"""
📧📅 Google Integration for Olivia
Provides Gmail and Calendar access for the household manager persona.

SETUP REQUIRED:
1. Go to https://console.cloud.google.com/
2. Create a new project (or use existing)
3. Enable Gmail API and Google Calendar API
4. Create OAuth 2.0 credentials (Desktop app type)
5. Download credentials.json and place in this directory
6. Run this file directly to authenticate: python google_services.py
"""

import os
import pickle
import datetime
from pathlib import Path

# Google API imports
try:
    from google.auth.transport.requests import Request
    from google.oauth2.credentials import Credentials
    from google_auth_oauthlib.flow import InstalledAppFlow
    from googleapiclient.discovery import build
    from googleapiclient.errors import HttpError
    GOOGLE_AVAILABLE = True
except ImportError:
    GOOGLE_AVAILABLE = False
    print("⚠️ Google API libraries not installed. Run: pip install google-api-python-client google-auth-httplib2 google-auth-oauthlib")

# Scopes for Gmail and Calendar
SCOPES = [
    'https://www.googleapis.com/auth/gmail.readonly',
    'https://www.googleapis.com/auth/gmail.send',
    'https://www.googleapis.com/auth/calendar.readonly',
    'https://www.googleapis.com/auth/calendar.events',
]

# Paths
SCRIPT_DIR = Path(__file__).parent
CREDENTIALS_FILE = SCRIPT_DIR / 'credentials.json'
TOKEN_FILE = SCRIPT_DIR / 'token.pickle'


def get_google_credentials():
    """Get or refresh Google OAuth credentials."""
    if not GOOGLE_AVAILABLE:
        return None
    
    creds = None
    
    # Load existing token
    if TOKEN_FILE.exists():
        with open(TOKEN_FILE, 'rb') as token:
            creds = pickle.load(token)
    
    # Refresh or get new credentials
    if not creds or not creds.valid:
        if creds and creds.expired and creds.refresh_token:
            creds.refresh(Request())
        else:
            if not CREDENTIALS_FILE.exists():
                print(f"⚠️ Missing {CREDENTIALS_FILE}")
                print("   Download from Google Cloud Console → APIs & Services → Credentials")
                return None
            
            flow = InstalledAppFlow.from_client_secrets_file(str(CREDENTIALS_FILE), SCOPES)
            creds = flow.run_local_server(port=0)
        
        # Save token for future use
        with open(TOKEN_FILE, 'wb') as token:
            pickle.dump(creds, token)
    
    return creds


class GmailService:
    """Gmail integration for Olivia."""
    
    def __init__(self):
        self.service = None
        self._connect()
    
    def _connect(self):
        """Connect to Gmail API."""
        creds = get_google_credentials()
        if creds:
            try:
                self.service = build('gmail', 'v1', credentials=creds)
            except Exception as e:
                print(f"⚠️ Gmail connection failed: {e}")
    
    def get_unread_count(self):
        """Get count of unread emails."""
        if not self.service:
            return None
        try:
            results = self.service.users().messages().list(
                userId='me', q='is:unread', maxResults=1
            ).execute()
            return results.get('resultSizeEstimate', 0)
        except HttpError as e:
            print(f"⚠️ Gmail error: {e}")
            return None
    
    def get_recent_emails(self, max_results=5):
        """Get recent email summaries."""
        if not self.service:
            return []
        
        try:
            results = self.service.users().messages().list(
                userId='me', maxResults=max_results
            ).execute()
            
            messages = results.get('messages', [])
            emails = []
            
            for msg in messages:
                msg_data = self.service.users().messages().get(
                    userId='me', id=msg['id'], format='metadata',
                    metadataHeaders=['From', 'Subject', 'Date']
                ).execute()
                
                headers = {h['name']: h['value'] for h in msg_data.get('payload', {}).get('headers', [])}
                emails.append({
                    'id': msg['id'],
                    'from': headers.get('From', 'Unknown'),
                    'subject': headers.get('Subject', '(no subject)'),
                    'date': headers.get('Date', ''),
                    'snippet': msg_data.get('snippet', '')[:100],
                    'unread': 'UNREAD' in msg_data.get('labelIds', [])
                })
            
            return emails
        except HttpError as e:
            print(f"⚠️ Gmail error: {e}")
            return []
    
    def get_email_summary(self):
        """Get a natural language summary for Olivia to speak."""
        unread = self.get_unread_count()
        if unread is None:
            return "I couldn't access your Gmail right now."
        
