import type { FastifyInstance, FastifyReply, FastifyRequest } from "fastify";
import type Database from "better-sqlite3";
import { getLatestSnapshots, getRecentHistory } from "../db/index.js";

async function requireAuth(req: FastifyRequest, reply: FastifyReply) {
  if (!req.session.username) {
    reply.code(401).send({ error: "not authenticated" });
  }
}

export function registerHostRoutes(app: FastifyInstance, db: Database.Database): void {
  app.get("/api/hosts", { preHandler: requireAuth }, async () => {
    const rows = getLatestSnapshots(db);

    const history = new Map<string, { ts: string; cpuPct: number | null; memPct: number | null; diskPct: number | null }[]>();
    for (const h of getRecentHistory(db)) {
      if (!history.has(h.host_id)) history.set(h.host_id, []);
      history.get(h.host_id)!.push({ ts: h.ts, cpuPct: h.cpu_pct, memPct: h.mem_pct, diskPct: h.disk_pct });
    }

    return {
      hosts: rows.map((r) => ({
        hostId: r.host_id,
        displayName: r.display_name,
        group: r.group_name,
        status: r.status,
        cpuPct: r.cpu_pct,
        memPct: r.mem_pct,
        diskPct: r.disk_pct,
        memTotalBytes: r.mem_total_bytes,
        memUsedBytes: r.mem_used_bytes,
        diskTotalBytes: r.disk_total_bytes,
        diskUsedBytes: r.disk_used_bytes,
        memPressurePct: r.mem_pressure_pct,
        cpuPressurePct: r.cpu_pressure_pct,
        uptimeSec: r.uptime_sec,
        lastSeen: r.ts,
        history: history.get(r.host_id) ?? [],
      })),
    };
  });

  app.get("/api/health", async () => ({ ok: true }));
}