from datetime import datetime
from enum import Enum
from typing import Optional

from pydantic import BaseModel, ConfigDict


class TaskPriority(str, Enum):
    """
    Enum for task priority levels
    """
    LOW = "low"
    MEDIUM = "medium"
    HIGH = "high"

class TaskStatus(str, Enum):
    """
    Enum for task status
    """
    TODO = "todo"
    IN_PROGRESS = "in_progress"
    DONE = "done"

class TaskBase(BaseModel):
    """
    Base task schema with shared attributes
    """
    title: str
    description: Optional[str] = None
    status: TaskStatus = TaskStatus.TODO
    priority: TaskPriority = TaskPriority.MEDIUM
    due_date: Optional[datetime] = None

class TaskCreate(TaskBase):
    """
    Schema for task creation
    """
    pass

class TaskUpdate(BaseModel):
    """
    Schema for task updates
    """
    title: Optional[str] = None
    description: Optional[str] = None
    status: Optional[TaskStatus] = None
    priority: Optional[TaskPriority] = None
    due_date: Optional[datetime] = None
    is_deleted: Optional[bool] = None

class TaskInDBBase(TaskBase):
    """
    Base schema for tasks in DB with id and timestamps
    """
    id: int
    user_id: int
    created_at: datetime
    updated_at: datetime
    is_deleted: bool = False

    model_config = ConfigDict(from_attributes=True)

class Task(TaskInDBBase):
    """
    Schema for returning task information
    """
    pass