Update backend/server.js

backend/server.js

@@ -1,667 +1,340 @@
-const express = require('express');
-const cors = require('cors');
-const multer = require('multer');
-const path = require('path');
-const fs = require('fs');
-const { spawn } = require('child_process');
-const sqlite3 = require('sqlite3').verbose();
-const sharp = require('sharp');
-const { v4: uuidv4 } = require('uuid');
-require('dotenv').config();
-
-const app = express();
-// cPanel and other hosts use the PORT environment variable
-const PORT = process.env.PORT || 5000;
-
-// --- Middleware ---
-// Enable CORS for all routes
-app.use(cors());
-// Parse JSON bodies for API requests
-app.use(express.json());
-app.use('/uploads', express.static(path.join(__dirname, 'uploads')));
-
-// Ensure directories exist
-const dirs = ['uploads', 'temp', 'results', 'database'];
-dirs.forEach(dir => {
-    const dirPath = path.join(__dirname, dir);
-    if (!fs.existsSync(dirPath)) {
-        fs.mkdirSync(dirPath, { recursive: true });
-    }
-});
-
-// --- DATABASE SETUP ---
-const dbPath = path.join(__dirname, 'database', 'water_quality.db');
-const db = new sqlite3.Database(dbPath, (err) => {
-    if (err) {
-        console.error('Error opening database', err.message);
-    } else {
-        console.log(`Connected to the SQLite database at ${dbPath}`);
-    }
-});
-db.serialize(() => {
-    db.run(`CREATE TABLE IF NOT EXISTS water_tests (
-      id TEXT PRIMARY KEY,
-      timestamp DATETIME DEFAULT CURRENT_TIMESTAMP,
-      user_id TEXT,
-      latitude REAL,
-      longitude REAL,
-      water_source TEXT,
-      image_path TEXT,
-      ph REAL,
-      chlorine REAL,
-      nitrates REAL,
-      hardness REAL,
-      alkalinity REAL,
-      bacteria INTEGER,
-      overall_quality TEXT,
-      safety_level TEXT,
-      confidence REAL,
-      processing_time REAL,
-      alerts TEXT,
-      color_analysis TEXT
-    )`);
-
-    db.run(`CREATE TABLE IF NOT EXISTS water_alerts (
-      id TEXT PRIMARY KEY,
-      test_id TEXT,
-      alert_type TEXT,
-      severity TEXT,
-      message TEXT,
-      timestamp DATETIME DEFAULT CURRENT_TIMESTAMP,
-      latitude REAL,
-      longitude REAL,
-      FOREIGN KEY(test_id) REFERENCES water_tests(id)
-    )`);
-
-    db.run(`CREATE TABLE IF NOT EXISTS calibration_data (
-      id TEXT PRIMARY KEY,
-      parameter TEXT,
-      color_value TEXT,
-      actual_value REAL,
-      timestamp DATETIME DEFAULT CURRENT_TIMESTAMP
-    )`);
-});
-
-
-// --- MULTER CONFIG FOR IMAGE UPLOADS ---
-const imageStorage = multer.diskStorage({
-    destination: (req, file, cb) => {
-        cb(null, path.join(__dirname, 'uploads/'));
-    },
-    filename: (req, file, cb) => {
-        const uniqueName = `${Date.now()}-${Math.round(Math.random() * 1E9)}${path.extname(file.originalname)}`;
-        cb(null, uniqueName);
-    }
-});
-
-const imageUpload = multer({
-    storage: imageStorage,
-    limits: { fileSize: 10 * 1024 * 1024 }, // 10MB limit
-    fileFilter: (req, file, cb) => {
-        if (file.mimetype.startsWith('image/')) {
-            cb(null, true);
-        } else {
-            cb(new Error('Only image files are allowed!'), false);
-        }
-    }
-});
-
-// --- MULTER CONFIG FOR AUDIO UPLOADS ---
-const audioStorage = multer.diskStorage({
-    destination: function (req, file, cb) {
-        cb(null, path.join(__dirname, 'temp/')); // Save audio files in a temp directory
-    },
-    filename: function (req, file, cb) {
-        const uniqueSuffix = Date.now() + '-' + Math.round(Math.random() * 1E9);
-        cb(null, 'audio-' + uniqueSuffix + path.extname(file.originalname));
-    }
-});
-
-const audioUpload = multer({
-    storage: audioStorage,
-    limits: { fileSize: 25 * 1024 * 1024 }, // 25MB limit for audio
-    fileFilter: (req, file, cb) => {
-        if (file.mimetype.startsWith('audio/')) {
-            cb(null, true);
-        } else {
-            cb(new Error('Only audio files are allowed!'), false);
-        }
-    }
-});
-
-// --- MULTER CONFIG FOR DNA SEQUENCE FILES ---
-const dnaFileStorage = multer.diskStorage({
-    destination: function (req, file, cb) {
-        cb(null, path.join(__dirname, 'temp/')); // Save DNA files in the same temp directory
-    },
-    filename: function (req, file, cb) {
-        const uniqueSuffix = Date.now() + '-' + Math.round(Math.random() * 1E9);
-        cb(null, 'dna-' + uniqueSuffix + path.extname(file.originalname));
-    }
-});
-
-const dnaUpload = multer({
-    storage: dnaFileStorage,
-    limits: { fileSize: 50 * 1024 * 1024 }, // 50MB limit for sequence files
-    fileFilter: (req, file, cb) => {
-        // Loosely accept text-based formats common for DNA
-        const allowedTypes = ['.fasta', '.fastq', '.txt', '.fa', '.fq'];
-        if (allowedTypes.includes(path.extname(file.originalname).toLowerCase())) {
-            cb(null, true);
-        } else {
-            cb(new Error('Invalid file type for DNA analysis!'), false);
-        }
-    }
-});
-
-// --- HELPER FUNCTIONS ---
-
-function fallbackAnalysis(imagePath, waterSource) {
-    console.log('--- Executing Node.js Fallback Analysis ---');
-    // This simulates the Python script's output when it's not available.
