from fastapi import FastAPI, HTTPException, Query
from fastapi.middleware.cors import CORSMiddleware
import duckdb
import threading
from contextlib import asynccontextmanager
import os

# Thread-local storage — har thread ka apna connection hoga
# Isse concurrent requests pe crash nahi hoga
_local = threading.local()

PARQUET_URL = "https://huggingface.co/datasets/CodeXDevloper/Inddatainonefile/resolve/main/users_data.parquet"

def get_con():
    """Har thread ke liye alag DuckDB connection dega"""
    if not hasattr(_local, 'con') or _local.con is None:
        con = duckdb.connect()
        con.execute("INSTALL httpfs; LOAD httpfs;")
        con.execute(f"""
            CREATE OR REPLACE VIEW users_view AS 
            SELECT * FROM read_parquet('{PARQUET_URL}')
        """)
        _local.con = con
    return _local.con

@asynccontextmanager
async def lifespan(app: FastAPI):
    print("API start ho rahi hai...")
    # Main thread ka connection startup pe bana lo
    try:
        con = get_con()
        # Ek test query — parquet file check karo
        con.execute("SELECT COUNT(*) FROM users_view").fetchone()
        print("✅ Parquet file load ho gayi! API ready hai.")
    except Exception as e:
        print(f"⚠️ Startup error: {e}")
    yield
    # Cleanup
    if hasattr(_local, 'con') and _local.con:
        _local.con.close()

app = FastAPI(title="Super Fast Search API", lifespan=lifespan)

# CORS — kisi bhi frontend se API call ho sake
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_methods=["GET"],
    allow_headers=["*"],
)

@app.get("/")
def home():
    return {
        "message": "Super Fast Search API online hai!",
        "usage": "/search?mobile=YOUR_NUMBER",
        "status": "running"
    }

@app.get("/health")
def health():
    """Keep-alive ping ke liye yeh endpoint use karo"""
    return {"status": "ok"}

@app.get("/search")
async def search_mobile(mobile: str = Query(..., description="Enter mobile number to search")):
    if not mobile.strip().isdigit():
        return {"status": "error", "message": "Sirf numbers enter karein."}

    try:
        con = get_con()  # Thread-safe connection
        
        query = """
            SELECT mobile, name, fname, address, alt, circle, id, email 
            FROM users_view 
            WHERE CAST(mobile AS VARCHAR) = ?
            LIMIT 1
        """
        result = con.execute(query, [mobile.strip()]).fetchall()

        if not result:
            return {
                "status": "error",
                "message": f"Mobile number {mobile} nahi mila."
            }

        columns = [desc[0] for desc in con.description]
        row_dict = dict(zip(columns, result[0]))

        return {
            "status": "success",
            "data": row_dict
        }

    except Exception as e:
        print(f"Query error: {e}")
        # Connection reset karo agar error aaye
        _local.con = None
        raise HTTPException(status_code=500, detail="Query process nahi ho payi. Dobara try karein.")