tools/search.py

import logging
import os
from langchain_core.tools import StructuredTool
from pydantic import BaseModel, Field
from typing import Optional, List
from serpapi import GoogleSearch

logger = logging.getLogger(__name__)

class SearchInput(BaseModel):
    query: str = Field(description="Search query")

async def search_func(query: str) -> List[str]:
    """
    Perform a web search using SerpAPI and return relevant snippets.
    
    Args:
        query (str): The search query to execute.
    
    Returns:
        List[str]: A list of search result snippets.
    """
    try:
        logger.info(f"Executing SerpAPI search for query: {query}")
        params = {
            "q": query,
            "api_key": os.getenv("SERPAPI_API_KEY"),
            "num": 10
        }
        search = GoogleSearch(params)
        results = search.get_dict().get("organic_results", [])
        return [result.get("snippet", "") for result in results if "snippet" in result]
    except Exception as e:
        logger.error(f"SerpAPI search failed for query '{query}': {e}")
        return []

search_tool = StructuredTool.from_function(
    func=search_func,
    name="search_tool",
    args_schema=SearchInput,
    coroutine=search_func
)

class MultiHopSearchInput(BaseModel):
    query: str = Field(description="Multi-hop search query")
    steps: int = Field(description="Number of search steps", ge=1, le=3)
    llm_client: Optional[object] = Field(description="LLM client", default=None)
    llm_type: Optional[str] = Field(description="LLM type", default="together")
    llm_model: Optional[str] = Field(description="LLM model", default="meta-llama/Llama-3.3-70B-Instruct-Turbo-Free")

async def multi_hop_search_func(query: str, steps: int, llm_client: Optional[object] = None, llm_type: Optional[str] = "together", llm_model: Optional[str] = "meta-llama/Llama-3.3-70B-Instruct-Turbo-Free") -> List[str]:
    """
    Perform a multi-hop web search using SerpAPI with iterative query refinement.
    
    Args:
        query (str): The initial multi-hop search query.
        steps (int): Number of search steps to perform (1 to 3).
        llm_client (Optional[object]): LLM client for query refinement.
        llm_type (Optional[str]): Type of LLM (e.g., 'together').
        llm_model (Optional[str]): LLM model name.
    
    Returns:
        List[str]: A list of search result snippets from all steps.
    """
    try:
        logger.info(f"Executing multi-hop search for query: {query}, steps: {steps}")
        results = []
        current_query = query
        
        for step in range(steps):
            logger.info(f"Multi-hop step {step + 1}: {current_query}")
            step_results = await search_func(current_query)
            results.extend(step_results)
            
            if step < steps - 1 and llm_client:
                prompt = f"Given the query '{current_query}' and results: {step_results[:3]}, generate a follow-up search query to refine or expand the search."
                messages = [
                    {"role": "system", "content": "Generate a single search query as a string."},
                    {"role": "user", "content": prompt}
                ]
                if llm_type == "together":
                    response = llm_client.chat.completions.create(
                        model=llm_model,
                        messages=messages,
                        max_tokens=50,
                        temperature=0.7
                    )
                    current_query = response.choices[0].message.content.strip()
                else:
                    logger.warning("LLM not configured for multi-hop refinement")
                    break
        
        return results[:5] if results else ["No results found"]
    except Exception as e:
        logger.error(f"Multi-hop search failed for query '{query}': {e}")
        return [f"Error: {str(e)}"]

multi_hop_search_tool = StructuredTool.from_function(
    func=multi_hop_search_func,
    name="multi_hop_search_tool",
    args_schema=MultiHopSearchInput,
    coroutine=multi_hop_search_func
)