-    return {
-        ph: 7.1,
-        chlorine: 0.5,
-        nitrates: 5,
-        hardness: 150,
-        alkalinity: 120,
-        bacteria: 0,
-        confidence: 40, // Lower confidence to indicate it's a fallback
-        processingMethod: "Node.js Fallback"
-    };
-}
-
-function callPythonAnalysis(imagePath, waterSource) {
-    return new Promise((resolve, reject) => {
-        const scriptPath = path.join(__dirname, 'python', 'water_analysis.py');
-        const pythonProcess = spawn('python', [scriptPath, imagePath, waterSource || 'unknown']);
-
-        let dataString = '';
-        let errorString = '';
-
-        pythonProcess.stdout.on('data', (data) => {
-            dataString += data.toString();
-        });
-
-        pythonProcess.stderr.on('data', (data) => {
-            errorString += data.toString();
-        });
-
-        pythonProcess.on('close', (code) => {
-            if (code === 0) {
-                try {
-                    const result = JSON.parse(dataString);
-                    resolve(result);
-                } catch (error) {
-                    reject(new Error('Failed to parse Python output'));
-                }
-            } else {
-                console.log(`Python script at ${scriptPath} not available or failed, using fallback. Error: ${errorString}`);
-                resolve(fallbackAnalysis(imagePath, waterSource));
-            }
-        });
-    });
-}
-
-// Dummy C++ preprocessor call for demonstration
-async function callCppPreprocessing(imagePath) {
-    return new Promise((resolve, reject) => {
-        // In a real scenario, you would spawn a C++ executable.
-        // For this demo, we'll just simulate a failure to show the fallback.
-        reject(new Error("C++ preprocessor not found or failed."));
-    });
-}
-
-// --- API ROUTES ---
-
-// --- BIODIVERSITYEAR AUDIO ANALYSIS ENDPOINT ---
-app.post('/api/analyze-audio', audioUpload.single('audioFile'), (req, res) => {
-    console.log('✅ Backend: Received audio file analysis request.');
-
-    if (!req.file || req.file.size === 0) {
-        if (req.file) {
-            fs.unlink(req.file.path, (err) => {
-                if (err) console.error(`- Error deleting empty file: ${err.message}`);
-            });
-        }
-        return res.status(400).json({ message: 'The provided audio file is empty or missing. Please record for at least one second.' });
-    }
-
-    console.log(`- Audio file saved to: ${req.file.path}`);
-    console.log(`- Region: ${req.body.region}, Habitat: ${req.body.habitat}`);
-    console.log('▶️ Calling Python AI script for audio analysis...');
-
-    const pythonProcess = spawn('python', [
-        path.join(__dirname, 'python', 'audio_analyzer.py'),
-        req.file.path
-    ]);
-
-    let analysisResult = '';
-    let errorOutput = '';
-
-    pythonProcess.stdout.on('data', (data) => {
-        analysisResult += data.toString();
-    });
-
-    pythonProcess.stderr.on('data', (data) => {
-        errorOutput += data.toString();
-    });
-
-    pythonProcess.on('close', (code) => {
-        // Clean up the uploaded audio file after analysis
-        fs.unlink(req.file.path, (err) => {
-            if (err) console.error(`- Error deleting temp audio file: ${err.message}`);
-            else console.log(`- Temporary audio file ${req.file.path} deleted.`);
-        });
-
-        if (code === 0) {
-            console.log('✅ Backend: Python audio script finished successfully.');
-            try {
-                const jsonData = JSON.parse(analysisResult);
-                res.status(200).json(jsonData);
-            } catch (e) {
-                console.error('❌ Backend: Error parsing JSON from Python audio script.', e);
-                res.status(500).json({ message: 'Failed to parse audio analysis result.' });
-            }
-        } else {
-            console.error(`❌ Backend: Python audio script exited with error code ${code}.`);
-            console.error(`- Python Error: ${errorOutput}`);
-            res.status(500).json({ message: 'Error during audio analysis.', error: errorOutput });
-        }
-    });
-});
-
-// --- BIO-STREAM AI DNA ANALYSIS ENDPOINT ---
-app.post('/api/analyze-dna', dnaUpload.single('dnaFile'), (req, res) => {
-    console.log('✅ Backend: Received DNA file analysis request for Bio-Stream AI.');
-
-    if (!req.file) {
-        return res.status(400).json({ message: 'No DNA file was uploaded.' });
-    }
-
-    console.log(`- DNA file saved to: ${req.file.path}`);
-    console.log('▶️ Calling Python AI script for DNA analysis...');
-
-    const pythonProcess = spawn('python', [
-        path.join(__dirname, 'python', 'dna_analyzer.py'),
