import { describe, expect, it } from "vitest";
import { createAnthropicGuard, createOpenAiGuard, type FetchLike } from "./guard-adapters.js";
import { admitGuardAdapter, type GuardRequest, type Verdict } from "./guard.js";

const model = "guard-model-2026-07-12";
const request: GuardRequest = {
  direction: "outbound",
  source: "alice#1",
  destination: "bob#1",
  text: "meeting at ten",
  policyVersion: "v1",
};
const allow: Verdict = {
  decision: "allow",
  category: "coordination",
  reason: "Routine coordination.",
  model,
  policyVersion: "v1",
};
const modelAllow = {
  decision: "allow",
  category: "coordination",
  reason: "Routine coordination.",
  policyVersion: "v1",
};

describe("guard admission", () => {
  it.each([
    [
      "throws",
      async () => {
        throw new Error("network");
      },
    ],
    ["malformed", async () => "not an object"],
    ["extra fields", async () => ({ ...allow, extra: true })],
    ["wrong model", async () => ({ ...allow, model: "other-model-2026-07-12" })],
  ])("fails closed when raw adapter %s", async (_name, classifyRaw) => {
    const guard = admitGuardAdapter({ providerId: "fake", pinnedModel: model, classifyRaw });
    await expect(guard.classify(request)).resolves.toMatchObject({
      decision: "deny",
      category: "guard_failure",
      model,
    });
  });

  it("fails closed on timeout", async () => {
    const guard = admitGuardAdapter(
      { providerId: "fake", pinnedModel: model, classifyRaw: () => new Promise(() => {}) },
      5,
    );
    await expect(guard.classify(request)).resolves.toMatchObject({
      decision: "deny",
      category: "guard_failure",
    });
  });

  it("rejects floating model aliases at construction", () => {
    expect(() =>
      admitGuardAdapter({
        providerId: "fake",
        pinnedModel: "guard-latest",
        async classifyRaw() {
          return allow;
        },
      }),
    ).toThrow("dated snapshot");
  });

  it("rejects bare family aliases without a documented immutable id", () => {
    expect(() =>
      admitGuardAdapter({
        providerId: "fake",
        pinnedModel: "gpt-5.6",
        async classifyRaw() {
          return allow;
        },
      }),
    ).toThrow("dated snapshot");
  });

  it.each(["gpt-5.6-sol", "gpt-5.6-terra", "gpt-5.6-luna"])(
    "accepts documented immutable undated id %s",
    (pinnedModel) => {
      expect(() =>
        admitGuardAdapter({
          providerId: "fake",
          pinnedModel,
          async classifyRaw() {
            return allow;
          },
        }),
      ).not.toThrow();
    },
  );
});

describe("provider adapters", () => {
  it("uses OpenAI Responses strict JSON schema and accepts a recorded response", async () => {
    let captured: RequestInit | undefined;
    const fetch: FetchLike = async (_url, init) => {
      captured = init;
      return jsonResponse({
        model,
        status: "completed",
        output: [
          { type: "message", content: [{ type: "output_text", text: JSON.stringify(modelAllow) }] },
        ],
      });
    };
    const guard = createOpenAiGuard({ apiKey: "test", pinnedModel: model, fetch });
    await expect(guard.classify(request)).resolves.toEqual(allow);
    const body = JSON.parse(captured!.body as string) as Record<string, any>;
    expect(body).toMatchObject({ model, store: false, background: false, tools: [] });
    expect(body.text.format).toMatchObject({ type: "json_schema", strict: true });
    expect(body.text.format.schema.properties).not.toHaveProperty("model");
    expect(body.text.format.schema.required).not.toContain("model");
    expect(body.instructions).toContain("outbound DLP");
    expect(body.instructions).toContain("Allow ordinary claw-to-claw collaboration");
    expect(body.instructions).toContain("Default to allow when no concrete protected value");
    expect(body.instructions).toContain('Set policyVersion to exactly "v1".');
  });

