app/admin/router.py

"""
app/admin/router.py
───────────────────
Secure FastAPI router for the Admin Panel.

Security design:
  • All /admin/* routes require HTTP Basic Auth.
  • Credentials are compared using secrets.compare_digest() to prevent
    timing-based attacks — NOT a simple == comparison.
  • Wrong credentials always return 401 with WWW-Authenticate header.
  • Admin routes are completely isolated from the main app and Gradio UI.

Endpoints:
  GET  /admin                → Serves the premium admin.html SPA
  GET  /api/admin/sessions   → Returns all session summaries (JSON)
  GET  /api/admin/sessions/{session_id}  → Returns full session transcript
  DELETE /api/admin/sessions/{session_id} → Deletes a session
"""

import secrets
import logging
import asyncio
import time
import random
import smtplib
import socket
import json as _json
import urllib.parse
from email.mime.text import MIMEText
from email.mime.multipart import MIMEMultipart
from pathlib import Path
from typing import Dict, Optional

import pandas as pd
import io
from fastapi import APIRouter, Depends, HTTPException, status
from fastapi.responses import HTMLResponse, JSONResponse, StreamingResponse
from fastapi.security import HTTPBasic, HTTPBasicCredentials
from pydantic import BaseModel

from app.services.session_store import get_all_sessions, get_session, delete_session, _list_json_files, _read_json
from app.core.config import get_settings

logger = logging.getLogger(__name__)
settings = get_settings()

# Credentials are now loaded from settings (environment variables)

# ── Security scheme ───────────────────────────────────────────────────────────
security = HTTPBasic()

# ── Router ────────────────────────────────────────────────────────────────────
admin_router = APIRouter(tags=["admin"])

# ── OTP Store (In-memory for simplicity) ──────────────────────────────────────
# Format: {username: {"code": "123456", "expires": timestamp}}
_otp_store: Dict[str, dict] = {}
OTP_EXPIRY_SECONDS = 300  # 5 minutes

# ── Path to the admin HTML template ──────────────────────────────────────────
_ADMIN_HTML_PATH = Path(__file__).parent / "templates" / "admin.html"


# ── Auth dependency ───────────────────────────────────────────────────────────
def verify_admin(credentials: HTTPBasicCredentials = Depends(security)) -> str:
    """
    Verifies HTTP Basic credentials using constant-time comparison.
    Raises 401 for any mismatch. Returns the username on success.
    """
    correct_username = secrets.compare_digest(
        credentials.username.encode("utf-8"),
        settings.admin_user.encode("utf-8"),
    )
    correct_password = secrets.compare_digest(
        credentials.password.encode("utf-8"),
        settings.admin_pass.encode("utf-8"),
    )
    if not (correct_username and correct_password):
        logger.warning(
            "Admin auth failed for user: '%s'", credentials.username
        )
        raise HTTPException(
            status_code=status.HTTP_401_UNAUTHORIZED,
            detail="Invalid admin credentials.",
        )
    return credentials.username


# ── OTP Endpoints ─────────────────────────────────────────────────────────────


class LoginRequest(BaseModel):
    username: str
    password: str

class OTPVerifyRequest(BaseModel):
    username: str
    password: str
    code: str

@admin_router.post("/api/admin/request-otp", include_in_schema=False)
async def request_otp(req: LoginRequest):
    """
    Verifies password and generates a 6-digit OTP.
    Sends the OTP to the configured admin email.
    """
    if not (secrets.compare_digest(req.username, settings.admin_user) and 
            secrets.compare_digest(req.password, settings.admin_pass)):
        raise HTTPException(status_code=401, detail="Invalid credentials.")
    
    # Generate 6-digit code
    code = "".join([str(random.randint(0, 9)) for _ in range(6)])
    _otp_store[req.username] = {
        "code": code,
        "expires": time.time() + OTP_EXPIRY_SECONDS
    }
    
    # Attempt to send email
    email_sent = False
    if settings.smtp_user and settings.smtp_pass:
        try:
            # Use to_thread to avoid blocking the event loop during SMTP network I/O
            await asyncio.to_thread(send_otp_email, settings.admin_email, code)
            email_sent = True
            logger.info("OTP email sent to %s", settings.admin_email)
        except Exception as e:
            logger.error("Failed to send OTP email: %s", e)
    else:
        logger.warning("SMTP credentials not configured. OTP will only be in logs.")