-        req.file.path // Pass the full path of the uploaded file to the script
-    ]);
-
-    let analysisResult = '';
-    let errorOutput = '';
-
-    pythonProcess.stdout.on('data', (data) => {
-        analysisResult += data.toString();
-    });
-
-    pythonProcess.stderr.on('data', (data) => {
-        errorOutput += data.toString();
-    });
-
-    pythonProcess.on('close', (code) => {
-        // IMPORTANT: Clean up the uploaded DNA file after analysis is complete
-        fs.unlink(req.file.path, (err) => {
-            if (err) console.error(`- Error deleting temp DNA file: ${err.message}`);
-            else console.log(`- Temporary DNA file ${req.file.path} deleted.`);
-        });
-
-        if (code === 0) {
-            console.log('✅ Backend: Python DNA analysis script finished successfully.');
-            try {
-                const jsonData = JSON.parse(analysisResult);
-                res.status(200).json(jsonData);
-            } catch (e) {
-                console.error('❌ Backend: Error parsing JSON from Python DNA script.', e);
-                res.status(500).json({ message: 'Failed to parse DNA analysis result.' });
-            }
-        } else {
-            console.error(`❌ Backend: Python DNA script exited with error code ${code}.`);
-            console.error(`- Python Error: ${errorOutput}`);
-            res.status(500).json({ message: 'Error during DNA analysis.', error: errorOutput });
-        }
-    });
-});
-
-// --- PHANTOM FOOTPRINT ANALYSIS ENDPOINT ---
-app.post('/api/analyze-footprint', (req, res) => {
-    const { url } = req.body;
-    console.log(`✅ Backend: Received Phantom Footprint analysis request for URL: ${url}`);
-
-    if (!url) {
-        return res.status(400).json({ message: 'Product URL is required.' });
-    }
-
-    const pythonProcess = spawn('python', [
-        path.join(__dirname, 'python', 'phantom_footprint_analyzer.py')
-    ]);
-
-    let analysisResult = '';
-    let errorOutput = '';
-
-    pythonProcess.stdin.write(JSON.stringify({ url: url }));
-    pythonProcess.stdin.end();
-
-    pythonProcess.stdout.on('data', (data) => {
-        analysisResult += data.toString();
-    });
-
-    pythonProcess.stderr.on('data', (data) => {
-        errorOutput += data.toString();
-    });
-
-    pythonProcess.on('close', (code) => {
-        if (code === 0) {
-            console.log('✅ Backend: Python footprint script finished successfully.');
-            try {
-                const jsonData = JSON.parse(analysisResult);
-                res.status(200).json(jsonData);
-            } catch (e) {
-                console.error('❌ Backend: Error parsing JSON from Python script.', e);
-                res.status(500).json({ message: 'Failed to parse analysis result.' });
-            }
-        } else {
-            console.error(`❌ Backend: Python footprint script exited with error code ${code}.`);
-            console.error(`- Python Error: ${errorOutput}`);
-            res.status(500).json({ message: 'Error during footprint analysis.', error: errorOutput });
-        }
-    });
-});
-
-// --- E-WASTE ANALYSIS ENDPOINT ---
-app.post('/api/analyze-ewaste', (req, res) => {
-    console.log('✅ Backend: Received e-waste form analysis request.');
-
-    const pythonProcess = spawn('python', [
-        path.join(__dirname, 'python', 'ewaste_analyzer.py')
-    ]);
-
-    let analysisResult = '';
-    let errorOutput = '';
-
-    pythonProcess.stdin.write(JSON.stringify(req.body));
-    pythonProcess.stdin.end();
-
-    pythonProcess.stdout.on('data', (data) => {
-        analysisResult += data.toString();
-    });
-
-    pythonProcess.stderr.on('data', (data) => {
-        errorOutput += data.toString();
-    });
-
-    pythonProcess.on('close', (code) => {
-        if (code === 0) {
-            console.log('✅ Backend: Python e-waste script finished successfully.');
-            try {
-                const jsonData = JSON.parse(analysisResult);
-                res.status(200).json(jsonData);
-            } catch (e) {
-                console.error('❌ Backend: Error parsing JSON from Python script.', e);
-                res.status(500).json({ message: 'Failed to parse e-waste analysis result.' });
-            }
-        } else {
-            console.error(`❌ Backend: Python e-waste script exited with error code ${code}.`);
-            console.error(`- Python Error: ${errorOutput}`);
-            res.status(500).json({ message: 'Error during e-waste analysis.', error: errorOutput });
-        }
-    });
-});
-
-// --- AQUALENS WATER ANALYSIS ENDPOINT ---
-app.post('/api/analyze-water', imageUpload.single('image'), async (req, res) => {
-    const startTime = Date.now();
-
-    try {