        if unread == 0:
            return "Your inbox is all clear - no unread emails!"
        
        recent = self.get_recent_emails(3)
        unread_emails = [e for e in recent if e.get('unread')]
        
        if unread == 1:
            summary = f"You have 1 unread email"
        else:
            summary = f"You have {unread} unread emails"
        
        if unread_emails:
            first = unread_emails[0]
            sender = first['from'].split('<')[0].strip()
            summary += f". The most recent is from {sender} about '{first['subject'][:50]}'"
        
        return summary + "."


class CalendarService:
    """Google Calendar integration for Olivia."""
    
    def __init__(self):
        self.service = None
        self._connect()
    
    def _connect(self):
        """Connect to Calendar API."""
        creds = get_google_credentials()
        if creds:
            try:
                self.service = build('calendar', 'v3', credentials=creds)
            except Exception as e:
                print(f"⚠️ Calendar connection failed: {e}")
    
    def _get_all_calendar_ids(self):
        """Get all calendar IDs the user has access to."""
        try:
            calendar_list = self.service.calendarList().list().execute()
            return [cal['id'] for cal in calendar_list.get('items', [])]
        except HttpError:
            return ['primary']
    
    def get_today_events(self):
        """Get today's calendar events from ALL calendars."""
        return self.get_events_for_date(days_offset=0)
    
    def get_upcoming_events(self, days=7, max_results=10):
        """Get upcoming events for the next N days from ALL calendars."""
        if not self.service:
            return []
        
        try:
            now = datetime.datetime.utcnow()
            end_date = now + datetime.timedelta(days=days)
            
            all_events = []
            calendar_ids = self._get_all_calendar_ids()
            
            for cal_id in calendar_ids:
                try:
                    events_result = self.service.events().list(
                        calendarId=cal_id,
                        timeMin=now.isoformat() + 'Z',
                        timeMax=end_date.isoformat() + 'Z',
                        maxResults=max_results,
                        singleEvents=True,
                        orderBy='startTime'
                    ).execute()
                    all_events.extend(events_result.get('items', []))
                except HttpError:
                    continue
            
            # Sort by start time and limit results
            all_events.sort(key=lambda x: x.get('start', {}).get('dateTime', x.get('start', {}).get('date', '')))
            return all_events[:max_results]
        except HttpError as e:
            print(f"⚠️ Calendar error: {e}")
            return []
    
    def get_schedule_summary(self):
        """Get a natural language summary for Olivia to speak."""
        events = self.get_today_events()
        
        if not events:
            return "Your calendar is clear for today - no scheduled events!"
        
        if len(events) == 1:
            summary = "You have 1 event today"
        else:
            summary = f"You have {len(events)} events today"
        
        # Describe first few events
        for i, event in enumerate(events[:3]):
            start = event.get('start', '')
            if 'T' in start:
                # Parse time
                try:
                    time_str = datetime.datetime.fromisoformat(start.replace('Z', '+00:00'))
                    time_formatted = time_str.strftime('%I:%M %p').lstrip('0')
                except:
                    time_formatted = start
            else:
                time_formatted = "all day"
            
            if i == 0:
                summary += f": {event['summary']} at {time_formatted}"
            else:
                summary += f", then {event['summary']} at {time_formatted}"
        
        if len(events) > 3:
            summary += f", and {len(events) - 3} more"
        
        return summary + "."
    
