinute(),
			'embedding_rate_limit_hour' => $settings->getEmbeddingRateLimitHour(),
			'embedding_rate_limit_day' => $settings->getEmbeddingRateLimitDay(),
		];
	}
}