  it("accepts a recorded Anthropic response with distinct inbound instructions", async () => {
    let captured: RequestInit | undefined;
    const fetch: FetchLike = async (_url, init) => {
      captured = init;
      return jsonResponse({
        model,
        stop_reason: "end_turn",
        content: [{ type: "text", text: JSON.stringify({ ...modelAllow, category: "safe" }) }],
      });
    };
    const guard = createAnthropicGuard({ apiKey: "test", pinnedModel: model, fetch });
    const inbound = { ...request, direction: "inbound" as const };
    await expect(guard.classify(inbound)).resolves.toMatchObject({
      decision: "allow",
      category: "safe",
    });
    const body = JSON.parse(captured!.body as string) as Record<string, any>;
    expect(body.system).toContain("inbound prompt-injection");
    expect(body.system).toContain("task requests");
    expect(body.system).toContain("a request to collaborate is not steering by itself");
    expect(body.system).toContain('Set policyVersion to exactly "v1".');
    expect(body.system).not.toContain('"model"');
    expect(body.output_config.format.type).toBe("json_schema");
    expect(body.output_config.format.schema).toMatchObject({
      additionalProperties: false,
      required: ["decision", "category", "reason", "policyVersion"],
    });
    expect(body.output_config.format.schema.properties).not.toHaveProperty("model");
    expect((captured!.headers as Record<string, string>)["anthropic-version"]).toBe("2023-06-01");
  });

  it("fails closed on Anthropic prose despite provider schema enforcement", async () => {
    const guard = createAnthropicGuard({
      apiKey: "test",
      pinnedModel: model,
      fetch: async () =>
        jsonResponse({
          model,
          stop_reason: "end_turn",
          content: [{ type: "text", text: `Verdict: ${JSON.stringify(modelAllow)}` }],
        }),
    });
    await expect(guard.classify(request)).resolves.toMatchObject({
      decision: "deny",
      category: "guard_failure",
    });
  });

  it.each([
    [
      "OpenAI",
      (fetch: FetchLike) => createOpenAiGuard({ apiKey: "test", pinnedModel: model, fetch }),
    ],
    [
      "Anthropic",
      (fetch: FetchLike) => createAnthropicGuard({ apiKey: "test", pinnedModel: model, fetch }),
    ],
  ])(
    "cancels %s non-200 provider response bodies before failing closed",
    async (_name, createGuard) => {
      let cancelled = false;
      const response = new Response(
        new ReadableStream<Uint8Array>({
          start(controller) {
            controller.enqueue(new TextEncoder().encode("partial error body"));
          },
          cancel() {
            cancelled = true;
          },
        }),
        { status: 503 },
      );
      const guard = createGuard(async () => response);

      await expect(guard.classify(request)).resolves.toMatchObject({
        decision: "deny",
        category: "guard_failure",
      });
      expect(cancelled).toBe(true);
    },
  );

  it("cancels oversized provider response streams before buffering them fully", async () => {
    const maxBytes = 256 * 1024;
    const chunk = new TextEncoder().encode("x".repeat(64 * 1024));
    const totalChunks = 64;
    let emittedChunks = 0;
    let cancelled = false;
    const response = new Response(
      new ReadableStream<Uint8Array>({
        pull(controller) {
          if (emittedChunks >= totalChunks) {
            controller.close();
            return;
          }
          controller.enqueue(chunk);
          emittedChunks += 1;
        },
        cancel() {
          cancelled = true;
        },
      }),
      { headers: { "content-type": "application/json" } },
    );
    const guard = createOpenAiGuard({
      apiKey: "test",
      pinnedModel: model,
      fetch: async () => response,
    });

    await expect(guard.classify(request)).resolves.toMatchObject({
      decision: "deny",
      category: "guard_failure",
    });
    expect(cancelled).toBe(true);
    // Allow the overflow chunk plus one chunk queued by the stream implementation.
    expect(emittedChunks * chunk.byteLength).toBeLessThanOrEqual(maxBytes + chunk.byteLength * 2);
  });

