#  use command line with URL of school calendar then any guest emails -g email.com -g email.com 
#  python generate_links.py https://newsletters.naavi.com/i/JKdOO0M/issue-16/page/5 -g joanna.gilligan@gmail.com
import requests
from bs4 import BeautifulSoup
from datetime import datetime
import urllib.parse
from datetime import date
import sys
import argparse
import re

def create_google_calendar_url(title, start_time, end_time=None, description="", location="", guests=None):
    """
    Generates a Google Calendar "Add to Calendar" URL.

    Args:
        title (str): The title of the event.
        start_time (datetime): The start time of the event.
        end_time (datetime, optional): The end time of the event. Defaults to None.
        description (str, optional): The event description. Defaults to "".
        location (str, optional): The event location. Defaults to "".
        guests (list, optional): A list of guest email addresses. Defaults to None.

    Returns:
        str: The Google Calendar URL.
    """
    base_url = "https://www.google.com/calendar/render?action=TEMPLATE"

    # Format date and time for Google Calendar URL (YYYYMMDDTHHMMSS or YYYYMMDDTHHMMSSZ)
    start_time_str = start_time.strftime("%Y%m%dT%H%M%S")

    # For single time events, use the start time as both start and end
    if end_time:
        end_time_str = end_time.strftime("%Y%m%dT%H%M%S")
        dates_param = f"{start_time_str}/{end_time_str}"
    else:
        dates_param = f"{start_time_str}/{start_time_str}" # Use start/start for single time events


    params = {
        "text": title,
        "dates": dates_param,
        "details": description,
        "location": location
    }

    print(f"  In create_google_calendar_url - guests: {guests}")

    # --- THIS IS THE PART THAT ADDS THE GUESTS ---
    if guests:
        params["add"] = ",".join(guests)
    # -------------------------------------------

    # Encode parameters
    encoded_params = urllib.parse.urlencode(params)

    return f"{base_url}&{encoded_params}"

def generate_calendar_links_from_rows(url, guests=None): 
    """
    Fetches a webpage, looks for rows with a specific date format and title,
    and generates an HTML string with Google Calendar links.

    Args:
        url (str): The URL of the webpage.

    Returns:
        str: An HTML string with calendar links, or None if an error occurs.
    """
    try:
        response = requests.get(url)
        response.raise_for_status()  # Raise an exception for bad status codes
    except requests.exceptions.RequestException as e:
        print(f"Error fetching the URL: {e}")
        return None

    if not response.content:
        print("Error: Received empty content from the URL.")
        return None

    try:
        soup = BeautifulSoup(response.content, 'html.parser')
    except Exception as e:
        print(f"Error parsing HTML content: {e}")
        # print(f"Beginning of content: {response.content[:500].decode('utf-8', errors='ignore')}")
        return None

    html_output = "<h1>Calendar Links</h1><ul>"
    events = []
    current_year = date.today().year # Get the current year

    # Find all table rows (<tr>) on the page
    rows = soup.find_all('tr')

    if not rows:
        html_output += "<li>No table rows found on the page.</li>"
        html_output += "</ul>"
        return html_output

    for i, row in enumerate(rows):
        # Get the text content of the row, replacing &nbsp; with a space for easier splitting
        row_text = row.get_text(" ", strip=True).replace('\xa0', ' ')

        # Look for a pattern that matches "DayOfWeek DayOfMonth Month" at the beginning of the string
        # Example: "Sat 09 August"
        # We'll use regex for a more robust match
        import re
        date_match = re.match(r'^\w{3}\s+\d{1,2}\s+\w+', row_text)

        if date_match:
            date_str_raw = date_match.group(0)
            remaining_text = row_text[len(date_str_raw):].strip()

            print(f"Processing row {i+1}:")
            print(f"  Raw date string found: '{date_str_raw}'")
            # Attempt to parse the date string
            try:
                # Assuming the date format is "DayOfWeek DayOfMonth Month" (e.g., "Sat 09 August")
                # We'll add the current year and a default time (e.g., 00:00) for parsing
                # The actual time will be extracted separately if needed or assumed.
                date_for_parsing = f"{date_str_raw} {current_year} 07:00"
                print(f"  String for parsing: '{date_for_parsing}'")
                # Format string: "%a %d %B %Y %H:%M" for "Sat 09 August 2023 00:00"
                event_datetime = datetime.strptime(date_for_parsing, "%a %d %B %Y %H:%M")
                print(f"  Parsed datetime object: {event_datetime}")

                # Look for the last occurrence of a space (or series of spaces) after the date
                # and assume the title is after that. This might need refinement based on actual data.
                # Alternatively, look for the content after the date match.
                title_parts = remaining_text.split(' ')
                # Find the first non-empty part after the date
                title = "Event" # Default title
                for part in title_parts:
                    if part:
                        title = part
                        break

                # A more robust way might be to look for the content after the first few words of the date match
                title_start_index = len(date_str_raw) + 1
                if title_start_index < len(row_text):
                    title = row_text[title_start_index:].strip() or "Event"

                # If the event also has a time in the row, you might need to extract that
                # and update event_datetime. This requires more specific pattern matching
                # for time (e.g., "HH:MM"). For simplicity, we'll use the parsed date with
                # a default time from the date parsing.

                calendar_url = create_google_calendar_url(
                    title=title,
                    start_time=event_datetime,
                    guests=guests  # Pass the guest emails if provided
                    # Add description, end_time, location if available
                )
                print(f"  Generated Calendar URL (start_time part): {calendar_url.split('&dates=')[1].split('&')[0]}")
                print("-" * 20) # Separator for clarity
                print(f"  Full generated Calendar URL: {calendar_url}")

                events.append({"title": title, "url": calendar_url})
                
            except ValueError as e:
                print(f"Could not parse date string '{date_str_raw}' in row {i+1}: {e}")
                continue # Skip this row if date parsing fails


    if not events:
        html_output += "<li>No valid events with the specified date format found in the rows.</li>"
    else:
        for event in events:
            html_output += f'<li><a href="{event["url"]}" target="_blank">{event["title"]}</a></li>'


    html_output += "</ul>"

    return html_output

if __name__ == "__main__":
    parser = argparse.ArgumentParser(description="Generate Google Calendar links from a webpage table.")
    parser.add_argument("url", help="The URL of the webpage containing the event table.")
    parser.add_argument("-g", "--guest", action="append", help="Add a guest email address. Can be used multiple times.")

    args = parser.parse_args()

    print(f"Parsed arguments (args): {args}")
    print(f"Guest emails variable (guest_emails): {args.guest}")

    target_url = args.url
    guest_emails = args.guest # This will be a list of guest emails or None

    generated_html = generate_calendar_links_from_rows(target_url, guests=guest_emails) # Pass guests to the function

    if generated_html:
        # print(generated_html) # Print to console

        # To save to a file:
        with open("calendar_links.html", "w") as f:
             f.write(generated_html)
        print("\nHTML output saved to calendar_links.html")