import type { FastifyInstance } from "fastify";
import os from "node:os";
import { pingDb } from "@spinza/database";
import { CryptoRng, runSpin } from "@spinza/game-core";
import { GAMES } from "@spinza/games";
import { pingRedis, redis } from "../lib/redis";
import { config } from "../config";
import { maintenance } from "../lib/settings";

const startedAt = Date.now();

export async function healthRoutes(app: FastifyInstance) {
  app.get("/api/health", async () => ({
    status: "ok",
    service: "spinza-api",
    version: config.version,
    uptime: Math.round((Date.now() - startedAt) / 1000),
    node: os.hostname(),
    maintenance: maintenance().enabled,
    time: new Date().toISOString(),
  }));

  app.get("/api/health/database", async (reply) => {
    try {
      const latency = await pingDb();
      return { status: "ok", latencyMs: latency };
    } catch (e) {
      return { status: "down", error: (e as Error).message };
    }
  });

  app.get("/api/health/redis", async () => {
    try {
      const latency = await pingRedis();
      return { status: "ok", latencyMs: latency };
    } catch (e) {
      return { status: "down", error: (e as Error).message };
    }
  });

  app.get("/api/health/game-engine", async () => {
    const t = Date.now();
    const def = GAMES[0];
    const out = runSpin(def, 100, { rng: new CryptoRng() });
    return { status: "ok", games: GAMES.length, sampleGame: def.slug, steps: out.steps.length, latencyMs: Date.now() - t };
  });

  app.get("/api/ready", async (_req, reply) => {
    try {
      await Promise.all([pingDb(), pingRedis()]);
      return { ready: true };
    } catch (e) {
      reply.code(503);
      return { ready: false, error: (e as Error).message };
    }
  });

  app.get("/api/live", async () => {
    const cutoff = Date.now() - 5 * 60_000;
    const players = await redis().zcount("live:players", cutoff, "+inf");
    return { players };
  });
}