import { describe, expect, it, beforeEach, afterEach, vi } from "vitest";
import { handleToolCall } from "../src/mcp/standalone.js";
import { resetHandleForTests } from "../src/mcp/rest-proxy.js";
import { InMemoryKV } from "../src/mcp/in-memory-kv.js";

type FetchMock = ReturnType<typeof vi.fn>;

function installFetch(handler: (url: string, init?: RequestInit) => Response): FetchMock {
  const fn = vi.fn(async (url: string | URL, init?: RequestInit) =>
    handler(url.toString(), init),
  );
  (globalThis as { fetch: typeof fetch }).fetch = fn as unknown as typeof fetch;
  return fn;
}

const BASE = "http://localhost:3111";

describe("@agentmemory/mcp standalone — server proxy (issue #159)", () => {
  const originalFetch = globalThis.fetch;

  beforeEach(() => {
    resetHandleForTests();
    process.env["AGENTMEMORY_URL"] = BASE;
    delete process.env["AGENTMEMORY_SECRET"];
  });

  afterEach(() => {
    resetHandleForTests();
    globalThis.fetch = originalFetch;
    delete process.env["AGENTMEMORY_URL"];
  });

  it("proxies memory_sessions to GET /agentmemory/sessions when server is up", async () => {
    const calls: Array<{ url: string; method: string }> = [];
    installFetch((url, init) => {
      calls.push({ url, method: init?.method || "GET" });
      if (url.endsWith("/agentmemory/livez")) {
        return new Response("ok", { status: 200 });
      }
      if (url.includes("/agentmemory/sessions")) {
        return new Response(
          JSON.stringify({ sessions: [{ id: "sess-1", observations: 69 }] }),
          { status: 200, headers: { "content-type": "application/json" } },
        );
      }
      return new Response("not found", { status: 404 });
    });

    const res = await handleToolCall("memory_sessions", { limit: 5 });
    const body = JSON.parse(res.content[0].text);
    expect(body.sessions).toHaveLength(1);
    expect(body.sessions[0].id).toBe("sess-1");
    expect(calls.find((c) => c.url.includes("/sessions"))).toBeDefined();
  });

  it("proxies memory_smart_search to POST /agentmemory/smart-search", async () => {
    installFetch((url, init) => {
      if (url.endsWith("/agentmemory/livez")) return new Response("ok", { status: 200 });
      if (url.endsWith("/agentmemory/smart-search")) {
        const body = JSON.parse((init?.body as string) || "{}");
        return new Response(
          JSON.stringify({
            mode: "compact",
            query: body.query,
            results: [{ id: "m1", score: 0.9 }],
          }),
          { status: 200 },
        );
      }
      return new Response("", { status: 404 });
    });
    const res = await handleToolCall("memory_smart_search", { query: "auth bug", limit: 5 });
    const body = JSON.parse(res.content[0].text);
    expect(body.query).toBe("auth bug");
    expect(body.results[0].id).toBe("m1");
  });

  it("proxies memory_recall to POST /agentmemory/search and forwards format/token_budget (#507)", async () => {
    const calls: Array<{ url: string; body?: unknown }> = [];
    installFetch((url, init) => {
      if (url.endsWith("/agentmemory/livez")) return new Response("ok", { status: 200 });
      const body = init?.body ? JSON.parse(init.body as string) : undefined;
      calls.push({ url, body });
      if (url.endsWith("/agentmemory/search")) {
        return new Response(
          JSON.stringify({
            mode: "full",
            facts: [{ id: "m1" }],
            narrative: "n",
            concepts: ["c"],
            files: ["f"],
          }),
          { status: 200, headers: { "content-type": "application/json" } },
        );
      }
      return new Response("not found", { status: 404 });
    });
    const res = await handleToolCall("memory_recall", {
      query: "auth bug",
      limit: 5,
      format: "full",
      token_budget: 800,
    });
    const body = JSON.parse(res.content[0].text);
    expect(body.mode).toBe("full");
    expect(body.facts[0].id).toBe("m1");
    const searchCall = calls.find((c) => c.url.endsWith("/agentmemory/search"));
    expect(searchCall).toBeDefined();
    expect(searchCall?.body).toEqual({
      query: "auth bug",
      limit: 5,
      format: "full",
      token_budget: 800,
    });
    expect(calls.find((c) => c.url.endsWith("/agentmemory/smart-search"))).toBeUndefined();
  });

  it("memory_recall defaults format to 'full' when omitted (#507)", async () => {
    let recallBody: Record<string, unknown> | undefined;
    installFetch((url, init) => {
      if (url.endsWith("/agentmemory/livez")) return new Response("ok", { status: 200 });
      if (url.endsWith("/agentmemory/search")) {
        recallBody = init?.body ? JSON.parse(init.body as string) : undefined;
        return new Response(JSON.stringify({ mode: "full", facts: [] }), { status: 200 });
      }
      return new Response("not found", { status: 404 });
    });
    await handleToolCall("memory_recall", { query: "x" });
    expect(recallBody?.["format"]).toBe("full");
    expect(recallBody).not.toHaveProperty("token_budget");
  });

