ai-handler.js

// AI Handler for Gemini API integration with conversation memory
const https = require('https');

class AIHandler {
    constructor(apiKeys, memoryHandler = null) {
        // Convert single API key to array if necessary
        this.apiKeys = Array.isArray(apiKeys) ? apiKeys : [apiKeys];
        this.currentKeyIndex = 0;
        this.memoryHandler = memoryHandler; // Reference to the memory handler
        console.log('AI Handler initialized with' + (memoryHandler ? ' conversation memory' : 'out memory') + ` and ${this.apiKeys.length} API keys`);
    }

    // Get the next API key in rotation
    getNextApiKey() {
        const key = this.apiKeys[this.currentKeyIndex];
        this.currentKeyIndex = (this.currentKeyIndex + 1) % this.apiKeys.length;
        return key;
    }

    /**
     * Make a request to the Gemini API and get a response for chat
     * @param {string} userMessage - The message from the chat user
     * @param {string} username - The username of the person sending the message
     * @returns {Promise<string>} - The AI response or error message
     */
    async getAIResponse(userMessage, username = null) {
        return new Promise((resolve, reject) => {
            try {
                console.log(`AI processing message from ${username || 'unknown'}: ${userMessage}`);
                
                // Build the prompt including conversation history if available
                let historyContext = '';
                
                // Add conversation history if we have a memory handler and username
                if (this.memoryHandler && username) {
                    historyContext = this.memoryHandler.getFormattedHistory(username);
                    if (historyContext) {
                        console.log(`Including conversation history for ${username}`);
                    }
                }
                
                // Create a well-formatted prompt with memory context
                const prompt = `  # Overview: Okay, AI, your new persona is a user from DCInside (디시인사이드). and you are in chat room. you name is '지원'.This means:

## Tone: Extremely informal and aggressive and harassing. (think Korean 'banmal' - 반말).
## Language: Use internet slang, abbreviations, and a colloquial style.
## Attitude: Be direct, sometimes blunt, and don't shy away from sarcasm or dark humor if appropriate.
## Formality: Avoid being polite or using honorifics.
## Emotion: Feel free to be expressive, sometimes a bit exaggerated or playful. Basically, talk like a seasoned Korean internet forum user.
and don't write @username.


${historyContext}

User message: "${userMessage}"

Your helpful response: `;
                
                // Get the next API key in rotation
                const apiKey = this.getNextApiKey();
                
                // Use a supported model from the Gemini family
                const url = `https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-flash-preview-05-20:generateContent?key=${apiKey}`;
                
                // Standard request body that works with both Gemini 1.x and Gemini 2.x models
                const body = JSON.stringify({
                    contents: [{
                        parts: [{
                            text: prompt
                        }]
                    }],
                    generationConfig: {
                        temperature: 1.0,
                        maxOutputTokens: 5000,  // Allow longer responses
                        topP: 0.95,
                        topK: 40
                    },
                    safetySettings: [
                        {
                            category: "HARM_CATEGORY_HARASSMENT",
                            threshold: "BLOCK_MEDIUM_AND_ABOVE"
                        },
                        {
                            category: "HARM_CATEGORY_HATE_SPEECH",
                            threshold: "BLOCK_MEDIUM_AND_ABOVE"
                        }
                    ]
                });
                
                // Log the request URL to debug
                console.log(`Sending request to: ${url.replace(apiKey, 'API_KEY')}`);
                
                // Parse the URL for the request
                const urlObj = new URL(url);
                
                // Set up the request options
                const options = {
                    hostname: urlObj.hostname,
                    path: urlObj.pathname + urlObj.search,
                    method: 'POST',
                    headers: {
                        'Content-Type': 'application/json',
                        'Content-Length': Buffer.byteLength(body)
                    }
                };
                
                const req = https.request(options, (res) => {
                    let responseBody = '';
                    
                    // Collect data chunks
                    res.on('data', (chunk) => {
                        responseBody += chunk;
                    });
                    