    # FALLBACK/LOG: Always log to console so the user is never locked out
    print("\n" + "="*50)
    print(f"  ADMIN OTP FOR {req.username.upper()}: {code}")
    print(f"  SENDING TO: {settings.admin_email} ({'SUCCESS' if email_sent else 'FAILED/SKIPPED'})")
    print("  EXPIRES IN 5 MINUTES")
    print("="*50 + "\n")
    
    return {
        "message": "OTP sent successfully.",
        "email_status": "sent" if email_sent else "logged_to_console_only"
    }


def send_otp_email(to_email: str, otp_code: str):
    """Sends a professional OTP email via SMTP. Run in thread."""
    msg = MIMEMultipart()
    msg['From'] = settings.smtp_user
    msg['To'] = to_email
    msg['Subject'] = f"Your Admin Access Code: {otp_code}"

    body = f"""
    <html>
    <body style="font-family: sans-serif; padding: 20px; color: #333;">
        <h2 style="color: #3b82f6;">Martechsol Admin Panel</h2>
        <p>Your one-time security code is:</p>
        <div style="font-size: 32px; font-weight: bold; letter-spacing: 5px; padding: 15px; background: #f3f4f6; border-radius: 8px; display: inline-block; margin: 10px 0;">
            {otp_code}
        </div>
        <p style="color: #666; font-size: 14px;">This code will expire in 5 minutes.</p>
        <hr style="border: 0; border-top: 1px solid #eee; margin-top: 20px;">
        <p style="font-size: 12px; color: #999;">If you did not request this code, please secure your account.</p>
    </body>
    </html>
    """
    msg.attach(MIMEText(body, 'html'))

    # Force IPv4 resolution to avoid "Network unreachable" IPv6 issues
    try:
        ais = socket.getaddrinfo(settings.smtp_server, settings.smtp_port, socket.AF_INET)
        target_ip = ais[0][4][0]
        logger.info("Resolved %s to IPv4: %s", settings.smtp_server, target_ip)
    except Exception as e:
        logger.error("DNS Resolution failed: %s", e)
        target_ip = settings.smtp_server

    logger.info("Attempting SMTP_SSL connection to %s:%d (via %s)", 
                settings.smtp_server, settings.smtp_port, target_ip)
    
    # Using the IP directly can sometimes bypass DNS/routing quirks
    with smtplib.SMTP_SSL(target_ip, settings.smtp_port, timeout=15) as server:
        server.login(settings.smtp_user, settings.smtp_pass)
        server.send_message(msg)


@admin_router.post("/api/admin/verify-otp", include_in_schema=False)
async def verify_otp(req: OTPVerifyRequest):
    """Verifies both the password and the OTP code."""
    # 1. Verify password first
    if not (secrets.compare_digest(req.username, settings.admin_user) and 
            secrets.compare_digest(req.password, settings.admin_pass)):
        raise HTTPException(status_code=401, detail="Invalid credentials.")
    
    # 2. Verify OTP
    stored = _otp_store.get(req.username)
    if not stored:
        raise HTTPException(status_code=400, detail="No OTP requested for this user.")
    
    if time.time() > stored["expires"]:
        del _otp_store[req.username]
        raise HTTPException(status_code=400, detail="OTP has expired. Please request a new one.")
    
    if not secrets.compare_digest(req.code, stored["code"]):
        raise HTTPException(status_code=401, detail="Invalid OTP code.")
    
    # Success — clear OTP and return
    del _otp_store[req.username]
    return {"message": "OTP verified."}


# ── Routes ────────────────────────────────────────────────────────────────────

@admin_router.get("/admin", response_class=HTMLResponse, include_in_schema=False)
async def admin_panel():
    """Serves the admin panel SPA."""
    try:
        html_content = _ADMIN_HTML_PATH.read_text(encoding="utf-8")
        return HTMLResponse(content=html_content, status_code=200)
    except FileNotFoundError:
        logger.error("admin.html template not found at %s", _ADMIN_HTML_PATH)
        raise HTTPException(
            status_code=500,
            detail="Admin panel template is missing. Please redeploy.",
        )