  it("proxies memory_governance_delete to the DELETE REST endpoint", async () => {
    const calls: Array<{ url: string; method: string; body?: unknown }> = [];
    installFetch((url, init) => {
      const method = init?.method || "GET";
      if (url.endsWith("/agentmemory/livez")) return new Response("ok", { status: 200 });
      calls.push({
        url,
        method,
        body: init?.body ? JSON.parse(init.body as string) : undefined,
      });
      if (url.endsWith("/agentmemory/governance/memories") && method === "DELETE") {
        return new Response(JSON.stringify({ success: true, deleted: 2 }), {
          status: 200,
          headers: { "content-type": "application/json" },
        });
      }
      return new Response("method not allowed", { status: 405, statusText: "Method Not Allowed" });
    });

    const res = await handleToolCall("memory_governance_delete", {
      memoryIds: "mem_1, mem_2",
      reason: "cleanup stale test data",
    });

    expect(JSON.parse(res.content[0].text)).toEqual({ success: true, deleted: 2 });
    expect(calls).toEqual([
      {
        url: `${BASE}/agentmemory/governance/memories`,
        method: "DELETE",
        body: {
          memoryIds: ["mem_1", "mem_2"],
          reason: "cleanup stale test data",
        },
      },
    ]);
  });

  it("local fallback returns the same shape as proxy for memory_smart_search", async () => {
    installFetch(() => {
      throw new Error("ECONNREFUSED");
    });
    const localKv = new InMemoryKV(undefined);
    await handleToolCall("memory_save", { content: "shape-check entry" }, localKv);
    const res = await handleToolCall("memory_smart_search", { query: "shape" }, localKv);
    const body = JSON.parse(res.content[0].text);
    expect(body).toHaveProperty("mode", "compact");
    expect(Array.isArray(body.results)).toBe(true);
    expect(body.results[0].content).toBe("shape-check entry");
  });

  it("attaches Bearer token on the proxied tool request, not just the probe", async () => {
    process.env["AGENTMEMORY_SECRET"] = "s3cret";
    const authByPath = new Map<string, string | undefined>();
    installFetch((url, init) => {
      const auth = (init?.headers as Record<string, string> | undefined)?.[
        "authorization"
      ];
      const u = new URL(url);
      authByPath.set(u.pathname, auth);
      if (url.endsWith("/agentmemory/livez")) return new Response("ok", { status: 200 });
      return new Response(JSON.stringify({ sessions: [] }), { status: 200 });
    });
    await handleToolCall("memory_sessions", {});
    expect(authByPath.get("/agentmemory/livez")).toBe("Bearer s3cret");
    expect(authByPath.get("/agentmemory/sessions")).toBe("Bearer s3cret");
  });

  it("falls back to local InMemoryKV when server is unreachable", async () => {
    installFetch(() => {
      throw new Error("ECONNREFUSED");
    });
    const localKv = new InMemoryKV(undefined);
    await handleToolCall("memory_save", { content: "local only" }, localKv);
    const recall = await handleToolCall("memory_recall", { query: "local" }, localKv);
    const out = JSON.parse(recall.content[0].text);
    expect(out.mode).toBe("compact");
    expect(out.results).toHaveLength(1);
    expect(out.results[0].content).toBe("local only");
  });

  it("invalidates the handle on proxy failure, so the next call re-probes", async () => {
    let probeCount = 0;
    let serverUp = true;
    installFetch((url) => {
      if (url.endsWith("/agentmemory/livez")) {
        probeCount++;
        return serverUp ? new Response("ok", { status: 200 }) : new Response("", { status: 500 });
      }
      return new Response("boom", { status: 500, statusText: "Internal Server Error" });
    });
    const localKv = new InMemoryKV(undefined);
    await handleToolCall("memory_save", { content: "first fallback" }, localKv);
    expect(probeCount).toBe(1);
    serverUp = false;
    await handleToolCall("memory_save", { content: "second fallback" }, localKv);
    expect(probeCount).toBe(2);
  });

  it("forwards non-essential tools to /agentmemory/mcp/call (#234)", async () => {
    const calls: Array<{ url: string; body?: unknown }> = [];
    installFetch((url, init) => {
      if (url.endsWith("/agentmemory/livez")) {
        return new Response("ok", { status: 200 });
      }
      if (url.endsWith("/agentmemory/mcp/call")) {
        const body = init?.body ? JSON.parse(init.body as string) : null;
        calls.push({ url, body });
        return new Response(
          JSON.stringify({
            content: [
              {
                type: "text",
                text: JSON.stringify({ saved: "lesson_xyz" }),
              },
            ],
          }),
          { status: 200, headers: { "content-type": "application/json" } },
        );
      }
      return new Response("not found", { status: 404 });
    });

