// 数字滚动效果 - 使用 Intersection Observer
console.log('Number counter script loaded');

// 数字计数器类
class NumberCounter {
    constructor(element) {
        this.element = element;
        this.target = this.parseTargetNumber();
        this.isAnimating = false;
        this.hasAnimated = false;
        
        console.log('NumberCounter created for:', this.element.className, 'Target:', this.target);
    }

    parseTargetNumber() {
        const originalText = this.element.textContent.trim();
        console.log('Parsing target number from:', originalText);
        
        // 移除逗号并解析数字
        const number = parseInt(originalText.replace(/,/g, ''));
        
        if (isNaN(number)) {
            console.error('Invalid number:', originalText);
            return 0;
        }
        
        console.log('Parsed number:', number);
        return number;
    }

    animate(duration = 2000) {
        if (this.isAnimating || this.hasAnimated) {
            console.log('Animation already running or completed for:', this.element.className);
            return;
        }

        console.log('Starting animation for:', this.element.className, 'Target:', this.target);
        
        this.isAnimating = true;
        const start = 0;
        const startTime = performance.now();

        const update = (currentTime) => {
            const elapsed = currentTime - startTime;
            const progress = Math.min(elapsed / duration, 1);

            // 缓动函数 - easeOutQuart
            const easeOutQuart = 1 - Math.pow(1 - progress, 4);
            const current = Math.floor(start + (this.target - start) * easeOutQuart);

            // 格式化数字（添加千位分隔符）
            // const formatted = current.toString().replace(/\B(?=(\d{3})+(?!\d))/g, ',');
            // this.element.textContent = formatted;
            this.element.textContent = current;

            if (progress < 1) {
                requestAnimationFrame(update);
            } else {
                // 确保最终显示正确的目标值
                // const finalFormatted = this.target.toString().replace(/\B(?=(\d{3})+(?!\d))/g, ',');
                // this.element.textContent = finalFormatted;
                this.element.textContent = this.target;
                
                // 添加动画完成类
                this.element.classList.add('animated');
                
                this.isAnimating = false;
                this.hasAnimated = true;
                
                console.log('Animation completed for:', this.element.className, 'Final value:', finalFormatted);
            }
        };

        requestAnimationFrame(update);
    }
}

// 等待页面加载完成
window.addEventListener('load', function() {
    console.log('Window load event fired');
    
    // 查找数字元素
    const numberElements = document.querySelectorAll('.number-1, .number-2, .number-3');
    console.log('Found number elements:', numberElements.length);

    if (numberElements.length === 0) {
        console.error('No number elements found!');
        return;
    }

    // 显示原始内容
    numberElements.forEach((element, index) => {
        console.log(`Element ${index + 1} (${element.className}) original content:`, element.textContent);
    });

    // 创建数字计数器实例
    const counters = Array.from(numberElements).map(element => new NumberCounter(element));

    // 创建 Intersection Observer
    const observer = new IntersectionObserver((entries) => {
        entries.forEach(entry => {
            if (entry.isIntersecting) {
                console.log('Element entered viewport:', entry.target.className);
                
                // 找到对应的计数器并开始动画
                const counter = counters.find(c => c.element === entry.target);
                if (counter) {
                    counter.animate(2000);
                }
                
                // 一旦动画开始，就不再观察这个元素
                observer.unobserve(entry.target);
            }
        });
    }, {
        threshold: 0.5, // 当元素50%可见时触发
        rootMargin: '0px 0px -50px 0px' // 稍微提前触发
    });

    // 开始观察所有数字元素
    numberElements.forEach(element => {
        observer.observe(element);
        console.log('Started observing element:', element.className);
    });
});

// 添加全局函数用于手动测试
window.testNumberAnimation = function() {
    console.log('Manual test triggered');
    const elements = document.querySelectorAll('.number-1, .number-2, .number-3');
    elements.forEach((el, i) => {
        console.log(`Element ${i + 1}:`, el.textContent);
    });
};