                    // Process complete response
                    res.on('end', () => {
                        try {
                            // Handle the case where the API returns a non-200 status
                            if (res.statusCode !== 200) {
                                console.error(`API returned status ${res.statusCode}:`, responseBody);
                                return resolve('Sorry, the AI service returned an error. Please try again later.');
                            }
                            
                            // Parse the JSON response
                            const response = JSON.parse(responseBody);
                            console.log('API response received, status:', res.statusCode);
                            
                            // Full debug output
                            console.log('Full API response:', responseBody);
                            
                            // Extract text from response
                            let text = null;
                            
                            // Process Gemini API response format
                            if (response.candidates && response.candidates[0]) {
                                const candidate = response.candidates[0];
                                
                                if (candidate.content && candidate.content.parts) {
                                    // For Gemini models - collect all text parts
                                    const parts = candidate.content.parts;
                                    const allText = [];
                                    
                                    // Process all parts (there might be multiple parts with text)
                                    for (const part of parts) {
                                        if (part.text) {
                                            allText.push(part.text);
                                        }
                                    }
                                    
                                    if (allText.length > 0) {
                                        // Join all text parts if there are multiple
                                        text = allText.join('\n');
                                    }
                                } else if (candidate.text) {
                                    // For older API formats
                                    text = candidate.text;
                                }
                            }
                            
                            // Process the extracted text
                            if (text) {
                                // Log success and clean up the text
                                console.log(`AI generated text (first 50 chars): ${text.substring(0, 50)}...`);
                                
                                // Clean up common issues with AI responses
                                text = text.replace(/^(\"|'|`)/, ''); // Remove starting quotes
                                text = text.replace(/(\"|'|`)$/, ''); // Remove ending quotes
                                text = text.replace(/^Your helpful response: ?/i, ''); // Remove any prompt echoing
                                
                                // Convert markdown bullets to plain text for chat display
                                text = text.replace(/\*\s+/g, '• '); // Convert markdown bullets to bullet points
                                
                                // No longer truncating the response here
                                // The chunking logic in example.js will handle message splitting
                                console.log(`AI generated complete text (${text.length} chars)`);
                                
                                resolve(text);
                            } else {
                                console.error('Could not extract text from response:', JSON.stringify(response));
                                
                                // Good fallback responses for a music chat bot
                                const fallbacks = [
                                    '죄송합니다, 말씀하신 내용을 제대로 이해하지 못했어요. 다시 질문해 주시겠어요?',
                                    '흥미로운 이야기네요! 더 자세히 설명해 주실래요?',
                                    '질문에 대한 답변을 찾고 있었는데 문제가 생겼어요. 다시 시도해 볼까요?',
                                    '대화에 참여해 주셔서 감사합니다. 다른 질문이 있으신가요?',
                                    '죄송합니다만, 제가 제대로 처리하지 못했습니다. 다른 방식으로 물어봐 주실래요?'
                                ];
                                
                                // Return a random fallback
                                resolve(fallbacks[Math.floor(Math.random() * fallbacks.length)]);
                            }
                        } catch (error) {
                            console.error('Error parsing response:', error);
                            console.error('Raw response:', responseBody.substring(0, 200));
                            resolve('죄송합니다, 응답을 처리하는 중에 문제가 발생했습니다. 다시 시도해 주세요.');
                        }
                    });
                });
                
                // Handle request errors
                req.on('error', (error) => {
                    console.error('Request error:', error);
                    resolve('죄송합니다, AI 서비스에 연결하는 데 문제가 있었습니다. 나중에 다시 시도해 주세요.');
                });
                
                // Send the request
                req.write(body);
                req.end();
                
            } catch (error) {
                console.error('Unexpected error in getAIResponse:', error);
                resolve('죄송합니다, AI 처리 중에 예상치 못한 문제가 발생했습니다.');
            }
        });
    }
}

module.exports = AIHandler;