@admin_router.get("/api/admin/sessions", include_in_schema=False)
async def list_sessions(
    search: str = "",
    filter: str = "",
    skip: int = 0,
    limit: int = 50,
    username: str = Depends(verify_admin)
):
    """Returns paginated session summaries sorted by most recent activity."""
    sessions = await get_all_sessions(search=search, filter_type=filter, skip=skip, limit=limit)
    return JSONResponse(content={"sessions": sessions, "total": len(sessions)})

@admin_router.get("/api/admin/metrics", include_in_schema=False)
async def admin_metrics_endpoint(username: str = Depends(verify_admin)):
    from app.services.session_store import get_metrics
    metrics = await get_metrics()
    return JSONResponse(content=metrics)


@admin_router.get("/api/admin/sla-metrics", include_in_schema=False)
async def admin_sla_metrics_endpoint(username: str = Depends(verify_admin)):
    from app.services.session_store import get_sla_metrics
    metrics = await get_sla_metrics()
    return JSONResponse(content=metrics)


@admin_router.get("/api/admin/analytics", include_in_schema=False)
async def admin_analytics(username: str = Depends(verify_admin)):
    """Returns aggregated analytics for the dashboard."""
    from datetime import datetime, timedelta, timezone
    
    files = await asyncio.to_thread(_list_json_files)
    total_sessions = len(files)
    total_messages = 0
    
    now_utc = datetime.now(timezone.utc)
    today_start = now_utc.replace(hour=0, minute=0, second=0, microsecond=0)
    today_sessions = 0
    
    days_data = {}
    for i in range(6, -1, -1):
        d = (today_start - timedelta(days=i)).strftime("%Y-%m-%d")
        days_data[d] = {"sessions": 0, "messages": 0}

    for fpath in files:
        try:
            data = await asyncio.to_thread(_read_json, fpath)
            msg_count = data.get("message_count", 0)
            total_messages += msg_count
            
            created_str = data.get("created_at", "")
            if created_str:
                try:
                    created_dt = datetime.fromisoformat(created_str.replace('Z', '+00:00'))
                    if created_dt >= today_start:
                        today_sessions += 1
                        
                    date_str = created_dt.strftime("%Y-%m-%d")
                    if date_str in days_data:
                        days_data[date_str]["sessions"] += 1
                        days_data[date_str]["messages"] += msg_count
                except ValueError:
                    pass
        except Exception as e:
            logger.warning("Analytics: Failed to read %s: %s", fpath, e)

    trends = [{"date": k, "sessions": v["sessions"], "messages": v["messages"]} for k, v in days_data.items()]

    return JSONResponse(content={
        "total_sessions": total_sessions,
        "total_messages": total_messages,
        "today_sessions": today_sessions,
        "trends": trends
    })


@admin_router.get("/api/admin/sessions/{session_id}", include_in_schema=False)
async def get_session_detail(
    session_id: str, username: str = Depends(verify_admin)
):
    """Returns the full Q&A transcript for a specific session."""
    session_id = urllib.parse.unquote(session_id)
    if ".." in session_id or "/" in session_id or "\\" in session_id:
        raise HTTPException(status_code=400, detail="Invalid session ID format.")

    data = await get_session(session_id)
    if not data:
        raise HTTPException(
            status_code=404,
            detail=f"Session '{session_id}' not found.",
        )
    return JSONResponse(content=data)


@admin_router.delete("/api/admin/sessions/{session_id}", include_in_schema=False)
async def remove_session(
    session_id: str, username: str = Depends(verify_admin)
):
    """Deletes a session file permanently."""
    session_id = urllib.parse.unquote(session_id)
    if ".." in session_id or "/" in session_id or "\\" in session_id:
        raise HTTPException(status_code=400, detail="Invalid session ID format.")

    success = await delete_session(session_id)
    if not success:
        raise HTTPException(status_code=500, detail="Failed to delete session.")
    return JSONResponse(content={"deleted": session_id})


@admin_router.delete("/api/admin/sessions/{session_id}/chats/{chat_id}", include_in_schema=False)
async def delete_chat_thread(
    session_id: str, chat_id: int, username: str = Depends(verify_admin)
):
    """Deletes a specific chat thread from a session."""
    from app.services.session_store import _get_lock, _get_session_path, _write_json
    
    session_id = urllib.parse.unquote(session_id)
    if ".." in session_id or "/" in session_id or "\\" in session_id:
        raise HTTPException(status_code=400, detail="Invalid session ID format.")

