use crate::common::util::*;

use std::io::{BufReader, Read, Write};
use std::path::{Path, PathBuf};
use std::fs::{self, OpenOptions, File};
use std::time::{Duration, SystemTime};
use tempfile::tempfile;

macro_rules! inf
{
    ($fname:expr) =>
    {{
        &format!("if={}", $fname)
    }};
}

macro_rules! of
{
    ($fname:expr) =>
    {{
        &format!("of={}", $fname)
    }};
}

macro_rules! fixture_path
{
    ($fname:expr) =>
    {{
        PathBuf::from(format!("./tests/fixtures/dd/{}", $fname))
    }};
}

macro_rules! assert_fixture_exists
{
    ($fname:expr) =>
    {{
        let fpath = fixture_path!($fname);
        if !fpath.exists()
        {
            panic!("Fixture missing: {:?}", fpath);
        }
    }};
}

macro_rules! assert_fixture_not_exists
{
    ($fname:expr) =>
    {{
        let fpath = PathBuf::from(format!("./fixtures/dd/{}", $fname));
        if fpath.exists()
        {
            panic!("Fixture present: {:?}", fpath);
        }
    }};
}

macro_rules! build_test_file {
    ($fp:expr, $data:expr) => {{
        OpenOptions::new()
            .write(true)
            .create(true)
            .truncate(true)
            .open($fp)
            .unwrap()
            .write_all($data)
            .unwrap()
    }};
}

macro_rules! cmp_file (
    ($spec:expr, $test:expr) =>
    {
        let specfile_len = $spec.metadata().unwrap().len();
        let testfile_len = $test.metadata().unwrap().len();
        assert_eq!(testfile_len, specfile_len);

        let spec = BufReader::new($spec);
        let test = BufReader::new($test);

        for (b_spec, b_test) in spec.bytes().zip(test.bytes())
        {
            assert_eq!(b_spec.unwrap(),
                       b_test.unwrap());
        }
    };
);

fn build_ascii_block(n: usize) -> Vec<u8>
{
    (0..=127)
        .cycle()
        .take(n)
        .collect()
}

fn build_ebcdic_block(n: usize) -> Vec<u8>
{
    (0..=255)
        .cycle()
        .take(n)
        .collect()
}

// Sanity Tests
#[test]
fn version()
{
    new_ucmd!()
        .args(&["--version"])
        .succeeds();
}

#[test]
fn help()
{
    new_ucmd!()
        .args(&["--help"])
        .succeeds();
}

#[test]
fn test_stdin_stdout()
{
    let input = build_ascii_block(521);
    let output = String::from_utf8(input.clone()).unwrap();
    new_ucmd!()
        .args(&["status=none"])
        .pipe_in(input)
        .run()
        .no_stderr()
        .stdout_only(output);
}

// Top-Level Items
// count=N, skip=N, status=LEVEL, conv=FLAG, *flag=FLAG
#[test]
fn test_stdin_stdout_count()
{
    let input = build_ascii_block(521);
    let mut output = String::from_utf8(input.clone()).unwrap();
    output.truncate(256);
    new_ucmd!()
        .args(&[
            "status=none",
            "count=2",
            "ibs=128",
        ])
        .pipe_in(input)
        .run()
        .no_stderr()
        .stdout_only(output);
}

#[test]
fn test_stdin_stdout_count_bytes()
{
    let input = build_ascii_block(521);
    let mut output = String::from_utf8(input.clone()).unwrap();
    output.truncate(256);
    new_ucmd!()
        .args(&[
            "status=none",
            "count=256",
            "iflag=count_bytes",
        ])
        .pipe_in(input)
        .run()
        .no_stderr()
        .stdout_only(output);
}

#[test]
fn test_stdin_stdout_skip()
{
    let input = build_ascii_block(521);
    let mut output = String::from_utf8(input.clone()).unwrap();
    let _ = output.drain(..256);
    new_ucmd!()
        .args(&[
            "status=none",
            "skip=2",
            "ibs=128",
        ])
        .pipe_in(input)
        .run()
        .no_stderr()
        .stdout_only(output);
}

