"""Tool definitions for LangGraph agent."""
from langchain_core.tools import tool
from langchain_community.document_loaders import WikipediaLoader, ArxivLoader
from langchain_community.tools.tavily_search import TavilySearchResults

@tool
def multiply(a: int, b: int) -> int:
    """Multiply two numbers."""
    return a * b

@tool
def add(a: int, b: int) -> int:
    """Add two numbers."""
    return a + b

@tool
def subtract(a: int, b: int) -> int:
    """Subtract two numbers."""
    return a - b

@tool
def divide(a: int, b: int) -> float:
    """Divide two numbers."""
    if b == 0:
        raise ValueError("Cannot divide by zero.")
    return a / b

@tool
def modulus(a: int, b: int) -> int:
    """Get modulus of two numbers."""
    return a % b

@tool
def wiki_search(query: str) -> str:
    """Search Wikipedia for a query and return top results."""
    docs = WikipediaLoader(query=query, load_max_docs=2).load()
    return "\n\n".join(doc.page_content for doc in docs)

@tool
def arxiv_search(query: str) -> str:
    """Search Arxiv for a query and return top results."""
    docs = ArxivLoader(query=query, load_max_docs=2).load()
    return "\n\n".join(doc.page_content[:1000] for doc in docs)

@tool
def web_search(query: str) -> str:
    """Search the web using Tavily."""
    docs = TavilySearchResults(max_results=3).invoke(query=query)
    return "\n\n".join(doc.page_content for doc in docs)

# Export list of all tools
TOOLS = [multiply, add, subtract, divide, modulus, wiki_search, arxiv_search, web_search]