const express = require('express');
const axios = require('axios');
const app = express();
const path = require('path');

// Set EJS as the view engine
app.set('view engine', 'ejs');

// Specify the views directory
app.set('views', path.join(__dirname, 'views'));

// Middleware to parse JSON request body
app.use(express.json());

// Serve static files (CSS, JavaScript, images, etc.)
app.use(express.static('public'));

// Search endpoint
app.get('/search', async (req, res) => {
    try {
        // Extract search query from request query parameters
        const { query, page = 1, pageSize = 10 } = req.query;

        // Validate search query
        if (!query) {
            return res.status(400).json({ error: 'Query parameter is required' });
        }

        // Calculate start offset for pagination
        const start = (page - 1) * pageSize;

        // Sanitize search query to prevent code injection
        const sanitizedQuery = sanitizeQuery(query);

        // Send search query to Solr
        const response = await axios.get(solrUrl + '/select', {
            params: {
                q: `text:${sanitizedQuery}`, // Query string with field name
		hl: 'true',
		'hl.method': 'unified',
		'hl.fl': '*',
		'hl.snippets': 5,
		'hl.tag.pre': '<b class=\"result-highlight\">',
		'hl.tag.post': '</b>',
		start, // Start offset for pagination
                rows: 10, // Number of rows to return
                wt: 'json', // Response format (JSON)
            },
        });

        // Extract search results from Solr response
        const searchResults = response.data.response.docs;
        const highlightedSnippets = response.data.highlighting;

        // Calculate total number of results (needed for pagination)
        const totalResults = response.data.response.numFound;

        // Calculate total number of pages
        const totalPages = Math.ceil(totalResults / pageSize);

        // Send search results as JSON response
        //res.json({ searchResults, highlightedSnippets });
	res.render('search-results', { query, searchResults, highlightedSnippets, page, pageSize, totalResults, totalPages });
    } catch (error) {
        console.error('Error searching Solr:', error.message);
        res.status(500).json({ error: 'Internal server error' });
    }
});

// Function to sanitize search query to prevent code injection
function sanitizeQuery(query) {
    // Remove any characters that are not alphanumeric or whitespace
    return query.replace(/[^\w\s"]/gi, '');
}

// Start server
const solrUrl = 'http://solr.services.cleveland.daball.me:8983/solr/my_core'; // URL of your Solr instance
const PORT = process.env.PORT || 3000;
app.listen(PORT, () => {
    console.log(`Server is running on port ${PORT}`);
});