#[test]
fn test_stdin_stdout_skip_bytes()
{
    let input = build_ascii_block(521);
    let mut output = String::from_utf8(input.clone()).unwrap();
    let _ = output.drain(..256);
    new_ucmd!()
        .args(&[
            "status=none",
            "skip=256",
            "ibs=128",
            "iflag=skip_bytes",
        ])
        .pipe_in(input)
        .run()
        .no_stderr()
        .stdout_only(output);
}

#[test]
fn test_stdin_stdout_skip_w_multiplier()
{
    let input = build_ascii_block(10*1024);
    let output = String::from_utf8(input[5*1024..].to_vec()).unwrap();
    new_ucmd!()
        .args(&[
            "status=none",
            "skip=5K",
            "iflag=skip_bytes"
        ])
        .pipe_in(input)
        .run()
        .no_stderr()
        .stdout_is(output)
        .success();
}

#[test]
fn test_stdin_stdout_count_w_multiplier()
{
    let input = build_ascii_block(5*1024);
    let output = String::from_utf8(input[..2*1024].to_vec()).unwrap();
    new_ucmd!()
        .args(&[
            "status=none",
            "count=2KiB",
            "iflag=count_bytes",
        ])
        .pipe_in(input)
        .run()
        .no_stderr()
        .stdout_is(output)
        .success();
}

#[test]
fn test_final_stats_noxfer()
{
    new_ucmd!()
        .args(&[
            "status=noxfer",
        ])
        .succeeds()
        .stderr_only("");
}

#[test]
fn test_final_stats_unspec()
{
    let output = vec![
        "0+0 records in",
        "0+0 records out",
        "0 bytes (0 B, 0 B) copied, 0.0 s, 0 B/s",
    ];
    let output = output.into_iter()
                       .fold(String::new(), | mut acc, s | {
                           acc.push_str(s);
                           acc.push('\n');
                           acc
                       });
    new_ucmd!()
        .run()
        .stderr_only(&output)
        .success();
}

#[test]
fn test_excl_causes_failure_when_present()
{
    let fname = "this-file-exists-excl.txt";
    assert_fixture_exists!(&fname);

    let (_fix, mut ucmd) = at_and_ucmd!();
    ucmd.args(&[
        "of=this-file-exists-excl.txt",
        "conv=excl",
    ])
        .fails();
}

#[test]
fn test_atime_updated()
{
    let fname = "this-file-exists-no-noatime.txt";
    assert_fixture_exists!(&fname);

    let (fix, mut ucmd) = at_and_ucmd!();
    ucmd.args(&[
        "status=none",
        inf!(fname),
    ]);

    let pre_atime = fix.metadata(&fname).accessed().unwrap();

    ucmd.pipe_in("")
        .run()
        .no_stderr()
        .success();

    let post_atime = fix.metadata(&fname).accessed().unwrap();
    assert!(pre_atime != post_atime);
}

#[test]
fn test_noatime_does_not_update_infile_atime()
{
    let fname = "this-ifile-exists-noatime.txt";
    assert_fixture_exists!(&fname);

    let (fix, mut ucmd) = at_and_ucmd!();
    ucmd.args(&[
        "status=none",
        "iflag=noatime",
        inf!(fname),
    ]);

    let pre_atime = fix.metadata(&fname).accessed().unwrap();

    ucmd.run()
        .no_stderr()
        .success();

    let post_atime = fix.metadata(&fname).accessed().unwrap();
    assert_eq!(pre_atime, post_atime);
}

#[test]
fn test_noatime_does_not_update_ofile_atime()
{
    let fname = "this-ofile-exists-noatime.txt";
    assert_fixture_exists!(&fname);

    let (fix, mut ucmd) = at_and_ucmd!();
    ucmd.args(&[
        "status=none",
        "oflag=noatime",
        of!(fname),
    ]);

    let pre_atime = fix.metadata(&fname).accessed().unwrap();

    ucmd.pipe_in("")
        .run()
        .no_stderr()
        .success();

    let post_atime = fix.metadata(&fname).accessed().unwrap();
    assert_eq!(pre_atime, post_atime);
}

