<template>
  <div class="chat-container">
    <!-- 主内容区域 -->
    <div class="main-content">
      <!-- 聊天消息区域 -->
      <div class="chat-messages" ref="messagesContainer">
        <div v-for="(message, index) in messages" :key="index" :class="['message', message.type]">
          <div class="message-content">
            <div class="message-text" v-html="message.text"></div>
            <div v-if="message.type === 'assistant' && message.similarity" class="message-meta">
              相似度: {{ (message.similarity * 100).toFixed(2) }}%
              <div v-if="message.fileBase64">
                相关资料：
                <a  @click="showPreview(message)">{{message.fileName}}</a>
              </div>
            </div>
          </div>
        </div>
        <div v-if="loading" class="message assistant">
          <div class="message-content">
            <div class="message-text">思考中...</div>
          </div>
        </div>
      </div>

      <!-- 文件预览区域 -->
      <div v-if="previewContent" class="file-preview">

        <div class="preview-header">
          <span class="preview-title">文件预览</span>
          <div class="preview-actions">
            <a-button type="link" @click="downloadFile" class="download-btn">
              <DownloadOutlined />
              <span class="btn-text">下载</span>
            </a-button>
            <a-button
              type="text"
              @click="closePreview"
              class="close-btn"
              title="关闭预览"
            >
              <CloseOutlined />
            </a-button>
          </div>
        </div>
        <div class="preview-content">
          <div v-if="previewType === 'txt' || previewType === 'md'" class="text-preview">
            <pre>{{ previewContent }}</pre>
          </div>
          <div v-else-if="previewType === 'pdf'" class="pdf-preview" ref="pdfPreview"></div>
          <div v-else-if="previewType === 'docx'" class="docx-preview" ref="docxPreview"></div>
          <div v-else-if="previewType === 'doc'" class="unsupported-preview">
            不支持预览 DOC 格式的文件，请下载后使用本地软件查看
          </div>
          <div v-else class="unsupported-preview">
            不支持预览 {{ previewType.toUpperCase() }} 格式的文件
          </div>
        </div>
      </div>
    </div>
    <div>
      <a-button
        style="margin-left: 1%;
        background-color: white;
        color: #666;
        border: 1px solid rgba(0, 0, 0, 0.1);
        border-radius: 16px;
        cursor: pointer;
        font-size: 14px;
        padding: 2px 10px;
        width: max-content;
        margin-right: 6px;
        white-space: nowrap;
        transition: all 300ms ease;
"
        v-for="(btn, index) in buttonList"
        :key="index"
        type="primary"
        class="action-button"
        @click="sendButtonMessage(btn.buttonValues)"
      >
        {{ btn.buttonName }}
      </a-button>
    </div>

    <!-- 输入区域 -->
    <div class="chat-input">
      <a-input
        v-model:value="inputMessage"
        placeholder="请输入您的问题..."
        @pressEnter="sendMessage"
        :disabled="loading"
      />
      <a-button
        type="primary"
        @click="sendMessage"
        :loading="loading"
        :disabled="!inputMessage.trim()"
      >
        发送
      </a-button>
    </div>
  </div>
</template>

<script lang="ts" name="zdy-rag-chat" setup>
import { ref, reactive, nextTick, onMounted, onBeforeUnmount } from 'vue';
import { sendMessage as apiSendMessage , getButtonList} from './ZdyRag.api';
import { useMessage } from '/@/hooks/web/useMessage';
import { CloseOutlined, DownloadOutlined } from '@ant-design/icons-vue';
import * as pdfjsLib from 'pdfjs-dist';
import * as mammoth from 'mammoth';
import { renderAsync } from 'docx-preview';

// 设置PDF.js worker路径
pdfjsLib.GlobalWorkerOptions.workerSrc = '/js/pdf.worker.min.js';

const buttonList = reactive<any[]>([]);
onMounted(async () => {
  try {
    const res = await getButtonList();
    if (res && Array.isArray(res)) {
      buttonList.push(...res);
    } else {
      // createMessage.warning('未获取到按钮列表数据');
    }
  } catch (error) {
    console.error('获取按钮列表失败:', error);
    // createMessage.error('获取按钮列表失败');
  }
});

// 聊天消息数据
const messages = reactive([
  {
    type: 'assistant',
    text: '您好！我是智能助手，请问有什么可以帮您？',
    similarity: null,
    fileBase64: null,
    fileName: null
  }
]);

const inputMessage = ref('');
const loading = ref(false);
const messagesContainer = ref<HTMLElement>();
const previewContent = ref('');
const previewType = ref('');
const previewUrl = ref('');
const currentFile = ref<any>(null);
const pdfPreview = ref<HTMLElement>();
const docxPreview = ref<HTMLElement>();

