class ParticleSimulator {
    constructor(canvasId) {
        this.canvas = document.getElementById(canvasId);
        this.particles = [];
        this.isRunning = false;
        this.animationId = null;
        
        this.init();
    }

    init() {
        this.createParticles(25);
        this.start();
        
        // Add resize listener
        window.addEventListener('resize', () => {
            this.handleResize();
        });
    }

    createParticles(count) {
        this.particles = [];
        const colors = [
            'rgba(14, 165, 233, 0.8)',
            'rgba(100, 116, 139, 0.8)',
            'rgba(2, 132, 199, 0.8)',
            'rgba(71, 85, 105, 0.8)'
        ];

        for (let i = 0; i < count; i++) {
            const size = Math.random() * 8 + 4;
            const particle = {
                x: Math.random() * this.canvas.offsetWidth,
                y: Math.random() * this.canvas.offsetHeight,
                size: size,
                speedX: (Math.random() - 0.5) * 3,
                speedY: (Math.random() - 0.5) * 3,
                color: colors[Math.floor(Math.random() * colors.length)],
                trail: []
            };
            this.particles.push(particle);
        }
    }

    start() {
        this.isRunning = true;
        this.animate();
    }

    stop() {
        this.isRunning = false;
        if (this.animationId) {
            cancelAnimationFrame(this.animationId);
        }
    }

    reset() {
        this.stop();
        this.particles = [];
        this.createParticles(25);
        this.start();
    }

    animate() {
        if (!this.isRunning) return;

        // Clear canvas
        this.canvas.innerHTML = '';

        // Update and draw particles
        this.particles.forEach(particle => {
            // Update position
            particle.x += particle.speedX;
            particle.y += particle.speedY;

            // Boundary check
            if (particle.x <= 0 || particle.x >= this.canvas.offsetWidth) {
                particle.speedX *= -1;
            }
            if (particle.y <= 0 || particle.y >= this.canvas.offsetHeight) {
                particle.speedY *= -1;
            }

            // Add to trail
            particle.trail.push({ x: particle.x, y: particle.y });
            if (particle.trail.length > 10) {
                particle.trail.shift();
            }

            // Draw trail
            particle.trail.forEach((trailPos, index) => {
                const trailElement = document.createElement('div');
                trailElement.className = 'particle-trail';
                trailElement.style.width = `${particle.size * (index / particle.trail.length)}px`;
                trailElement.style.height = `${particle.size * (index / particle.trail.length)}px`;
                trailElement.style.left = `${trailPos.x}px`;
                trailElement.style.top = `${trailPos.y}px`;
                trailElement.style.backgroundColor = particle.color.replace('0.8', `${0.3 * (index / particle.trail.length)}`);
                this.canvas.appendChild(trailElement);
            });

            // Draw particle
            const particleElement = document.createElement('div');
            particleElement.className = 'particle';
            particleElement.style.width = `${particle.size}px`;
            particleElement.style.height = `${particle.size}px`;
            particleElement.style.left = `${particle.x}px`;
            particleElement.style.top = `${particle.y}px`;
            particleElement.style.backgroundColor = particle.color;
            particleElement.style.boxShadow = `0 0 ${particle.size * 2}px ${particle.color}`;
            this.canvas.appendChild(particleElement);
        });

        this.animationId = requestAnimationFrame(() => this.animate());
    }

    handleResize() {
        this.stop();
        this.start();
    }

    updateParticleCount(count) {
        this.stop();
        this.createParticles(count);
        this.start();
    }
}

// Initialize simulator when DOM is loaded
document.addEventListener('DOMContentLoaded', () => {
    const simulator = new ParticleSimulator('simulationCanvas');

    // Add event listeners for control buttons
    document.querySelector('button:nth-child(1)').addEventListener('click', () => {
        simulator.start();
    });

    document.querySelector('button:nth-child(2)').addEventListener('click', () => {
        simulator.stop();
    });

    document.querySelector('button:nth-child(3)').addEventListener('click', () => {
        simulator.reset();
    });

    // Add event listeners for sliders
    const sliders = document.querySelectorAll('input[type="range"]');
    sliders[0].addEventListener('input', (e) => {
        simulator.updateParticleCount(parseInt(e.target.value));
    });
});