// This file is part of the uutils coreutils package.
//
// For the full copyright and license information, please view the LICENSE
// file that was distributed with this source code.
// spell-checker:ignore (words) defaultcheck nocheck helpb helpz nwordb nwordwordz wordtotal

use uutests::new_ucmd;
use uutests::util::TestScenario;
use uutests::util_name;

#[test]
fn test_invalid_arg() {
    new_ucmd!().arg("--definitely-invalid").fails_with_code(1);
}

#[test]
fn ab_no_args() {
    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;
    at.write("a", "a\nz\n");
    at.write("b", "b\nz\n");

    scene
        .ucmd()
        .args(&["a", "b"])
        .succeeds()
        .stdout_is("a\n\tb\n\t\tz\n");
}

#[test]
fn ab_dash_one() {
    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;
    at.write("a", "a\nz\n");
    at.write("b", "b\nz\n");

    scene
        .ucmd()
        .args(&["a", "b", "-1"])
        .succeeds()
        .stdout_is("b\n\tz\n");
}

#[test]
fn ab_dash_two() {
    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;
    at.write("a", "a\nz\n");
    at.write("b", "b\nz\n");

    scene
        .ucmd()
        .args(&["a", "b", "-2"])
        .succeeds()
        .stdout_is("a\n\tz\n");
}

#[test]
fn ab_dash_three() {
    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;
    at.write("a", "a\nz\n");
    at.write("b", "b\nz\n");

    scene
        .ucmd()
        .args(&["a", "b", "-3"])
        .succeeds()
        .stdout_is("a\n\tb\n");
}

#[test]
fn a_empty() {
    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;
    at.write("a", "a\nz\n");
    at.touch("empty");
    scene
        .ucmd()
        .args(&["a", "empty"])
        .succeeds()
        .stdout_is("a\nz\n");
}

#[test]
fn empty_empty() {
    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;
    at.touch("empty");
    scene
        .ucmd()
        .args(&["empty", "empty"])
        .succeeds()
        .no_output();
}

#[test]
fn total() {
    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;
    at.write("a", "a\nz\n");
    at.write("b", "b\nz\n");
    scene
        .ucmd()
        .args(&["--total", "a", "b"])
        .succeeds()
        .stdout_is("a\n\tb\n\t\tz\n1\t1\t1\ttotal\n");
}

#[test]
fn total_with_suppressed_regular_output() {
    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;
    at.write("a", "a\nz\n");
    at.write("b", "b\nz\n");
    scene
        .ucmd()
        .args(&["--total", "-123", "a", "b"])
        .succeeds()
        .stdout_is("1\t1\t1\ttotal\n");
}

#[test]
fn repeated_flags() {
    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;
    at.write("a", "a\nz\n");
    at.write("b", "b\nz\n");
    scene
        .ucmd()
        .args(&["--total", "-123123", "--total", "a", "b"])
        .succeeds()
        .stdout_is("1\t1\t1\ttotal\n");
}

#[test]
fn total_with_output_delimiter() {
    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;
    at.write("a", "a\nz\n");
    at.write("b", "b\nz\n");
    scene
        .ucmd()
        .args(&["--total", "--output-delimiter=word", "a", "b"])
        .succeeds()
        .stdout_is("a\nwordb\nwordwordz\n1word1word1wordtotal\n");
}

#[test]
fn output_delimiter() {
    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;
    at.write("a", "a\nz\n");
    at.write("b", "b\nz\n");
    scene
        .ucmd()
        .args(&["--output-delimiter=word", "a", "b"])
        .succeeds()
        .stdout_is("a\nwordb\nwordwordz\n");
}

#[test]
fn output_delimiter_hyphen_one() {
    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;
    at.write("a", "a\nz\n");
    at.write("b", "b\nz\n");
    scene
        .ucmd()
        .args(&["--output-delimiter", "-1", "a", "b"])
        .succeeds()
        .stdout_is("a\n-1b\n-1-1z\n");
}

