alternative-backend-service/meetings/models.py

import uuid
from django.db import models
from django.conf import settings
from django.utils import timezone
from cryptography.fernet import Fernet
from cryptography.hazmat.primitives import hashes
from cryptography.hazmat.primitives.kdf.pbkdf2 import PBKDF2HMAC
import base64
import os

class EncryptionManager:
    def __init__(self):
        self.fernet = self._get_fernet()
    
    def _get_fernet_key(self):
        key = getattr(settings, 'ENCRYPTION_KEY', None) or os.environ.get('ENCRYPTION_KEY')
        if not key:
            key = Fernet.generate_key().decode()
        key = key.encode()
        return key
    
    def _get_fernet(self):
        key = self._get_fernet_key()
        return Fernet(key)
    
    def encrypt_value(self, value):
        if value is None or value == "":
            return value
        encrypted_value = self.fernet.encrypt(value.encode())
        return base64.urlsafe_b64encode(encrypted_value).decode()
    
    def decrypt_value(self, encrypted_value):
        if encrypted_value is None or encrypted_value == "":
            return encrypted_value
        try:
            encrypted_bytes = base64.urlsafe_b64decode(encrypted_value.encode())
            decrypted_value = self.fernet.decrypt(encrypted_bytes)
            return decrypted_value.decode()
        except Exception as e:
            print(f"Decryption error: {e}")
            return encrypted_value

encryption_manager = EncryptionManager()

class EncryptedCharField(models.CharField):
    def from_db_value(self, value, expression, connection):
        if value is None:
            return value
        return encryption_manager.decrypt_value(value)
    
    def get_prep_value(self, value):
        if value is None:
            return value
        return encryption_manager.encrypt_value(value)

class EncryptedEmailField(EncryptedCharField):
    def __init__(self, *args, **kwargs):
        kwargs['max_length'] = 254
        super().__init__(*args, **kwargs)
        
    def from_db_value(self, value, expression, connection):
        if value is None:
            return value
        return encryption_manager.decrypt_value(value)
    
    def get_prep_value(self, value):
        if value is None:
            return value
        return encryption_manager.encrypt_value(value)

class EncryptedTextField(models.TextField):
    def from_db_value(self, value, expression, connection):
        if value is None:
            return value
        return encryption_manager.decrypt_value(value)
    
    def get_prep_value(self, value):
        if value is None:
            return value
        return encryption_manager.encrypt_value(value)

class AdminWeeklyAvailability(models.Model):
    DAYS_OF_WEEK = [
        (0, 'Monday'),
        (1, 'Tuesday'),
        (2, 'Wednesday'),
        (3, 'Thursday'),
        (4, 'Friday'),
        (5, 'Saturday'),
        (6, 'Sunday'),
    ]
    
    TIME_SLOT_CHOICES = [
        ('morning', 'Morning (9AM - 12PM)'),
        ('afternoon', 'Afternoon (1PM - 5PM)'),
        ('evening', 'Evening (6PM - 9PM)'),
    ]
    
    availability_schedule = models.JSONField(
        default=dict,
        help_text="Dictionary with days as keys and lists of time slots as values"
    )
    created_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)
    
    class Meta:
        verbose_name = 'Admin Weekly Availability'
        verbose_name_plural = 'Admin Weekly Availability'
    
    def set_availability(self, day, time_slots):
        if not self.availability_schedule:
            self.availability_schedule = {}
        
        if day not in [str(d[0]) for d in self.DAYS_OF_WEEK]:
            raise ValueError(f"Invalid day: {day}")
        
        valid_slots = [slot[0] for slot in self.TIME_SLOT_CHOICES]
        for slot in time_slots:
            if slot not in valid_slots:
                raise ValueError(f"Invalid time slot: {slot}")
        
        self.availability_schedule[str(day)] = time_slots
    
    def get_availability_for_day(self, day):
        return self.availability_schedule.get(str(day), [])
    
    def is_available(self, day, time_slot):
        return time_slot in self.get_availability_for_day(day)
    
    def get_all_available_slots(self):
        available_slots = []
        for day_num, time_slots in self.availability_schedule.items():
            day_name = dict(self.DAYS_OF_WEEK).get(int(day_num))
            for time_slot in time_slots:
                time_display = dict(self.TIME_SLOT_CHOICES).get(time_slot)
                available_slots.append({
                    'day_num': int(day_num),
                    'day_name': day_name,
                    'time_slot': time_slot,
                    'time_display': time_display
                })
        return available_slots
    
    def clear_availability(self, day=None):
        if day is None:
            self.availability_schedule = {}
        else:
            day_str = str(day)
            if day_str in self.availability_schedule:
                del self.availability_schedule[day_str]
    