    lock = await _get_lock(session_id)
    path = _get_session_path(session_id)
    async with lock:
        if path.exists():
            data = await asyncio.to_thread(_read_json, path)
            data["messages"] = [m for m in data.get("messages", []) if m.get("chat_id", 1) != chat_id]
            data["message_count"] = len(data["messages"])
            await asyncio.to_thread(_write_json, path, data)
    return {"status": "ok"}


class ReplyRequest(BaseModel):
    message: str
    chat_id: Optional[int] = None

@admin_router.post("/api/admin/sessions/{session_id}/block", include_in_schema=False)
async def block_session(session_id: str, username: str = Depends(verify_admin)):
    from app.services.session_store import update_session_field
    await update_session_field(session_id, "blocked", True)
    return {"status": "blocked"}

@admin_router.post("/api/admin/sessions/{session_id}/unblock", include_in_schema=False)
async def unblock_session(session_id: str, username: str = Depends(verify_admin)):
    from app.services.session_store import update_session_field
    await update_session_field(session_id, "blocked", False)
    return {"status": "unblocked"}

@admin_router.post("/api/admin/sessions/{session_id}/takeover", include_in_schema=False)
async def takeover_session(
    session_id: str, username: str = Depends(verify_admin)
):
    """Admin takes over the chat."""
    from app.services.session_store import update_session_field
    session_id = urllib.parse.unquote(session_id)
    success = await update_session_field(session_id, "status", "HUMAN_TAKEOVER")
    if not success:
        raise HTTPException(status_code=404, detail="Session not found")
    return {"status": "success"}

@admin_router.post("/api/admin/sessions/{session_id}/end_takeover", include_in_schema=False)
async def end_takeover_session(
    session_id: str, username: str = Depends(verify_admin)
):
    """Admin returns control to AI."""
    from app.services.session_store import update_session_field
    session_id = urllib.parse.unquote(session_id)
    success = await update_session_field(session_id, "status", "AI")
    if not success:
        raise HTTPException(status_code=404, detail="Session not found")
    return {"status": "success"}

@admin_router.post("/api/admin/sessions/{session_id}/archive", include_in_schema=False)
async def archive_session_endpoint(session_id: str, username: str = Depends(verify_admin)):
    from app.services.session_store import update_session_field
    session_id = urllib.parse.unquote(session_id)
    success = await update_session_field(session_id, "archived", True)
    if not success:
        raise HTTPException(status_code=404, detail="Session not found")
    return {"status": "archived"}

@admin_router.post("/api/admin/sessions/{session_id}/unarchive", include_in_schema=False)
async def unarchive_session_endpoint(session_id: str, username: str = Depends(verify_admin)):
    from app.services.session_store import update_session_field
    session_id = urllib.parse.unquote(session_id)
    success = await update_session_field(session_id, "archived", False)
    if not success:
        raise HTTPException(status_code=404, detail="Session not found")
    return {"status": "unarchived"}

@admin_router.post("/api/admin/sessions/{session_id}/chats/{chat_id}/archive", include_in_schema=False)
async def archive_chat_thread_endpoint(session_id: str, chat_id: int, username: str = Depends(verify_admin)):
    from app.services.session_store import archive_chat_thread, get_session
    session_id = urllib.parse.unquote(session_id)
    
    # Rule: Only allow archiving if chat is ended.
    # A chat is ended if it's an old thread (chat_id < current_chat_id) OR if the whole session is ENDED.
    data = await get_session(session_id)
    if not data:
        raise HTTPException(status_code=404, detail="Session not found")
        
    current_chat_id = data.get("current_chat_id", 1)
    session_status = data.get("status", "AI")
    
    is_ended = (chat_id < current_chat_id) or (session_status == "ENDED")
    if not is_ended:
        raise HTTPException(status_code=400, detail="Cannot archive an active chat. End the chat first.")
        
    success = await archive_chat_thread(session_id, chat_id, True)
    if not success:
        raise HTTPException(status_code=500, detail="Failed to archive chat thread.")
    return {"status": "archived"}

@admin_router.post("/api/admin/sessions/{session_id}/chats/{chat_id}/unarchive", include_in_schema=False)
async def unarchive_chat_thread_endpoint(session_id: str, chat_id: int, username: str = Depends(verify_admin)):
    from app.services.session_store import archive_chat_thread
    session_id = urllib.parse.unquote(session_id)
    success = await archive_chat_thread(session_id, chat_id, False)
    if not success:
        raise HTTPException(status_code=500, detail="Failed to unarchive chat thread.")
    return {"status": "unarchived"}