#[test]
fn output_delimiter_hyphen_help() {
    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;
    at.write("a", "a\nz\n");
    at.write("b", "b\nz\n");
    scene
        .ucmd()
        .args(&["--output-delimiter", "--help", "a", "b"])
        .succeeds()
        .stdout_is("a\n--helpb\n--help--helpz\n");
}

#[test]
fn output_delimiter_multiple_identical() {
    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;
    at.write("a", "a\nz\n");
    at.write("b", "b\nz\n");
    scene
        .ucmd()
        .args(&[
            "--output-delimiter=word",
            "--output-delimiter=word",
            "a",
            "b",
        ])
        .succeeds()
        .stdout_is("a\nwordb\nwordwordz\n");
}

#[test]
fn output_delimiter_multiple_different() {
    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;
    at.write("a", "a\nz\n");
    at.write("b", "b\nz\n");
    scene
        .ucmd()
        .args(&[
            "--output-delimiter=word",
            "--output-delimiter=other",
            "a",
            "b",
        ])
        .fails()
        .no_stdout()
        .stderr_contains("multiple")
        .stderr_contains("output")
        .stderr_contains("delimiters");
}

#[test]
#[ignore = "This is too weird; deviate intentionally."]
fn output_delimiter_multiple_different_prevents_help() {
    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;
    at.write("a", "a\nz\n");
    at.write("b", "b\nz\n");
    scene
        .ucmd()
        .args(&[
            "--output-delimiter=word",
            "--output-delimiter=other",
            "--help",
            "a",
            "b",
        ])
        .fails()
        .no_stdout()
        .stderr_contains("multiple")
        .stderr_contains("output")
        .stderr_contains("delimiters");
}

#[test]
fn output_delimiter_nul() {
    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;
    at.write("a", "a\nz\n");
    at.write("b", "b\nz\n");
    scene
        .ucmd()
        .args(&["--output-delimiter=", "a", "b"])
        .succeeds()
        .stdout_is("a\n\0b\n\0\0z\n");
}

#[test]
fn zero_terminated() {
    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;

    at.write("a_nul", "a\0z\0");
    at.write("b_nul", "b\0z\0");
    for param in ["-z", "--zero-terminated"] {
        scene
            .ucmd()
            .args(&[param, "a_nul", "b_nul"])
            .succeeds()
            .stdout_is("a\0\tb\0\t\tz\0");
    }
}

#[test]
fn zero_terminated_provided_multiple_times() {
    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;

    at.write("a_nul", "a\0z\0");
    at.write("b_nul", "b\0z\0");
    for param in ["-z", "--zero-terminated"] {
        scene
            .ucmd()
            .args(&[param, param, param, "a_nul", "b_nul"])
            .succeeds()
            .stdout_is("a\0\tb\0\t\tz\0");
    }
}

#[test]
fn zero_terminated_with_total() {
    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;

    at.write("a_nul", "a\0z\0");
    at.write("b_nul", "b\0z\0");

    for param in ["-z", "--zero-terminated"] {
        scene
            .ucmd()
            .args(&[param, "--total", "a_nul", "b_nul"])
            .succeeds()
            .stdout_is("a\0\tb\0\t\tz\x001\t1\t1\ttotal\0");
    }
}

#[ignore = "not implemented"]
#[test]
fn check_order() {
    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;
    at.write("bad_order_1", "e\nd\nb\na\n");
    at.write("bad_order_2", "e\nc\nb\na\n");
    scene
        .ucmd()
        .args(&["--check-order", "bad_order_1", "bad_order_2"])
        .fails()
        .stdout_is("\t\te")
        .stderr_is("error to be defined");
}

#[ignore = "not implemented"]
#[test]
fn nocheck_order() {
    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;
    at.write("bad_order_1", "e\nd\nb\na\n");
    at.write("bad_order_2", "e\nc\nb\na\n");
    new_ucmd!()
        .args(&["--nocheck-order", "bad_order_1", "bad_order_2"])
        .succeeds()
        .stdout_is("\t\te\n\tc\n\tb\n\ta\nd\nb\na\n");
}