    def get_events_for_date(self, days_offset=0):
        """Get events for a specific day (0=today, 1=tomorrow, etc.) from ALL calendars.
        Uses local date calculation to handle timezone differences."""
        if not self.service:
            return []
        
        try:
            # Use local time for "today/tomorrow" calculation, not UTC
            import time
            local_now = datetime.datetime.now()  # Local time
            target_date = local_now + datetime.timedelta(days=days_offset)
            
            # Create start/end in local time, then convert to RFC3339 format
            start_of_day = target_date.replace(hour=0, minute=0, second=0, microsecond=0)
            end_of_day = start_of_day + datetime.timedelta(days=1)
            
            # Format with timezone offset for Google API
            # Use ISO format with explicit timezone
            tz_offset = time.strftime('%z')
            tz_formatted = f"{tz_offset[:3]}:{tz_offset[3:]}" if tz_offset else 'Z'
            
            time_min = start_of_day.strftime('%Y-%m-%dT%H:%M:%S') + tz_formatted
            time_max = end_of_day.strftime('%Y-%m-%dT%H:%M:%S') + tz_formatted
            
            all_events = []
            calendar_ids = self._get_all_calendar_ids()
            
            for cal_id in calendar_ids:
                try:
                    events_result = self.service.events().list(
                        calendarId=cal_id,
                        timeMin=time_min,
                        timeMax=time_max,
                        singleEvents=True,
                        orderBy='startTime'
                    ).execute()
                    
                    for e in events_result.get('items', []):
                        all_events.append({
                            'summary': e.get('summary', 'Untitled'),
                            'start': e.get('start', {}).get('dateTime', e.get('start', {}).get('date', '')),
                            'end': e.get('end', {}).get('dateTime', e.get('end', {}).get('date', '')),
                            'location': e.get('location', ''),
                        })
                except HttpError:
                    continue
            
            all_events.sort(key=lambda x: x.get('start', ''))
            return all_events
        except HttpError as e:
            print(f"⚠️ Calendar error: {e}")
            return []
    
    def get_tomorrow_summary(self):
        """Get a natural language summary of tomorrow's events."""
        events = self.get_events_for_date(days_offset=1)
        
        if not events:
            return "Your calendar is clear for tomorrow - no scheduled events!"
        
        if len(events) == 1:
            summary = "You have 1 event tomorrow"
        else:
            summary = f"You have {len(events)} events tomorrow"
        
        for i, event in enumerate(events[:3]):
            start = event.get('start', '')
            if 'T' in start:
                try:
                    time_str = datetime.datetime.fromisoformat(start.replace('Z', '+00:00'))
                    time_formatted = time_str.strftime('%I:%M %p').lstrip('0')
                except:
                    time_formatted = start
            else:
                time_formatted = "all day"
            
            if i == 0:
                summary += f": {event['summary']} at {time_formatted}"
            else:
                summary += f", then {event['summary']} at {time_formatted}"
        
        if len(events) > 3:
            summary += f", and {len(events) - 3} more"
        
        return summary + "."
    
    def create_event(self, summary, start_time, end_time, description="", location=""):
        """Create a new calendar event.
        
        Args:
            summary: Event title
            start_time: datetime object for start
            end_time: datetime object for end
            description: Optional event description
            location: Optional location
        
        Returns:
            Created event dict or None if failed
        """
        if not self.service:
            return None
        
        try:
            import time
            tz_offset = time.strftime('%z')
            tz_formatted = f"{tz_offset[:3]}:{tz_offset[3:]}" if tz_offset else '-07:00'
            
            event = {
                'summary': summary,
                'location': location,
                'description': description,
                'start': {
                    'dateTime': start_time.strftime('%Y-%m-%dT%H:%M:%S') + tz_formatted,
                    'timeZone': 'America/Denver',
                },
                'end': {
                    'dateTime': end_time.strftime('%Y-%m-%dT%H:%M:%S') + tz_formatted,
                    'timeZone': 'America/Denver',
                },
            }
            
