# -*- coding: utf-8 -*-
"""
索引合并脚本 - 用于合并多人处理的知识库索引
将多个 index_data 文件夹合并成一个统一的索引

使用方法：
1. 将各人处理好的 index_data 文件夹重命名后放到 to_merge/ 目录
   例如: to_merge/index_data_张三/, to_merge/index_data_李四/
2. 运行: python merge_index.py
3. 合并后的索引会保存到 index_data/ 目录
"""
import os
import sys
import json
import shutil

# 添加当前目录到路径
sys.path.insert(0, os.path.dirname(os.path.abspath(__file__)))

from config import INDEX_DIR, EMBEDDING_MODEL, OLLAMA_URL
from vector_store import vector_store

# 待合并的文件夹
MERGE_DIR = os.path.join(os.path.dirname(os.path.abspath(__file__)), 'to_merge')

def load_documents_from_folder(folder_path):
    """从文件夹加载文档数据"""
    docs_file = os.path.join(folder_path, 'documents.json')
    if not os.path.exists(docs_file):
        print(f"  警告: {folder_path} 中没有 documents.json")
        return []
    
    try:
        with open(docs_file, 'r', encoding='utf-8') as f:
            data = json.load(f)
            return data.get('documents', [])
    except Exception as e:
        print(f"  错误: 读取 {docs_file} 失败: {e}")
        return []

def merge_indexes():
    """合并多个索引"""
    print("=" * 60)
    print("索引合并工具")
    print("=" * 60)
    
    # 检查合并目录
    if not os.path.exists(MERGE_DIR):
        os.makedirs(MERGE_DIR)
        print(f"已创建合并目录: {MERGE_DIR}")
        print(f"请将各人处理好的 index_data 文件夹放到此目录中")
        print(f"例如: {MERGE_DIR}/index_data_张三/")
        return
    
    # 扫描待合并的文件夹
    folders = []
    for name in os.listdir(MERGE_DIR):
        folder_path = os.path.join(MERGE_DIR, name)
        if os.path.isdir(folder_path):
            docs_file = os.path.join(folder_path, 'documents.json')
            if os.path.exists(docs_file):
                folders.append((name, folder_path))
    
    if not folders:
        print(f"在 {MERGE_DIR} 中没有找到有效的索引文件夹")
        print(f"请确保文件夹中包含 documents.json 文件")
        return
    
    print(f"找到 {len(folders)} 个待合并的索引:")
    for name, path in folders:
        print(f"  - {name}")
    print()
    
    # 确认合并
    confirm = input("是否开始合并？这将覆盖现有的 index_data (y/n): ").strip().lower()
    if confirm != 'y':
        print("已取消")
        return
    
    # 收集所有文档
    all_documents = []
    all_files = set()
    
    print()
    print("正在收集文档...")
    for name, folder_path in folders:
        print(f"  处理: {name}")
        docs = load_documents_from_folder(folder_path)
        
        for doc in docs:
            filename = doc.get('filename', '')
            # 避免重复文件
            if filename and filename not in all_files:
                all_files.add(filename)
                all_documents.append(doc)
        
        print(f"    文档数: {len(docs)}, 累计: {len(all_documents)}")
    
    print()
    print(f"共收集 {len(all_documents)} 个文档块")
    print(f"来自 {len(all_files)} 个不同文件")
    print()
    
    # 清空现有索引
    print("清空现有索引...")
    if os.path.exists(INDEX_DIR):
        shutil.rmtree(INDEX_DIR)
    os.makedirs(INDEX_DIR)
    
    # 重建索引
    print("重建向量索引...")
    print("这可能需要一些时间，请耐心等待...")
    print()
    
    # 初始化向量存储
    vector_store.documents = []
    vector_store.index = None
    
    # 按文件分组处理
    file_docs = {}
    for doc in all_documents:
        filename = doc.get('filename', 'unknown')
        if filename not in file_docs:
            file_docs[filename] = []
        file_docs[filename].append(doc)
    
    total_files = len(file_docs)
    processed = 0
    
    for filename, docs in file_docs.items():
        processed += 1
        print(f"[{processed}/{total_files}] 索引: {filename} ({len(docs)} 块)")
        
        # 提取文本块
        chunks = [doc.get('content', '') for doc in docs]
        metadata = {
            'filename': filename,
            'file_path': docs[0].get('file_path', ''),
            'char_count': sum(len(c) for c in chunks)
        }
        
        try:
            vector_store.add_documents(chunks, metadata)
        except Exception as e:
            print(f"  错误: {e}")
    
    # 保存索引
    print()
    print("保存索引...")
    vector_store.save_index()
    
    # 显示结果
    stats = vector_store.get_stats()
    print()
    print("=" * 60)
    print("合并完成!")
    print("=" * 60)
    print(f"总文件数: {stats['total_files']}")
    print(f"总文本块: {stats['total_chunks']}")
    print(f"索引目录: {INDEX_DIR}")
    print()
    print("提示: 合并完成后可以删除 to_merge/ 目录中的文件")

if __name__ == '__main__':
    merge_indexes()