// 图片预览功能
document.addEventListener('DOMContentLoaded', function () {
    // 注册页面的学生证照片预览
    const studentIdInput = document.getElementById('student_id_photo');
    if (studentIdInput) {
        studentIdInput.addEventListener('change', function (e) {
            const file = e.target.files[0];
            if (file) {
                const reader = new FileReader();
                reader.onload = function (e) {
                    const preview = document.getElementById('imagePreview');
                    if (preview) {
                        preview.src = e.target.result;
                        preview.style.display = 'block';
                        document.querySelector('#fileUploadArea .file-upload-text').style.display = 'none';
                    }
                };
                reader.readAsDataURL(file);
            }
        });
    }

    // 发帖页面的图片预览
    const postImageInput = document.getElementById('image');
    if (postImageInput) {
        postImageInput.addEventListener('change', function (e) {
            const file = e.target.files[0];
            if (file) {
                const reader = new FileReader();
                reader.onload = function (e) {
                    const preview = document.getElementById('postImagePreview');
                    if (preview) {
                        preview.src = e.target.result;
                        preview.style.display = 'block';
                        document.querySelector('#postImageUploadArea .file-upload-text').style.display = 'none';
                    }
                };
                reader.readAsDataURL(file);
            }
        });
    }

    // Flash消息自动关闭
    const flashMessages = document.querySelectorAll('.flash');
    flashMessages.forEach(function (flash) {
        setTimeout(function () {
            flash.style.animation = 'slideOut 0.3s ease';
            setTimeout(function () {
                flash.remove();
            }, 300);
        }, 5000);
    });

    // 拖拽上传功能
    const uploadAreas = document.querySelectorAll('.file-upload-area');
    uploadAreas.forEach(function (area) {
        area.addEventListener('dragover', function (e) {
            e.preventDefault();
            this.style.borderColor = 'var(--primary-color)';
            this.style.background = 'rgba(99, 102, 241, 0.1)';
        });

        area.addEventListener('dragleave', function (e) {
            e.preventDefault();
            this.style.borderColor = 'var(--border-color)';
            this.style.background = 'transparent';
        });

        area.addEventListener('drop', function (e) {
            e.preventDefault();
            this.style.borderColor = 'var(--border-color)';
            this.style.background = 'transparent';

            const fileInput = this.querySelector('.file-input');
            if (fileInput && e.dataTransfer.files.length) {
                fileInput.files = e.dataTransfer.files;
                // 触发change事件
                const event = new Event('change');
                fileInput.dispatchEvent(event);
            }
        });
    });
});

// slideOut 动画
const style = document.createElement('style');
style.innerHTML = `
@keyframes slideOut {
    from {
        transform: translateX(0);
        opacity: 1;
    }
    to {
        transform: translateX(100%);
        opacity: 0;
    }
}
`;
document.head.appendChild(style);