const express = require('express');
const mysql = require('mysql2');
const path = require('path');

const app = express();
const PORT = process.env.PORT || 3000;

// Database connection pool
const pool = mysql.createPool({
    host: process.env.DB_HOST || 'localhost',
    port: process.env.DB_PORT || 3306,
    user: process.env.DB_USER || '570005354',
    password: process.env.DB_PASS || '570005354',
    database: process.env.DB_NAME || 'shopdb',
    waitForConnections: true,
    connectionLimit: 10,
    queueLimit: 0
});

// Promisify for async/await
const promisePool = pool.promise();

// Serve static files
app.use(express.static('public'));

// API endpoint to get notifications
app.get('/api/notifications', async (req, res) => {
    try {
        const now = new Date();
        const future = new Date(now.getTime() + (72 * 60 * 60 * 1000)); // 72 hours from now

        const [rows] = await promisePool.query(
            `SELECT n.notificationid, n.notification, n.starttime, n.endtime, n.ticketnumber, n.link,
                    n.isactive, n.isshopfloor, nt.typename, nt.typecolor
             FROM notifications n
             LEFT JOIN notificationtypes nt ON n.notificationtypeid = nt.notificationtypeid
             WHERE n.isactive = 1
             AND n.isshopfloor = 1
             AND (
                 (n.starttime <= ? AND (n.endtime IS NULL OR n.endtime >= ?))
                 OR (n.starttime BETWEEN ? AND ?)
             )
             ORDER BY n.starttime ASC`,
            [future, now, now, future]
        );

        // Categorize notifications
        const currentEvents = [];
        const upcomingEvents = [];

        rows.forEach(notification => {
            const start = new Date(notification.starttime);
            const end = notification.endtime ? new Date(notification.endtime) : null;

            if (start <= now && (end === null || end >= now)) {
                currentEvents.push(notification);
            } else {
                upcomingEvents.push(notification);
            }
        });

        // Sort current events by severity priority, then by starttime
        // Priority: Incident (danger) > Change (warning) > Awareness/TBD (success)
        const severityPriority = {
            'danger': 1,   // Incident - highest priority
            'warning': 2,  // Change
            'success': 3,  // Awareness/TBD - lowest priority
            'secondary': 4 // Fallback
        };

        currentEvents.sort((a, b) => {
            const priorityA = severityPriority[a.typecolor] || 4;
            const priorityB = severityPriority[b.typecolor] || 4;

            // First sort by priority
            if (priorityA !== priorityB) {
                return priorityA - priorityB;
            }

            // If same priority, sort by starttime (earliest first)
            return new Date(a.starttime) - new Date(b.starttime);
        });

        // Upcoming events stay sorted by starttime only
        upcomingEvents.sort((a, b) => {
            return new Date(a.starttime) - new Date(b.starttime);
        });

        res.json({
            success: true,
            timestamp: new Date().toISOString(),
            current: currentEvents,
            upcoming: upcomingEvents
        });

    } catch (error) {
        console.error('Database error:', error);
        res.status(500).json({
            success: false,
            error: 'Database error: ' + error.message
        });
    }
});

// Health check endpoint
app.get('/health', (req, res) => {
    res.json({ status: 'ok', timestamp: new Date().toISOString() });
});

// Start server
app.listen(PORT, () => {
    console.log(`Shopfloor Dashboard running on port ${PORT}`);
    console.log(`Access at: http://localhost:${PORT}`);
});

// Graceful shutdown
process.on('SIGTERM', () => {
    console.log('SIGTERM signal received: closing HTTP server');
    pool.end(() => {
        console.log('Database pool closed');
        process.exit(0);
    });
});