-        if (!req.file) {
-            return res.status(400).json({ error: 'No image file provided' });
-        }
-
-        const { waterSource, latitude, longitude, userId } = req.body;
-        const imagePath = req.file.path;
-        const testId = uuidv4();
-
-        console.log(`🧪 Starting water analysis for test ${testId}`);
-        console.log(`📍 Location: ${latitude}, ${longitude}`);
-        console.log(`🚰 Water Source: ${waterSource}`);
-
-        // Step 1: Image preprocessing with Sharp (Node.js)
-        const preprocessedPath = path.join(__dirname, 'temp', `preprocessed_${testId}.jpg`);
-        await sharp(imagePath)
-            .resize(800, 600, { fit: 'inside' })
-            .normalize()
-            .sharpen()
-            .jpeg({ quality: 95 })
-            .toFile(preprocessedPath);
-
-        console.log('✅ Image preprocessing completed');
-
-        // Step 2: Advanced preprocessing with C++ (if available)
-        let processedImagePath = preprocessedPath;
-        try {
-            processedImagePath = await callCppPreprocessing(preprocessedPath);
-            console.log('✅ C++ preprocessing completed');
-        } catch (error) {
-            console.log('⚠️ C++ preprocessing not available, using Sharp preprocessing');
-        }
-
-        // Step 3: AI analysis with Python
-        const analysisResult = await callPythonAnalysis(processedImagePath, waterSource);
-        console.log('✅ AI analysis completed');
-
-        const processingTime = (Date.now() - startTime) / 1000;
-
-        // Step 4: Determine overall quality and safety
-        const { ph, chlorine, nitrates, hardness, alkalinity, bacteria } = analysisResult;
-
-        let overallQuality = 'Excellent';
-        let safetyLevel = 'Safe';
-        let alerts = [];
-        let recommendations = [];
-
-        if (ph < 6.5 || ph > 8.5) {
-            alerts.push(`pH levels outside safe range: ${ph.toFixed(1)}`);
-            recommendations.push('Consider pH adjustment or filtration system');
-            if (ph < 5.0 || ph > 9.5) {
-                safetyLevel = 'Unsafe';
-                overallQuality = 'Poor';
-                recommendations.push('Contact water authority immediately - pH outside safe drinking range');
-            } else {
-                overallQuality = 'Good';
-            }
-        }
-
-        if (chlorine > 4.0) {
-            alerts.push(`High chlorine levels: ${chlorine.toFixed(1)} ppm`);
-            recommendations.push('Let water sit uncovered for 30 minutes before drinking');
-            safetyLevel = 'Unsafe';
-            overallQuality = 'Poor';
-        } else if (chlorine < 0.2 && waterSource === 'Tap Water') {
-            alerts.push('Low chlorine in tap water may indicate contamination risk');
-            recommendations.push('Consider boiling water or using filtration');
-        }
-
-        if (nitrates > 10) {
-            alerts.push(`Elevated nitrate levels: ${nitrates} ppm`);
-            recommendations.push('Consider reverse osmosis filtration or alternative water source');
-            if (nitrates > 50) {
-                safetyLevel = 'Unsafe';
-                overallQuality = 'Poor';
-                recommendations.push('DO NOT DRINK - Especially dangerous for infants and pregnant women');
-            } else {
-                overallQuality = 'Fair';
-            }
-        }
-
-        if (bacteria > 0) {
-            alerts.push('Bacterial contamination detected');
-            recommendations.push('Boil water for 1 minute before drinking or use alternative source');
-            safetyLevel = 'Unsafe';
-            overallQuality = 'Poor';
-        }
-
-        if (hardness > 180) {
-            alerts.push(`Very hard water: ${hardness} ppm`);
-            recommendations.push('Consider water softener to protect plumbing and improve taste');
-            if (overallQuality === 'Excellent') overallQuality = 'Good';
-        }
-
-        // Step 5: Save to database
-        const dbData = {
-            id: testId,
-            user_id: userId || null,
-            latitude: parseFloat(latitude) || null,
-            longitude: parseFloat(longitude) || null,
-            water_source: waterSource || 'Unknown',
-            image_path: imagePath,
-            ph: ph,
-            chlorine: chlorine,
-            nitrates: nitrates,
-            hardness: hardness,
-            alkalinity: alkalinity,
-            bacteria: bacteria,
-            overall_quality: overallQuality,
-            safety_level: safetyLevel,
-            confidence: analysisResult.confidence || 95,
-            processing_time: processingTime,
-            alerts: JSON.stringify(alerts),
