/*
 * Copyright 2025 Google. This software is provided as-is, without warranty or representation for any use or purpose. 
 * Your use of it is subject to your agreement with Google.
 */

package com.example.service.base;

import com.example.exception.GeminiClientException;
import com.google.genai.Client;
import com.google.genai.errors.GenAiIOException;
import com.google.genai.types.Content;
import com.google.genai.types.GenerateContentConfig;
import com.google.genai.types.GenerateContentResponse;
import com.google.genai.types.Part;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Service;

/**
 * Service for interacting with the Gemini API to generate content.
 * It encapsulates the low-level API calls, handling prompt configuration,
 * and error management to provide a clean and robust content generation interface.
 */
@Service
public class GeminiClientService {

    private static final Logger logger = LoggerFactory.getLogger(GeminiClientService.class);
    private final Client geminiClient;

    public GeminiClientService(Client geminiClient) {
        this.geminiClient = geminiClient;
    }

    public String generateContent(String prompt, Float temperature, Integer maxOutputTokens, String modelName,Float topP) throws GeminiClientException {
        try {
            Content content = Content.fromParts(Part.fromText(prompt));
            GenerateContentConfig config = GenerateContentConfig.builder()
                    .temperature(temperature)
                    .maxOutputTokens(maxOutputTokens)
                    .topP(topP)
                    .build();
            
            logger.debug("Sending request to Gemini model '{}'", modelName);
            GenerateContentResponse response = geminiClient.models.generateContent(modelName, content, config);

            if (response != null && response.text() != null) {
                return response.text();
            } else {
                logger.warn("Gemini returned no content or an unexpected response structure for model '{}'.", modelName);
                throw new GeminiClientException("No content generated or unexpected response structure.");
            }
        } catch (GenAiIOException e) {
            logger.error("Gemini API I/O error while calling model '{}': {}", modelName, e.getMessage(), e);
            throw new GeminiClientException("An API communication issue occurred: " + e.getMessage(), e);
        } catch (Exception e) {
            logger.error("An unexpected error occurred during Gemini content generation for model '{}': {}", modelName, e.getMessage(), e);
            throw new GeminiClientException("An unexpected issue occurred during content generation.", e);
        }
    }
}