#[test]
fn test_nocreat_causes_failure_when_not_present()
{
    let fname = "this-file-does-not-exist.txt";
    assert_fixture_not_exists!(&fname);

    let (fix, mut ucmd) = at_and_ucmd!();
    ucmd.args(&[
        "conv=nocreat",
        of!(&fname),
    ])
        .run();

    assert!(!fix.file_exists(&fname));

    ucmd.fails();
}

#[test]
fn test_notrunc_does_not_truncate()
{
    // Set up test if needed (eg. after failure)
    let fname = "this-file-exists-notrunc.txt";
    let fpath = fixture_path!(fname);
    match fpath.metadata()
    {
        Ok(m) if m.len() == 256 => {},
        _ =>
            build_test_file!(&fpath, &build_ascii_block(256)),
    }

    let (fix, mut ucmd) = at_and_ucmd!();
    ucmd.args(&[
        "status=none",
        "conv=notrunc",
        of!(&fname),
        "if=null.txt",
    ])
        .run()
        .no_stdout()
        .no_stderr()
        .success();

    assert_eq!(256, fix.metadata(&fname).len());
}

#[test]
fn test_existing_file_truncated()
{
    // Set up test if needed (eg. after failure)
    let fname = "this-file-exists-truncated.txt";
    let fpath = fixture_path!(fname);
    match fpath.metadata()
    {
        Ok(m) if m.len() == 256 => {},
        _ =>
            build_test_file!(&fpath, &vec![0; 256]),
    }

    let (fix, mut ucmd) = at_and_ucmd!();
    ucmd.args(&[
        "status=none",
        "if=null.txt",
        of!(fname),
    ])
        .run()
        .no_stdout()
        .no_stderr()
        .success();

    assert_eq!(0, fix.metadata(&fname).len());
}

#[test]
fn test_null_stats()
{
    let stats = vec![
        "0+0 records in\n",
        "0+0 records out\n",
        "0 bytes (0 B, 0 B) copied, 0.0 s, 0 B/s\n",
    ];
    let stats = stats.into_iter()
                       .fold(String::new(), | mut acc, s | {
                           acc.push_str(s);
                           acc
                       });

    new_ucmd!()
        .args(&[
            "if=null.txt",
        ])
        .run()
        .stderr_only(stats)
        .success();
}

#[test]
fn test_null_fullblock()
{
    new_ucmd!()
        .args(&[
            "if=null.txt",
            "status=none",
            "iflag=fullblock",
        ])
        .run()
        .no_stdout()
        .no_stderr()
        .success();
}

#[cfg(unix)]
// #[ignore] // See note below before running this test!
#[test]
fn test_fullblock()
{
    let tname = "fullblock-from-urand";
    let tmp_fn = format!("TESTFILE-{}.tmp", &tname);
    let stats = vec![
        "1+0 records in\n",
        "1+0 records out\n",
        "134217728 bytes (134 MB, 128 MiB) copied,",
    ];
    let stats = stats.into_iter()
                       .fold(String::new(), | mut acc, s | {
                           acc.push_str(s);
                           acc
                       });

    let res = new_ucmd!()
        .args(&[
            "if=/dev/urandom",
            of!(&tmp_fn),
            "bs=128M",
            // Note: In order for this test to actually test iflag=fullblock, the bs=VALUE
            // must be big enough to 'overwhelm' urandom's store of bytes.
            // Try executing 'dd if=/dev/urandom bs=128M count=1' (i.e without iflag=fullblock).
            // The stats should contain the line: '0+1 records in' indicating a partial read.
            // Since my system only copies 32 MiB without fullblock, I expect 128 MiB to be
            // a reasonable value for testing most systems.
            "count=1",
            "iflag=fullblock",
        ])
        .run();

    res.success();
    let res_stats = &res.stderr[..stats.len()];
    assert_eq!(&stats, res_stats);
}

// Fileio
#[test]
fn test_ys_to_stdout()
{
    let output: Vec<_> = String::from("y\n")
        .bytes()
        .cycle()
        .take(1024)
        .collect();
    let output = String::from_utf8(output).unwrap();

    new_ucmd!()
        .args(&[
            "status=none",
            "if=y-nl-1k.txt",
        ])
        .run()
        .no_stderr()
        .stdout_is(output)
        .success();
}

#[test]
fn test_zeros_to_stdout()
{
    let output = vec![0; 256*1024];
    let output = String::from_utf8(output).unwrap();
    new_ucmd!()
        .args(&[
            "status=none",
            "if=zero-256k.txt",
        ])
        .run()
        .no_stderr()
        .stdout_is(output)
        .success();
}