-            color_analysis: JSON.stringify(analysisResult.colorChannels || {})
-        };
-
-        db.run(`INSERT INTO water_tests (
-        id, user_id, latitude, longitude, water_source, image_path,
-        ph, chlorine, nitrates, hardness, alkalinity, bacteria,
-        overall_quality, safety_level, confidence, processing_time, alerts, color_analysis
-      ) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)`,
-            Object.values(dbData), function(err) {
-                if (err) {
-                    console.error('❌ Database error:', err);
-                } else {
-                    console.log('✅ Test results saved to database');
-                }
-            });
-
-        if (safetyLevel === 'Unsafe') {
-            const alertId = uuidv4();
-            db.run(`INSERT INTO water_alerts (id, test_id, alert_type, severity, message, latitude, longitude)
-                VALUES (?, ?, ?, ?, ?, ?, ?)`,
-                [alertId, testId, 'contamination', 'high', `Unsafe water detected: ${alerts.join(', ')}`,
-                    parseFloat(latitude) || null, parseFloat(longitude) || null]);
-            console.log('🚨 Safety alert created');
-        }
-
-        setTimeout(() => {
-            [preprocessedPath, processedImagePath].forEach(p => {
-                if (fs.existsSync(p) && p !== imagePath) {
-                    fs.unlinkSync(p);
-                }
-            });
-        }, 5000);
-
-        console.log(`✅ Analysis completed in ${processingTime.toFixed(2)}s`);
-
-        res.json({
-            success: true,
-            testId: testId,
-            results: {
-                ph: parseFloat(ph.toFixed(1)),
-                chlorine: parseFloat(chlorine.toFixed(1)),
-                nitrates: Math.round(nitrates),
-                hardness: Math.round(hardness),
-                alkalinity: Math.round(alkalinity),
-                bacteria: bacteria
-            },
-            overallQuality: overallQuality,
-            safetyLevel: safetyLevel,
-            alerts: alerts,
-            recommendations: recommendations,
-            confidence: Math.round(analysisResult.confidence || 95),
-            processingTime: parseFloat(processingTime.toFixed(2)),
-            colorAccuracy: analysisResult.colorAccuracy || '94%',
-            processingMethod: analysisResult.processingMethod || 'AI Analysis',
-            colorChannels: analysisResult.colorChannels || {},
-            timestamp: new Date().toISOString(),
-            location: {
-                latitude: parseFloat(latitude) || null,
-                longitude: parseFloat(longitude) || null
-            }
-        });
-
-    } catch (error) {
-        console.error('❌ Analysis error:', error);
-        res.status(500).json({
-            error: 'Analysis failed',
-            details: error.message,
-            timestamp: new Date().toISOString()
-        });
-    }
-});
-
-// Get water quality map data
-app.get('/api/water-map', (req, res) => {
-    const { lat, lng, radius = 10 } = req.query;
-
-    let query = `SELECT id, latitude, longitude, water_source, overall_quality, 
-                        safety_level, timestamp, alerts, ph, chlorine, nitrates 
-                 FROM water_tests 
-                 WHERE latitude IS NOT NULL AND longitude IS NOT NULL`;
-
-    let params = [];
-
-    if (lat && lng) {
-        const latRadius = radius / 111;
-        const lngRadius = radius / (111 * Math.cos(lat * Math.PI / 180));
-
-        query += ` AND latitude BETWEEN ? AND ? AND longitude BETWEEN ? AND ?`;
-        params = [
-            parseFloat(lat) - latRadius,
-            parseFloat(lat) + latRadius,
-            parseFloat(lng) - lngRadius,
-            parseFloat(lng) + lngRadius
-        ];
-    }
-
-    query += ` ORDER BY timestamp DESC LIMIT 1000`;
-
-    db.all(query, params, (err, rows) => {
-        if (err) {
-            res.status(500).json({ error: 'Database error' });
-            return;
-        }
-
-        const mapData = rows.map(row => ({
-            id: row.id,
-            latitude: row.latitude,
-            longitude: row.longitude,
-            waterSource: row.water_source,
-            quality: row.overall_quality,
-            safety: row.safety_level,
-            timestamp: row.timestamp,
-            alerts: JSON.parse(row.alerts || '[]'),
-            parameters: {
-                ph: row.ph,
-                chlorine: row.chlorine,
-                nitrates: row.nitrates
-            }
-        }));
-
-        res.json({ success: true, data: mapData, count: mapData.length });
-    });
-});
-
-// --- STATIC FILE SERVING FOR PRODUCTION ---
-// This is the crucial part for serving your React app in production.
