from fastapi import FastAPI, HTTPException
from contextlib import asynccontextmanager
import httpx
import re
import os
from typing import Dict, Optional

local_mac_vendors: Dict[str, str] = {}

@asynccontextmanager
async def lifespan(app: FastAPI):
    load_local_mac_vendors()
    yield

app = FastAPI(title="MAC Address Vendor Lookup", version="1.0.0", lifespan=lifespan)

local_mac_vendors: Dict[str, str] = {}

def load_local_mac_vendors():
    """Load MAC vendor data from local file"""
    global local_mac_vendors
    if local_mac_vendors or not os.path.exists("mac_list.txt"):
        return
    
    try:
        with open("mac_list.txt", "r", encoding="utf-8") as file:
            for line in file:
                line = line.strip()
                if line:
                    parts = line.split('\t', 1)
                    if len(parts) == 2:
                        oui = parts[0].strip().upper()
                        vendor = parts[1].strip()
                        local_mac_vendors[oui] = vendor
    except Exception:
        pass

async def lookup_from_github(oui: str) -> Optional[str]:
    """Lookup vendor from GitHub gist"""
    url = "https://gist.githubusercontent.com/aallan/b4bb86db86079509e6159810ae9bd3e4/raw/846ae1b646ab0f4d646af9115e47365f4118e5f6/mac-vendor.txt"
    
    try:
        async with httpx.AsyncClient() as client:
            response = await client.get(url, timeout=10.0)
            response.raise_for_status()
            
            for line in response.text.strip().split('\n'):
                if line.strip():
                    parts = line.split('\t', 1)
                    if len(parts) == 2 and parts[0].strip().upper() == oui:
                        return parts[1].strip()
    except Exception:
        pass
    
    return None

async def lookup_from_macvendors_api(mac_address: str) -> Optional[str]:
    """Lookup vendor from macvendors.com API"""
    try:
        formatted_mac = normalize_mac_for_api(mac_address)
        url = f"https://api.macvendors.com/{formatted_mac}"
        
        async with httpx.AsyncClient() as client:
            response = await client.get(url, timeout=10.0)
            
            if response.status_code == 200:
                content_type = response.headers.get("content-type", "")
                if "application/json" in content_type:
                    return None
                else:
                    return response.text.strip()
    except Exception:
        pass
    
    return None

def normalize_mac_for_api(mac_address: str) -> str:
    """Normalize MAC address for external API (XX-XX-XX format)"""
    clean_mac = re.sub(r'[^a-fA-F0-9]', '', mac_address.upper())
    if len(clean_mac) >= 6:
        return f"{clean_mac[0:2]}-{clean_mac[2:4]}-{clean_mac[4:6]}"
    else:
        raise ValueError("Invalid MAC address format")

def normalize_mac_response(mac_address: str) -> str:
    """Normalize MAC address for response format"""
    clean_mac = re.sub(r'[^a-fA-F0-9]', '', mac_address.upper())
    
    if len(clean_mac) == 6:
        return f"{clean_mac[0:2]}-{clean_mac[2:4]}-{clean_mac[4:6]}"
    elif len(clean_mac) == 12:
        return f"{clean_mac[0:2]}-{clean_mac[2:4]}-{clean_mac[4:6]}-{clean_mac[6:8]}-{clean_mac[8:10]}-{clean_mac[10:12]}"
    else:
        raise ValueError("Invalid MAC address format")

def get_oui(mac_address: str) -> str:
    """Extract OUI (first 6 hex digits) from MAC address"""
    clean_mac = re.sub(r'[^a-fA-F0-9]', '', mac_address.upper())
    if len(clean_mac) >= 6:
        return clean_mac[:6]
    else:
        raise ValueError("MAC address too short")



@app.get("/")
async def root():
    return {"message": "MAC Address Vendor Lookup API"}

@app.get("/lookup/{mac_address}")
async def lookup_vendor(mac_address: str):
    try:
        oui = get_oui(mac_address)
        formatted_mac = normalize_mac_response(mac_address)
        vendor = None
        
        # 1. Try local file first
        if oui in local_mac_vendors:
            vendor = local_mac_vendors[oui]
        
        # 2. Try GitHub gist if not found locally
        if not vendor:
            vendor = await lookup_from_github(oui)
        
        # 3. Try macvendors.com API if still not found
        if not vendor:
            vendor = await lookup_from_macvendors_api(mac_address)
        
        # Default to Unknown if nothing found
        if not vendor:
            vendor = "Unknown"
        
        return {
            "mac_address": formatted_mac,
            "vendor": vendor
        }
        
    except ValueError as e:
        raise HTTPException(status_code=400, detail=str(e))
    except Exception as e:
        raise HTTPException(status_code=500, detail="Internal server error")

if __name__ == "__main__":
    import uvicorn
    uvicorn.run(app, host="0.0.0.0", port=8000)