import { mkdirSync, mkdtempSync, rmSync, writeFileSync } from "node:fs";
import { tmpdir } from "node:os";
import { join } from "node:path";
import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
import { discover, fetchUsage } from "./usage.js";
import type { UsageReport } from "@getpaseo/plugin/server/usage";

function mockFetch(handlers: Map<string, () => Response>): typeof fetch {
  return vi.fn(async (url: RequestInfo | URL) => {
    const key = url.toString();
    const handler = handlers.get(key);
    if (!handler) throw new Error(`Unmocked fetch: ${key}`);
    return handler();
  }) as unknown as typeof fetch;
}

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

describe("zai usage source", () => {
  let homeDir: string;
  let fetchApi: typeof fetch;
  let originalEnv: Record<string, string | undefined>;
  beforeEach(() => {
    homeDir = mkdtempSync(join(tmpdir(), "usage-home-"));
    originalEnv = { ...process.env };
    process.env["HOME"] = homeDir;
    process.env["USERPROFILE"] = homeDir;
    for (const key of [
      "APPDATA",
      "XDG_CONFIG_HOME",
      "COPILOT_TOKEN",
      "GITHUB_TOKEN",
      "GITHUB_PAT",
      "CURSOR_ACCESS_TOKEN",
      "CURSOR_TOKEN",
      "Z_AI_API_KEY",
      "ZAI_API_KEY",
      "GLM_API_KEY",
      "GROK_API_KEY",
      "GROK_TOKEN",
      "KIMI_TOKEN",
      "KIMI_API_KEY",
      "KIMI_CODE_HOME",
      "MINIMAX_API_KEY",
      "MINIMAX_BASE_URL",
    ])
      delete process.env[key];
    fetchApi = mockFetch(new Map());
  });
  afterEach(() => {
    rmSync(homeDir, { recursive: true, force: true });
    for (const key of Object.keys(process.env)) if (!(key in originalEnv)) delete process.env[key];
    for (const key in originalEnv) process.env[key] = originalEnv[key];
  });
  function service(
    _options: {
      platform?: typeof process.platform;
      keychain?: () => Promise<unknown | null>;
      cursorHomeDir?: string;
      kimiHomeDir?: string;
    } = {},
  ) {
    return {
      listUsage: async () => {
        const report = await fetchFirst((url, init) => fetchApi(url, init));
        return {
          providers: [
            {
              providerId: "zai",
              ...report,
              error: report.status === "error" ? report.error : null,
              planLabel: report.status === "available" ? (report.planLabel ?? null) : null,
            },
          ],
        };
      },
    };
  }
  function findProvider(
    result: { providers: Array<{ providerId: string } & UsageReport> },
    id: string,
  ) {
    const report = result.providers.find((item) => item.providerId === id);
    if (!report) throw new Error(`Missing usage source ${id}`);
    return report;
  }
  it("fetches Z.ai usage from ZAI_API_KEY", async () => {
    process.env["ZAI_API_KEY"] = "zai_test_token";
    fetchApi = mockFetch(
      new Map([
        [
          "https://api.z.ai/api/biz/subscription/list",
          () =>
            jsonResponse({
              data: [
                {
                  productName: "GLM Coding Max",
                  status: "VALID",
                  purchaseTime: "2026-01-12 16:55:13",
                  valid: "2026-02-12 16:55:13-2026-03-12 16:55:13",
                },
              ],
            }),
        ],
      ]),
    );

    const zai = findProvider(await service().listUsage(), "zai");

    expect(zai).toMatchObject({
      status: "available",
      planLabel: "GLM Coding Max",
      details: expect.arrayContaining([{ id: "status", label: "Status", value: "VALID" }]),
    });
  });

  it("fetches Z.ai usage from Z_AI_API_KEY, the name the glm-acp-agent CLI uses", async () => {
    process.env["Z_AI_API_KEY"] = "zai_cli_token";
    let authorization: string | null = null;
    fetchApi = (async (_url: RequestInfo | URL, init?: RequestInit) => {
      authorization = (init?.headers as Record<string, string> | undefined)?.Authorization ?? null;
      return jsonResponse({ data: [{ productName: "GLM Coding Max", status: "VALID" }] });
    }) as unknown as typeof fetch;

    const zai = findProvider(await service().listUsage(), "zai");