-// It serves the built React app from the 'web/build' folder.
-const buildPath = path.join(__dirname, '..', 'web', 'build');
-app.use(express.static(buildPath));
-
-// The "catchall" handler: for any request that doesn't match one of our API routes,
-// send back the React app's index.html file. This allows React Router to handle the route.
-app.get('*', (req, res) => {
-    res.sendFile(path.join(buildPath, 'index.html'));
-});
-
-// --- Start Server ---
-app.listen(PORT, () => {
-    console.log(`🌿 GreenPlus by GXS Main Backend Server running on port ${PORT}`);
-    console.log(`🚀 Serving production React app from: ${buildPath}`);
-});
+ const express = require('express');
+ const cors = require('cors');
+ const multer = require('multer');
+ const path = require('path');
+ const fs = require('fs');
+ const { spawn } = require('child_process');
+ const sqlite3 = require('sqlite3').verbose();
+ const sharp = require('sharp');
+ const { v4: uuidv4 } = require('uuid');
+ require('dotenv').config();
+ 
+ const app = express();
+ // Hugging Face and other hosts provide the PORT environment variable. Default to 5000 for local dev.
+ const PORT = process.env.PORT || 5000;
+ 
+ // --- Middleware ---
+ app.use(cors());
+ app.use(express.json());
+ app.use('/uploads', express.static(path.join(__dirname, 'uploads')));
+ 
+ // --- Directory Setup ---
+ // Create ephemeral directories for temporary file uploads and processing.
+ // The Dockerfile ensures these exist and have the correct permissions.
+ const ephemeralDirs = ['uploads', 'temp', 'results'];
+ ephemeralDirs.forEach(dir => {
+   const dirPath = path.join(__dirname, dir);
+   if (!fs.existsSync(dirPath)) {
+     fs.mkdirSync(dirPath, { recursive: true });
+   }
+ });
+ 
+ // --- In-Memory Database Setup ---
+ // For environments without persistent storage, use an in-memory database.
+ // Data will be lost on restart, which is acceptable for a demo/prototype.
+ const db = new sqlite3.Database(':memory:', (err) => {
+     if (err) {
+         console.error('Error opening in-memory database', err.message);
+     } else {
+         console.log('Connected to the SQLite in-memory database.');
+         console.log('NOTE: Database is in-memory and will be reset on application restart.');
+     }
+ });
+ 
+ db.serialize(() => {
+     db.run(`CREATE TABLE IF NOT EXISTS water_tests (
+       id TEXT PRIMARY KEY,
+       timestamp DATETIME DEFAULT CURRENT_TIMESTAMP,
+       user_id TEXT,
+       latitude REAL,
+       longitude REAL,
+       water_source TEXT,
+       image_path TEXT,
+       ph REAL,
+       chlorine REAL,
+       nitrates REAL,
+       hardness REAL,
+       alkalinity REAL,
+       bacteria INTEGER,
+       overall_quality TEXT,
+       safety_level TEXT,
+       confidence REAL,
+       processing_time REAL,
+       alerts TEXT,
+       color_analysis TEXT
+     )`);
+   
+     db.run(`CREATE TABLE IF NOT EXISTS water_alerts (
+       id TEXT PRIMARY KEY,
+       test_id TEXT,
+       alert_type TEXT,
+       severity TEXT,
+       message TEXT,
+       timestamp DATETIME DEFAULT CURRENT_TIMESTAMP,
+       latitude REAL,
+       longitude REAL,
+       FOREIGN KEY(test_id) REFERENCES water_tests(id)
+     )`);
+ });
+ 
+ 
+ // --- MULTER CONFIG FOR FILE UPLOADS ---
+ const storage = multer.diskStorage({
+   destination: (req, file, cb) => {
+     cb(null, path.join(__dirname, 'temp/'));
+   },
+   filename: (req, file, cb) => {
+     const uniqueName = `${file.fieldname}-${Date.now()}-${Math.round(Math.random() * 1E9)}${path.extname(file.originalname)}`;
+     cb(null, uniqueName);
+   }
+ });
+ 
+ const upload = multer({ 
+   storage: storage,
+   limits: { fileSize: 50 * 1024 * 1024 }, // 50MB general limit
+ });
+ 
+ 
+ // --- HELPER FUNCTIONS ---
+ function callPythonScript(scriptName, ...args) {
+     return new Promise((resolve, reject) => {
+       const scriptPath = path.join(__dirname, 'python', scriptName);
+       const pythonProcess = spawn('python3', [scriptPath, ...args]);
+       
+       let dataString = '';
+       let errorString = '';
+   
+       pythonProcess.stdout.on('data', (data) => { dataString += data.toString(); });
+       pythonProcess.stderr.on('data', (data) => { errorString += data.toString(); });
+   
+       pythonProcess.on('close', (code) => {
+         if (code === 0) {
+           try {
+             resolve(JSON.parse(dataString));
+           } catch (error) {
