package com.homme.demo.service;

import java.time.LocalDate;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.stereotype.Service;

import com.homme.demo.entity.Document;
import com.homme.demo.entity.DocumentChunck;
import com.homme.demo.repository.DocumentChunckRepository;
import com.homme.demo.repository.DocumentRepository;


import jakarta.transaction.Transactional;

@Service
public class DocumentStorageService {
	
	@Autowired
	private DocumentRepository documentRepossitory;
	
	@Autowired
	private DocumentChunckRepository documentChunckRepository;
	
	@Autowired
	private DocumentChunckService documentChunkService;
	
	@Autowired
	private AzureEmbeddingService azureEmbeddingService;
	
	
	
	@Transactional
	public ResponseEntity<String> saveDocuemntWithChuncks(
			String sourceUrl,
			String rawText,
			String cleanText) {
		
		String message = "";
		if(documentRepossitory.existsBySourceUrl(sourceUrl)) {
			
			message = "Dieses Dokument wurde bereits gespeichert.";
			return new ResponseEntity<>(message,
										HttpStatus.CONFLICT);
		}
			
		Document document = Document.builder()
				.sourceUrl(sourceUrl)
				.rawText(rawText)
				.cleanText(cleanText)
				.createdAt(LocalDate.now())
				.build();
		Integer savedDocumentId = documentRepossitory.save(document).getId();
		
		
		
		ExecutorService pool = Executors.newFixedThreadPool(4);
		try
		{
	
			List<String> chuncks = documentChunkService.splitTextIntoChunks(cleanText);
			
			List<Future<float[]>> futures = new ArrayList<>();
			
			for(int i = 0; i < chuncks.size(); i++) {
				
				String chunckText = chuncks.get(i);
				
				futures.add(pool.submit(() ->
				      (chunckText == null || chunckText.isBlank())
				      ?null
				      : azureEmbeddingService.createEmbeddingFloatArray(chunckText, "document")
				      ));
				
			    }
				for(int i=0; i < chuncks.size(); i++) {
					
					
					float [] embedding = futures.get(i).get();
					String chunckText = chuncks.get(i);
					DocumentChunck documentChunck = DocumentChunck.builder()
							.chunckIndex(i)
							.chunckText(chunckText)
							.documentId(savedDocumentId)
							.embedding(embedding)
							.build();
					documentChunckRepository.save(documentChunck);
					
				
				}
				message = "Dokument wurde erfolgreich gespeichert.";
				return new ResponseEntity<>(message,
						HttpStatus.CREATED);
		
		     }catch(InterruptedException | ExecutionException e) {
			
					Thread.currentThread().interrupt();
					message = "Fehler bei parallerer Verarbeitung"+ e.getMessage();
					return new ResponseEntity<>(message, HttpStatus.BAD_REQUEST);
			
		} finally {
			pool.shutdown();
		}
	}
		
	@Transactional
	public int fillMissingEmbedding() {
		
		
		List<DocumentChunck> chuncks = documentChunckRepository.findByEmbeddingIsNull();
		
		
		
		ExecutorService pool = Executors.newFixedThreadPool(6);
		
		List<Future<float[]>> futures = new ArrayList<>();
		
		try {
		
			for(DocumentChunck chunck: chuncks) {
				
				String chunckText = chunck.getChunckText();
				
				futures.add(pool.submit(() -> 
				     (chunckText == null || chunckText.isBlank())
				     ? null
				     : azureEmbeddingService.createEmbeddingFloatArray(chunckText)
				     ));
				   
				
			}
			int updatedCount = 0;
			for( int i = 0; i < chuncks.size(); i++) {
				float[] embedding = futures.get(i).get();
				chuncks.get(i).setEmbedding(embedding);
				documentChunckRepository.save(chuncks.get(i));
				updatedCount++;
				System.out.println("updatedCount  = "+updatedCount);
				
			}
			return updatedCount;
			
		}catch(InterruptedException | ExecutionException e ) {
			Thread.currentThread().interrupt();
			throw new RuntimeException("Fehler bei parallerer Verarbeitung: "+e.getMessage());
			
		}finally {
			pool.shutdown();
		}
		
		
		
	}
	

}