// 工具函数集合

// MD5加密函数（使用CryptoJS）
function md5(text) {
    return CryptoJS.MD5(text).toString();
}

// 格式化日期时间
function formatDateTime(date) {
    if (!date) return '';
    const d = new Date(date);
    return d.toLocaleString('zh-CN');
}

// 格式化货币
function formatCurrency(amount) {
    // 处理无效输入
    if (amount === undefined || amount === null || amount === '') {
        return '¥0.00';
    }
    
    // 转换为数字
    const num = parseFloat(amount);
    
    // 检查是否为有效数字
    if (isNaN(num)) {
        return '¥0.00';
    }
    
    return '¥' + num.toFixed(2);
}

// 验证邮箱格式
function validateEmail(email) {
    const re = /^[^\s@]+@[^\s@]+\.[^\s@]+$/;
    return re.test(email);
}

// 验证手机号格式
function validatePhone(phone) {
    const re = /^1[3-9]\d{9}$/;
    return re.test(phone);
}

// 显示提示消息
function showMessage(message, type = 'info') {
    // 创建提示元素
    const alertDiv = document.createElement('div');
    alertDiv.className = `alert alert-${type} alert-dismissible fade show position-fixed`;
    alertDiv.style.top = '20px';
    alertDiv.style.right = '20px';
    alertDiv.style.zIndex = '9999';
    alertDiv.innerHTML = `
        ${message}
        <button type="button" class="btn-close" data-bs-dismiss="alert"></button>
    `;
    
    document.body.appendChild(alertDiv);
    
    // 3秒后自动移除
    setTimeout(() => {
        if (alertDiv.parentNode) {
            alertDiv.parentNode.removeChild(alertDiv);
        }
    }, 3000);
}

// 确认对话框
function confirmDialog(message) {
    return confirm(message);
}

// 加载动画显示/隐藏
function showLoading() {
    // 创建加载遮罩
    const loadingDiv = document.createElement('div');
    loadingDiv.id = 'loading-overlay';
    loadingDiv.className = 'position-fixed top-0 start-0 w-100 h-100 d-flex justify-content-center align-items-center';
    loadingDiv.style.backgroundColor = 'rgba(0,0,0,0.5)';
    loadingDiv.style.zIndex = '9999';
    loadingDiv.innerHTML = `
        <div class="spinner-border text-light" role="status">
            <span class="visually-hidden">加载中...</span>
        </div>
    `;
    
    document.body.appendChild(loadingDiv);
}

function hideLoading() {
    const loadingDiv = document.getElementById('loading-overlay');
    if (loadingDiv) {
        loadingDiv.remove();
    }
}

// 表单验证
function validateForm(formId) {
    const form = document.getElementById(formId);
    const inputs = form.querySelectorAll('input[required], select[required], textarea[required]');
    let isValid = true;
    
    inputs.forEach(input => {
        if (!input.value.trim()) {
            input.classList.add('is-invalid');
            isValid = false;
        } else {
            input.classList.remove('is-invalid');
        }
    });
    
    return isValid;
}

// 数字格式化
function formatNumber(num, decimals = 2) {
    return parseFloat(num).toFixed(decimals);
}

// 百分比计算
function calculatePercentage(part, total) {
    if (total === 0) return 0;
    return (part / total * 100).toFixed(2);
}

// 字符串截取
function truncateString(str, length) {
    if (str.length <= length) return str;
    return str.substring(0, length) + '...';
}

// 生成随机ID
function generateId() {
    return Math.random().toString(36).substr(2, 9);
}

// 深拷贝对象
function deepClone(obj) {
    if (obj === null || typeof obj !== 'object') return obj;
    if (obj instanceof Date) return new Date(obj.getTime());
    if (obj instanceof Array) return obj.map(item => deepClone(item));
    if (typeof obj === 'object') {
        const clonedObj = {};
        for (let key in obj) {
            if (obj.hasOwnProperty(key)) {
                clonedObj[key] = deepClone(obj[key]);
            }
        }
        return clonedObj;
    }
}

// 防抖函数
function debounce(func, wait) {
    let timeout;
    return function executedFunction(...args) {
        const later = () => {
            clearTimeout(timeout);
            func(...args);
        };
        clearTimeout(timeout);
        timeout = setTimeout(later, wait);
    };
}

// 节流函数
function throttle(func, limit) {
    let inThrottle;
    return function() {
        const args = arguments;
        const context = this;
        if (!inThrottle) {
            func.apply(context, args);
            inThrottle = true;
            setTimeout(() => inThrottle = false, limit);
        }
    };
}

// 文件大小格式化
function formatFileSize(bytes) {
    if (bytes === 0) return '0 Bytes';
    const k = 1024;
    const sizes = ['Bytes', 'KB', 'MB', 'GB'];
    const i = Math.floor(Math.log(bytes) / Math.log(k));
    return parseFloat((bytes / Math.pow(k, i)).toFixed(2)) + ' ' + sizes[i];
}

// 图片预览
function previewImage(input, previewElementId) {
    if (input.files && input.files[0]) {
        const reader = new FileReader();
        reader.onload = function(e) {
            const preview = document.getElementById(previewElementId);
            if (preview) {
                preview.innerHTML = `<img src="${e.target.result}" class="img-thumbnail" style="max-width: 200px;">`;
            }
        };
        reader.readAsDataURL(input.files[0]);
    }
}

// 检查浏览器支持
function checkBrowserSupport() {
    const features = {
        localStorage: typeof(Storage) !== "undefined",
        fileUpload: !!window.File && !!window.FileReader && !!window.FileList && !!window.Blob,
        dragAndDrop: 'draggable' in document.createElement('span'),
        canvas: !!document.createElement('canvas').getContext,
        webGL: (function() {
            try {
                const canvas = document.createElement('canvas');
                return !!(window.WebGLRenderingContext && (canvas.getContext('webgl') || canvas.getContext('experimental-webgl')));
            } catch(e) {
                return false;
            }
        })()
    };
    
    return features;
}

// 导出为全局函数
window.Utils = {
    md5,
    formatDateTime,
    formatCurrency,
    validateEmail,
    validatePhone,
    showMessage,
    confirmDialog,
    showLoading,
    hideLoading,
    validateForm,
    formatNumber,
    calculatePercentage,
    truncateString,
    generateId,
    deepClone,
    debounce,
    throttle,
    formatFileSize,
    previewImage,
    checkBrowserSupport
};