+             console.error(`Error parsing JSON from ${scriptName}:`, dataString);
+             reject(new Error(`Failed to parse Python output from ${scriptName}`));
+           }
+         } else {
+           console.error(`Error in ${scriptName} (code ${code}): ${errorString}`);
+           reject(new Error(errorString));
+         }
+       });
+     });
+ }
+ 
+ // --- API ROUTES ---
+ 
+ // Health check endpoint
+ app.get('/api/health', (req, res) => {
+   res.json({ status: 'ok', message: 'Backend is running' });
+ });
+ 
+ // --- BIODIVERSITYEAR AUDIO ANALYSIS ENDPOINT ---
+ app.post('/api/analyze-audio', upload.single('audioFile'), async (req, res) => {
+     if (!req.file) return res.status(400).json({ message: 'Audio file is missing.' });
+     
+     try {
+         console.log('▶️ Calling Python AI script for audio analysis...');
+         const result = await callPythonScript('audio_analyzer.py', req.file.path);
+         res.status(200).json(result);
+     } catch (error) {
+         res.status(500).json({ message: 'Error during audio analysis.', error: error.message });
+     } finally {
+         fs.unlink(req.file.path, (err) => {
+             if (err) console.error(`- Error deleting temp audio file: ${err.message}`);
+         });
+     }
+ });
+ 
+ // --- BIO-STREAM AI DNA ANALYSIS ENDPOINT ---
+ app.post('/api/analyze-dna', upload.single('dnaFile'), async (req, res) => {
+   if (!req.file) return res.status(400).json({ message: 'DNA file is missing.' });
+ 
+   try {
+       console.log('▶️ Calling Python AI script for DNA analysis...');
+       const result = await callPythonScript('dna_analyzer.py', req.file.path);
+       res.status(200).json(result);
+   } catch (error) {
+       res.status(500).json({ message: 'Error during DNA analysis.', error: error.message });
+   } finally {
+       fs.unlink(req.file.path, (err) => {
+           if (err) console.error(`- Error deleting temp DNA file: ${err.message}`);
+       });
+   }
+ });
+ 
+ // --- PHANTOM FOOTPRINT, E-WASTE, AND OTHER JSON-BASED ENDPOINTS ---
+ function createJsonAnalysisEndpoint(apiPath, scriptName, logMessage) {
+     app.post(apiPath, (req, res) => {
+         console.log(`✅ Backend: Received ${logMessage} request.`);
+         const pythonProcess = spawn('python3', [path.join(__dirname, 'python', scriptName)]);
+ 
+         let analysisResult = '';
+         let errorOutput = '';
+ 
+         pythonProcess.stdin.write(JSON.stringify(req.body));
+         pythonProcess.stdin.end();
+ 
+         pythonProcess.stdout.on('data', (data) => { analysisResult += data.toString(); });
+         pythonProcess.stderr.on('data', (data) => { errorOutput += data.toString(); });
+ 
+         pythonProcess.on('close', (code) => {
+             if (code === 0) {
+                 try {
+                     res.status(200).json(JSON.parse(analysisResult));
+                 } catch (e) {
+                     res.status(500).json({ message: `Failed to parse analysis result for ${logMessage}.` });
+                 }
+             } else {
+                 res.status(500).json({ message: `Error during ${logMessage} analysis.`, error: errorOutput });
+             }
+         });
+     });
+ }
+ 
+ createJsonAnalysisEndpoint('/api/analyze-footprint', 'phantom_footprint_analyzer.py', 'Phantom Footprint');
+ createJsonAnalysisEndpoint('/api/analyze-ewaste', 'ewaste_analyzer.py', 'E-Waste');
+ 
+ // --- AQUALENS WATER ANALYSIS ENDPOINT ---
+ app.post('/api/analyze-water', upload.single('image'), async (req, res) => {
+     const startTime = Date.now();
+     if (!req.file) return res.status(400).json({ error: 'No image file provided' });
+   
+     const { waterSource, latitude, longitude, userId } = req.body;
+     const imagePath = req.file.path;
+     const testId = uuidv4();
+   
+     try {
+       console.log(`🧪 Starting water analysis for test ${testId}`);
+   
+       // Preprocess image with Sharp
+       const preprocessedPath = path.join(__dirname, 'temp', `preprocessed_${testId}.jpg`);
+       await sharp(imagePath)
+         .resize(800, 600, { fit: 'inside' })
+         .normalize()
+         .toFile(preprocessedPath);
+   
+       // AI analysis with Python
+       const analysisResult = await callPythonScript('water_analysis.py', preprocessedPath, waterSource || 'unknown');
+       console.log('✅ AI analysis completed');
+       
+       const processingTime = (Date.now() - startTime) / 1000;
+   
+       // Determine overall quality and safety
