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

import { createHttpClient } from "../../src/adapters/http/client.ts";
import { createContractHttpExecutor } from "../../src/adapters/http/http-execution-v3.ts";
import {
  entityQueryKeys,
  TEST_HTTP_CONTRACT,
} from "../helpers/http-contract-fixture.ts";
import { TEST_CREATE_HTTP_CONTRACT } from "../helpers/external-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 },
  );
}

function immediateClock() {
  return { now: () => 0, sleep: async () => {} };
}

function recordingScheduler() {
  const callbacks: Array<() => void> = [];
  return {
    callbacks,
    setTimeout: vi.fn((callback: () => void) => {
      callbacks.push(callback);
      return callbacks.length - 1;
    }),
    clearTimeout: vi.fn(),
  };
}

type HttpDependencies = Parameters<typeof createHttpClient>[0];

function testClient(options: HttpDependencies) {
  return createHttpClient({ ...TEST_HTTP_CONTRACT, ...options });
}

describe("HTTP operation execution contract", () => {
  it("permits a keyless command intent but rejects an unexpected key before dispatch", async () => {
    const attachCredentials = vi.fn(() => ({
      kind: "READY" as const,
      headers: {},
      credentials: "omit" as const,
    }));
    const observedKeys: Array<string | null> = [];
    const fetcher = vi.fn(
      async (_input: RequestInfo | URL, init?: RequestInit) => {
        observedKeys.push(new Headers(init?.headers).get("Idempotency-Key"));
        return Response.json(
          { id: "created", name: "Created" },
          { status: 201 },
        );
      },
    );
    const executor = createContractHttpExecutor({
      baseUrl: "https://api.example/",
      maxRetryAttempts: 0,
      attachCredentials,
      fetcher,
    });
    const nonKeyedCommand = {
      ...TEST_CREATE_HTTP_CONTRACT,
      contract: {
        ...TEST_CREATE_HTTP_CONTRACT.contract,
        retrySemantics: "NEVER" as const,
        commandRecovery: null,
      },
    };
    const scope = Object.freeze({
      generation: 1,
      fingerprint: "scope-1",
      identities: Object.freeze({}) as never,
      signal: new AbortController().signal,
      isCurrent: () => true,
    });
    const intent = Object.freeze({
      intentId: "intent-1",
      operationId: "TEST_CREATE_ENTITY",
      canonicalInputIdentity: "opaque-input-identity",
      createdAtMonotonicMs: 1,
    });

    await expect(
      executor.execute(
        nonKeyedCommand,
        { name: "created" },
        { scope, intent },
      ),
    ).resolves.toMatchObject({ kind: "SUCCESS" });
    expect(observedKeys).toEqual([null]);

    attachCredentials.mockClear();
    fetcher.mockClear();
    await expect(
      executor.execute(
        nonKeyedCommand,
        { name: "created" },
        { scope, intent: { ...intent, idempotencyKey: "unexpected-key" } },
      ),
    ).resolves.toMatchObject({
      kind: "CONTRACT_VIOLATION",
      violation: {
        kind: "UNEXPECTED_IDEMPOTENCY_KEY",
        operation: "REQUEST",
      },
      effect: "NOT_STARTED",
    });
    expect(attachCredentials).not.toHaveBeenCalled();
    expect(fetcher).not.toHaveBeenCalled();
  });

  it("fails auth-required execution before fetch when the session integration is unavailable", async () => {
    const fetcher = vi.fn();
    const client = testClient({
      baseUrl: "https://api.test",
      fetcher,
      authSession: undefined,
    });

    await expect(
      client.execute({ operationId: "LIST_ENTITIES", routeId: "TEST_ROUTE" }),
    ).resolves.toMatchObject({
      ok: false,
      error: { kind: "AUTH_INTEGRATION_FAILURE" },
    });
    expect(fetcher).not.toHaveBeenCalled();
  });

