🐛 Bug Report: Gemini API Integration Failing in Competitors Model

[ArnabMistry]

Description

The generateCompetitors function in backend/models/competitorsModel.js is failing due to several issues with the Gemini API integration. The primary issue appears to be an incorrect model version reference.

---

Current Behavior

• API calls to Gemini are failing
• Function throws errors when attempting to generate competitor analysis
• JSON parsing may fail intermittently

Expected Behavior

• Successfully connect to Gemini API
• Generate competitor analysis based on startup data
• Return properly formatted JSON response

Root Cause Analysis

1. Invalid Model Version (Critical)
   Issue: Using non-existent model gemini-2.5-flash

// ❌ Current (incorrect)
const MODEL_URL = 'https://generativelanguage.googleapis.com/v1/models/gemini-2.5-flash:generateContent';

// ✅ Should be
const MODEL_URL = 'https://generativelanguage.googleapis.com/v1/models/gemini-1.5-flash:generateContent';

2. Insufficient Error Handling (High)

• No validation for empty API responses
• JSON parsing lacks try-catch protection
• Could crash application on malformed responses

3. Response Validation Missing (Medium)

• No checks for required response structure
• Assumes AI always returns valid JSON format

Proposed Solution

const generateCompetitors = async (data) => {
  const prompt = `...`; // existing prompt

  try {
    const response = await axios.post(
      MODEL_URL + `?key=${GEMINI_API_KEY}`,
      {
        contents: [{ parts: [{ text: prompt }] }]
      },
      {
        headers: {
          'Content-Type': 'application/json'
        }
      }
    );

    let rawText = response.data.candidates?.[0]?.content?.parts?.[0]?.text;
    
    // Validate response exists
    if (!rawText) {
      throw new Error('Empty response from Gemini API');
    }

    // Clean markdown formatting
    rawText = rawText.replace(/```json|```/g, '').trim();
    
    if (!rawText) {
      throw new Error('No content after cleaning response');
    }

    // Safe JSON parsing
    try {
      const parsedData = JSON.parse(rawText);
      
      // Validate expected structure
      if (!parsedData.competitors || !Array.isArray(parsedData.competitors)) {
        throw new Error('Invalid response structure from Gemini');
      }
      
      return parsedData;
    } catch (parseError) {
      console.error('JSON parsing failed:', parseError.message);
      console.error('Raw response:', rawText);
      throw new Error('Failed to parse Gemini response as JSON');
    }

  } catch (error) {
    if (error.response) {
      console.error('Gemini API Error:', {
        status: error.response.status,
        statusText: error.response.statusText,
        data: error.response.data
      });
    } else {
      console.error('Gemini Competitors Model Error:', error.message);
    }
    throw new Error('Failed to generate competitors from Gemini');
  }
};

Additional Context

This issue was discovered during code review. The function is currently non-functional due to the incorrect model version, and even if that's fixed, the lack of proper error handling could cause application crashes.