"""
Resend webhook handler — receives delivery events and inbound emails.

NOT behind @role_required: Resend posts here unauthenticated.
Verification uses RESEND_WEBHOOK_SECRET via the Resend SDK.
"""

import resend
from quart import Blueprint, jsonify, request

from .core import config, execute, utcnow_iso

bp = Blueprint("webhooks", __name__, url_prefix="/webhooks")

# Maps Resend event types to (column_to_update, timestamp_column) pairs.
_EVENT_UPDATES: dict[str, tuple[str, str | None]] = {
    "email.delivered": ("delivered", "delivered_at"),
    "email.bounced": ("bounced", "bounced_at"),
    "email.opened": ("opened", "opened_at"),
    "email.clicked": ("clicked", "clicked_at"),
    "email.complained": ("complained", None),
}


@bp.route("/resend", methods=["POST"])
async def resend_webhook():
    """Handle Resend webhook events (delivery tracking + inbound email)."""
    body = await request.get_data()

    # Verify signature when secret is configured
    if config.RESEND_WEBHOOK_SECRET:
        svix_id = request.headers.get("svix-id", "")
        svix_timestamp = request.headers.get("svix-timestamp", "")
        svix_signature = request.headers.get("svix-signature", "")

        try:
            wh = resend.Webhooks(config.RESEND_WEBHOOK_SECRET)
            wh.verify(body, {
                "svix-id": svix_id,
                "svix-timestamp": svix_timestamp,
                "svix-signature": svix_signature,
            })
        except Exception:
            return jsonify({"error": "invalid signature"}), 401

    payload = await request.get_json()
    if not payload:
        return jsonify({"error": "empty payload"}), 400

    event_type = payload.get("type", "")
    data = payload.get("data", {})

    if event_type in _EVENT_UPDATES:
        _handle_delivery_event(event_type, data)
    elif event_type == "email.received":
        await _handle_inbound(data)

    return jsonify({"ok": True})


async def _handle_delivery_event(event_type: str, data: dict) -> None:
    """Update email_log with delivery event (idempotent)."""
    email_id = data.get("email_id", "")
    if not email_id:
        return

    last_event, ts_col = _EVENT_UPDATES[event_type]
    now = utcnow_iso()

    if ts_col:
        await execute(
            f"UPDATE email_log SET last_event = ?, {ts_col} = ? WHERE resend_id = ?",
            (last_event, now, email_id),
        )
    else:
        await execute(
            "UPDATE email_log SET last_event = ? WHERE resend_id = ?",
            (last_event, email_id),
        )


async def _handle_inbound(data: dict) -> None:
    """Store an inbound email (INSERT OR IGNORE on resend_id)."""
    resend_id = data.get("email_id", "")
    if not resend_id:
        return

    now = utcnow_iso()
    await execute(
        """INSERT OR IGNORE INTO inbound_emails
           (resend_id, message_id, in_reply_to, from_addr, to_addr,
            subject, text_body, html_body, received_at)
           VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?)""",
        (
            resend_id,
            data.get("message_id", ""),
            data.get("in_reply_to", ""),
            data.get("from", ""),
            data.get("to", [""])[0] if isinstance(data.get("to"), list) else data.get("to", ""),
            data.get("subject", ""),
            data.get("text", ""),
            data.get("html", ""),
            now,
        ),
    )