from __future__ import annotations
from quart import Blueprint, current_app, render_template, request
from sqlalchemy import func, select

from steward.alerts.service import active_alerts, alert_label
from steward.auth.middleware import require_role
from steward.core.status import collect_status, sparkline_svg
from steward.models.hosts import Host
from steward.models.users import UserRole

status_bp = Blueprint("status", __name__, url_prefix="/status")


def _summarize(entries) -> tuple[int, int, int]:
    up = sum(1 for e in entries if e.status == "up")
    down = sum(1 for e in entries if e.status == "down")
    pending = sum(1 for e in entries if e.status == "pending")
    return up, down, pending


@status_bp.get("/")
@require_role(UserRole.viewer)
async def index():
    poll_interval = current_app.config.get("MONITORS_POLL_INTERVAL", 60)
    return await render_template("status/index.html", poll_interval=poll_interval)


@status_bp.get("/rows")
@require_role(UserRole.viewer)
async def rows():
    """HTMX fragment — what is wrong (down monitors, active alerts), then the
    full status list, refreshed on poll."""
    async with current_app.db_sessionmaker() as db:
        entries = await collect_status(db)
        alerts = await active_alerts(db)
    for e in entries:
        if e.spark:
            e.spark_svg = sparkline_svg(e.spark)
    up, down, pending = _summarize(entries)
    return await render_template(
        "status/rows.html", entries=entries, up=up, down=down, pending=pending,
        alerts=alerts, problems=[e for e in entries if e.status == "down"],
    )


@status_bp.get("/widget")
@require_role(UserRole.viewer)
async def widget():
    """HTMX dashboard 'Overview' widget — the single at-a-glance summary that
    replaced the old fixed top strip: host count + monitor up/down/pending +
    problem list + an alerts link."""
    async with current_app.db_sessionmaker() as db:
        entries = await collect_status(db)
        total_hosts = (await db.execute(
            select(func.count()).select_from(Host))).scalar()
        alerts = await active_alerts(db)
    up, down, pending = _summarize(entries)
    return await render_template(
        "status/widget.html",
        entries=entries, up=up, down=down, pending=pending,
        total_hosts=total_hosts, alerts=overview_alerts(alerts),
        widget_id=request.args.get("wid", "0"),
    )


def overview_alerts(alerts) -> list[dict]:
    """The Overview's alert lines: breaching or silent first, then those
    someone has taken; each {rule, label, since}."""
    order = {"firing": 0, "no_data": 1, "pending": 2, "acknowledged": 3}
    rows = []
    for state, rule in alerts:
        label = alert_label(state)
        since = state.no_data_since if label == "no_data" else state.last_transition_at
        rows.append({"rule": rule, "label": label, "since": since})
    return sorted(rows, key=lambda r: order.get(r["label"], 9))