Add event schema models and corresponding test cases

Introduce Pydantic models for event creation, updates, and responses, including validation for fields such as timezone, event date, and RSVP deadline. Add comprehensive pytest test cases to ensure correct behavior and data validation. This provides a robust foundation for event-related functionalities.

backend/app/schemas/events.py

@@ -0,0 +1,81 @@
+from datetime import datetime, time
+from typing import Dict, Optional, List, Union
+from uuid import UUID
+from pydantic import BaseModel, Field, field_validator
+from zoneinfo import ZoneInfo
+
+
+class EventBase(BaseModel):
+    title: str = Field(..., min_length=1, max_length=200)
+    description: Optional[str] = None
+    location_name: Optional[str] = None
+    location_address: Optional[str] = None
+    location_url: Optional[str] = None
+    event_date: datetime
+    event_start_time: Optional[time] = None
+    event_end_time: Optional[time] = None
+    timezone: str
+    rsvp_deadline: Optional[datetime] = None
+    is_public: bool = False
+    access_code: Optional[str] = None
+    theme_id: Optional[UUID] = None
+    custom_theme_settings: Optional[Dict] = None
+    additional_info: Optional[Dict] = None
+    is_active: bool = True
+    rsvp_enabled: bool = True
+    gift_registry_enabled: bool = True
+    updates_enabled: bool = True
+    max_guests_per_invitation: Optional[int] = Field(None, ge=1)
+    contact_email: Optional[str] = None
+    contact_phone: Optional[str] = None
+
+    @field_validator('timezone')
+    def validate_timezone(cls, v):
+        try:
+            ZoneInfo(v)
+            return v
+        except Exception:
+            raise ValueError("Invalid timezone")
+
+    @field_validator('event_date')
+    def validate_event_date(cls, v):
+        if v < datetime.now(ZoneInfo('UTC')):
+            raise ValueError("Event date cannot be in the past")
+        return v
+
+    @field_validator('rsvp_deadline')
+    def validate_rsvp_deadline(cls, v, values):
+        if v and 'event_date' in values.data:
+            if v > values.data['event_date']:
+                raise ValueError("RSVP deadline must be before event date")
+        return v
+
+
+class EventCreate(EventBase):
+    slug: str = Field(..., min_length=1, pattern="^[a-z0-9-]+$")
+
+
+class EventUpdate(EventBase):
+    title: Optional[str] = None
+    event_date: Optional[datetime] = None
+    timezone: Optional[str] = None
+    slug: Optional[str] = Field(None, min_length=1, pattern="^[a-z0-9-]+$")
+
+
+class EventInDBBase(EventBase):
+    id: UUID
+    created_by: UUID
+    created_at: datetime
+    updated_at: datetime
+    slug: str
+
+    class Config:
+        from_attributes = True
+
+
+class EventResponse(EventInDBBase):
+    pass
+
+
+class Event(EventInDBBase):
+    pass