  it("rejects an oversized response without materializing its JSON", async () => {
    const largeOperation = {
      ...TEST_HTTP_CONTRACT.getOperation("LIST_ENTITIES"),
      maxResponseBytes: 32,
      responseMediaTypes: ["application/json"],
      successStatuses: [200],
    };
    const client = testClient({
      baseUrl: "https://api.test",
      getOperation: () => largeOperation,
      fetcher: vi.fn(async () =>
        Response.json({
          success: true,
          data: [{ id: "one", name: "a".repeat(100) }],
          meta: { requestId: "request-1", traceId: "trace-1" },
        }),
      ),
    });

    await expect(client.execute("LIST_ENTITIES")).resolves.toMatchObject({
      ok: false,
      error: { kind: "RESPONSE_BODY_LIMIT" },
    });
  });

  it("sends parsed search/body values and aligns canonical query identity", async () => {
    const requests: Request[] = [];
    const scheduler = recordingScheduler();
    const fetcher = vi.fn(async (input: RequestInfo | URL) => {
      const request = input as Request;
      requests.push(request);
      if (request.method === "POST") {
        return successResponse({ id: "created", name: "Trimmed" });
      }
      return successResponse([]);
    });
    const client = testClient({
      baseUrl: "https://api.test",
      fetcher,
      clock: immediateClock(),
      scheduler,
    });
    const filters = { tags: ["open", "new"], cursor: "a/b", limit: 5 };

    await client.execute({
      operationId: "LIST_ENTITIES",
      routeId: "TEST_ROUTE",
      searchParams: filters,
    });
    await client.execute({
      operationId: "CREATE_ENTITY",
      routeId: "TEST_ROUTE",
      body: { name: "  Trimmed  " },
      idempotencyKey: "logical-command",
    });

    expect(requests[0].url).toBe(
      "https://api.test/api/entities?cursor=a%2Fb&limit=5&tags=open&tags=new",
    );
    expect(requests[0].headers.get("Idempotency-Key")).toBeNull();
    expect(entityQueryKeys.list(filters).at(-1)).toEqual(filters);
    await expect(requests[1].json()).resolves.toEqual({ name: "Trimmed" });
    expect(requests[1].headers.get("Idempotency-Key")).toBe("logical-command");
    expect(requests[1].url).not.toContain("logical-command");
    expect(requests[0].headers.get("X-Correlation-ID")).toBeTruthy();
    expect(requests[0].credentials).toBe("same-origin");
    expect(requests[0].cache).toBe("no-store");
    expect(requests[0].redirect).toBe("error");
    expect(scheduler.setTimeout).toHaveBeenCalledTimes(2);
    expect(scheduler.clearTimeout).toHaveBeenCalledTimes(2);
  });

  it("performs no fetch or timer work for invalid request input", async () => {
    const fetcher = vi.fn();
    const scheduler = recordingScheduler();
    const client = testClient({
      baseUrl: "https://api.test",
      fetcher,
      scheduler,
    });

    await expect(
      client.execute({
        operationId: "CREATE_ENTITY",
        routeId: "TEST_ROUTE",
        body: { name: "   " },
      }),
    ).resolves.toMatchObject({
      ok: false,
      error: { kind: "VALIDATION_REJECTED" },
    });
    expect(fetcher).not.toHaveBeenCalled();
    expect(scheduler.setTimeout).not.toHaveBeenCalled();
    expect(scheduler.clearTimeout).not.toHaveBeenCalled();
  });

  it.each([
    [0, 1],
    [1, 2],
    [2, 3],
  ])(
    "applies runtime max retry count %i as %i total attempts",
    async (maxRetryAttempts, totalAttempts) => {
      const fetcher = vi.fn(async () => failureResponse(503));
      const scheduler = recordingScheduler();
      const client = testClient({
        baseUrl: "https://api.test",
        fetcher,
        clock: immediateClock(),
        scheduler,
        maxRetryAttempts,
      });

