from fastapi import FastAPI, HTTPException
from fastapi.middleware.cors import CORSMiddleware
from pydantic import BaseModel
import subprocess
import shlex

app = FastAPI()

# Add CORS middleware
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],  # Allows all origins
    allow_credentials=True,
    allow_methods=["*"],  # Allows all methods
    allow_headers=["*"],  # Allows all headers
)

ALLOWED_COMMANDS = {
    'ls', 'cd', 'pwd', 'echo', 'cat', 'grep', 'find', 'touch', 'mkdir', 'rm', 'cp', 'mv'
}

class Command(BaseModel):
    command: str

@app.post("/execute")
async def execute_command(command: Command):
    try:
        # Parse the command to get the base command
        base_command = shlex.split(command.command)[0]
        
        # Check if the base command is allowed
        if base_command not in ALLOWED_COMMANDS:
            raise HTTPException(status_code=403, detail=f"Command '{base_command}' is not allowed")

        # Execute the command in a controlled environment
        result = subprocess.run(command.command, shell=True, capture_output=True, text=True, timeout=5)
        return {
            "output": result.stdout,
            "error": result.stderr,
            "returncode": result.returncode
        }
    except subprocess.TimeoutExpired:
        raise HTTPException(status_code=408, detail="Command execution timed out")
    except Exception as e:
        raise HTTPException(status_code=500, detail=str(e))

@app.get("/")
async def root():
    return {"message": "Welcome to the Linux Practice Tool API"}