// when neither --check-order nor --no-check-order is provided,
// stderr and the error code behaves like check order, but stdout
// behaves like nocheck_order. However with some quirks detailed below.
#[ignore = "not implemented"]
#[test]
fn defaultcheck_order() {
    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;
    at.write("bad_order_1", "e\nd\nb\na\n");
    new_ucmd!()
        .args(&["a", "bad_order_1"])
        .fails()
        .stderr_only("error to be defined");
}

// * the first: if both files are not in order, the default behavior is the only
// behavior that will provide an error message
// * the second: if two rows are paired but are out of order,
// it won't matter if all rows in the two files are exactly the same.
// This is specified in the documentation
#[test]
fn defaultcheck_order_identical_bad_order_files() {
    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;
    at.write("bad_order_1", "e\nd\nb\na\n");
    scene
        .ucmd()
        .args(&["bad_order_1", "bad_order_1"])
        .succeeds()
        .stdout_is("\t\te\n\t\td\n\t\tb\n\t\ta\n");
    scene
        .ucmd()
        .arg("--check-order")
        .args(&["bad_order_1", "bad_order_1"])
        .fails()
        .stdout_is("\t\te\n")
        .stderr_is("comm: file 1 is not in sorted order\n");
}

// * the third: (it is not know whether this is a bug or not)
// for the first incident, and only the first incident,
// where both lines are different and one or both file lines being
// compared are out of order from the preceding line,
// it is ignored and no errors occur.
// * the fourth: (it is not known whether this is a bug or not)
// there are additional, not-yet-understood circumstances where an out-of-order
// pair is ignored and is not counted against the 1 maximum out-of-order line.
#[test]
fn unintuitive_default_behavior_1() {
    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;
    at.write("defaultcheck_unintuitive_1", "m\nh\nn\no\nc\np\n");
    at.write("defaultcheck_unintuitive_2", "m\nh\nn\no\np\n");
    // Here, GNU does not fail, but uutils does
    scene
        .ucmd()
        .args(&["defaultcheck_unintuitive_1", "defaultcheck_unintuitive_2"])
        .fails()
        .stdout_is("\t\tm\n\t\th\n\t\tn\n\t\to\nc\n\t\tp\n");
}

#[test]
fn no_arguments() {
    new_ucmd!().fails().no_stdout();
}

#[test]
fn one_argument() {
    new_ucmd!().arg("a").fails().no_stdout();
}

#[test]
fn test_no_such_file() {
    new_ucmd!()
        .args(&["bogus_file_1", "bogus_file_2"])
        .fails()
        .stderr_only("comm: bogus_file_1: No such file or directory\n");
}

#[test]
fn test_is_dir() {
    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;

    scene
        .ucmd()
        .args(&[".", "."])
        .fails()
        .stderr_only("comm: .: Is a directory\n");

    at.mkdir("dir");
    scene
        .ucmd()
        .args(&["dir", "."])
        .fails()
        .stderr_only("comm: dir: Is a directory\n");

    at.touch("file");
    scene
        .ucmd()
        .args(&[".", "file"])
        .fails()
        .stderr_only("comm: .: Is a directory\n");

    at.touch("file");
    scene
        .ucmd()
        .args(&["file", "."])
        .fails()
        .stderr_only("comm: .: Is a directory\n");
}

#[test]
fn test_sorted() {
    let expected_stderr =
        "comm: file 2 is not in sorted order\ncomm: input is not in sorted order\n";

    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;
    at.write("comm1", "1\n3");
    at.write("comm2", "3\n2");
    scene
        .ucmd()
        .args(&["comm1", "comm2"])
        .fails_with_code(1)
        .stdout_is("1\n\t\t3\n\t2\n")
        .stderr_is(expected_stderr);
}

#[test]
fn test_sorted_check_order() {
    let expected_stderr = "comm: file 2 is not in sorted order\n";

    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;
    at.write("comm1", "1\n3");
    at.write("comm2", "3\n2");
    scene
        .ucmd()
        .arg("--check-order")
        .args(&["comm1", "comm2"])
        .fails_with_code(1)
        .stdout_is("1\n\t\t3\n")
        .stderr_is(expected_stderr);
}