      await expect(
        client.execute({
          operationId: "LIST_ENTITIES",
          routeId: "TEST_ROUTE",
        }),
      ).resolves.toMatchObject({
        ok: false,
        error: { kind: "SERVER_FAILURE" },
      });
      expect(fetcher).toHaveBeenCalledTimes(totalAttempts);
      expect(scheduler.setTimeout).toHaveBeenCalledTimes(totalAttempts);
      expect(scheduler.clearTimeout).toHaveBeenCalledTimes(totalAttempts);
    },
  );

  it("distinguishes a runtime timeout from caller navigation abort and cleans listeners", async () => {
    const scheduler = recordingScheduler();
    const fetcher = vi.fn(
      (input: RequestInfo | URL) =>
        new Promise<Response>((_resolve, reject) => {
          (input as Request).signal.addEventListener(
            "abort",
            () => reject(new DOMException("aborted", "AbortError")),
            { once: true },
          );
        }),
    );
    const client = testClient({
      baseUrl: "https://api.test",
      fetcher,
      scheduler,
      maxRetryAttempts: 0,
    });
    const timeoutResult = client.execute({
      operationId: "LIST_ENTITIES",
      routeId: "TEST_ROUTE",
    });
    await vi.waitFor(() => expect(scheduler.callbacks).toHaveLength(1));
    scheduler.callbacks[0]();
    await expect(timeoutResult).resolves.toMatchObject({
      ok: false,
      error: { kind: "REQUEST_TIMEOUT" },
    });

    const caller = new AbortController();
    const add = vi.spyOn(caller.signal, "addEventListener");
    const remove = vi.spyOn(caller.signal, "removeEventListener");
    const abortResult = client.execute({
      operationId: "LIST_ENTITIES",
      routeId: "TEST_ROUTE",
      signal: caller.signal,
    });
    await vi.waitFor(() => expect(fetcher).toHaveBeenCalledTimes(2));
    caller.abort("navigation");
    await expect(abortResult).resolves.toMatchObject({
      ok: false,
      error: { kind: "REQUEST_ABORTED" },
    });
    expect(add).toHaveBeenCalledOnce();
    expect(remove).toHaveBeenCalledOnce();
    expect(scheduler.clearTimeout).toHaveBeenCalledTimes(2);
  });

  it("never retries unsafe, non-retryable status, or schema failures", async () => {
    const unsafeOperation = {
      method: "POST",
      path: "/api/unsafe",
      operationId: "UNSAFE",
      auth: "none",
      timeoutMs: null,
      idempotency: "none",
      retry: "never",
      requestSource: "none",
      requestSchema: "unused",
      responseSchema: "EntityPayload",
      owner: "test",
    } as const;
    const unsafeFetch = vi.fn(async () => failureResponse(503));
    const unsafeClient = testClient({
      baseUrl: "https://api.test",
      fetcher: unsafeFetch,
      clock: immediateClock(),
      getOperation: () => unsafeOperation,
    });
    await unsafeClient.execute({
      operationId: "UNSAFE",
      routeId: "TEST",
    });
    expect(unsafeFetch).toHaveBeenCalledOnce();

    const statusFetch = vi.fn(async () => failureResponse(500));
    const statusClient = testClient({
      baseUrl: "https://api.test",
      fetcher: statusFetch,
      clock: immediateClock(),
    });
    await statusClient.execute({
      operationId: "LIST_ENTITIES",
      routeId: "TEST_ROUTE",
    });
    expect(statusFetch).toHaveBeenCalledOnce();

    const schemaFetch = vi.fn(async () =>
      successResponse([{ id: "one", name: 42 }]),
    );
    const schemaScheduler = recordingScheduler();
    const schemaClient = testClient({
      baseUrl: "https://api.test",
      fetcher: schemaFetch,
      clock: immediateClock(),
      scheduler: schemaScheduler,
    });
    await schemaClient.execute({
      operationId: "LIST_ENTITIES",
      routeId: "TEST_ROUTE",
    });
    expect(schemaFetch).toHaveBeenCalledOnce();
    expect(schemaScheduler.clearTimeout).toHaveBeenCalledOnce();
  });
});