// 发送消息
const sendMessage = async () => {
  const text = inputMessage.value.trim();
  if (!text || loading.value) return;

  // 添加用户消息
  messages.push({
    type: 'user',
    text: text,
    similarity: null,
    fileBase64: null,
    fileName: null
  });

  inputMessage.value = '';
  loading.value = true;
  closePreview();

  try {
    // 调用API发送消息
    const res = await apiSendMessage({ questionText: text });
    console.log('API响应:', res);

    if (res) {
      const newMessage = {
        type: 'assistant',
        text: formatAnswer(res.answer),
        similarity: res.similarity || null,
        fileBase64: res.fileBase64 || null,
        fileName: res.fileName || ''
      };
      messages.push(newMessage);
    } else {
      // createMessage.error('获取回答失败: 返回数据为空');
    }
  } catch (error: any) {
    console.error('发送消息失败:', error);
    // createMessage.error('发送消息失败: ' + error.message);
  } finally {
    loading.value = false;
    scrollToBottom();
  }
};

const sendButtonMessage = async (buttonValue: string) => {
  if (loading.value) return;

  // 添加用户消息
  messages.push({
    type: 'user',
    text: buttonValue,
    similarity: null,
    fileBase64: null,
    fileName: null
  });

  loading.value = true;
  closePreview();

  try {
    // 调用API发送按钮值
    const res = await apiSendMessage({ questionText: buttonValue });

    if (res) {
      const newMessage = {
        type: 'assistant',
        text: formatAnswer(res.answer),
        similarity: res.similarity || null,
        fileBase64: res.fileBase64 || null,
        fileName: res.fileName || ''
      };
      messages.push(newMessage);
    } else {
      // createMessage.error('获取回答失败: 返回数据为空');
    }
  } catch (error: any) {
    console.error('发送按钮消息失败:', error);
    // createMessage.error('发送按钮消息失败: ' + error.message);
  } finally {
    loading.value = false;
    scrollToBottom();
  }
};

// 增强版showPreview函数
const showPreview = async (message: any) => {
  try {
    // 验证基本数据
    if (!message?.fileBase64 || !message?.fileName) {
      throw new Error('文件数据不完整');
    }

    // 关闭之前的预览
    closePreview();

    // 设置当前文件
    currentFile.value = message;
    const fileExt = getFileExtension(message.fileName);
    previewType.value = fileExt;

    // 根据文件类型处理
    if (['txt', 'md'].includes(fileExt)) {
      // 文本文件处理
      previewContent.value = decodeBase64Content(message.fileBase64);
    } else if (fileExt === 'pdf') {
      // PDF文件处理
      previewContent.value = 'pdf-preview';
      await nextTick(); // 等待DOM更新
      await renderPdf(message.fileBase64);
    } else if (fileExt === 'docx') {
      // DOCX文件处理
      previewContent.value = 'docx-preview';
      await nextTick(); // 等待DOM更新
      await renderDocx(message.fileBase64);
    } else if (fileExt === 'doc') {
      // 不支持DOC格式预览
      previewContent.value = 'unsupported';
      throw new Error('不支持DOC格式预览，请下载后查看');
    } else {
      throw new Error(`不支持的文件类型: ${fileExt}`);
    }
  } catch (error) {
    console.error('预览失败:', error);
    previewContent.value = 'error';
    // createMessage.error(`预览失败: ${error.message}`);
  }
};

// 渲染PDF
const renderPdf = async (base64: string) => {
  if (!pdfPreview.value) return;

  // 清空容器
  pdfPreview.value.innerHTML = '';

  // 将Base64转换为Uint8Array
  const binaryString = atob(base64);
  const bytes = new Uint8Array(binaryString.length);
  for (let i = 0; i < binaryString.length; i++) {
    bytes[i] = binaryString.charCodeAt(i);
  }

  // 加载PDF文档
  const pdfDoc = await pdfjsLib.getDocument({ data: bytes }).promise;

  // 创建Canvas容器
  const container = document.createElement('div');
  container.className = 'pdf-pages';
  pdfPreview.value.appendChild(container);

  // 渲染每一页
  for (let i = 1; i <= pdfDoc.numPages; i++) {
    const page = await pdfDoc.getPage(i);
    const viewport = page.getViewport({ scale: 1.5 });

    const canvas = document.createElement('canvas');
    const context = canvas.getContext('2d');
    canvas.height = viewport.height;
    canvas.width = viewport.width;

    const renderContext = {
      canvasContext: context,
      viewport: viewport
    };

    await page.render(renderContext).promise;

    const pageDiv = document.createElement('div');
    pageDiv.className = 'pdf-page';
    pageDiv.appendChild(canvas);
    container.appendChild(pageDiv);
  }
};

