<?php

namespace Controller\Api;

use Framework\Controller;
use Infrastructure\AI\AIConfig;
use Infrastructure\AI\ChatService;
use Infrastructure\AI\OllamaService;
use Infrastructure\AI\QdrantService;

class ChatController extends Controller
{
    private ChatService $chatService;
    private OllamaService $ollamaService;
    private QdrantService $qdrantService;

    public function __construct()
    {
        $config = AIConfig::fromCredentialsFile();
        $this->chatService = $config->createChatService();
        $this->ollamaService = $config->createOllamaService();
        $this->qdrantService = $config->createQdrantService();
    }

    /**
     * POST /api/v1/chat
     * Handle chat message
     */
    public function send(): void
    {
        $input = json_decode(file_get_contents('php://input'), true);
        $question = trim($input['message'] ?? '');

        if ($question === '') {
            $this->json(['error' => 'Keine Frage angegeben'], 400);

            return;
        }

        try {
            $result = $this->askChat($question);
            $this->json($result);
        } catch (\Exception $e) {
            $this->json(['error' => $e->getMessage()], 500);
        }
    }

    /**
     * GET /api/v1/chat/search
     * Search for relevant chunks
     */
    public function search(): void
    {
        $query = trim($_GET['q'] ?? '');
        $limit = (int) ($_GET['limit'] ?? 5);

        if ($query === '') {
            $this->json(['error' => 'Keine Suchanfrage'], 400);

            return;
        }

        try {
            $results = $this->searchChunks($query, $limit);
            $this->json(['results' => $results]);
        } catch (\Exception $e) {
            $this->json(['error' => $e->getMessage()], 500);
        }
    }

    /**
     * GET /api/v1/chat/stats
     * Get chat/document statistics (Doc2Vector Pipeline)
     */
    public function stats(): void
    {
        try {
            $pdo = $this->getDatabase();

            $stats = [
                'dokumente' => (int) $pdo->query('SELECT COUNT(*) FROM dokumentation WHERE depth = 0')->fetchColumn(),
                'seiten' => (int) $pdo->query('SELECT COUNT(*) FROM dokumentation WHERE depth > 0')->fetchColumn(),
                'chunks' => (int) $pdo->query('SELECT COUNT(*) FROM dokumentation_chunks')->fetchColumn(),
                'tokens' => (int) $pdo->query('SELECT COALESCE(SUM(token_count), 0) FROM dokumentation_chunks')->fetchColumn(),
                'analyzed' => (int) $pdo->query("SELECT COUNT(*) FROM dokumentation_chunks WHERE analysis_status = 'completed'")->fetchColumn(),
                'synced' => (int) $pdo->query('SELECT COUNT(*) FROM dokumentation_chunks WHERE qdrant_id IS NOT NULL')->fetchColumn(),
            ];

            $this->json($stats);
        } catch (\Exception $e) {
            $this->json(['error' => $e->getMessage()], 500);
        }
    }

    /**
     * Ask chat question using ChatService
     *
     * @param string $question User's question
     *
     * @return array<string, mixed> Chat response with answer and sources
     *
     * @throws \RuntimeException If chat service fails
     */
    private function askChat(string $question): array
    {
        try {
            // Use dokumentation_chunks collection for RAG
            return $this->chatService->chat($question, 'claude-opus-4-5-20251101', 'dokumentation_chunks', 5);
        } catch (\RuntimeException $e) {
            throw new \RuntimeException('Chat-Service konnte nicht ausgeführt werden: ' . $e->getMessage(), 0, $e);
        }
    }

    /**
     * Search for similar chunks using vector search
     *
     * @param string $query Search query
     * @param int    $limit Maximum number of results
     *
     * @return array<int, array{id: int|string, score: float, payload: array<string, mixed>}> Search results
     *
     * @throws \RuntimeException If search fails
     */
    private function searchChunks(string $query, int $limit): array
    {
        try {
            $queryEmbedding = $this->ollamaService->getEmbedding($query);

            // Use dokumentation_chunks collection
            return $this->qdrantService->search($queryEmbedding, 'dokumentation_chunks', $limit);
        } catch (\RuntimeException $e) {
            throw new \RuntimeException('Suche konnte nicht ausgeführt werden: ' . $e->getMessage(), 0, $e);
        }
    }

    /**
     * Get database connection for dokumentation tables (ki_dev)
     */
    private function getDatabase(): \PDO
    {
        return \Infrastructure\Config\DatabaseFactory::dev();
    }
}