+       const { ph, chlorine, nitrates, hardness, alkalinity, bacteria } = analysisResult;
+       let overallQuality = 'Excellent';
+       let safetyLevel = 'Safe';
+       let alerts = [];
+       let recommendations = [];
+   
+       if (ph < 6.5 || ph > 8.5) {
+         alerts.push(`pH levels outside safe range: ${ph.toFixed(1)}`);
+         safetyLevel = 'Caution';
+         overallQuality = 'Good';
+       }
+       if (chlorine > 4.0) {
+         alerts.push(`High chlorine levels: ${chlorine.toFixed(1)} ppm`);
+         safetyLevel = 'Unsafe';
+         overallQuality = 'Poor';
+       }
+       if (nitrates > 10) {
+         alerts.push(`Elevated nitrate levels: ${nitrates} ppm`);
+         safetyLevel = 'Unsafe';
+         overallQuality = 'Poor';
+       }
+       if (bacteria > 0) {
+         alerts.push('Bacterial contamination detected');
+         safetyLevel = 'Unsafe';
+         overallQuality = 'Poor';
+       }
+   
+       // Save to database
+       const dbData = {
+         id: testId,
+         user_id: userId || null,
+         latitude: parseFloat(latitude) || null,
+         longitude: parseFloat(longitude) || null,
+         water_source: waterSource || 'Unknown',
+         image_path: imagePath,
+         ph, chlorine, nitrates, hardness, alkalinity, bacteria,
+         overall_quality: overallQuality,
+         safety_level: safetyLevel,
+         confidence: analysisResult.confidence || 95,
+         processing_time: processingTime,
+         alerts: JSON.stringify(alerts),
+         color_analysis: JSON.stringify(analysisResult.colorChannels || {})
+       };
+   
+       db.run(`INSERT INTO water_tests (
+         id, user_id, latitude, longitude, water_source, image_path,
+         ph, chlorine, nitrates, hardness, alkalinity, bacteria,
+         overall_quality, safety_level, confidence, processing_time, alerts, color_analysis
+       ) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)`,
+       Object.values(dbData), function(err) {
+         if (err) console.error('❌ Database error:', err);
+         else console.log('✅ Test results saved to database');
+       });
+   
+       if (safetyLevel === 'Unsafe') {
+         const alertId = uuidv4();
+         db.run(`INSERT INTO water_alerts (id, test_id, alert_type, severity, message, latitude, longitude)
+                 VALUES (?, ?, ?, ?, ?, ?, ?)`,
+           [alertId, testId, 'contamination', 'high', `Unsafe water detected: ${alerts.join(', ')}`, 
+            parseFloat(latitude) || null, parseFloat(longitude) || null]);
+       }
+   
+       res.json({
+         success: true,
+         testId,
+         results: { ph, chlorine, nitrates, hardness, alkalinity, bacteria },
+         overallQuality,
+         safetyLevel,
+         alerts,
+         recommendations,
+         confidence: Math.round(analysisResult.confidence || 95),
+         processingTime: parseFloat(processingTime.toFixed(2)),
+       });
+   
+     } catch (error) {
+       console.error('❌ Analysis error:', error);
+       res.status(500).json({ error: 'Analysis failed', details: error.message });
+     } finally {
+         fs.unlink(imagePath, (err) => {
+             if (err) console.error(`- Error deleting temp image file: ${err.message}`);
+         });
+     }
+ });
+ 
+ // Get water quality map data
+ app.get('/api/water-map', (req, res) => {
+     db.all(`SELECT id, latitude, longitude, overall_quality, safety_level, timestamp 
+             FROM water_tests 
+             WHERE latitude IS NOT NULL AND longitude IS NOT NULL
+             ORDER BY timestamp DESC LIMIT 1000`, [], (err, rows) => {
+       if (err) {
+         res.status(500).json({ error: 'Database error' });
+         return;
+       }
+       res.json({ success: true, data: rows });
+     });
+ });
+ 
+ // --- STATIC FILE SERVING FOR PRODUCTION ---
+ // This serves the built React app from the 'web/build' folder.
+ const buildPath = path.join(__dirname, '..', 'web', 'build');
+ app.use(express.static(buildPath));
+ console.log(`Serving production React app from: ${buildPath}`);
+ 
+ // The "catchall" handler: for any request that doesn't match an API route,
+ // send back the React app's index.html file.
+ app.get('*', (req, res) => {
+   res.sendFile(path.join(buildPath, 'index.html'));
+ });
+ 
+ // --- Start Server ---
+ app.listen(PORT, () => {
+   console.log(`🌿 GreenPlus by GXS Main Backend Server running on port ${PORT}`);
+ });
+ 
+ module.exports = app;