// The rebuild queue tab of the dashboard (R3BU1LD QU3U3): pending and running
// rebuilds as a `JobqGraph`. Not an entry point: tabs.js imports it, owns the
// tab strip and the dashboard event stream, and calls the exports below. The
// builds' output and history are not here: they are the `builds` Grafana board,
// from the lines hive-c0re logs for each build.

import { $ } from "./common.js";
import { themedConfirm } from "@hive/shared/modal.js";
import { h, render } from "preact";
import { JobqGraph } from "@hive/shared/jobq-graph.js";

// Kept in sync from JobqGraph's `onUpdate` callback (see renderRebuildQueue
// below) — the component owns fetching GET /api/jobq/graph and renders the tree
// itself; this flat array is only for `onCancel`, which names the node it
// cancels in its confirm.
let jobqNodes = [];
let jobqGraphToken = 0;

// ─── rebuild queue ────────────────────────────────────────────────────────────
// R3BU1LD QU3U3 is `JobqGraph` (Preact, rendered via plain `render(h(...))`
// — no JSX pragma needed for either call, no mount wrapper: `render` is
// already the re-render/diff entry point, per mara on review) directly —
// no hand-rolled tree/roll-up rendering here anymore. The component owns
// fetching GET /api/jobq/graph and its own refetch (bump `jobqGraphToken`
// and render again); this page just reads its `onUpdate` callback to keep
// `jobqNodes` (the flat array) in sync for `onCancel` below.
//
// Cancel is the one action this page *does* wire up: the `cancellable`
// prop turns on the component's own per-node cancel button, which calls
// `onCancel(id)` rather than posting anything — the endpoint
// (`/api/rebuild-queue/{id}/cancel`) is this page's domain concept, not
// the generic component's.
// Split from `renderRebuildQueue` below: `replaceChildren()` only
// belongs on the *first* render, to clear the static "loading…"
// placeholder `#rebuild-queue-section` starts with in `index.html` —
// Preact doesn't know that placeholder is there, so a later render
// call must NOT repeat `replaceChildren()` (it would wipe Preact's own
// tracked children out from under its diffing rather than let it
// update them minimally).
function mountRebuildQueue() {
  const root = $("rebuild-queue-section");
  if (!root) return;
  root.replaceChildren();
  renderRebuildQueue();
}
function renderRebuildQueue() {
  const root = $("rebuild-queue-section");
  if (!root) return;
  render(
    h(JobqGraph, {
      endpoint: "/api/jobq/graph",
      cancellable: true,
      refreshToken: jobqGraphToken,
      onUpdate: (nodes) => {
        jobqNodes = nodes || [];
      },
      onCancel: async (id) => {
        const node = jobqNodes.find((n) => n.id === id);
        const label = node ? node.payload.label : "node " + id;
        if (
          !(await themedConfirm({
            message: `cancel ${label}? a group root cancels the whole subtree; a mid-tree node cancels just that branch.`,
            danger: true,
            confirmLabel: "✕ cancel",
          }))
        )
          return;
        try {
          const r = await fetch("/api/rebuild-queue/" + id + "/cancel", {
            method: "POST",
          });
          if (!r.ok) throw new Error("http " + r.status);
          // No manual refresh: cancel flips node state, which fires
          // rebuild_queue_changed over SSE — the existing handler below
          // already bumps jobqGraphToken and re-renders on that tick.
        } catch (err) {
          console.error("cancel failed", err);
        }
      },
    }),
    root,
  );
}

// ─── entry points for tabs.js ─────────────────────────────────────────────────
// Everything below is called by tabs.js, which owns the tab strip, the
// `/api/state` snapshot and the dashboard event stream.

/** Mount the rebuild queue. Called once, after the tab strip exists. The queue
 *  self-fetches on mount (JobqGraph's own effect). */
export function initBuilds() {
  mountRebuildQueue();
}

/** `rebuild_queue_changed`: a payload-less refetch trigger — `JobqGraph`
 *  owns the actual fetch. */
export function onRebuildQueueChanged() {
  jobqGraphToken += 1;
  renderRebuildQueue();
}