Python Data Structures & OOP

from enum import Enum class Priority(Enum): LOW = 1 MEDIUM = 2 HIGH = 3 CRITICAL = 4 class TaskStatus(Enum): PENDING = "pending" IN_PROGRESS = "in_progress" COMPLETED = "completed" ARCHIVED = "archived"

from dataclasses import dataclass from datetime import datetime import uuid @dataclass class Comment: author: str content: str timestamp: datetime comment_id: str = None def __post_init__(self): if self.comment_id is None: self.comment_id = str(uuid.uuid4())[:8]

class Task: def __init__(self, title: str, description: str = "", priority: Priority = Priority.MEDIUM): self.id = str(uuid.uuid4())[:8] self.title = title self.description = description self.priority = priority self.status = TaskStatus.PENDING self.created_at = datetime.now() self.updated_at = datetime.now() self.completed_at = None self.tags = set() self.comments = [] self.assigned_to = None self.estimated_hours = None def update_status(self, status: TaskStatus): self.status = status self.updated_at = datetime.now() if status == TaskStatus.COMPLETED: self.completed_at = datetime.now() def add_tag(self, tag: str): self.tags.add(tag.lower()) self.updated_at = datetime.now() def add_comment(self, author: str, content: str): self.comments.append(Comment(author, content, datetime.now())) def assign_to(self, user_id: str): self.assigned_to = user_id self.updated_at = datetime.now() @property def is_overdue(self) -> bool: if self.status == TaskStatus.COMPLETED: return False if hasattr(self, 'due_date') and self.due_date: return datetime.now() > self.due_date return False def __str__(self): symbols = {TaskStatus.COMPLETED: '✅', TaskStatus.IN_PROGRESS: '⚡', TaskStatus.PENDING: '⏳'} symbol = symbols.get(self.status, '📌') return f"{symbol} [{self.priority.name}] {self.title}"

class Project: def __init__(self, name: str, description: str = ""): self.id = str(uuid.uuid4())[:8] self.name = name self.description = description self.tasks = {} self.created_at = datetime.now() self.updated_at = datetime.now() self.owner = None self.members = set() def add_task(self, task: Task) -> str: self.tasks[task.id] = task self.updated_at = datetime.now() return task.id def get_tasks_by_priority(self, priority: Priority): return [t for t in self.tasks.values() if t.priority == priority] def get_tasks_by_status(self, status: TaskStatus): return [t for t in self.tasks.values() if t.status == status] def get_tasks_by_tag(self, tag: str): tag = tag.lower() return [t for t in self.tasks.values() if tag in t.tags] def add_member(self, user_id: str): self.members.add(user_id) @property def progress(self): total = len(self.tasks) if total == 0: return {'percentage': 0} completed = len(self.get_tasks_by_status(TaskStatus.COMPLETED)) return {'completed': completed, 'percentage': (completed/total)*100} def __str__(self): return f"📁 {self.name} ({len(self.tasks)} tasks) - {self.progress['percentage']:.1f}% complete"

class User: def __init__(self, username: str, email: str, full_name: str = ""): self.id = str(uuid.uuid4())[:8] self.username = username self.email = email self.full_name = full_name or username self.created_at = datetime.now() self.last_active = datetime.now() self.projects = {} self.notifications = [] def create_project(self, name: str, description: str = "") -> Project: project = Project(name, description) project.owner = self.id project.add_member(self.id) self.projects[project.id] = project return project def join_project(self, project: Project): self.projects[project.id] = project project.add_member(self.id) self.last_active = datetime.now() @property def is_active(self) -> bool: return (datetime.now() - self.last_active).total_seconds() < 300 def __str__(self): status = "🟢" if self.is_active else "⚪" return f"{status} {self.full_name} (@{self.username})"

class TaskManager: def __init__(self, name: str = "Task Manager"): self.name = name self.users = {} self.projects = {} self.tasks = {} self.activity_log = [] def create_user(self, username: str, email: str, full_name: str = "") -> User: if username in [u.username for u in self.users.values()]: raise ValueError(f"User {username} exists") user = User(username, email, full_name) self.users[user.id] = user self._log(f"User created: {username}") return user def register_project(self, project: Project): self.projects[project.id] = project for task in project.tasks.values(): self.tasks[task.id] = task self._log(f"Project registered: {project.name}") def search_tasks(self, query: str): query = query.lower() return [t for t in self.tasks.values() if query in t.title.lower() or query in [tag for tag in t.tags]] def get_statistics(self): total_tasks = len(self.tasks) completed = len([t for t in self.tasks.values() if t.status == TaskStatus.COMPLETED]) active_users = len([u for u in self.users.values() if u.is_active]) return { 'total_users': len(self.users), 'active_users': active_users, 'total_projects': len(self.projects), 'total_tasks': total_tasks, 'completed_tasks': completed, 'completion_rate': (completed/total_tasks*100) if total_tasks else 0 } def _log(self, message: str): self.activity_log.append(f"[{datetime.now().strftime('%H:%M')}] {message}") def __str__(self): s = self.get_statistics() return f"{self.name} · {s['total_users']} users · {s['total_projects']} projects · {s['total_tasks']} tasks"