Gmail Skill

#!/usr/bin/env python3
"""
Gmail Skill - Read, search, send, and manage Gmail emails. Access Google contacts.

Supports multiple accounts with seamless OAuth browser flow.

Usage:
    python gmail_skill.py search "query" [--account EMAIL]
    python gmail_skill.py read EMAIL_ID [--account EMAIL]
    python gmail_skill.py list [--account EMAIL]
    python gmail_skill.py labels [--account EMAIL]
    python gmail_skill.py send --to EMAIL --subject "..." --body "..." [--account EMAIL]
    python gmail_skill.py mark-read EMAIL_ID [--account EMAIL]
    python gmail_skill.py mark-done EMAIL_ID [--account EMAIL]  # Archive (Gmail 'e')
    python gmail_skill.py contacts [--account EMAIL]
    python gmail_skill.py search-contacts "query" [--account EMAIL]
    python gmail_skill.py accounts                    # List authenticated accounts
    python gmail_skill.py logout [--account EMAIL]    # Remove account
"""

import argparse
import base64
import hashlib
import json
import os
import re
import sys
import textwrap
import webbrowser
from datetime import datetime
from email.mime.text import MIMEText
from email.mime.multipart import MIMEMultipart
from http.server import HTTPServer, BaseHTTPRequestHandler
from pathlib import Path
from typing import Optional
from urllib.parse import urlencode, parse_qs, urlparse
import threading
import secrets

# Email line width for readability (matches Superhuman style)
EMAIL_LINE_WIDTH = 72

# Check for required libraries
try:
    from google.auth.transport.requests import Request
    from google.oauth2.credentials import Credentials
    from googleapiclient.discovery import build
    from googleapiclient.errors import HttpError
    import requests
except ImportError:
    print("Error: Required libraries not installed.")
    print("Install with: pip install google-auth google-auth-oauthlib google-auth-httplib2 google-api-python-client requests")
    sys.exit(1)

# Paths
SKILL_DIR = Path(__file__).parent
TOKENS_DIR = SKILL_DIR / "tokens"
CREDENTIALS_FILE = SKILL_DIR / "credentials.json"
ACCOUNTS_META_FILE = SKILL_DIR / "accounts.json"

# Scopes - includes send and modify capabilities
SCOPES = [
    "https://www.googleapis.com/auth/gmail.readonly",
    "https://www.googleapis.com/auth/gmail.send",    # For sending (REQUIRES USER CONFIRMATION)
    "https://www.googleapis.com/auth/gmail.modify",  # For mark-read, archive, etc.
    "https://www.googleapis.com/auth/contacts.readonly",
    "https://www.googleapis.com/auth/contacts.other.readonly",
    "https://www.googleapis.com/auth/userinfo.email",  # To get email address
]

# Google OAuth endpoints
GOOGLE_AUTH_URL = "https://accounts.google.com/o/oauth2/v2/auth"
GOOGLE_TOKEN_URL = "https://oauth2.googleapis.com/token"
GOOGLE_USERINFO_URL = "https://www.googleapis.com/oauth2/v2/userinfo"

# Default OAuth client - user can override with their own credentials.json
# This is a "Desktop app" type client, where the secret is not truly secret
DEFAULT_CLIENT_CONFIG = {
    "installed": {
        "client_id": "YOUR_CLIENT_ID.apps.googleusercontent.com",
        "client_secret": "YOUR_CLIENT_SECRET",
        "auth_uri": "https://accounts.google.com/o/oauth2/auth",
        "token_uri": "https://oauth2.googleapis.com/token",
        "redirect_uris": ["http://localhost"]
    }
}


def get_client_config() -> dict:
    """Load OAuth client configuration."""
    if CREDENTIALS_FILE.exists():
        with open(CREDENTIALS_FILE) as f:
            return json.load(f)

    # Check if default config has been configured
    if DEFAULT_CLIENT_CONFIG["installed"]["client_id"].startswith("YOUR_"):
        print("\n" + "="*60)
        print("FIRST-TIME SETUP REQUIRED")
        print("="*60)
        print("\nTo use Gmail Reader, you need to create a Google Cloud OAuth client.")
        print("This is a one-time setup that takes ~2 minutes:\n")
        print("1. Go to: https://console.cloud.google.com/apis/credentials")
        print("2. Create a project (or select existing)")
        p