@admin_router.post("/api/admin/sessions/{session_id}/end_chat", include_in_schema=False)
async def end_chat_completely(
    session_id: str, username: str = Depends(verify_admin)
):
    """Admin completely ends the chat session."""
    from app.services.session_store import update_session_field
    session_id = urllib.parse.unquote(session_id)
    success = await update_session_field(session_id, "status", "ENDED")
    if not success:
        raise HTTPException(status_code=404, detail="Session not found")
    return {"status": "success"}

@admin_router.post("/api/admin/sessions/{session_id}/reply", include_in_schema=False)
async def reply_session(session_id: str, req: ReplyRequest, username: str = Depends(verify_admin)):
    from app.services.session_store import save_message
    # Save with empty question so admin reply renders as 'Human Agent' message (no question field)
    # Pass chat_id so admin reply goes to the specific chat thread being viewed
    await save_message(session_id, "", req.message, chat_id=req.chat_id)
    return {"status": "sent"}

# ── Export Endpoints ─────────────────────────────────────────────────────────

@admin_router.get("/api/admin/export/session/{session_id}", include_in_schema=False)
async def export_session(
    session_id: str, format: str = "excel", username: str = Depends(verify_admin)
):
    """Exports a single session's transcript in Excel or JSON format."""
    data = await get_session(session_id)
    if not data:
        raise HTTPException(status_code=404, detail="Session not found.")

    messages = data.get("messages", [])
    export_data = []
    for msg in messages:
        export_data.append({
            "Timestamp": msg.get("timestamp", ""),
            "Question": msg.get("question", ""),
            "Answer": msg.get("answer", "")
        })

    if format.lower() == "json":
        return JSONResponse(
            content=export_data,
            headers={"Content-Disposition": f"attachment; filename=session_{session_id}.json"}
        )
    
    # Excel Export
    df = pd.DataFrame(export_data)
    output = io.BytesIO()
    with pd.ExcelWriter(output, engine='openpyxl') as writer:
        df.to_excel(writer, index=False, sheet_name='Transcript')
    
    output.seek(0)
    return StreamingResponse(
        output,
        media_type="application/vnd.openxmlformats-officedocument.spreadsheetml.sheet",
        headers={"Content-Disposition": f"attachment; filename=session_{session_id}.xlsx"}
    )


@admin_router.get("/api/admin/export/all", include_in_schema=False)
async def export_all_sessions(
    format: str = "excel", username: str = Depends(verify_admin)
):
    """Exports all sessions' transcripts in a single Excel or JSON file."""
    files = await asyncio.to_thread(_list_json_files)
    all_messages = []
    
    for fpath in files:
        try:
            data = await asyncio.to_thread(_read_json, fpath)
            session_id = data.get("session_id", fpath.stem)
            for msg in data.get("messages", []):
                all_messages.append({
                    "Session ID": session_id,
                    "Timestamp": msg.get("timestamp", ""),
                    "Question": msg.get("question", ""),
                    "Answer": msg.get("answer", ""),
                    "current_chat_id": data.get("current_chat_id", 1)
                })
        except Exception as e:
            logger.warning("Failed to read %s for export: %s", fpath, e)

    if format.lower() == "json":
        return JSONResponse(
            content=all_messages,
            headers={"Content-Disposition": "attachment; filename=all_chats_export.json"}
        )

    # Excel Export
    df = pd.DataFrame(all_messages)
    output = io.BytesIO()
    with pd.ExcelWriter(output, engine='openpyxl') as writer:
        df.to_excel(writer, index=False, sheet_name='All Chats')
    
    output.seek(0)
    return StreamingResponse(
        output,
        media_type="application/vnd.openxmlformats-officedocument.spreadsheetml.sheet",
        headers={"Content-Disposition": "attachment; filename=all_chats_export.xlsx"}
    )


