app.py

# app.py

import os
import re
import json
import requests
import gradio as gr
from google.oauth2.credentials import Credentials
from googleapiclient.discovery import build
from agentpro import create_model, ReactAgent
from agentpro.tools import AresInternetTool

# ──────────────────────────────────────────────────────────────────────────────
# 1) READ ENVIRONMENT VARIABLES (set in HF Space Secrets)
# ──────────────────────────────────────────────────────────────────────────────
OPENAI_API_KEY      = os.getenv("OPENAI_API_KEY")
GOOGLE_CLIENT_ID    = os.getenv("GOOGLE_CLIENT_ID")
GOOGLE_CLIENT_SECRET= os.getenv("GOOGLE_CLIENT_SECRET")
ARES_API_KEY        = os.getenv("ARES_API_KEY")  # if you are using AresInternetTool

# Your HF Space URL (must match what you registered as redirect URI in Google Cloud Console)
HF_SPACE_URL = "https://huggingface.co/spaces/case-llm-traversaal/calendar-chatbot"

# ──────────────────────────────────────────────────────────────────────────────
# 2) GLOBAL IN-MEMORY STORAGE FOR TOKENS (basic demo)
# ──────────────────────────────────────────────────────────────────────────────
# In a production ­grade multiuser app, key by user ID or IP. Here, we keep one “default” slot.
user_tokens = {
    "default": None  # Will hold a dict { "access_token": ..., "refresh_token": ..., "expiry": ... }
}

# ──────────────────────────────────────────────────────────────────────────────
# 3) HELPERS: Build Google Auth URL / Extract & Exchange Code / Build Service
# ──────────────────────────────────────────────────────────────────────────────

def build_auth_url():
    """
    Construct the Google OAuth2 authorization URL. When the user clicks 'Connect', 
    we open this in a new tab. Google will redirect to HF_SPACE_URL?code=XXXX.
    """
    base = "https://accounts.google.com/o/oauth2/v2/auth"
    scope = "https://www.googleapis.com/auth/calendar.readonly https://www.googleapis.com/auth/calendar.events"
    params = {
        "client_id": GOOGLE_CLIENT_ID,
        "redirect_uri": HF_SPACE_URL,
        "response_type": "code",
        "scope": scope,
        "access_type": "offline",    # get a refresh token
        "prompt": "consent"          # always ask consent to receive a refresh token
    }
    # Build query string manually
    q = "&".join([f"{k}={requests.utils.quote(v)}" for k, v in params.items()])
    return f"{base}?{q}"

def extract_auth_code(full_redirect_url: str) -> str:
    """
    The user pastes the entire redirect URL (which contains '?code=XYZ&scope=...' etc.).
    We pull out the 'XYZ' (authorization code) to exchange for tokens.
    """
    match = re.search(r"[?&]code=([^&]+)", full_redirect_url)
    if match:
        return match.group(1)
    return None

def exchange_code_for_tokens(auth_code: str):
    """
    Given the single‐use auth_code from Google, exchange it at Google's token endpoint
    for access_token + refresh_token + expiry. Then store it in user_tokens["default"].
    """
    token_url = "https://oauth2.googleapis.com/token"
    data = {
        "code": auth_code,
        "client_id": GOOGLE_CLIENT_ID,
        "client_secret": GOOGLE_CLIENT_SECRET,
        "redirect_uri": HF_SPACE_URL,
        "grant_type": "authorization_code",
    }
    resp = requests.post(token_url, data=data)
    if resp.status_code != 200:
        return None, resp.text

    token_data = resp.json()
    # Example token_data: { "access_token": "...", "expires_in": 3599, "refresh_token": "...", "scope": "...", "token_type": "Bearer" }
    user_tokens["default"] = {
        "access_token":  token_data.get("access_token"),
        "refresh_token": token_data.get("refresh_token"),
        "token_uri":     token_url,
        "client_id":     GOOGLE_CLIENT_ID,
        "client_secret": GOOGLE_CLIENT_SECRET,
        "scopes": [
            "https://www.googleapis.com/auth/calendar.readonly",
            "https://www.googleapis.com/auth/calendar.events"
        ]
        # Note: You could also store expiry/time; google.oauth2.credentials will handle refreshing automatically.
    }
    return token_data, None

def get_calendar_service():
    """
    Build a googleapiclient ‘service’ object using the stored tokens. 
    If tokens exist, we can construct google.oauth2.credentials.Credentials, 
    which will auto-refresh if expired.
    """
    token_info = user_tokens.get("default")
    if not token_info:
        return None  # Not authenticated yet

    creds = Credentials(
        token=token_info["access_token"],
        refresh_token=token_info["refresh_token"],
        token_uri=token_info["token_uri"],
        client_id=token_info["client_id"],
        client_secret=token_info["client_secret"],
        scopes=token_info["scopes"],
    )
    try:
        service = build("calendar", "v3", credentials=creds)
    except Exception as e:
        return None
    return service

# ──────────────────────────────────────────────────────────────────────────────
# 4) IMPORT YOUR EXISTING TOOLS
#    (Assumes you placed them in a subfolder named ‘tools/’)
# ──────────────────────────────────────────────────────────────────────────────

from tools.current_datetime_tool import CurrentDateTimeTool
from tools.daily_event_summary_tool import DailyEventSummaryTool
from tools.weekly_event_summary_tool import WeeklyEventSummaryTool
from tools.modify_event_tool import ModifyEventTool

