from datetime import timedelta
from fastapi import APIRouter, Depends, HTTPException, status
from fastapi.security import OAuth2PasswordRequestForm
from sqlalchemy.orm import Session
from pydantic import BaseModel, EmailStr
from backend.database import get_db, User
from backend.auth import (
    verify_password, get_password_hash, create_access_token, 
    create_refresh_token, decode_token, get_current_user
)

router = APIRouter()


class RegisterRequest(BaseModel):
    email: EmailStr
    password: str


class LoginResponse(BaseModel):
    access_token: str
    refresh_token: str
    token_type: str = "bearer"
    user: dict


class TokenRefreshRequest(BaseModel):
    refresh_token: str


class UserResponse(BaseModel):
    id: str
    email: str
    is_active: bool
    created_at: str


@router.post("/register", response_model=UserResponse)
async def register(request: RegisterRequest, db: Session = Depends(get_db)):
    existing = db.query(User).filter(User.email == request.email).first()
    if existing:
        raise HTTPException(status_code=400, detail="Email already registered")
    
    user = User(
        email=request.email,
        hashed_password=get_password_hash(request.password),
        is_active=True
    )
    db.add(user)
    db.commit()
    db.refresh(user)
    
    return UserResponse(
        id=user.id,
        email=user.email,
        is_active=user.is_active,
        created_at=user.created_at.isoformat()
    )


@router.post("/login", response_model=LoginResponse)
async def login(form_data: OAuth2PasswordRequestForm = Depends(), db: Session = Depends(get_db)):
    user = db.query(User).filter(User.email == form_data.username).first()
    if not user or not verify_password(form_data.password, user.hashed_password):
        raise HTTPException(status_code=401, detail="Invalid credentials")
    
    if not user.is_active:
        raise HTTPException(status_code=403, detail="User account is disabled")
    
    access_token = create_access_token({"sub": user.id})
    refresh_token = create_refresh_token({"sub": user.id})
    
    return LoginResponse(
        access_token=access_token,
        refresh_token=refresh_token,
        user={"id": user.id, "email": user.email}
    )


@router.post("/refresh")
async def refresh_token(request: TokenRefreshRequest, db: Session = Depends(get_db)):
    payload = decode_token(request.refresh_token)
    if payload.get("type") != "refresh":
        raise HTTPException(status_code=401, detail="Invalid token type")
    
    user_id = payload.get("sub")
    user = db.query(User).filter(User.id == user_id).first()
    if not user or not user.is_active:
        raise HTTPException(status_code=401, detail="User not found")
    
    access_token = create_access_token({"sub": user.id})
    return {"access_token": access_token, "token_type": "bearer"}


@router.get("/me", response_model=UserResponse)
async def get_me(current_user: User = Depends(get_current_user)):
    return UserResponse(
        id=current_user.id,
        email=current_user.email,
        is_active=current_user.is_active,
        created_at=current_user.created_at.isoformat()
    )


@router.post("/logout")
async def logout():
    return {"message": "Successfully logged out"}