// 页面加载完成后执行
document.addEventListener('DOMContentLoaded', function() {
    // 初始化图片上传表单
    initUploadImageForm();
    
    // 初始化聊天表单
    initChatForm();
});

// 初始化图片上传表单
function initUploadImageForm() {
    const form = document.getElementById('uploadImageForm');
    const fileInput = document.getElementById('chatImageFile');
    const previewContainer = document.getElementById('uploadPreview');
    const previewImage = document.getElementById('previewImage');
    const chatContainer = document.getElementById('chatContainer');
    const imageTypeElement = document.getElementById('imageType');
    const imageDescriptionElement = document.getElementById('imageDescription');
    
    // 图片选择预览
    fileInput.addEventListener('change', function() {
        if (this.files && this.files[0]) {
            const reader = new FileReader();
            
            reader.onload = function(e) {
                previewImage.src = e.target.result;
                previewContainer.classList.remove('d-none');
            };
            
            reader.readAsDataURL(this.files[0]);
        }
    });
    
    // 表单提交
    form.addEventListener('submit', async function(e) {
        e.preventDefault();
        
        const formData = new FormData(this);
        
        // 显示上传中状态
        const submitButton = form.querySelector('button[type="submit"]');
        const originalButtonText = submitButton.innerHTML;
        submitButton.disabled = true;
        submitButton.innerHTML = '<span class="spinner-border spinner-border-sm" role="status" aria-hidden="true"></span> 上传中...';
        
        try {
            const response = await fetch('/api/upload-chat-image', {
                method: 'POST',
                body: formData
            });
            
            const data = await response.json();
            
            if (data.error) {
                alert(`上传失败: ${data.error}`);
                return;
            }
            
            // 显示图片信息
            if (data.image_type) {
                imageTypeElement.textContent = data.image_type;
                imageTypeElement.classList.remove('d-none');
            } else {
                imageTypeElement.classList.add('d-none');
            }
            
            if (data.description) {
                imageDescriptionElement.textContent = data.description;
                imageDescriptionElement.classList.remove('d-none');
            } else {
                imageDescriptionElement.classList.add('d-none');
            }
            
            // 显示聊天界面
            chatContainer.classList.remove('d-none');
            
            // 添加欢迎消息
            const chatMessages = document.getElementById('chatMessages');
            chatMessages.innerHTML = '';
            
            const welcomeMessage = document.createElement('div');
            welcomeMessage.className = 'message message-assistant';
            
            let welcomeText = '你好！我是AI助手，可以帮你分析这张图片并回答问题。';
            if (data.image_type && data.description) {
                welcomeText += `我看到这是一张${data.image_type}的图片，${data.description}。你有什么想问的吗？`;
            } else {
                welcomeText += '你有什么想问的吗？';
            }
            
            welcomeMessage.innerHTML = `
                <div class="message-content">${welcomeText}</div>
                <div class="message-time">${getCurrentTime()}</div>
            `;
            
            chatMessages.appendChild(welcomeMessage);
            
            // 滚动到底部
            chatMessages.scrollTop = chatMessages.scrollHeight;
            
        } catch (error) {
            alert(`上传失败: ${error.message}`);
        } finally {
            // 恢复按钮状态
            submitButton.disabled = false;
            submitButton.innerHTML = originalButtonText;
        }
    });
}

// 初始化聊天表单
function initChatForm() {
    const form = document.getElementById('chatForm');
    const messageInput = document.getElementById('messageInput');
    const chatMessages = document.getElementById('chatMessages');
    
    form.addEventListener('submit', async function(e) {
        e.preventDefault();
        
        const message = messageInput.value.trim();
        if (!message) return;
        
        // 添加用户消息到聊天界面
        addMessage('user', message);
        
        // 清空输入框
        messageInput.value = '';
        
        // 显示正在输入指示器
        const typingIndicator = document.createElement('div');
        typingIndicator.className = 'typing-indicator';
        typingIndicator.innerHTML = '<span></span><span></span><span></span>';
        chatMessages.appendChild(typingIndicator);
        
        // 滚动到底部
        chatMessages.scrollTop = chatMessages.scrollHeight;
        
        try {
            const response = await fetch('/api/chat', {
                method: 'POST',
                headers: {
                    'Content-Type': 'application/json'
                },
                body: JSON.stringify({
                    message: message
                })
            });
            
            const data = await response.json();
            
            // 移除正在输入指示器
            chatMessages.removeChild(typingIndicator);
            
            if (data.error) {
                alert(`对话失败: ${data.error}`);
                return;
            }
            
            // 添加AI回复到聊天界面
            addMessage('assistant', data.reply);
            
        } catch (error) {
            // 移除正在输入指示器
            if (typingIndicator.parentNode === chatMessages) {
                chatMessages.removeChild(typingIndicator);
            }
            
            alert(`对话失败: ${error.message}`);
        }
    });
}

// 添加消息到聊天界面
function addMessage(role, content) {
    const chatMessages = document.getElementById('chatMessages');
    
    const messageElement = document.createElement('div');
    messageElement.className = `message message-${role}`;
    
    messageElement.innerHTML = `
        <div class="message-content">${formatMessage(content)}</div>
        <div class="message-time">${getCurrentTime()}</div>
    `;
    
    chatMessages.appendChild(messageElement);
    
    // 滚动到底部
    chatMessages.scrollTop = chatMessages.scrollHeight;
}

// 格式化消息内容，支持简单的markdown
function formatMessage(content) {
    // 转义HTML特殊字符
    let formatted = content
        .replace(/&/g, '&amp;')
        .replace(/</g, '&lt;')
        .replace(/>/g, '&gt;');
    
    // 支持加粗
    formatted = formatted.replace(/\*\*(.*?)\*\*/g, '<strong>$1</strong>');
    
    // 支持斜体
    formatted = formatted.replace(/\*(.*?)\*/g, '<em>$1</em>');
    
    // 支持代码
    formatted = formatted.replace(/`(.*?)`/g, '<code>$1</code>');
    
    // 支持换行
    formatted = formatted.replace(/\n/g, '<br>');
    
    return formatted;
}

// 获取当前时间
function getCurrentTime() {
    const now = new Date();
    const hours = now.getHours().toString().padStart(2, '0');
    const minutes = now.getMinutes().toString().padStart(2, '0');
    return `${hours}:${minutes}`;
}