    def __str__(self):
        if not self.availability_schedule:
            return "No availability set"
        
        display_strings = []
        for day_num, time_slots in sorted(self.availability_schedule.items()):
            day_name = dict(self.DAYS_OF_WEEK).get(int(day_num))
            slot_displays = [dict(self.TIME_SLOT_CHOICES).get(slot) for slot in time_slots]
            display_strings.append(f"{day_name}: {', '.join(slot_displays)}")
        
        return " | ".join(display_strings)

class AppointmentRequest(models.Model):
    STATUS_CHOICES = [
        ('pending_review', 'Pending Review'),
        ('scheduled', 'Scheduled'),
        ('rejected', 'Rejected'),
        ('completed', 'Completed'),
        ('cancelled', 'Cancelled'),
    ]
    
    TIME_SLOT_CHOICES = [
        ('morning', 'Morning (9AM - 12PM)'),
        ('afternoon', 'Afternoon (1PM - 5PM)'),
        ('evening', 'Evening (6PM - 9PM)'),
    ]

    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    first_name = EncryptedCharField(max_length=100)
    last_name = EncryptedCharField(max_length=100)
    email = EncryptedEmailField()
    phone = EncryptedCharField(max_length=20, blank=True)
    reason = EncryptedTextField(blank=True)
    
    preferred_dates = models.JSONField(
        help_text="List of preferred dates (YYYY-MM-DD format)"
    )
    preferred_time_slots = models.JSONField(
        help_text="List of preferred time slots (morning/afternoon/evening)"
    )
    
    status = models.CharField(
        max_length=20, 
        choices=STATUS_CHOICES, 
        default='pending_review'
    )
    
    scheduled_datetime = models.DateTimeField(null=True, blank=True)
    scheduled_duration = models.PositiveIntegerField(
        default=60,
        help_text="Duration in minutes"
    )
    rejection_reason = EncryptedTextField(blank=True)
    
    jitsi_meet_url = models.URLField(blank=True, help_text="Jitsi Meet URL for the video session")
    jitsi_room_id = models.CharField(max_length=100, unique=True, blank=True, help_text="Jitsi room ID")
    
    created_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)
    
    class Meta:
        ordering = ['-created_at']
        verbose_name = 'Appointment Request'
        verbose_name_plural = 'Appointment Requests'
        indexes = [
            models.Index(fields=['status', 'scheduled_datetime']),
            models.Index(fields=['email', 'created_at']),
        ]

    @property
    def full_name(self):
        return f"{self.first_name} {self.last_name}"

    @property
    def formatted_created_at(self):
        return self.created_at.strftime("%B %d, %Y at %I:%M %p")

    @property
    def formatted_scheduled_datetime(self):
        if self.scheduled_datetime:
            return self.scheduled_datetime.strftime("%B %d, %Y at %I:%M %p")
        return None

    @property
    def has_jitsi_meeting(self):
        return bool(self.jitsi_meet_url and self.jitsi_room_id)

    @property
    def meeting_in_future(self):
        if not self.scheduled_datetime:
            return False
        return self.scheduled_datetime > timezone.now()

    @property
    def meeting_duration_display(self):
        hours = self.scheduled_duration // 60
        minutes = self.scheduled_duration % 60
        if hours > 0:
            return f"{hours}h {minutes}m"
        return f"{minutes}m"

    def get_preferred_dates_display(self):
        try:
            dates = [timezone.datetime.strptime(date, '%Y-%m-%d').strftime('%b %d, %Y') 
                    for date in self.preferred_dates]
            return ', '.join(dates)
        except:
            return ', '.join(self.preferred_dates)

    def get_preferred_time_slots_display(self):
        slot_display = {
            'morning': 'Morning',
            'afternoon': 'Afternoon', 
            'evening': 'Evening'
        }
        return ', '.join([slot_display.get(slot, slot) for slot in self.preferred_time_slots])

    def generate_jitsi_room_id(self):
        if not self.jitsi_room_id:
            self.jitsi_room_id = f"therapy_session_{self.id.hex[:16]}"
        return self.jitsi_room_id

    def create_jitsi_meeting(self):
        if not self.jitsi_room_id:
            self.generate_jitsi_room_id()
        
        jitsi_base_url = getattr(settings, 'JITSI_BASE_URL', 'https://meet.jit.si')
        self.jitsi_meet_url = f"{jitsi_base_url}/{self.jitsi_room_id}"
        return self.jitsi_meet_url

    def get_jitsi_join_info(self):
        if not self.has_jitsi_meeting:
            return None
        
        return {
            'meeting_url': self.jitsi_meet_url,
            'room_id': self.jitsi_room_id,
            'scheduled_time': self.formatted_scheduled_datetime,
            'duration': self.meeting_duration_display,
            'join_instructions': 'Click the meeting URL to join the video session. No password required.'
        }