#[test]
fn test_both_inputs_out_of_order() {
    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;
    at.write("file_a", "3\n1\n0\n");
    at.write("file_b", "3\n2\n0\n");

    scene
        .ucmd()
        .args(&["file_a", "file_b"])
        .fails_with_code(1)
        .stdout_is("\t\t3\n1\n0\n\t2\n\t0\n")
        .stderr_is(
            "comm: file 1 is not in sorted order\n\
             comm: file 2 is not in sorted order\n\
             comm: input is not in sorted order\n",
        );
}

#[test]
fn test_both_inputs_out_of_order_last_pair() {
    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;
    at.write("file_a", "3\n1\n");
    at.write("file_b", "3\n2\n");

    scene
        .ucmd()
        .args(&["file_a", "file_b"])
        .fails_with_code(1)
        .stdout_is("\t\t3\n1\n\t2\n")
        .stderr_is(
            "comm: file 1 is not in sorted order\n\
             comm: file 2 is not in sorted order\n\
             comm: input is not in sorted order\n",
        );
}

#[test]
fn test_first_input_out_of_order_extended() {
    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;
    at.write("file_a", "0\n3\n1\n");
    at.write("file_b", "2\n3\n");

    scene
        .ucmd()
        .args(&["file_a", "file_b"])
        .fails_with_code(1)
        .stdout_is("0\n\t2\n\t\t3\n1\n")
        .stderr_is(
            "comm: file 1 is not in sorted order\n\
             comm: input is not in sorted order\n",
        );
}

#[test]
fn test_out_of_order_input_nocheck() {
    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;

    // Create input files
    at.write("file_a", "1\n3\n");
    at.write("file_b", "3\n2\n");

    scene
        .ucmd()
        .arg("--nocheck-order")
        .args(&["file_a", "file_b"])
        .succeeds()
        .stdout_is("1\n\t\t3\n\t2\n")
        .no_stderr();
}

#[test]
fn test_both_inputs_out_of_order_but_identical() {
    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;

    at.write("file_a", "2\n1\n0\n");
    at.write("file_b", "2\n1\n0\n");

    scene
        .ucmd()
        .args(&["file_a", "file_b"])
        .succeeds()
        .stdout_is("\t\t2\n\t\t1\n\t\t0\n")
        .no_stderr();
}

#[test]
fn test_comm_arg_error() {
    let scene = TestScenario::new(util_name!());

    // Test extra argument error case from GNU test
    scene
        .ucmd()
        .args(&["a", "b", "no-such"])
        .fails()
        .code_is(1)
        .stderr_contains("error: unexpected argument 'no-such' found")
        .stderr_contains("Usage: comm [OPTION]... FILE1 FILE2")
        .stderr_contains("For more information, try '--help'.");
    // Test extra argument error case from GNU test
    scene
        .ucmd()
        .args(&["a"])
        .fails()
        .code_is(1)
        .stderr_is("error: the following required arguments were not provided:\n  <FILE2>\n\nUsage: comm [OPTION]... FILE1 FILE2\n\nFor more information, try '--help'.\n");
}

#[test]
fn comm_emoji_sorted_inputs() {
    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;

    at.write("file1", "💐\n🦀\n");
    at.write("file2", "🦀\n🪽\n");

    scene
        .ucmd()
        .args(&["file1", "file2"])
        .env("LC_ALL", "C.UTF-8")
        .succeeds()
        .stdout_only("💐\n\t\t🦀\n\t🪽\n");
}

#[test]
fn test_comm_eintr_handling() {
    // Test that comm properly handles EINTR (ErrorKind::Interrupted) during file comparison
    // This verifies the signal interruption retry logic in are_files_identical function
    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;

    // Create test files with identical content
    let test_content = "line1\nline2\nline3\n";
    at.write("file1", test_content);
    at.write("file2", test_content);