            created_event = self.service.events().insert(
                calendarId='primary',
                body=event
            ).execute()
            
            print(f"✅ Created event: {created_event.get('summary')}")
            return created_event
        except HttpError as e:
            print(f"⚠️ Failed to create event: {e}")
            return None
    
    def delete_event(self, event_id):
        """Delete a calendar event by ID."""
        if not self.service:
            return False
        
        try:
            self.service.events().delete(
                calendarId='primary',
                eventId=event_id
            ).execute()
            print(f"✅ Deleted event: {event_id}")
            return True
        except HttpError as e:
            print(f"⚠️ Failed to delete event: {e}")
            return False
    
    def create_all_day_event(self, summary, date, recurrence=None, description=""):
        """Create an all-day event (like birthdays, holidays).
        
        Args:
            summary: Event title
            date: datetime object for the date
            recurrence: Optional - 'yearly', 'monthly', 'weekly', or None
            description: Optional description
        
        Returns:
            Created event dict or None if failed
        """
        if not self.service:
            return None
        
        try:
            event = {
                'summary': summary,
                'description': description,
                'start': {
                    'date': date.strftime('%Y-%m-%d'),
                },
                'end': {
                    'date': date.strftime('%Y-%m-%d'),
                },
            }
            
            # Add recurrence rule if specified
            if recurrence:
                rrule_map = {
                    'yearly': 'RRULE:FREQ=YEARLY',
                    'annually': 'RRULE:FREQ=YEARLY',
                    'monthly': 'RRULE:FREQ=MONTHLY',
                    'weekly': 'RRULE:FREQ=WEEKLY',
                    'daily': 'RRULE:FREQ=DAILY',
                }
                if recurrence.lower() in rrule_map:
                    event['recurrence'] = [rrule_map[recurrence.lower()]]
            
            created_event = self.service.events().insert(
                calendarId='primary',
                body=event
            ).execute()
            
            print(f"✅ Created all-day event: {created_event.get('summary')}")
            return created_event
        except HttpError as e:
            print(f"⚠️ Failed to create all-day event: {e}")
            return None
    
    def find_events_by_name(self, search_term, days_ahead=30):
        """Find events by name/summary.
        
        Args:
            search_term: Text to search for in event titles
            days_ahead: How many days ahead to search (default 30)
        
        Returns:
            List of matching events with id, summary, start, end, location
        """
        if not self.service:
            return []
        
        try:
            import time
            local_now = datetime.datetime.now()
            time_min = local_now
            time_max = local_now + datetime.timedelta(days=days_ahead)
            
            tz_offset = time.strftime('%z')
            tz_formatted = f"{tz_offset[:3]}:{tz_offset[3:]}" if tz_offset else '-07:00'
            
            events_result = self.service.events().list(
                calendarId='primary',
                timeMin=time_min.strftime('%Y-%m-%dT%H:%M:%S') + tz_formatted,
                timeMax=time_max.strftime('%Y-%m-%dT%H:%M:%S') + tz_formatted,
                singleEvents=True,
                orderBy='startTime',
                q=search_term  # Google Calendar search
            ).execute()
            
            matches = []
            for e in events_result.get('items', []):
                matches.append({
                    'id': e.get('id'),
                    'summary': e.get('summary', 'Untitled'),
                    'start': e.get('start', {}).get('dateTime', e.get('start', {}).get('date', '')),
                    'end': e.get('end', {}).get('dateTime', e.get('end', {}).get('date', '')),
                    'location': e.get('location', ''),
                })
            
            return matches
        except HttpError as e:
            print(f"⚠️ Failed to search events: {e}")
            return []
    
    def update_event(self, event_id, summary=None, location=None, description=None, start_time=None, end_time=None):
        """Update an existing calendar event.
        
