app.py

from typing import List, Dict, Optional
from datetime import datetime, timedelta
from fastapi import FastAPI, HTTPException, Query, Body, Request
from pydantic import BaseModel, validator
import json
import os

app = FastAPI()

# Data storage (in-memory)
user_data: Dict[str, dict] = {}  # Key: IP address, Value: User entry

# Data storage file
DATA_FILE = "user_data.json"

# --- Data Models ---
class UserEntry(BaseModel):
    ip_address: str
    device_type: str
    timestamp: datetime

    @validator("ip_address")
    def validate_ip_address(cls, value):
        parts = value.split('.')
        if len(parts) != 4:
            raise ValueError("Invalid IP address format")
        for part in parts:
            try:
                num = int(part)
                if not 0 <= num <= 255:
                    raise ValueError("Invalid IP address value")
            except ValueError:
                raise ValueError("Invalid IP address value")
        return value

# --- Helper Functions ---
def load_data():
    """Loads data from the JSON file into the in-memory store."""
    global user_data
    if os.path.exists(DATA_FILE):
        try:
            with open(DATA_FILE, "r") as f:
                data = json.load(f)
                # Convert timestamp strings back to datetime objects
                user_data = {
                    ip: {**entry, "timestamp": datetime.fromisoformat(entry["timestamp"])}
                    for ip, entry in data.items()
                }
        except Exception as e:
            print(f"Error loading data from {DATA_FILE}: {e}")
            # Handle the error gracefully, maybe start with an empty dataset
            user_data = {}

def save_data():
    """Saves the in-memory data to the JSON file."""
    try:
        with open(DATA_FILE, "w") as f:
            # Convert datetime objects to ISO format for JSON serialization
            serializable_data = {
                ip: {**entry, "timestamp": entry["timestamp"].isoformat()}
                for ip, entry in user_data.items()
            }
            json.dump(serializable_data, f, indent=4)
    except Exception as e:
        print(f"Error saving data to {DATA_FILE}: {e}")

def clean_old_data():
    """Deletes data older than 7 days."""
    global user_data
    cutoff_time = datetime.now() - timedelta(days=7)
    ips_to_delete = [ip for ip, entry in user_data.items() if entry["timestamp"] < cutoff_time]
    for ip in ips_to_delete:
        del user_data[ip]
    if ips_to_delete:
        save_data()  # Save changes after deleting old data

# Load data on startup
load_data()

# --- API Endpoints ---
@app.post("/auto_entry/", response_model=UserEntry, status_code=201)
async def create_auto_user_entry(
    request: Request,
    device_type: str = Body(...),
    timestamp: Optional[datetime] = Body(None)
):
    """
    Endpoint to automatically record user entry by extracting the IP address
    from the request and taking device_type and optional timestamp as input.
    """
    try:
        # Automatically extract the client's IP address
        client_ip = request.client.host
        if "x-forwarded-for" in request.headers:
            client_ip = request.headers["x-forwarded-for"].split(",")[0]

        # If timestamp is not provided, use the current time
        if not timestamp:
            timestamp = datetime.now()

        # Create a UserEntry object
        entry_data = UserEntry(
            ip_address=ip_address,
            device_type=device_type,
            timestamp=timestamp
        )

        # Save the entry
        user_data[ip_address] = entry_data.dict()
        save_data()

        return entry_data

    except ValueError as ve:
        raise HTTPException(status_code=400, detail=str(ve))
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Internal server error: {e}")

@app.post("/entry/", response_model=UserEntry, status_code=201)
async def create_user_entry(entry_data: UserEntry):
    """Endpoint to record user entry."""
    try:
        entry_data.timestamp = datetime.now()
        user_data[entry_data.ip_address] = entry_data.dict()
        save_data()
        return entry_data
    except ValueError as ve:
        raise HTTPException(status_code=400, detail=str(ve))
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Internal server error: {e}")

@app.get("/analytics/")
async def get_user_analytics(period: str = Query(..., enum=["last_hour", "last_day", "last_7_day"])):
    """Endpoint to get user analytics."""
    try:
        clean_old_data()  # Clean data before processing

        now = datetime.now()
        if period == "last_hour":
            cutoff = now - timedelta(hours=1)
        elif period == "last_day":
            cutoff = now - timedelta(days=1)
        elif period == "last_7_day":
            cutoff = now - timedelta(days=7)
        else:
            raise HTTPException(status_code=400, detail="Invalid period specified")

        filtered_data = [entry for entry in user_data.values() if entry["timestamp"] >= cutoff]
        unique_users = len(set(entry["ip_address"] for entry in filtered_data))
        device_counts: Dict[str, int] = {}
        for entry in filtered_data:
            device_counts[entry["device_type"]] = device_counts.get(entry["device_type"], 0) + 1

        return {
            "total_unique_users": unique_users,
            "device_type_info": device_counts,
        }
    except HTTPException as he:
        raise he
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Error generating analytics: {e}")

@app.get("/export/", response_model=Dict[str, UserEntry])
async def export_user_data():
    """Endpoint to export all user data in JSON format."""
    try:
        clean_old_data()  # Ensure no old data is exported
        return user_data
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Error exporting data: {e}")

@app.post("/import/")
async def import_user_data(data: Dict[str, dict] = Body(...)):
    """Endpoint to import user data from JSON."""
    try:
        imported_count = 0
        for ip, entry_dict in data.items():
            try:
                # Validate the imported entry
                entry = UserEntry(**entry_dict)
                entry.timestamp = datetime.fromisoformat(entry_dict["timestamp"]) # Ensure timestamp is datetime
                user_data[ip] = entry.dict()
                imported_count += 1
            except Exception as e:
                print(f"Error importing entry for IP {ip}: {e}")  # Log individual import errors

        save_data()
        return {"message": f"Successfully imported {imported_count} user entries."}
    except json.JSONDecodeError:
        raise HTTPException(status_code=400, detail="Invalid JSON format")
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Error importing data: {e}")

# --- Background Task (Optional, for regular cleanup) ---
async def scheduled_cleanup():
    """Periodically clean up old data."""
    while True:
        clean_old_data()
        await asyncio.sleep(60 * 60)  # Clean every hour

# Import asyncio if you use the background task
import asyncio
from fastapi import BackgroundTasks

@app.on_event("startup")
async def startup_event():
    # You can uncomment this to run the background task
    asyncio.create_task(scheduled_cleanup())
    pass

# --- Error Handling (Advanced - using exception handlers) ---
from fastapi import Request
from fastapi.responses import JSONResponse

@app.exception_handler(HTTPException)
async def http_exception_handler(request: Request, exc: HTTPException):
    return JSONResponse(
        status_code=exc.status_code,
        content={"message": exc.detail},
    )

@app.exception_handler(Exception)
async def general_exception_handler(request: Request, exc: Exception):
    return JSONResponse(
        status_code=500,
        content={"message": f"An unexpected error occurred: {exc}"},
    )

if __name__ == "__main__":
    import uvicorn
    uvicorn.run(app, host="0.0.0.0", port=8083, debug=True)