import { join, resolve } from "node:path";
import { DatabaseSync } from "node:sqlite";

import { describe, expect } from "vitest";

import { createTestTempDirectory } from "../../fixtures/temporaryDirectory.js";
import { cliTest } from "../../support/cli/cliFixture.js";
import type { TestProcesses } from "../../support/process/processFixture.js";

/** Run the CLI, closing its stdout reader after `bytes` (0: before any write). */
const runWithClosedReader = async (
  processes: TestProcesses,
  arguments_: readonly string[],
  bytes: number,
) => {
  const child = processes.spawn(
    process.execPath,
    [resolve("scripts/rea.mjs"), ...arguments_],
    { env: { PATH: process.env.PATH ?? "", REA_LOG_LEVEL: "silent" } },
  );
  let received = 0;
  if (bytes === 0) child.stdout.destroy();
  else
    child.stdout.on("data", (chunk: Buffer) => {
      received += chunk.length;
      if (received >= bytes) child.stdout.destroy();
    });
  child.stdin.end();
  let stderr = "";
  child.stderr.setEncoding("utf8");
  child.stderr.on("data", (chunk: string) => (stderr += chunk));
  const code = await new Promise<number | null>((done) =>
    child.once("close", done),
  );
  return { code, stderr, received };
};

// Windows reports a closed pipe reader through a different error path.
describe.skipIf(process.platform === "win32")(
  "CLI with a closed stdout",
  () => {
    cliTest.for([
      ["toon", ["capabilities", "--format", "toon"]],
      ["json", ["capabilities", "--format", "json"]],
      ["mcp doctor", ["mcp", "doctor", "--json"]],
    ] as const)(
      "stops quietly with the SIGPIPE status when the reader closes first ($0)",
      async ([, arguments_], { processes }) => {
        const result = await runWithClosedReader(processes, arguments_, 0);
        expect(result).toMatchObject({ code: 141, stderr: "" });
      },
    );

    cliTest(
      "stops quietly when the reader closes during streamed JSON",
      async ({ processes }) => {
        const directory = await createTestTempDirectory("rea-closed-stdout-");
        const database = join(directory, "rows.db");
        const writer = new DatabaseSync(database);
        writer.exec("CREATE TABLE t (v TEXT)");
        const insert = writer.prepare("INSERT INTO t VALUES (?)");
        // 4 MiB of rows outlasts any pipe buffer, so writes continue after close.
        for (let row = 0; row < 64; row += 1) insert.run("x".repeat(65_536));
        writer.close();
        const result = await runWithClosedReader(
          processes,
          [
            "inspect-sqlite-database",
            database,
            "--table",
            "t",
            "--row-limit",
            "64",
            "--format",
            "json",
          ],
          1,
        );
        expect(result.received).toBeGreaterThan(0);
        expect(result).toMatchObject({ code: 141, stderr: "" });
      },
    );
  },
);