    // Test that comm can handle interrupted reads during file comparison
    // The EINTR handling should retry and complete successfully
    scene
        .ucmd()
        .args(&["file1", "file2"])
        .succeeds()
        .stdout_contains("line1") // Check that content is present (comm adds tabs for identical lines)
        .stdout_contains("line2")
        .stdout_contains("line3");

    // Create test files with identical content
    let test_content = "line1\nline2\nline3\n";
    at.write("file1", test_content);
    at.write("file2", test_content);

    // Test that comm can handle interrupted reads during file comparison
    // The EINTR handling should retry and complete successfully
    scene
        .ucmd()
        .args(&["file1", "file2"])
        .succeeds()
        .stdout_contains("line1") // Check that content is present (comm adds tabs for identical lines)
        .stdout_contains("line2")
        .stdout_contains("line3");
}

#[test]
fn test_output_lossy_utf8() {
    let scene = TestScenario::new(util_name!());
    let at = &scene.fixtures;

    // Create files with invalid UTF-8
    // A: \xfe\n\xff\n
    // B: \xff\n\xfe\n
    at.write_bytes("a", b"\xfe\n\xff\n");
    at.write_bytes("b", b"\xff\n\xfe\n");

    // GNU comm output (and uutils with fix):
    // \xfe\n (col 1)
    // \t\t\xff\n (col 3)
    // \t\xfe\n (col 2)
    // Hex: fe 0a 09 09 ff 0a 09 fe 0a

    scene
        .ucmd()
        .args(&["a", "b"])
        .fails() // Fails because of unsorted input
        .stdout_is_bytes(b"\xfe\n\t\t\xff\n\t\xfe\n");
}

#[test]
#[cfg(any(target_os = "linux", target_os = "android"))]
fn test_comm_anonymous_pipes() {
    use std::{io::Write, os::fd::AsRawFd, process};
    use uucore::pipes::pipe;

    let scene = TestScenario::new(util_name!());

    // Open two anonymous pipes
    let (comm1_reader, mut comm1_writer) = pipe().unwrap();
    let (comm2_reader, mut comm2_writer) = pipe().unwrap();

    // comm reads the data in chunks
    // make content large enough, so that at least two chunks are read
    // default buffer size is 8192, so with 6 characters (5 digits + \n) per line we need to write at least 1366 lines

    // write 1500 lines into comm1: 00000\n00001\n...01500\n
    let mut content = String::new();
    for i in 0..1500 {
        content.push_str(&format!("{i:05}\n"));
    }
    assert!(comm1_writer.write_all(content.as_bytes()).is_ok());
    drop(comm1_writer);

    // write into comm2: 00000\n00001\n...01500\n99999\n
    content.push_str("99999\n");
    assert!(comm2_writer.write_all(content.as_bytes()).is_ok());
    drop(comm2_writer);

    // run comm, showing unique lines in second input
    let comm1_fd = format!("/proc/{}/fd/{}", process::id(), comm1_reader.as_raw_fd());
    let comm2_fd = format!("/proc/{}/fd/{}", process::id(), comm2_reader.as_raw_fd());
    scene
        .ucmd()
        .args(&["-13", &comm1_fd, &comm2_fd])
        .succeeds()
        .stdout_is("99999\n");
}

#[test]
#[cfg(all(target_os = "linux", not(target_env = "musl")))]
fn test_read_error() {
    new_ucmd!()
        .arg("/proc/self/mem")
        .arg("/dev/null")
        .fails()
        .stderr_contains("comm: /proc/self/mem: Input/output error");

    new_ucmd!()
        .arg("/dev/null")
        .arg("/proc/self/mem")
        .fails()
        .stderr_contains("comm: /proc/self/mem: Input/output error");
}

#[test]
#[cfg(target_os = "linux")]
fn test_comm_write_error_dev_full() {
    use std::fs::OpenOptions;
    let scene = TestScenario::new(util_name!());
    scene.fixtures.write("a", "a\n");
    let dev_full = OpenOptions::new().write(true).open("/dev/full").unwrap();
    scene
        .ucmd()
        .args(&["a", "a"])
        .set_stdout(dev_full)
        .fails()
        .stderr_contains("No space left on device");
}