# ── WhatsApp Settings Endpoints ──────────────────────────────────────────────

def _get_whatsapp_settings_path() -> Path:
    """Returns the path to the WhatsApp settings JSON file."""
    settings = get_settings()
    base = Path("/data") if Path("/data").exists() else Path("data")
    base.mkdir(parents=True, exist_ok=True)
    return base / "whatsapp_settings.json"

def get_whatsapp_settings() -> dict:
    """Reads WhatsApp settings from persistent JSON file, falling back to env vars."""
    path = _get_whatsapp_settings_path()
    settings = get_settings()
    defaults = {
        "admin_number": settings.meta_whatsapp_admin_number,
        "phone_id": settings.meta_whatsapp_phone_id,
        "token": settings.meta_whatsapp_token,
    }
    if path.exists():
        try:
            with open(path, "r", encoding="utf-8") as f:
                saved = _json.load(f)
            # Merge: saved values override defaults if present
            for k in defaults:
                if saved.get(k):
                    defaults[k] = saved[k]
        except Exception:
            pass
    return defaults

def _save_whatsapp_settings(data: dict) -> None:
    path = _get_whatsapp_settings_path()
    with open(path, "w", encoding="utf-8") as f:
        _json.dump(data, f, indent=2)


class WhatsAppSettingsRequest(BaseModel):
    admin_number: str = ""
    phone_id: str = ""
    token: str = ""


@admin_router.get("/api/admin/settings/whatsapp", include_in_schema=False)
async def get_whatsapp_config(username: str = Depends(verify_admin)):
    ws = get_whatsapp_settings()
    return {
        "admin_number": ws["admin_number"],
        "phone_id": ws["phone_id"],
        "token": bool(ws["token"]),  # Don't expose token, just indicate if set
    }


@admin_router.post("/api/admin/settings/whatsapp", include_in_schema=False)
async def save_whatsapp_config(req: WhatsAppSettingsRequest, username: str = Depends(verify_admin)):
    current = get_whatsapp_settings()
    updated = {
        "admin_number": req.admin_number.strip() if req.admin_number else current["admin_number"],
        "phone_id": req.phone_id.strip() if req.phone_id else current["phone_id"],
        "token": req.token.strip() if req.token else current["token"],
    }
    _save_whatsapp_settings(updated)
    return {"status": "saved"}


@admin_router.post("/api/admin/settings/whatsapp/test", include_in_schema=False)
async def test_whatsapp(username: str = Depends(verify_admin)):
    import httpx
    ws = get_whatsapp_settings()
    if not ws["phone_id"] or not ws["token"] or not ws["admin_number"]:
        raise HTTPException(status_code=400, detail="WhatsApp settings incomplete. Please save all 3 fields first.")

    admin_numbers = [n.strip() for n in ws["admin_number"].split(",") if n.strip()]
    if not admin_numbers:
        raise HTTPException(status_code=400, detail="No valid WhatsApp numbers configured.")

    url = f"https://graph.facebook.com/v17.0/{ws['phone_id']}/messages"
    headers = {
        "Authorization": f"Bearer {ws['token']}",
        "Content-Type": "application/json"
    }
    
    def _send_sync():
        import urllib.request
        import urllib.error
        import json
        import ssl
        
        errors = []
        ctx = ssl.create_default_context()
        ctx.check_hostname = False
        ctx.verify_mode = ssl.CERT_NONE
        
        for number in admin_numbers:
            payload = {
                "messaging_product": "whatsapp",
                "to": number,
                "type": "text",
                "text": {"body": "✅ Test notification from Martechsol Admin Panel.\nWhatsApp integration is working correctly!"}
            }
            data = json.dumps(payload).encode('utf-8')
            req = urllib.request.Request(url, data=data, headers=headers, method='POST')
            try:
                with urllib.request.urlopen(req, timeout=15.0, context=ctx) as response:
                    pass # success
            except urllib.error.HTTPError as e:
                err_msg = e.read().decode('utf-8')
                detail = err_msg
                try:
                    detail = json.loads(err_msg).get("error", {}).get("message", err_msg)
                except Exception:
                    pass
                errors.append(f"Error for {number}: {detail}")
            except Exception as e:
                errors.append(f"Network error for {number}: {type(e).__name__} - {str(e)}")
        return errors

    try:
        import asyncio
        errors = await asyncio.to_thread(_send_sync)
        if errors:
            raise HTTPException(status_code=400, detail=" | ".join(errors))
        return {"status": "sent"}
    except HTTPException:
        raise
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Unexpected error: {type(e).__name__} - {str(e)}")