import { assert, assertEquals, assertRejects, assertStringIncludes } from "@std/assert";
import { BACKGROUND_CONTEXT, withAbortSignal } from "@earendil-works/chord/context";
import { join } from "node:path";
import { tempDir, until } from "@berry/util";
import { localEnvironment } from "./environment.ts";

Deno.test({
  name:
    "pseudo-terminals preserve argv, Unicode, cwd and environment, and support input and resizing",
  ignore: !["linux", "windows"].includes(Deno.build.os),
  async fn() {
    await using root = await tempDir();
    const cwd = join(root.path, "terminal 🐈");
    await Deno.mkdir(cwd);
    const env = localEnvironment(cwd);
    const args = ["", 'a "quote"', "C:\\trailing\\", "héllo 🐈"];
    const script = `
      console.log('args=' + JSON.stringify(Deno.args));
      console.log('cwd=' + Deno.cwd());
      console.log('env=' + Deno.env.get('BERRY_PTY_TEST'));
      console.log('tty=' + Deno.stdin.isTerminal() + ',' + Deno.stdout.isTerminal());
      if (Deno.build.os === 'windows') {
        const kernel = Deno.dlopen('kernel32.dll', {
          SetConsoleCP: { parameters: ['u32'], result: 'i32' },
        });
        // ReadFile uses the application's console code page, not ConPTY's UTF-8 transport
        if (!kernel.symbols.SetConsoleCP(65001)) throw new Error('SetConsoleCP failed');
        kernel.close();
      }
      Deno.stdin.setRaw(true);
      console.log('ready');
      const input = new Uint8Array(1024);
      const decoder = new TextDecoder();
      let typed = '';
      while (!typed.includes('\\r')) {
        const count = await Deno.stdin.read(input);
        if (count === null) break;
        typed += decoder.decode(input.subarray(0, count), { stream: true });
      }
      console.log('input=' + typed.trimEnd());
      console.log('size=' + JSON.stringify(Deno.consoleSize()));
      Deno.exit(7);
    `;
    const pty = await env.pty([Deno.execPath(), "eval", script, ...args], {
      cols: 160,
      rows: 30,
      env: { BERRY_PTY_TEST: "value 🐈" },
    }, BACKGROUND_CONTEXT);
    let output = "";
    const reading = (async () => {
      const decoder = new TextDecoder();
      for await (const chunk of pty.readable) output += decoder.decode(chunk, { stream: true });
      output += decoder.decode();
    })();
    const input = pty.writable.getWriter();
    try {
      await until(() => output.includes("ready"));
      assertStringIncludes(output, "args=" + JSON.stringify(args));
      assertStringIncludes(output, "cwd=" + cwd);
      assertStringIncludes(output, "env=value 🐈");
      assertStringIncludes(output, "tty=true,true");
      pty.resize(140, 40);
      await input.write(new TextEncoder().encode("typed héllo\r"));
      assertEquals(await pty.exited, 7);
      await reading;
      assertStringIncludes(output, "input=typed héllo");
      assertStringIncludes(output, 'size={"columns":140,"rows":40}');
    } finally {
      pty.kill();
      await reading;
      await pty.exited;
      input.releaseLock();
    }
  },
});

Deno.test({
  name: "ConPTY closes on abort and output cancellation, and can start again after a failed spawn",
  ignore: Deno.build.os !== "windows",
  async fn() {
    const env = localEnvironment(Deno.cwd());
    await assertRejects(() =>
      env.pty(["berry-nonexistent-program.exe"], {
        cols: 80,
        rows: 24,
      }, BACKGROUND_CONTEXT)
    );

    const controller = new AbortController();
    const pty = await env.pty([Deno.execPath(), "eval", "setInterval(() => {}, 1000)"], {
      cols: 80,
      rows: 24,
    }, withAbortSignal(controller.signal, BACKGROUND_CONTEXT));
    const drained = pty.readable.pipeTo(new WritableStream());
    controller.abort();
    assertEquals(await pty.exited, null);
    await drained;

    const noisy = await env.pty(
      [
        Deno.execPath(),
        "eval",
        `
      const block = new TextEncoder().encode('x'.repeat(65536));
      while (true) await Deno.stdout.write(block);
    `,
      ],
      { cols: 80, rows: 24 },
      BACKGROUND_CONTEXT,
    );
    const reader = noisy.readable.getReader();
    assert(!(await reader.read()).done);
    await reader.cancel();
    await noisy.exited;
    noisy.kill();
  },
});