        Args:
            event_id: The event ID to update
            summary: New title (optional)
            location: New location (optional)
            description: New description (optional)
            start_time: New start datetime (optional)
            end_time: New end datetime (optional)
        
        Returns:
            Updated event dict or None if failed
        """
        if not self.service:
            return None
        
        try:
            # First, get the existing event
            event = self.service.events().get(
                calendarId='primary',
                eventId=event_id
            ).execute()
            
            # Update fields if provided
            if summary:
                event['summary'] = summary
            if location:
                event['location'] = location
            if description:
                event['description'] = description
            
            if start_time:
                import time
                tz_offset = time.strftime('%z')
                tz_formatted = f"{tz_offset[:3]}:{tz_offset[3:]}" if tz_offset else '-07:00'
                event['start'] = {
                    'dateTime': start_time.strftime('%Y-%m-%dT%H:%M:%S') + tz_formatted,
                    'timeZone': 'America/Denver',
                }
            
            if end_time:
                import time
                tz_offset = time.strftime('%z')
                tz_formatted = f"{tz_offset[:3]}:{tz_offset[3:]}" if tz_offset else '-07:00'
                event['end'] = {
                    'dateTime': end_time.strftime('%Y-%m-%dT%H:%M:%S') + tz_formatted,
                    'timeZone': 'America/Denver',
                }
            
            # Update the event
            updated_event = self.service.events().update(
                calendarId='primary',
                eventId=event_id,
                body=event
            ).execute()
            
            print(f"✅ Updated event: {updated_event.get('summary')}")
            return updated_event
        except HttpError as e:
            print(f"⚠️ Failed to update event: {e}")
            return None


# Global service instances (lazy loaded)
_gmail = None
_calendar = None

def get_gmail():
    """Get Gmail service (singleton)."""
    global _gmail
    if _gmail is None and GOOGLE_AVAILABLE:
        _gmail = GmailService()
    return _gmail

def get_calendar():
    """Get Calendar service (singleton)."""
    global _calendar
    if _calendar is None and GOOGLE_AVAILABLE:
        _calendar = CalendarService()
    return _calendar


# For Olivia's brain to use
def get_daily_briefing():
    """Get a complete daily briefing for Olivia."""
    parts = []
    
    calendar = get_calendar()
    if calendar and calendar.service:
        parts.append(calendar.get_schedule_summary())
    
    gmail = get_gmail()
    if gmail and gmail.service:
        parts.append(gmail.get_email_summary())
    
    if not parts:
        return "I don't have access to your calendar or email yet. Would you like help setting that up?"
    
    return " ".join(parts)


if __name__ == "__main__":
    """Run directly to set up authentication."""
    print("🔐 Haven Google Authentication Setup")
    print("=" * 50)
    
    if not GOOGLE_AVAILABLE:
        print("\n❌ Google API libraries not installed!")
        print("   Run: pip install google-api-python-client google-auth-httplib2 google-auth-oauthlib")
        exit(1)
    
    if not CREDENTIALS_FILE.exists():
        print(f"\n❌ Missing credentials file: {CREDENTIALS_FILE}")
        print("\nTo set up Google integration:")
        print("1. Go to https://console.cloud.google.com/")
        print("2. Create a project and enable Gmail & Calendar APIs")
        print("3. Create OAuth 2.0 credentials (Desktop app)")
        print("4. Download and save as: credentials.json")
        print(f"   Save it here: {SCRIPT_DIR}")
        exit(1)
    
    print("\n📱 Opening browser for Google authentication...")
    creds = get_google_credentials()
    
    if creds:
        print("\n✅ Authentication successful!")
        print("\nTesting services...")
        
        gmail = get_gmail()
        if gmail.service:
            print(f"📧 Gmail: {gmail.get_email_summary()}")
        
        calendar = get_calendar()
        if calendar.service:
            print(f"📅 Calendar: {calendar.get_schedule_summary()}")
        
        print("\n🎉 Olivia now has access to your Gmail and Calendar!")
    else:
        print("\n❌ Authentication failed")