import { createServer, type IncomingMessage, type Server, type ServerResponse } from "node:http";
import { describe, expect, it } from "vitest";
import { OriginClient } from "../src/client.js";

function withServer(
  handler: (req: IncomingMessage, res: ServerResponse) => void,
): Promise<{ server: Server; url: string }> {
  return new Promise((resolve) => {
    const server = createServer(handler);
    server.listen(0, "127.0.0.1", () => {
      const address = server.address();
      const port = typeof address === "object" && address ? address.port : 0;
      resolve({ server, url: `http://127.0.0.1:${port}` });
    });
  });
}

describe("OriginClient", () => {
  it("requires serviceKey/type/version/name", () => {
    expect(() => new OriginClient({ serviceKey: "", type: "", version: "", name: "" })).toThrow();
  });

  it("sends the expected payload and headers on checkinOnce", async () => {
    let gotKey = "";
    let gotBody: Record<string, unknown> = {};
    const { server, url } = await withServer((req, res) => {
      gotKey = req.headers["x-origin-service-key"] as string;
      let raw = "";
      req.on("data", (chunk) => {
        raw += chunk;
      });
      req.on("end", () => {
        gotBody = JSON.parse(raw);
        res.writeHead(200, { "Content-Type": "application/json" });
        res.end(
          JSON.stringify({
            success: true,
            service_instance_id: 42,
            unique_install_id: gotBody.unique_install_id,
            status: "provisioning",
            pinged_at: "2026-08-01T00:00:00Z",
          }),
        );
      });
    });

    try {
      const client = new OriginClient({
        url,
        serviceKey: "test-key",
        type: "icy2",
        version: "v1.0.0",
        name: "icy2-test",
        installId: "test-install-id",
      });

      const resp = await client.checkinOnce();

      expect(gotKey).toBe("test-key");
      expect(gotBody.type).toBe("icy2");
      expect(gotBody.name).toBe("icy2-test");
      expect(gotBody.unique_install_id).toBe("test-install-id");
      expect(resp.success).toBe(true);
      expect(resp.service_instance_id).toBe(42);
    } finally {
      server.close();
    }
  });

  it("throws on a non-2xx response", async () => {
    const { server, url } = await withServer((_req, res) => {
      res.writeHead(500);
      res.end();
    });

    try {
      const client = new OriginClient({
        url,
        serviceKey: "test-key",
        type: "icy2",
        version: "v1.0.0",
        name: "icy2-test",
        installId: "test-install-id",
      });

      await expect(client.checkinOnce()).rejects.toThrow();
    } finally {
      server.close();
    }
  });

  it("does not throw for an unreachable server", async () => {
    const client = new OriginClient({
      url: "http://127.0.0.1:1",
      serviceKey: "test-key",
      type: "icy2",
      version: "v1.0.0",
      name: "icy2-test",
      installId: "test-install-id",
    });

    await expect(client.checkinOnce()).rejects.toThrow();
  });

  it("start() checks in immediately and stop() prevents further calls", async () => {
    let calls = 0;
    const { server, url } = await withServer((_req, res) => {
      calls += 1;
      res.writeHead(200, { "Content-Type": "application/json" });
      res.end(
        JSON.stringify({
          success: true,
          service_instance_id: 1,
          unique_install_id: "x",
          status: "provisioning",
          pinged_at: "2026-08-01T00:00:00Z",
        }),
      );
    });

    try {
      const client = new OriginClient({
        url,
        serviceKey: "test-key",
        type: "icy2",
        version: "v1.0.0",
        name: "icy2-test",
        installId: "test-install-id",
        intervalHours: 24,
      });

      client.start();
      await new Promise((resolve) => setTimeout(resolve, 50));
      client.stop();

      expect(calls).toBe(1);
    } finally {
      server.close();
    }
  });
});