// 基础JavaScript功能

// 返回顶部功能
window.addEventListener('scroll', function() {
    const backToTop = document.getElementById('backToTop');
    if (backToTop) {
        if (window.pageYOffset > 300) {
            backToTop.style.display = 'block';
        } else {
            backToTop.style.display = 'none';
        }
    }
});

function scrollToTop() {
    window.scrollTo({
        top: 0,
        behavior: 'smooth'
    });
}

// 购物车数量更新
function updateCartBadge(count) {
    const badge = document.getElementById('cartBadge');
    if (badge) {
        if (count > 0) {
            badge.textContent = count;
            badge.style.display = 'inline-block';
        } else {
            badge.style.display = 'none';
        }
    }
}

// 通用提示函数
function showAlert(message, type = 'info', duration = 3000) {
    // 移除现有的提示框
    const existingAlerts = document.querySelectorAll('.custom-alert');
    existingAlerts.forEach(alert => alert.remove());

    // 创建新的提示框
    const alertDiv = document.createElement('div');
    alertDiv.className = `alert alert-${getBootstrapAlertType(type)} alert-dismissible fade show custom-alert`;
    alertDiv.style.cssText = `
        position: fixed;
        top: 20px;
        right: 20px;
        z-index: 9999;
        min-width: 300px;
        max-width: 500px;
        box-shadow: 0 4px 12px rgba(0,0,0,0.15);
    `;

    const icon = getAlertIcon(type);
    alertDiv.innerHTML = `
        <div class="d-flex align-items-center">
            <i class="bi ${icon} me-2"></i>
            <div class="flex-grow-1">${message}</div>
            <button type="button" class="btn-close" onclick="this.parentElement.parentElement.remove()"></button>
        </div>
    `;

    document.body.appendChild(alertDiv);

    // 自动消失
    if (duration > 0) {
        setTimeout(() => {
            if (alertDiv.parentNode) {
                alertDiv.classList.remove('show');
                setTimeout(() => {
                    if (alertDiv.parentNode) {
                        alertDiv.remove();
                    }
                }, 150);
            }
        }, duration);
    }

    return alertDiv;
}

// 获取Bootstrap警告类型
function getBootstrapAlertType(type) {
    const typeMap = {
        'success': 'success',
        'error': 'danger',
        'warning': 'warning',
        'info': 'info'
    };
    return typeMap[type] || 'info';
}

// 获取警告图标
function getAlertIcon(type) {
    const iconMap = {
        'success': 'bi-check-circle-fill',
        'error': 'bi-exclamation-triangle-fill',
        'warning': 'bi-exclamation-triangle-fill',
        'info': 'bi-info-circle-fill'
    };
    return iconMap[type] || 'bi-info-circle-fill';
}

// 确认对话框
function showConfirm(message, callback) {
    if (confirm(message)) {
        if (typeof callback === 'function') {
            callback();
        }
        return true;
    }
    return false;
}

// 页面加载完成后的初始化
document.addEventListener('DOMContentLoaded', function() {
    // 当前页面高亮
    const currentPath = window.location.pathname;
    const navLinks = document.querySelectorAll('.navbar-nav .nav-link');

    navLinks.forEach(link => {
        if (link.getAttribute('href') === currentPath) {
            link.classList.add('active');
        }
    });

    // 初始化购物车数量
    updateCartCount();
});

// 通用AJAX错误处理
function handleAjaxError(xhr, defaultMessage = '操作失败，请稍后再试') {
    if (xhr.status === 401) {
        showAlert('请先登录', 'warning');
        setTimeout(() => {
            window.location.href = '/auth/login';
        }, 1500);
    } else if (xhr.status === 403) {
        showAlert('没有权限执行此操作', 'error');
    } else if (xhr.status === 404) {
        showAlert('请求的资源不存在', 'error');
    } else if (xhr.status >= 500) {
        showAlert('服务器错误，请稍后再试', 'error');
    } else {
        showAlert(defaultMessage, 'error');
    }
}

// 通用成功提示（保持向后兼容）
function showSuccessMessage(message) {
    showAlert(message, 'success');
}

// 更新购物车数量
function updateCartCount() {
    fetch('/cart/count')
        .then(response => response.json())
        .then(data => {
            if (data.success) {
                updateCartBadge(data.count);
            }
        })
        .catch(error => {
            console.log('获取购物车数量失败:', error);
        });
}

// 格式化价格
function formatPrice(price) {
    return '¥' + parseFloat(price).toFixed(2);
}

// 格式化数字
function formatNumber(num) {
    return num.toString().replace(/\B(?=(\d{3})+(?!\d))/g, ',');
}

// 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);
        }
    }
}