    expect(authorization).toBe("Bearer zai_cli_token");
    expect(zai).toMatchObject({ status: "available", planLabel: "GLM Coding Max" });
  });

  it("reads Z.ai usage from the credentials file the glm-acp-agent CLI writes", async () => {
    const configDir = join(homeDir, ".config", "glm-acp-agent");
    mkdirSync(configDir, { recursive: true });
    writeFileSync(
      join(configDir, "credentials.json"),
      JSON.stringify({ z_ai_api_key: "zai_file_token" }),
    );
    let authorization: string | null = null;
    fetchApi = (async (_url: RequestInfo | URL, init?: RequestInit) => {
      authorization = (init?.headers as Record<string, string> | undefined)?.Authorization ?? null;
      return jsonResponse({ data: [{ productName: "GLM Coding Max", status: "VALID" }] });
    }) as unknown as typeof fetch;

    const zai = findProvider(await service().listUsage(), "zai");

    expect(authorization).toBe("Bearer zai_file_token");
    expect(zai).toMatchObject({ status: "available" });
  });

  it("honours XDG_CONFIG_HOME for the credentials file", async () => {
    const configDir = join(homeDir, "xdg", "glm-acp-agent");
    mkdirSync(configDir, { recursive: true });
    writeFileSync(
      join(configDir, "credentials.json"),
      JSON.stringify({ z_ai_api_key: "zai_xdg_token" }),
    );
    process.env["XDG_CONFIG_HOME"] = join(homeDir, "xdg");
    let authorization: string | null = null;
    fetchApi = (async (_url: RequestInfo | URL, init?: RequestInit) => {
      authorization = (init?.headers as Record<string, string> | undefined)?.Authorization ?? null;
      return jsonResponse({ data: [{ productName: "GLM Coding Max", status: "VALID" }] });
    }) as unknown as typeof fetch;

    const zai = findProvider(await service().listUsage(), "zai");

    expect(authorization).toBe("Bearer zai_xdg_token");
    expect(zai).toMatchObject({ status: "available" });
  });
});

it("discovery returns a locator when fetch finds zai credentials", async () => {
  const previous = process.env["ZAI_API_KEY"];
  try {
    process.env["ZAI_API_KEY"] = "fixture-token";
    let requested = false;
    await fetchFirst(async () => {
      requested = true;
      return new Response(null, { status: 401 });
    });
    expect(requested).toBe(true);
    expect(await discover()).toEqual([
      { key: "default", input: { store: "env", locator: "ZAI_API_KEY" } },
    ]);
  } finally {
    if (previous === undefined) delete process.env["ZAI_API_KEY"];
    else process.env["ZAI_API_KEY"] = previous;
  }
});

describe("account discovery", () => {
  it.each(["empty home", "unrelated files"])("returns no accounts for %s", async (scenario) => {
    const { mkdtemp, writeFile, rm } = await import("node:fs/promises");
    const directory = await mkdtemp(join(tmpdir(), "usage-empty-"));
    const original = { ...process.env };
    try {
      for (const key of Object.keys(process.env)) delete process.env[key];
      process.env.HOME = directory;
      process.env.USERPROFILE = directory;
      if (scenario === "unrelated files") await writeFile(join(directory, "unrelated.json"), "{}");
      expect(await discover()).toEqual([]);
    } finally {
      for (const key of Object.keys(process.env)) delete process.env[key];
      Object.assign(process.env, original);
      await rm(directory, { recursive: true, force: true });
    }
  });
});

async function fetchFirst(fetchApi: typeof fetch) {
  const accounts = await discover();
  const account = accounts[0];
  if (!account) throw new Error("No configured account");
  return fetchUsage(account.input as Parameters<typeof fetchUsage>[0], fetchApi);
}

it.each([401, 403])("reports an existing login rejected with HTTP %i", async (status) => {
  const previous = process.env["ZAI_API_KEY"];
  try {
    process.env["ZAI_API_KEY"] = "fixture-rejected-login";
    const report = await fetchUsage(
      { store: "env", locator: "ZAI_API_KEY" },
      async () => new Response(null, { status }),
    );
    expect(report).toEqual({ status: "unavailable", problem: { kind: "rejected", status } });
  } finally {
    if (previous === undefined) delete process.env["ZAI_API_KEY"];
    else process.env["ZAI_API_KEY"] = previous;
  }
});