// 渲染DOCX
const renderDocx = async (base64: string) => {
  if (!docxPreview.value) return;

  // 清空容器
  docxPreview.value.innerHTML = '';

  // 将Base64转换为Blob
  const byteString = atob(base64);
  const byteNumbers = new Array(byteString.length);
  for (let i = 0; i < byteString.length; i++) {
    byteNumbers[i] = byteString.charCodeAt(i);
  }
  const byteArray = new Uint8Array(byteNumbers);
  const blob = new Blob([byteArray], {
    type: 'application/vnd.openxmlformats-officedocument.wordprocessingml.document'
  });

  // 使用docx-preview渲染
  await renderAsync(blob, docxPreview.value);
};

// 获取文件扩展名
const getFileExtension = (filename: string): string => {
  const match = filename.match(/\.([0-9a-z]+)(?:[\?#]|$)/i);
  return match ? match[1].toLowerCase() : 'unknown';
};

// Base64解码
const decodeBase64Content = (base64: string): string => {
  try {
    return decodeURIComponent(escape(atob(base64)));
  } catch {
    return atob(base64);
  }
};

// 下载文件
const downloadFile = () => {
  if (!currentFile.value || !currentFile.value.fileBase64 || !currentFile.value.fileName) {
    // createMessage.warning('无法下载文件');
    return;
  }

  try {
    const byteCharacters = atob(currentFile.value.fileBase64);
    const byteNumbers = new Array(byteCharacters.length);
    for (let i = 0; i < byteCharacters.length; i++) {
      byteNumbers[i] = byteCharacters.charCodeAt(i);
    }
    const byteArray = new Uint8Array(byteNumbers);
    const blob = new Blob([byteArray], { type: 'application/octet-stream' });

    const link = document.createElement('a');
    link.href = URL.createObjectURL(blob);
    link.download = currentFile.value.fileName;
    document.body.appendChild(link);
    link.click();
    document.body.removeChild(link);

    // createMessage.success('文件下载开始');
  } catch (error: any) {
    console.error('文件下载失败:', error);
    // createMessage.error('文件下载失败: ' + error.message);
  }
};

// 关闭预览
const closePreview = () => {
  previewContent.value = '';
  previewType.value = '';
  if (previewUrl.value) {
    URL.revokeObjectURL(previewUrl.value);
    previewUrl.value = '';
  }
  currentFile.value = null;

  // 清空预览容器
  if (pdfPreview.value) pdfPreview.value.innerHTML = '';
  if (docxPreview.value) docxPreview.value.innerHTML = '';
};

// 格式化回答内容
const formatAnswer = (answer: string) => {
  // 替换[n]为换行符，然后将换行符转换为<br>标签
  return answer.replace(/\[n\]/g, '\n').replace(/\n/g, '<br>');
};

// 滚动到底部
const scrollToBottom = () => {
  nextTick(() => {
    if (messagesContainer.value) {
      messagesContainer.value.scrollTop = messagesContainer.value.scrollHeight;
    }
  });
};

// 组件卸载时清理资源
onBeforeUnmount(() => {
  closePreview();
});
</script>

<style lang="less" scoped>
/* 样式保持不变 */
.chat-container {
  display: flex;
  flex-direction: column;
  height: calc(100vh - 120px);
  max-width: 1200px;
  margin: 0 auto;
  padding: 20px;
  background-color: #f5f5f5;
  border-radius: 8px;
}

.main-content {
  display: flex;
  flex: 1;
  gap: 20px;
  margin-bottom: 20px;
  overflow: hidden;
}

.chat-messages {
  flex: 1;
  overflow-y: auto;
  padding: 15px;
  background-color: white;
  border-radius: 8px;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
  min-height: 300px;
}

