{
 "cells": [
  {
   "cell_type": "code",
   "execution_count": 2,
   "id": "6b4b5b35",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "True"
      ]
     },
     "execution_count": 2,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "import os\n",
    "from dotenv import load_dotenv\n",
    "load_dotenv()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "id": "86fc8f30",
   "metadata": {},
   "outputs": [],
   "source": [
    "from langchain_community.document_loaders import PyMuPDFLoader\n",
    "from langchain_text_splitters import RecursiveCharacterTextSplitter\n",
    "from langchain_community.embeddings import DashScopeEmbeddings\n",
    "from langchain_community.vectorstores import Chroma\n",
    "from langchain_core.prompts import ChatPromptTemplate\n",
    "from langchain_community.chat_models import ChatTongyi\n",
    "from langchain_core.output_parsers import StrOutputParser\n",
    "\n",
    "# ========== 第一步：加载文档 ==========\n",
    "loader = PyMuPDFLoader(\"./profile.pdf\")\n",
    "pages = loader.load()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "id": "12a71183",
   "metadata": {},
   "outputs": [],
   "source": [
    "# ========== 第二步：清洗数据（可选，根据文档质量决定）==========\n",
    "# clean_pages = [clean_pdf_text(page) for page in pages]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "id": "96e8b2ac",
   "metadata": {},
   "outputs": [],
   "source": [
    "# ========== 第三步：分块 ==========\n",
    "splitter = RecursiveCharacterTextSplitter(\n",
    "    # 分隔符优先级：段落 → 换行 → 句号 → 空格 → 硬切\n",
    "    separators=[\"\\n\\n\", \"\\n\", \"。\", \"！\", \"？\", \" \", \"\"],\n",
    "    # 每个块最大 100 字符\n",
    "    chunk_size=500,\n",
    "    # 相邻块重叠 10 字符（chunk_size 的 20%）\n",
    "    chunk_overlap=100,\n",
    "    # 长度计算函数\n",
    "    length_function=len\n",
    ")\n",
    "docs = splitter.split_documents(pages)\n",
    "# ========== 第四步：向量化 + 存入向量库 ==========\n",
    "embedding_model = DashScopeEmbeddings(\n",
    "    model=\"text-embedding-v3\",\n",
    "    dashscope_api_key=os.getenv(\"DASHSCOPE_API_KEY\")\n",
    ")\n",
    "\n",
    "vectorstore = Chroma.from_documents(\n",
    "    documents=docs,\n",
    "    embedding=embedding_model,\n",
    "    persist_directory=\"./knowledge_db_500_char\"\n",
    ")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 18,
   "id": "c73b682e",
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "吴雅娟是**高级前端工程师**，目前为自由职业者（2024/05至今），此前就职于智库人工智能科技有限公司（2021/08–2024/04）担任Web前端高级工程师，更早前在北京路遥科技有限公司（2016/08–2021/05）任Web前端开发工程师。\n",
      "\n",
      "履历包括：  \n",
      "- **教育背景**：五邑大学本科，2016年毕业；  \n",
      "- **技术能力**：熟悉HTML5/CSS3、ES6+、Vue2/Vue3（含Vuex、Pinia、Vue Router）、React.js（含Redux/Router）、HTTP/TCP协议、浏览器渲染机制、Webpack/Vite工程化等；  \n",
      "- **项目经验**：主导“看数需求”项目（含公式编辑器优化、Zrender高自定义图表开发、IndexedDB缓存、长列表性能优化、展板导出优化）、DMP数据管理系统（RBAC权限控制、数据处理流程优化）及“智慧‘气象+’城市赋能平台”等；  \n",
      "- **其他**：承接向暖小程序等外包项目。\n"
     ]
    }
   ],
   "source": [
    "# ========== 第五步：创建检索器 ==========\n",
    "retriever = vectorstore.as_retriever(search_kwargs={\"k\": 3})\n",
    "\n",
    "# ========== 第六步：提问 ==========\n",
    "query = \"吴雅娟是干什么的？有什么履历？\"\n",
    "relevant_docs = retriever.invoke(query)\n",
    "\n",
    "# ========== 第七步：生成回答 ==========\n",
    "context = \"\\n\\n---\\n\\n\".join([d.page_content for d in relevant_docs])\n",
    "\n",
    "prompt = ChatPromptTemplate.from_template(\"\"\"\n",
    "你是一个专业的知识库助手。请根据以下上下文回答问题。\n",
    "\n",
    "**规则：**\n",
    "- 只基于提供的上下文回答，不要编造\n",
    "- 如果上下文中没有相关信息，直接说「根据现有资料，我找不到这个问题的答案」\n",
    "- 回答要简洁直接，引用原文时用引号\n",
    "\n",
    "**上下文：**\n",
    "{context}\n",
    "\n",
    "**问题：**\n",
    "{question}\n",
    "\"\"\")\n",
    "\n",
    "llm = ChatTongyi(model=\"qwen-plus\", dashscope_api_key=os.getenv(\"DASHSCOPE_API_KEY\"))\n",
    "chain = prompt | llm | StrOutputParser()\n",
    "\n",
    "answer = chain.invoke({\"context\": context, \"question\": query})\n",
    "print(answer)"
   ]
  }
 ],
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