# ──────────────────────────────────────────────────────────────────────────────
# 5) FUNCTION TO BUILD A FRESH AGENT FOR EACH USER
#    (Because the ‘service’ object is user-specific once authenticated)
# ──────────────────────────────────────────────────────────────────────────────

def build_agent_for_user():
    """
    1. Build the OpenAI model via AgentPro.
    2. Build a user-specific Google Calendar ‘service’ via stored tokens.
    3. Instantiate each tool with that service (where required).
    4. Return a ReactAgent ready to run queries.
    """
    # 5.1) Create the LLM model
    model = create_model(
        provider    = "openai",
        model_name  = "gpt-3.5-turbo",
        api_key     = OPENAI_API_KEY,
        temperature = 0.3
    )

    # 5.2) Get the user’s Google Calendar service
    service = get_calendar_service()
    if service is None:
        return None  # Not authenticated yet

    # 5.3) Instantiate each tool, passing ‘service’ where needed
    daily_planner_tool   = DailyEventSummaryTool(service=service)
    weekly_planner_tool  = WeeklyEventSummaryTool(service=service)
    modify_event_tool    = ModifyEventTool(service=service)
    current_dt_tool      = CurrentDateTimeTool()
    ares_tool            = AresInternetTool(ARES_API_KEY)

    tools_list = [
        daily_planner_tool,
        weekly_planner_tool,
        current_dt_tool,
        modify_event_tool,
        ares_tool,
    ]

    # 5.4) Create and return the ReactAgent
    agent = ReactAgent(model=model, tools=tools_list)
    return agent

# ──────────────────────────────────────────────────────────────────────────────
# 6) GRADIO CALLBACKS FOR AUTHENTICATION & EXCHANGE
# ──────────────────────────────────────────────────────────────────────────────

def open_google_oauth():
    """
    Called when user clicks “Connect Google Calendar.” Returns a message telling 
    them to copy the URL that opens.
    """
    url = build_auth_url()
    # Attempt to open in a new tab. (Browsers may block this; user can copy manually.)
    try:
        import webbrowser
        webbrowser.open_new_tab(url)
    except:
        pass
    return (
        "★ A new tab (or popup) should have opened for you to log in.\n\n"
        "If it did not, click this link manually:\n\n"
        f"{url}\n\n"
        "After granting access, you’ll end up on an error page. Copy the \
entire URL from your browser’s address bar (it contains “?code=…”) \
and paste it below."
    )

def handle_auth_code(full_redirect_url: str):
    """
    Called when user pastes the entire redirect URL back into our textbox.
    We parse out ‘code=…’, exchange it, and report success or failure.
    """
    code = extract_auth_code(full_redirect_url)
    if code is None:
        return "❌ Could not find ‘code’ in the URL you pasted. Please paste the exact URL you were redirected to."

    token_data, error = exchange_code_for_tokens(code)
    if error:
        return f"❌ Token exchange failed: {error}"
    return "✅ Successfully connected your Google Calendar! You can now ask about your events."

# ──────────────────────────────────────────────────────────────────────────────
# 7) GRADIO CHAT FUNCTION (uses user-specific agent)
# ──────────────────────────────────────────────────────────────────────────────

def chat_with_agent(user_input):
    """
    This is called whenever the user sends a chat query. 
    If not authenticated, prompt them to connect first. Otherwise, 
    build a fresh agent for this user and get a response.
    """
    # 7.1) Do we have a Calendar ‘service’ for this user yet?
    service = get_calendar_service()
    if service is None:
        return "❌ Please connect your Google Calendar first (use the button above)."

    # 7.2) Build a new Agent with the user’s Calendar service
    agent = build_agent_for_user()
    if agent is None:
        return "❌ Something went wrong building the agent. Ensure you completed Calendar authentication."

    # 7.3) Run the agent on the user’s input
    try:
        response = agent.run(user_input)
        return response.final_answer
    except Exception as e:
        return "❌ Exception in agent.run():\n" + repr(e)

# ──────────────────────────────────────────────────────────────────────────────
# 8) ASSEMBLE GRADIO INTERFACE
# ──────────────────────────────────────────────────────────────────────────────

with gr.Blocks() as demo:
    gr.Markdown("## 🗓️ Calendar Chatbot (Gradio + HF Spaces)")

    # ————————————————
    # A) CONNECT GOOGLE CALENDAR SECTION
    # ————————————————
    with gr.Row():
        connect_btn   = gr.Button("🔗 Connect Google Calendar")
        auth_message  = gr.Textbox(label="Auth Instructions / Status", interactive=False)

    connect_btn.click(fn=open_google_oauth, outputs=auth_message)

    auth_code_input = gr.Textbox(
        lines=1, 
        placeholder="Paste full Google redirect URL here (contains ‘code=…’)",
        label="Step 2: Paste full redirect URL"
    )
    auth_status = gr.Textbox(label="Authentication Result", interactive=False)
    auth_code_input.submit(fn=handle_auth_code, inputs=auth_code_input, outputs=auth_status)

    gr.Markdown("---")

    # ————————————————
    # B) CHAT SECTION
    # ————————————————
    chat_input  = gr.Textbox(lines=2, placeholder="E.g., What’s on my calendar today?")
    chat_output = gr.Textbox(label="Response", interactive=False)

    chat_input.submit(fn=chat_with_agent, inputs=chat_input, outputs=chat_output)

    # You can also add a “Send” button if you like:
    # send_btn = gr.Button("✉️ Send")
    # send_btn.click(fn=chat_with_agent, inputs=chat_input, outputs=chat_output)

demo.launch()