  it("accepts valid provider responses close to the body limit", async () => {
    const body = JSON.stringify({
      model,
      status: "completed",
      output: [
        { type: "message", content: [{ type: "output_text", text: JSON.stringify(modelAllow) }] },
      ],
      provider_metadata: "x".repeat(240 * 1024),
    });
    const bodyBytes = new TextEncoder().encode(body).byteLength;
    expect(bodyBytes).toBeGreaterThan(240 * 1024);
    expect(bodyBytes).toBeLessThan(256 * 1024);
    const guard = createOpenAiGuard({
      apiKey: "test",
      pinnedModel: model,
      fetch: async () => new Response(body, { headers: { "content-type": "application/json" } }),
    });

    await expect(guard.classify(request)).resolves.toEqual(allow);
  });

  it("fails closed on malformed JSON and provider model mismatch", async () => {
    const malformed = createOpenAiGuard({
      apiKey: "test",
      pinnedModel: model,
      fetch: async () => new Response("not json"),
    });
    await expect(malformed.classify(request)).resolves.toMatchObject({ category: "guard_failure" });
    const mismatch = createOpenAiGuard({
      apiKey: "test",
      pinnedModel: model,
      fetch: async () =>
        jsonResponse({ model: "other-model-2026-07-12", status: "completed", output: [] }),
    });
    await expect(mismatch.classify(request)).resolves.toMatchObject({ category: "guard_failure" });
    const duplicate = createOpenAiGuard({
      apiKey: "test",
      pinnedModel: model,
      fetch: async () =>
        jsonResponse({
          model,
          status: "completed",
          output: [
            {
              type: "message",
              content: [
                {
                  type: "output_text",
                  text: '{"decision":"allow","decision":"deny","category":"safe","reason":"No.","policyVersion":"v1"}',
                },
              ],
            },
          ],
        }),
    });
    await expect(duplicate.classify(request)).resolves.toMatchObject({ category: "guard_failure" });
  });

  it("takes model evidence from the provider and requires the model policy echo", async () => {
    const responseFor =
      (modelJson: unknown): FetchLike =>
      async () =>
        jsonResponse({
          model,
          status: "completed",
          output: [
            {
              type: "message",
              content: [{ type: "output_text", text: JSON.stringify(modelJson) }],
            },
          ],
        });
    const happy = createOpenAiGuard({
      apiKey: "test",
      pinnedModel: model,
      fetch: responseFor(modelAllow),
    });
    await expect(happy.classify(request)).resolves.toEqual(allow);
    const wrongPolicy = createOpenAiGuard({
      apiKey: "test",
      pinnedModel: model,
      fetch: responseFor({ ...modelAllow, policyVersion: "v2" }),
    });
    await expect(wrongPolicy.classify(request)).resolves.toMatchObject({
      decision: "deny",
      category: "guard_failure",
    });
    const { policyVersion: _policyVersion, ...missingPolicyJson } = modelAllow;
    const missingPolicy = createOpenAiGuard({
      apiKey: "test",
      pinnedModel: model,
      fetch: responseFor(missingPolicyJson),
    });
    await expect(missingPolicy.classify(request)).resolves.toMatchObject({
      decision: "deny",
      category: "guard_failure",
    });
    const unexpectedModel = createOpenAiGuard({
      apiKey: "test",
      pinnedModel: model,
      fetch: responseFor({ ...modelAllow, model: "invented-2026-01-01" }),
    });
    await expect(unexpectedModel.classify(request)).resolves.toMatchObject({
      decision: "deny",
      category: "guard_failure",
    });
  });
});

function jsonResponse(value: unknown, status = 200): Response {
  return new Response(JSON.stringify(value), {
    status,
    headers: { "content-type": "application/json" },
  });
}