/**
 * Integration tests for ScenarioRunStepEntity.output column and the
 * helpers.getStepOutput() API available inside exec step scripts.
 *
 * Strategy:
 * - Seed a session row so the scheduler can create a browser context.
 * - Create a scenario + steps with controlled return values.
 * - Call ScenarioSchedulerService.pickUpPendingRuns() directly to process
 *   the run synchronously (no real timers needed).
 * - Assert step-run output persisted and getStepOutput() returns it.
 */

import { INestApplication } from "@nestjs/common";
import { DataSource } from "typeorm";
import { buildTestApp } from "./app.harness";
import { ScenarioService } from "../src/scenario/scenario.service";
import { ScenarioSchedulerService } from "../src/scenario/scenario-scheduler.service";

describe("ScenarioRunStepEntity.output + helpers.getStepOutput", () => {
  let app: INestApplication;
  let dataSource: DataSource;
  let scenarioService: ScenarioService;
  let scheduler: ScenarioSchedulerService;

  beforeAll(async () => {
    app = await buildTestApp();
    dataSource = app.get(DataSource);
    scenarioService = app.get(ScenarioService);
    scheduler = app.get(ScenarioSchedulerService);
  });

  afterAll(async () => {
    await app.close();
  });

  /** Seed a minimal session so the scheduler can open a browser context. */
  async function seedSession(name = "output-test-session"): Promise<void> {
    await dataSource.query(
      `INSERT OR IGNORE INTO sessions (sessionName, token, cookies, localStorage)
       VALUES ('${name}', 'tok', '[]', '{}')`,
    );
  }

  /** Create a scenario and return its id. */
  async function createScenario(name = "output-scenario"): Promise<string> {
    const sc = await scenarioService.create({ name });
    return sc.id;
  }

  /** Create a step and return its id. */
  async function createStep(
    scenarioId: string,
    _order: number,
    execCode: string,
    sessionName = "output-test-session",
  ): Promise<string> {
    const step = await scenarioService.createStep(scenarioId, {
      sessionName,
      execCode,
    });
    return step.id;
  }

  /** Trigger a run and process it to completion via the scheduler. */
  async function runScenario(scenarioId: string): Promise<string> {
    const run = await scenarioService.createRun(scenarioId);
    // Drive the scheduler directly — keeps tests synchronous and fast.
    await scheduler.pickUpPendingRuns();
    // Wait for the run to reach a terminal state (max 10 s).
    const result = await scenarioService.waitForRun(scenarioId, run.id, 10_000);
    return result.id;
  }

  // ── output column ──────────────────────────────────────────────────────────

  describe("output column", () => {
    it("stores the return value of an exec script as JSON", async () => {
      await seedSession();
      const scId = await createScenario("output-basic");
      await createStep(scId, 0, "return 42;");

      const runId = await runScenario(scId);

      const row = await dataSource.query(
        `SELECT output, status FROM scenario_run_steps WHERE runId = '${runId}'`,
      );
      expect(row[0].status).toBe("pass");
      expect(JSON.parse(row[0].output as string)).toBe(42);
    });

    it("stores object return values as JSON", async () => {
      await seedSession();
      const scId = await createScenario("output-object");
      await createStep(scId, 0, 'return { foo: "bar", n: 7 };');

      const runId = await runScenario(scId);

      const row = await dataSource.query(
        `SELECT output FROM scenario_run_steps WHERE runId = '${runId}'`,
      );
      expect(JSON.parse(row[0].output as string)).toEqual({ foo: "bar", n: 7 });
    });

    it("stores null when the script returns undefined/nothing", async () => {
      await seedSession();
      const scId = await createScenario("output-undefined");
      await createStep(scId, 0, "const x = 1;");

      const runId = await runScenario(scId);

      const row = await dataSource.query(
        `SELECT output FROM scenario_run_steps WHERE runId = '${runId}'`,
      );
      expect(row[0].output).toBeNull();
    });

    it("output is exposed on the stepRuns inside GET /scenarios/:id/run/:runId via findRun", async () => {
      await seedSession();
      const scId = await createScenario("output-findrun");
      await createStep(scId, 0, "return 'hello';");

      const runId = await runScenario(scId);
      const run = await scenarioService.findRun(scId, runId);

      expect(run.stepRuns[0].output).toBe(JSON.stringify("hello"));
    });
  });

  // ── helpers.getStepOutput ──────────────────────────────────────────────────

  describe("helpers.getStepOutput()", () => {
    it("returns output of a previous step by absolute order", async () => {
      await seedSession();
      const scId = await createScenario("getStepOutput-absolute");
      await createStep(scId, 0, "return 99;");
      // Step 1 reads step 0's output via absolute index 0
      await createStep(scId, 1, "return await helpers.getStepOutput(0);");

      const runId = await runScenario(scId);
      const rows = await dataSource.query(
        `SELECT "order", output FROM scenario_run_steps WHERE runId = '${runId}' ORDER BY "order"`,
      );

      expect(JSON.parse(rows[0].output as string)).toBe(99);
      expect(JSON.parse(rows[1].output as string)).toBe(99);
    });

    it("returns output of the previous step using relative index -1", async () => {
      await seedSession();
      const scId = await createScenario("getStepOutput-relative");
      await createStep(scId, 0, 'return "step-zero";');
      // Step 1 uses relative index -1 to reference step 0
      await createStep(scId, 1, "return await helpers.getStepOutput(-1);");

      const runId = await runScenario(scId);
      const rows = await dataSource.query(
        `SELECT "order", output FROM scenario_run_steps WHERE runId = '${runId}' ORDER BY "order"`,
      );

      expect(JSON.parse(rows[1].output as string)).toBe("step-zero");
    });

    it("returns null for a step that does not exist", async () => {
      await seedSession();
      const scId = await createScenario("getStepOutput-missing");
      // Step 0 tries to read step order 99 which does not exist
      await createStep(scId, 0, "return await helpers.getStepOutput(99);");

      const runId = await runScenario(scId);
      const row = await dataSource.query(
        `SELECT output FROM scenario_run_steps WHERE runId = '${runId}'`,
      );

      expect(row[0].output).toBeNull();
    });

    it("chains output across three steps", async () => {
      await seedSession();
      const scId = await createScenario("getStepOutput-chain");
      await createStep(scId, 0, "return [1, 2];");
      await createStep(
        scId,
        1,
        "const prev = await helpers.getStepOutput(-1); return [...prev, 3];",
      );
      await createStep(
        scId,
        2,
        "const prev = await helpers.getStepOutput(-1); return [...prev, 4];",
      );

      const runId = await runScenario(scId);
      const rows = await dataSource.query(
        `SELECT "order", output FROM scenario_run_steps WHERE runId = '${runId}' ORDER BY "order"`,
      );

      expect(JSON.parse(rows[0].output as string)).toEqual([1, 2]);
      expect(JSON.parse(rows[1].output as string)).toEqual([1, 2, 3]);
      expect(JSON.parse(rows[2].output as string)).toEqual([1, 2, 3, 4]);
    });
  });
});