import { assert, beforeEach, describe, it, vi } from "vitest";
import type { ProcessRunOptions, ProcessRunResult } from "./processRunner";

const { runProcessMock } = vi.hoisted(() => ({
  runProcessMock: vi.fn<
    (
      command: string,
      args: readonly string[],
      options?: ProcessRunOptions,
    ) => Promise<ProcessRunResult>
  >(),
}));

vi.mock("./processRunner", () => ({
  runProcess: runProcessMock,
}));

function processResult(
  overrides: Partial<ProcessRunResult> & Pick<ProcessRunResult, "stdout" | "code">,
): ProcessRunResult {
  return {
    stdout: overrides.stdout,
    code: overrides.code,
    stderr: overrides.stderr ?? "",
    signal: overrides.signal ?? null,
    timedOut: overrides.timedOut ?? false,
    stdoutTruncated: overrides.stdoutTruncated ?? false,
    stderrTruncated: overrides.stderrTruncated ?? false,
  };
}

describe("searchWorkspaceEntries git-ignore chunking", () => {
  beforeEach(() => {
    runProcessMock.mockReset();
    vi.resetModules();
  });

  it("chunks git check-ignore stdin to avoid building giant strings", async () => {
    const ignoredPaths = Array.from(
      { length: 5000 },
      (_, index) => `ignored/${index.toString().padStart(5, "0")}/${"x".repeat(80)}.ts`,
    );
    const keptPaths = ["src/keep.ts", "docs/readme.md"];
    const listedPaths = [...ignoredPaths, ...keptPaths];
    let checkIgnoreCalls = 0;

    runProcessMock.mockImplementation(async (_command, args, options) => {
      if (args[0] === "rev-parse") {
        return processResult({ code: 0, stdout: "true\n" });
      }

      if (args[0] === "ls-files") {
        return processResult({ code: 0, stdout: `${listedPaths.join("\0")}\0` });
      }

      if (args[0] === "check-ignore") {
        checkIgnoreCalls += 1;
        const chunkPaths = (options?.stdin ?? "").split("\0").filter((value) => value.length > 0);
        const chunkIgnored = chunkPaths.filter((value) => value.startsWith("ignored/"));
        return processResult({
          code: chunkIgnored.length > 0 ? 0 : 1,
          stdout: chunkIgnored.length > 0 ? `${chunkIgnored.join("\0")}\0` : "",
        });
      }

      throw new Error(`Unexpected command: git ${args.join(" ")}`);
    });

    const { searchWorkspaceEntries } = await import("./workspaceEntries");
    const result = await searchWorkspaceEntries({
      cwd: "/virtual/workspace",
      query: "",
      limit: 100,
    });

    assert.isAbove(checkIgnoreCalls, 1);
    assert.isFalse(result.entries.some((entry) => entry.path.startsWith("ignored/")));
    assert.isTrue(result.entries.some((entry) => entry.path === "src/keep.ts"));
  });
});