#[test]
fn test_to_stdout_with_ibs_obs()
{
    let output: Vec<_> = String::from("y\n")
        .bytes()
        .cycle()
        .take(1024)
        .collect();
    let output = String::from_utf8(output).unwrap();

    new_ucmd!()
        .args(&[
            "status=none",
            "if=y-nl-1k.txt",
            "ibs=521",
            "obs=1031",
        ])
        .run()
        .no_stderr()
        .stdout_is(output)
        .success();
}

#[test]
fn test_ascii_10k_to_stdout()
{
    let output = build_ascii_block(1024*1024);
    // build_test_file!("ascii-10k.txt", &output);
    let output = String::from_utf8(output).unwrap();

    new_ucmd!()
        .args(&[
            "status=none",
            "if=ascii-10k.txt",
        ])
        .run()
        .no_stderr()
        .stdout_is(output)
        .success();
}

#[test]
fn test_zeros_to_file()
{
    let tname = "zero-256k";
    let test_fn = format!("{}.txt", tname);
    let tmp_fn = format!("TESTFILE-{}.tmp", &tname);

    let (fix, mut ucmd) = at_and_ucmd!();
    ucmd.args(&[
        "status=none",
        inf!(test_fn),
        of!(tmp_fn),
    ])
    .run()
    .no_stderr()
    .no_stdout()
    .success();

    cmp_file!(File::open(fixture_path!(&test_fn)).unwrap(),
              fix.open(&tmp_fn));
}

#[test]
fn test_to_file_with_ibs_obs()
{
    let tname = "zero-256k";
    let test_fn = format!("{}.txt", tname);
    let tmp_fn = format!("TESTFILE-{}.tmp", &tname);

    let (fix, mut ucmd) = at_and_ucmd!();
    ucmd.args(&[
        "status=none",
        inf!(test_fn),
        of!(tmp_fn),
        "ibs=222",
        "obs=111",
    ])
        .run()
        .no_stderr()
        .no_stdout()
        .success();

    cmp_file!(File::open(fixture_path!(&test_fn)).unwrap(),
              fix.open(&tmp_fn));
}

#[test]
fn test_ascii_521k_to_file()
{
    let tname = "ascii-521k";
    let input = build_ascii_block(512*1024);
    let tmp_fn = format!("TESTFILE-{}.tmp", &tname);

    let (fix, mut ucmd) = at_and_ucmd!();
    ucmd.args(&[
        "status=none",
        of!(tmp_fn),
    ])
        .pipe_in(input.clone())
        .run()
        .no_stderr()
        .no_stdout()
        .success();

    assert_eq!(512*1024, fix.metadata(&tmp_fn).len());

    cmp_file!({ let mut input_f = tempfile().unwrap();
                input_f.write(&input).unwrap();
                input_f },
              fix.open(&tmp_fn));
}

#[ignore]
#[cfg(unix)]
#[test]
fn test_ascii_5_gibi_to_file()
{
    let tname = "ascii-5G";
    let tmp_fn = format!("TESTFILE-{}.tmp", &tname);

    let (fix, mut ucmd) = at_and_ucmd!();
    ucmd.args(&[
        "status=none",
        "count=5G",
        "iflag=count_bytes",
        "if=/dev/zero",
        of!(tmp_fn),
    ])
        .run()
        .no_stderr()
        .no_stdout()
        .success();

    assert_eq!(5*1024*1024*1024, fix.metadata(&tmp_fn).len());
}

#[test]
fn test_self_transfer()
{
    let fname = "self-transfer-256k.txt";

    let (fix, mut ucmd) = at_and_ucmd!();
    ucmd.args(&[
        "status=none",
        "conv=notrunc",
        inf!(fname),
        of!(fname),
    ]);

    assert!(fix.file_exists(fname));
    assert_eq!(256*1024, fix.metadata(fname).len());

    ucmd.run()
        .no_stdout()
        .no_stderr()
        .success();

    assert!(fix.file_exists(fname));
    assert_eq!(256*1024, fix.metadata(fname).len());
}

// conv=[ascii,ebcdic,ibm], conv=[ucase,lcase], conv=[block,unblock], conv=sync
// TODO: Move conv tests from unit test module