    def schedule_appointment(self, datetime_obj, duration=60, commit=True):
        self.status = 'scheduled'
        self.scheduled_datetime = datetime_obj
        self.scheduled_duration = duration
        self.rejection_reason = ''
        
        self.create_jitsi_meeting()
        
        if commit:
            self.save()

    def reject_appointment(self, reason='', commit=True):
        self.status = 'rejected'
        self.rejection_reason = reason
        self.scheduled_datetime = None
        self.jitsi_meet_url = ''
        self.jitsi_room_id = ''
        if commit:
            self.save()

    def cancel_appointment(self, reason='', commit=True):
        self.status = 'cancelled'
        self.rejection_reason = reason
        if commit:
            self.save()

    def complete_appointment(self, commit=True):
        self.status = 'completed'
        if commit:
            self.save()

    def can_join_meeting(self):
        if not self.scheduled_datetime or not self.has_jitsi_meeting:
            return False
        
        if self.status != 'scheduled':
            return False
        
        now = timezone.now()
        meeting_start = self.scheduled_datetime
        meeting_end = meeting_start + timezone.timedelta(minutes=self.scheduled_duration + 15)  # 15 min buffer
        
        return meeting_start - timezone.timedelta(minutes=10) <= now <= meeting_end

    def get_meeting_status(self):
        if not self.scheduled_datetime:
            return "Not scheduled"
        
        now = timezone.now()
        meeting_start = self.scheduled_datetime
        
        if now < meeting_start - timezone.timedelta(minutes=10):
            return "Scheduled"
        elif self.can_join_meeting():
            return "Ready to join"
        elif now > meeting_start + timezone.timedelta(minutes=self.scheduled_duration):
            return "Completed"
        else:
            return "Ended"

    def get_available_time_slots_for_date(self, date_str):
        try:
            from datetime import datetime
            date_obj = datetime.strptime(date_str, '%Y-%m-%d').date()
            day_of_week = date_obj.weekday()
            
            availability = AdminWeeklyAvailability.objects.first()
            if not availability:
                return []
            
            return availability.get_availability_for_day(day_of_week)
        except Exception as e:
            print(f"Error getting available slots: {e}")
            return []

    def are_preferences_available(self):
        availability = AdminWeeklyAvailability.objects.first()
        if not availability:
            return False
        
        for date_str in self.preferred_dates:
            try:
                from datetime import datetime
                date_obj = datetime.strptime(date_str, '%Y-%m-%d').date()
                day_of_week = date_obj.weekday()
                
                available_slots = availability.get_availability_for_day(day_of_week)
                if any(slot in available_slots for slot in self.preferred_time_slots):
                    return True
            except Exception as e:
                print(f"Error checking availability for {date_str}: {e}")
                continue
        
        return False

    def get_matching_availability(self):
        availability = AdminWeeklyAvailability.objects.first()
        if not availability:
            return []
        
        matching_slots = []
        for date_str in self.preferred_dates:
            try:
                from datetime import datetime
                date_obj = datetime.strptime(date_str, '%Y-%m-%d').date()
                day_of_week = date_obj.weekday()
                day_name = dict(AdminWeeklyAvailability.DAYS_OF_WEEK).get(day_of_week)
                
                available_slots = availability.get_availability_for_day(day_of_week)
                matching_time_slots = [slot for slot in self.preferred_time_slots if slot in available_slots]
                
                if matching_time_slots:
                    matching_slots.append({
                        'date': date_str,
                        'day_name': day_name,
                        'available_slots': matching_time_slots,
                        'date_obj': date_obj
                    })
            except Exception as e:
                print(f"Error processing {date_str}: {e}")
                continue
        
        return matching_slots

    def __str__(self):
        return f"{self.full_name} - {self.get_status_display()} - {self.created_at.strftime('%Y-%m-%d')}"


def get_admin_availability():
    availability, created = AdminWeeklyAvailability.objects.get_or_create(
        id=1
    )
    return availability

def set_admin_availability(availability_dict):
    availability = get_admin_availability()
    
    for day, time_slots in availability_dict.items():
        availability.set_availability(day, time_slots)
    
    availability.save()
    return availability

def get_available_slots_for_week():
    availability = get_admin_availability()
    return availability.get_all_available_slots()

def check_date_availability(date_str):
    try:
        from datetime import datetime
        date_obj = datetime.strptime(date_str, '%Y-%m-%d').date()
        day_of_week = date_obj.weekday()
        
        availability = get_admin_availability()
        return availability.get_availability_for_day(day_of_week)
    except Exception as e:
        print(f"Error checking date availability: {e}")
        return []