import { describe, expect, it, vi } from "vitest";

import { createHttpClient } from "../../src/adapters/http/client.ts";
import type { DiagnosticRecordInput } from "../../src/contracts/diagnostics.ts";
import { TEST_HTTP_CONTRACT } from "../helpers/http-contract-fixture.ts";

function successResponse(data: unknown) {
  return Response.json({
    success: true,
    data,
    meta: { requestId: "request-1", traceId: "trace-1" },
  });
}

function failureResponse(status: number) {
  return Response.json(
    {
      success: false,
      error: { code: "TEMPORARY" },
      meta: { requestId: "request-1", traceId: "trace-1" },
    },
    { status },
  );
}

type EmittedEvent = Readonly<{
  eventName: string;
  attributes: Readonly<Record<string, unknown>>;
}>;

function harness(fetcher: typeof fetch, maxRetryAttempts = 1) {
  const records: DiagnosticRecordInput[] = [];
  const emitted: EmittedEvent[] = [];
  let currentTime = 0;
  const client = createHttpClient({
    ...TEST_HTTP_CONTRACT,
    baseUrl: "https://api.test",
    fetcher,
    maxRetryAttempts,
    clock: {
      now: () => currentTime,
      sleep: async () => {
        currentTime += 150;
      },
    },
    scheduler: {
      setTimeout: () => 1,
      clearTimeout: () => {},
    },
    correlationIdFactory: () => "correlation-fixed",
    diagnostics: {
      record(input) {
        records.push(structuredClone(input));
      },
    },
    telemetry: {
      emit(eventName, attributes) {
        emitted.push({
          eventName,
          attributes: structuredClone(attributes),
        });
      },
    },
  });
  return { client, records, emitted };
}

describe("HTTP diagnostics and terminal telemetry", () => {
  it("records one successful reference route outcome and no failure event", async () => {
    const { client, records, emitted } = harness(
      vi.fn(async () => successResponse([])),
    );

    await expect(
      client.execute({
        operationId: "LIST_ENTITIES",
        routeId: "TEST_ROUTE",
      }),
    ).resolves.toMatchObject({ ok: true });

    expect(records).toEqual([
      {
        level: "info",
        eventId: "http.request.completed",
        context: {
          route_id: "TEST_ROUTE",
          operation_id: "LIST_ENTITIES",
          correlation_id: "correlation-fixed",
          outcome: "success",
          error_kind: "NONE",
          http_status_group: "2xx",
          attempt_count_bucket: "1",
          duration_bucket: "lt100ms",
        },
      },
    ]);
    expect(emitted).toEqual([]);
  });

  it("summarizes retry recovery once without a terminal failure event", async () => {
    const fetcher = vi
      .fn<typeof fetch>()
      .mockResolvedValueOnce(failureResponse(503))
      .mockResolvedValueOnce(successResponse([]));
    const { client, records, emitted } = harness(fetcher);

    await expect(
      client.execute({
        operationId: "LIST_ENTITIES",
        routeId: "TEST_ROUTE",
      }),
    ).resolves.toMatchObject({ ok: true });

    expect(fetcher).toHaveBeenCalledTimes(2);
    expect(records).toHaveLength(1);
    expect(records[0]).toMatchObject({
      eventId: "http.request.completed",
      context: {
        outcome: "recovered",
        correlation_id: "correlation-fixed",
        duration_bucket: "100-499ms",
      },
    });
    expect(emitted).toEqual([]);
  });

  it("emits one bounded terminal failure after all attempts", async () => {
    const fetcher = vi.fn(async () => failureResponse(503));
    const { client, records, emitted } = harness(fetcher);

    await expect(
      client.execute({
        operationId: "CREATE_ENTITY",
        routeId: "TEST_ROUTE",
        body: { name: "private user input" },
        idempotencyKey: "private-idempotency-key",
      }),
    ).resolves.toMatchObject({
      ok: false,
      error: { kind: "SERVER_FAILURE" },
    });

    expect(fetcher).toHaveBeenCalledTimes(2);
    expect(records).toHaveLength(1);
    expect(emitted).toEqual([
      {
        eventName: "api.request.failed",
        attributes: {
          error_kind: "SERVER_FAILURE",
          http_status_group: "5xx",
          attempt_count_bucket: "2",
          route_id: "TEST_ROUTE",
          operation_id: "CREATE_ENTITY",
          duration_bucket: "100-499ms",
        },
      },
    ]);
    expect(JSON.stringify({ records, emitted })).not.toMatch(
      /private user input|private-idempotency-key/,
    );
  });

  it("records navigation abort without failure telemetry", async () => {
    const caller = new AbortController();
    caller.abort("navigation");
    const fetcher = vi.fn(async (request: RequestInfo | URL) => {
      const signal = (request as Request).signal;
      if (signal.aborted) throw new DOMException("aborted", "AbortError");
      return successResponse([]);
    });
    const { client, records, emitted } = harness(
      fetcher as unknown as typeof fetch,
    );

    await expect(
      client.execute({
        operationId: "LIST_ENTITIES",
        routeId: "TEST_ROUTE",
        signal: caller.signal,
      }),
    ).resolves.toMatchObject({
      ok: false,
      error: { kind: "REQUEST_ABORTED" },
    });

    expect(records).toHaveLength(1);
    expect(records[0]).toMatchObject({
      eventId: "http.request.completed",
      context: { outcome: "aborted", error_kind: "REQUEST_ABORTED" },
    });
    expect(emitted).toEqual([]);
  });
});