import { invalidateProjects, projectRef } from "@/lib/projects";
import { readManifest } from "@/lib/projects/report.mjs";
import { diffManifests } from "@/lib/report/manifest-diff.mjs";
import { createSnapshot, listSnapshots, readSnapshot } from "@/lib/report/snapshots.mjs";

export const dynamic = "force-dynamic";

// GET  ?project=<id>                  every snapshot, newest first
// GET  ?project=<id>&diff=<rel>       that snapshot diffed against the current manifest
// POST { project, label? }            copy the manifest into revisions/
export async function GET(request: Request) {
  const url = new URL(request.url);
  const project = await projectRef(url.searchParams.get("project") ?? "");
  if (!project) return Response.json({ error: "no such project" }, { status: 404 });
  const headers = { "cache-control": "no-store" };
  const rel = url.searchParams.get("diff");
  if (rel) {
    try {
      const [before, after] = await Promise.all([readSnapshot(project.dir, rel), readManifest(project.dir)]);
      return Response.json({ snapshot: rel, ...diffManifests(before, after) }, { headers });
    } catch (e) {
      return Response.json({ error: e instanceof Error ? e.message : String(e) }, { status: 400 });
    }
  }
  return Response.json({ snapshots: await listSnapshots(project.dir) }, { headers });
}

export async function POST(request: Request) {
  const body = (await request.json().catch(() => ({}))) as { project?: string; label?: string | null };
  const project = await projectRef(String(body.project ?? ""));
  if (!project) return Response.json({ error: "no such project" }, { status: 404 });
  try {
    const r = await createSnapshot(project.dir, { label: body.label ? String(body.label) : null });
    invalidateProjects();
    return Response.json({ ok: true, ...r }, { headers: { "cache-control": "no-store" } });
  } catch (e) {
    return Response.json({ error: e instanceof Error ? e.message : String(e) }, { status: 400 });
  }
}