    const res = await handleToolCall("memory_lesson_save", {
      title: "Always pin lockfiles",
      content: "...",
    });
    const body = JSON.parse(res.content[0].text);
    expect(body.saved).toBe("lesson_xyz");
    expect(calls).toHaveLength(1);
    expect(calls[0].body).toEqual({
      name: "memory_lesson_save",
      arguments: { title: "Always pin lockfiles", content: "..." },
    });
  });

  it("rejects non-essential tools when no server is reachable (#234)", async () => {
    installFetch(() => {
      throw new Error("ECONNREFUSED");
    });
    const localKv = new InMemoryKV(undefined);
    await expect(
      handleToolCall("memory_lesson_save", { title: "x" }, localKv),
    ).rejects.toThrow(/Unknown tool: memory_lesson_save/);
  });

  it("does not retry local after a validation error", async () => {
    const fetchFn = installFetch((url) => {
      if (url.endsWith("/agentmemory/livez")) return new Response("ok", { status: 200 });
      return new Response("{}", { status: 200 });
    });
    const localKv = new InMemoryKV(undefined);
    await expect(
      handleToolCall("memory_save", { content: "" }, localKv),
    ).rejects.toThrow("content is required");
    const remembersCalled = fetchFn.mock.calls.some(([url]) =>
      String(url).endsWith("/agentmemory/remember"),
    );
    expect(remembersCalled).toBe(false);
  });

  it("AGENTMEMORY_FORCE_PROXY=1 skips livez probe and trusts the server", async () => {
    process.env["AGENTMEMORY_FORCE_PROXY"] = "1";
    const calls: string[] = [];
    installFetch((url, init) => {
      calls.push(url);
      if (url.endsWith("/agentmemory/livez")) {
        throw new Error("probe should be skipped");
      }
      if (url.endsWith("/agentmemory/remember")) {
        return new Response(JSON.stringify({ id: "m-1", action: "created" }), {
          status: 200,
          headers: { "content-type": "application/json" },
        });
      }
      return new Response("not found", { status: 404 });
    });
    try {
      await handleToolCall("memory_save", { content: "force-proxy" });
      expect(calls.some((u) => u.endsWith("/agentmemory/livez"))).toBe(false);
      expect(calls.some((u) => u.endsWith("/agentmemory/remember"))).toBe(true);
    } finally {
      delete process.env["AGENTMEMORY_FORCE_PROXY"];
    }
  });

  it("logs probe failure to stderr so sandboxed clients can diagnose silently dropped tools", async () => {
    installFetch((url) => {
      if (url.endsWith("/agentmemory/livez")) {
        throw new Error("ECONNREFUSED 127.0.0.1:3111");
      }
      return new Response("not found", { status: 404 });
    });
    const writes: string[] = [];
    const origWrite = process.stderr.write.bind(process.stderr);
    process.stderr.write = ((chunk: string | Uint8Array) => {
      writes.push(typeof chunk === "string" ? chunk : Buffer.from(chunk).toString("utf8"));
      return true;
    }) as typeof process.stderr.write;
    try {
      const localKv = new InMemoryKV(undefined);
      await handleToolCall("memory_save", { content: "diag" }, localKv);
    } finally {
      process.stderr.write = origWrite;
    }
    const joined = writes.join("");
    expect(joined).toMatch(/livez probe .* failed/);
    expect(joined).toMatch(/AGENTMEMORY_FORCE_PROXY/);
  });

  it("local fallback tools/list returns all 7 IMPLEMENTED_TOOLS regardless of AGENTMEMORY_TOOLS env (#234)", async () => {
    const { handleToolsList } = await import("../src/mcp/standalone.js");
    installFetch(() => {
      throw new Error("ECONNREFUSED");
    });
    delete process.env["AGENTMEMORY_TOOLS"];
    const before = await handleToolsList();
    const beforeTools = before.tools as Array<{ name: string }>;
    expect(beforeTools.map((t) => t.name).sort()).toEqual([
      "memory_audit",
      "memory_export",
      "memory_governance_delete",
      "memory_recall",
      "memory_save",
      "memory_sessions",
      "memory_smart_search",
    ]);
    expect(beforeTools).toHaveLength(7);

    resetHandleForTests();
    process.env["AGENTMEMORY_TOOLS"] = "core";
    const core = await handleToolsList();
    expect((core.tools as unknown[]).length).toBe(7);
    delete process.env["AGENTMEMORY_TOOLS"];
  });

  it("AGENTMEMORY_PROBE_TIMEOUT_MS overrides the default probe timeout", async () => {
    process.env["AGENTMEMORY_PROBE_TIMEOUT_MS"] = "50";
    let probeStarted = 0;
    installFetch((url) => {
      if (url.endsWith("/agentmemory/livez")) {
        probeStarted++;
        return new Response("ok", { status: 200 });
      }
      return new Response("not found", { status: 404 });
    });
    try {
      const localKv = new InMemoryKV(undefined);
      await handleToolCall("memory_save", { content: "timeout-knob" }, localKv);
      expect(probeStarted).toBe(1);
    } finally {
      delete process.env["AGENTMEMORY_PROBE_TIMEOUT_MS"];
    }
  });
});