//.file-preview {
//  width: 55%;
//  min-width: 300px;
//  display: flex;
//  flex-direction: column;
//  background-color: white;
//  border-radius: 8px;
//  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
//  overflow: hidden;
//
//  .preview-header {
//    display: flex;
//    justify-content: space-between;
//    align-items: center;
//    padding: 10px 15px;
//    background-color: #f0f0f0;
//    border-bottom: 1px solid #e8e8e8;
//
//    .preview-actions {
//      display: flex;
//      align-items: center;
//      gap: 8px;
//    }
//  }
//
//  .preview-content {
//    flex: 1;
//    overflow: auto;
//    padding: 10px;
//
//    .text-preview {
//      padding: 15px;
//      white-space: pre-wrap;
//      font-family: monospace;
//      line-height: 1.6;
//    }
//
//    .pdf-preview {
//      height: 100%;
//      overflow-y: auto;
//
//      .pdf-pages {
//        display: flex;
//        flex-direction: column;
//        gap: 20px;
//        padding: 10px;
//
//        .pdf-page {
//          border: 1px solid #e8e8e8;
//          box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
//        }
//      }
//    }
//
//    .docx-preview {
//      height: 100%;
//      overflow-y: auto;
//      padding: 20px;
//      background-color: #fff;
//    }
//
//    .unsupported-preview {
//      height: 100%;
//      padding: 20px;
//      display: flex;
//      align-items: center;
//      justify-content: center;
//      color: #ff4d4f;
//      font-weight: 500;
//    }
//  }
//}
.file-preview {
  width: 55%;
  min-width: 300px;
  display: flex;
  flex-direction: column;
  background-color: white;
  border-radius: 8px;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
  overflow: hidden;

  .preview-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px 15px;
    background-color: #f0f0f0;
    border-bottom: 1px solid #e8e8e8;
    font-weight: 500;
    font-size: 14px;

    .preview-actions {
      display: flex;
      align-items: center;
      gap: 10px;

      .ant-btn {
        padding: 0;
        height: auto;
        color: #666;
        display: flex;
        align-items: center;
        transition: color 0.3s;

        &:hover {
          color: #1890ff;
          background: transparent;
        }

        .anticon {
          font-size: 16px;
        }
      }

      .ant-btn-link {
        padding: 0 8px;
      }
    }
  }

  .preview-content {
    flex: 1;
    overflow: auto;
    padding: 10px;

    .text-preview {
      padding: 15px;
      white-space: pre-wrap;
      font-family: monospace;
      line-height: 1.6;
      background-color: #fafafa;
      border-radius: 4px;
    }

    .pdf-preview {
      height: 100%;
      overflow-y: auto;

      .pdf-pages {
        display: flex;
        flex-direction: column;
        gap: 20px;
        padding: 10px;

        .pdf-page {
          border: 1px solid #e8e8e8;
          box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
          background-color: white;
        }
      }
    }

    .docx-preview {
      height: 100%;
      overflow-y: auto;
      padding: 20px;
      background-color: #fff;
      border: 1px solid #f0f0f0;
      border-radius: 4px;
    }

    .unsupported-preview {
      height: 100%;
      padding: 20px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: #ff4d4f;
      font-weight: 500;
      background-color: #fff2f0;
      border-radius: 4px;
      text-align: center;
    }
  }
}

/* 响应式设计 */
@media (max-width: 768px) {
  .file-preview {
    width: 100%;
    min-width: auto;
    max-height: 300px;

    .preview-header {
      padding: 8px 12px;

      .preview-actions {
        gap: 6px;

        .ant-btn-link {
          padding: 0 4px;
        }
      }
    }

    .preview-content {
      padding: 8px;

      .text-preview,
      .docx-preview {
        padding: 10px;
      }
    }
  }
}
.message {
  margin-bottom: 15px;
  display: flex;

  &.user {
    justify-content: flex-end;

    .message-content {
      background-color: #1890ff;
      color: white;
      border-radius: 18px 18px 0 18px;
    }
  }

  &.assistant {
    justify-content: flex-start;

    .message-content {
      background-color: #f0f0f0;
      color: #333;
      border-radius: 18px 18px 18px 0;
    }
  }
}

.message-content {
  max-width: 80%;
  padding: 12px 16px;
  word-wrap: break-word;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

.message-meta {
  font-size: 12px;
  color: #666;
  margin-top: 8px;
  text-align: right;

  a {
    margin-left: 10px;
    color: #1890ff;
    cursor: pointer;

    &:hover {
      text-decoration: underline;
    }
  }
}

.chat-input {
  display: flex;
  gap: 12px;
  padding: 10px 0;

  :deep(.ant-input) {
    flex: 1;
    border-radius: 20px;
    padding: 12px 18px;
    border: 1px solid #d9d9d9;
    transition: all 0.3s;

    &:hover {
      border-color: #40a9ff;
    }

    &:focus {
      box-shadow: 0 0 0 2px rgba(24, 144, 255, 0.2);
    }
  }

  .ant-btn {
    border-radius: 20px;
    padding: 0 24px;
    height: 40px;
    font-weight: 500;
  }
}

/* 响应式设计 */
@media (max-width: 768px) {
  .main-content {
    flex-direction: column;
  }

  .file-preview {
    width: 100%;
    min-width: auto;
    max-height: 300px;
  }

  .message-content {
    max-width: 90%;
  }
}
</style>