from datetime import datetime, time, timedelta from django.utils import timezone from django.db.models import Q from .models import Appointment, BusinessHours, StaffMember def get_available_slots(date, service, staff=None, duration=None): """ Get available time slots for a given date, service, and optional staff member. Args: date (date): The date to check for availability service (Service): The service to book staff (StaffMember, optional): Specific staff member to check. If None, checks all staff. duration (timedelta, optional): Duration of the appointment. If None, uses service duration. Returns: list: List of available time slots as (start_time, end_time) tuples """ # Use service duration if no duration provided duration = duration or service.duration # Get the day of the week (0=Monday, 6=Sunday) day_of_week = date.weekday() day_name = [ 'monday', 'tuesday', 'wednesday', 'thursday', 'friday', 'saturday', 'sunday' ][day_of_week] try: # Get business hours for this day business_hours = BusinessHours.objects.get(day=day_name) # If business is closed, return empty list if not business_hours.is_open: return [] # Get business open and close times open_time = business_hours.open_time close_time = business_hours.close_time except BusinessHours.DoesNotExist: # If no business hours set for this day, assume 24/7 availability open_time = time(0, 0) close_time = time(23, 59, 59) # Convert to datetime for easier manipulation start_datetime = datetime.combine(date, open_time) end_datetime = datetime.combine(date, close_time) # If close time is before open time (overnight), add a day to close time if close_time <= open_time: end_datetime += timedelta(days=1) # Get all staff members who provide this service if staff: staff_members = [staff] else: staff_members = StaffMember.objects.filter( services=service, is_active=True ) # If no staff members provide this service, return empty list if not staff_members.exists(): return [] # Get all existing appointments for the given date and staff members appointments = Appointment.objects.filter( staff_member__in=staff_members, start_time__date=date, status__in=['pending', 'confirmed'] ) # Generate time slots time_slots = [] current_time = start_datetime while current_time + duration <= end_datetime: slot_end = current_time + duration # Check if this time slot is available for any staff member slot_available = False for staff_member in staff_members: # Check for overlapping appointments for this staff member overlapping = appointments.filter( staff_member=staff_member, start_time__lt=slot_end, end_time__gt=current_time ).exists() if not overlapping: slot_available = True break if slot_available: time_slots.append((current_time, slot_end)) # Move to next time slot (15-minute intervals) current_time += timedelta(minutes=15) return time_slots def is_time_slot_available(staff_member, start_time, end_time, exclude_appointment_id=None): """ Check if a specific time slot is available for a staff member. Args: staff_member (StaffMember): The staff member to check start_time (datetime): Start time of the desired slot end_time (datetime): End time of the desired slot exclude_appointment_id (int, optional): ID of an appointment to exclude (for updates) Returns: bool: True if the time slot is available, False otherwise """ # Check for overlapping appointments overlapping = Appointment.objects.filter( staff_member=staff_member, start_time__lt=end_time, end_time__gt=start_time, status__in=['pending', 'confirmed'] ) # Exclude the current appointment when updating if exclude_appointment_id: overlapping = overlapping.exclude(pk=exclude_appointment_id) return not overlapping.exists() def get_staff_availability(staff_member, start_date, end_date): """ Get a staff member's availability for a date range. Args: staff_member (StaffMember): The staff member to check start_date (date): Start date of the range end_date (date): End date of the range (inclusive) Returns: dict: Dictionary with date keys and list of available time slots """ availability = {} current_date = start_date while current_date <= end_date: # Get business hours for this day day_of_week = current_date.weekday() day_name = [ 'monday', 'tuesday', 'wednesday', 'thursday', 'friday', 'saturday', 'sunday' ][day_of_week] try: business_hours = BusinessHours.objects.get(day=day_name) if business_hours.is_open: # Get appointments for this day appointments = Appointment.objects.filter( staff_member=staff_member, start_time__date=current_date, status__in=['pending', 'confirmed'] ).order_by('start_time') # Generate available time slots available_slots = [] # Start with the full business day open_time = datetime.combine(current_date, business_hours.open_time) close_time = datetime.combine(current_date, business_hours.close_time) # If close time is before open time (overnight), add a day to close time if business_hours.close_time <= business_hours.open_time: close_time += timedelta(days=1) # If no appointments, the whole day is available if not appointments.exists(): available_slots.append({ 'start': open_time, 'end': close_time }) else: # Add time before first appointment first_appointment = appointments.first() if first_appointment.start_time > open_time: available_slots.append({ 'start': open_time, 'end': first_appointment.start_time }) # Add time between appointments for i in range(len(appointments) - 1): current_end = appointments[i].end_time next_start = appointments[i + 1].start_time if current_end < next_start: available_slots.append({ 'start': current_end, 'end': next_start }) # Add time after last appointment last_appointment = appointments.last() if last_appointment.end_time < close_time: available_slots.append({ 'start': last_appointment.end_time, 'end': close_time }) availability[current_date.isoformat()] = available_slots else: availability[current_date.isoformat()] = [] except BusinessHours.DoesNotExist: # If no business hours set, assume 24/7 availability availability[current_date.isoformat()] = [{ 'start': datetime.combine(current_date, time(0, 0)), 'end': datetime.combine(current_date, time(23, 59, 59)) }] current_date += timedelta(days=1) return availability