// app/api/tasks/[id]/fail/route.ts
// POST /api/tasks/[id]/fail
// Atomic state transition: in_progress → failed. Body: { error, log, retry }.

import { NextRequest, NextResponse } from "next/server";
import { BASE_URL, fetchRecord, updateRecord, PBRecord } from "@/lib/pb";

export const dynamic = "force-dynamic";

const COLLECTION = "tasks";
const MAX_RETRY = 3;

export async function POST(req: NextRequest, { params }: { params: { id: string } }) {
  let body: any = {};
  try {
    body = await req.json();
  } catch {
    return NextResponse.json({ error: "invalid JSON body" }, { status: 400 });
  }

  const errorMsg = (body?.error ?? "unknown error").toString().slice(0, 5000);
  const log = body?.log ?? null;

  // Atomic transition: in_progress → failed.
  const url = `${BASE_URL}/api/collections/${COLLECTION}/records/${encodeURIComponent(params.id)}?filter=status="in_progress"`;
  const res = await fetch(url, {
    method: "PATCH",
    headers: {
      Authorization: process.env.PB_TOKEN as string,
      "Content-Type": "application/json",
    },
    body: JSON.stringify({
      status: "failed",
      error: errorMsg,
      log,
      completed_at: new Date().toISOString().replace("T", " ").replace("Z", ""),
    }),
    cache: "no-store",
  });

  if (res.status === 404) {
    return NextResponse.json(
      { ok: false, error: "task not found or not in progress" },
      { status: 409 },
    );
  }
  if (!res.ok) {
    const text = await res.text();
    return NextResponse.json({ ok: false, error: `PB ${res.status}: ${text.slice(0, 200)}` }, { status: 500 });
  }
  const failed: PBRecord = await res.json();

  // Auto-retry if under the cap and the caller asked for it.
  let requeued = false;
  if (body?.retry !== false) {
    const current = await fetchRecord<PBRecord>(COLLECTION, params.id);
    const retryCount = (current.retry_count as number) ?? 0;
    if (retryCount < MAX_RETRY) {
      await updateRecord<PBRecord>(COLLECTION, params.id, {
        status: "ready",
        retry_count: retryCount + 1,
        error: null,
        completed_at: null,
        claimed_by: null,
        claimed_at: null,
        started_at: null,
      });
      requeued = true;
    }
  }

  return NextResponse.json({ ok: true, task: failed, requeued });
}