#![allow(dead_code)]

use csv::Reader;

use std::env;
use std::io::{self, Read, Write};
use std::path::PathBuf;
use std::process::{self, Command};

static STRANGE: &'static str = include_str!("../examples/data/strange.csv");
static USPOP: &'static str = include_str!("../examples/data/uspop.csv");
static USPOP_NULL: &'static str =
    include_str!("../examples/data/uspop-null.csv");
static USPOP_LATIN1: &'static [u8] =
    include_bytes!("../examples/data/uspop-latin1.csv");
static WORLDPOP: &'static str =
    include_str!("../examples/data/bench/worldcitiespop.csv");
static SMALLPOP: &'static str = include_str!("../examples/data/smallpop.csv");
static SMALLPOP_COLON: &'static str =
    include_str!("../examples/data/smallpop-colon.csv");
static SMALLPOP_NO_HEADERS: &'static str =
    include_str!("../examples/data/smallpop-no-headers.csv");

#[test]
fn cookbook_read_basic() {
    let mut cmd = cmd_for_example("cookbook-read-basic");
    let out = cmd_output_with(&mut cmd, SMALLPOP.as_bytes());
    assert_eq!(out.stdout().lines().count(), 10);
}

#[test]
fn cookbook_read_serde() {
    let mut cmd = cmd_for_example("cookbook-read-serde");
    let out = cmd_output_with(&mut cmd, SMALLPOP.as_bytes());
    assert_eq!(out.stdout().lines().count(), 10);
}

#[test]
fn cookbook_read_colon() {
    let mut cmd = cmd_for_example("cookbook-read-colon");
    let out = cmd_output_with(&mut cmd, SMALLPOP_COLON.as_bytes());
    assert_eq!(out.stdout().lines().count(), 10);
}

#[test]
fn cookbook_read_no_headers() {
    let mut cmd = cmd_for_example("cookbook-read-no-headers");
    let out = cmd_output_with(&mut cmd, SMALLPOP_NO_HEADERS.as_bytes());
    assert_eq!(out.stdout().lines().count(), 10);
}

#[test]
fn cookbook_write_basic() {
    let mut cmd = cmd_for_example("cookbook-write-basic");
    let out = cmd_output(&mut cmd);
    assert_eq!(out.stdout().lines().count(), 3);
}

#[test]
fn cookbook_write_serde() {
    let mut cmd = cmd_for_example("cookbook-write-serde");
    let out = cmd_output(&mut cmd);
    assert_eq!(out.stdout().lines().count(), 3);
}

#[test]
fn tutorial_setup_01() {
    let mut cmd = cmd_for_example("tutorial-setup-01");
    let out = cmd_output_with(&mut cmd, USPOP.as_bytes());
    assert_eq!(out.stdout().lines().count(), 100);
}

#[test]
fn tutorial_error_01() {
    let mut cmd = cmd_for_example("tutorial-error-01");
    let out = cmd_output_with(&mut cmd, USPOP.as_bytes());
    assert_eq!(out.stdout().lines().count(), 100);
}

#[test]
fn tutorial_error_01_errored() {
    let data = "\
header1,header2
foo,bar
quux,baz,foobar
";
    let mut cmd = cmd_for_example("tutorial-error-01");
    let out = cmd_output_with(&mut cmd, data.as_bytes());
    assert!(out.stderr().contains("thread 'main' panicked"));
}

#[test]
fn tutorial_error_02() {
    let mut cmd = cmd_for_example("tutorial-error-02");
    let out = cmd_output_with(&mut cmd, USPOP.as_bytes());
    assert_eq!(out.stdout().lines().count(), 100);
}

#[test]
fn tutorial_error_02_errored() {
    let data = "\
header1,header2
foo,bar
quux,baz,foobar
";
    let mut cmd = cmd_for_example("tutorial-error-02");
    let out = cmd_output_with(&mut cmd, data.as_bytes());
    assert!(out.stdout_failed().contains("error reading CSV from <stdin>"));
}

#[test]
fn tutorial_error_03() {
    let mut cmd = cmd_for_example("tutorial-error-03");
    let out = cmd_output_with(&mut cmd, USPOP.as_bytes());
    assert_eq!(out.stdout().lines().count(), 100);
}

#[test]
fn tutorial_error_03_errored() {
    let data = "\
header1,header2
foo,bar
quux,baz,foobar
";
    let mut cmd = cmd_for_example("tutorial-error-03");
    let out = cmd_output_with(&mut cmd, data.as_bytes());
    assert!(out.stdout_failed().contains("CSV error:"));
}

#[test]
fn tutorial_error_04() {
    let mut cmd = cmd_for_example("tutorial-error-04");
    let out = cmd_output_with(&mut cmd, USPOP.as_bytes());
    assert_eq!(out.stdout().lines().count(), 100);
}

#[test]
fn tutorial_error_04_errored() {
    let data = "\
header1,header2
foo,bar
quux,baz,foobar
";
    let mut cmd = cmd_for_example("tutorial-error-04");
    let out = cmd_output_with(&mut cmd, data.as_bytes());
    assert!(out.stdout_failed().contains("CSV error:"));
}

#[test]
fn tutorial_read_01() {
    let mut cmd = cmd_for_example("tutorial-read-01");
    cmd.arg(data_dir().join("uspop.csv"));
    let out = cmd_output(&mut cmd);
    assert_eq!(out.stdout().lines().count(), 100);
}

#[test]
fn tutorial_read_headers_01() {
    let mut cmd = cmd_for_example("tutorial-read-headers-01");
    let out = cmd_output_with(&mut cmd, USPOP.as_bytes());
    assert_eq!(out.stdout().lines().count(), 101);
}

#[test]
fn tutorial_read_headers_02() {
    let mut cmd = cmd_for_example("tutorial-read-headers-02");
    let out = cmd_output_with(&mut cmd, USPOP.as_bytes());
    assert_eq!(out.stdout().lines().count(), 102);
}

#[test]
fn tutorial_read_delimiter_01() {
    let mut cmd = cmd_for_example("tutorial-read-delimiter-01");
    let out = cmd_output_with(&mut cmd, STRANGE.as_bytes());
    assert_eq!(out.stdout().lines().count(), 6);
}

#[test]
fn tutorial_read_serde_01() {
    let mut cmd = cmd_for_example("tutorial-read-serde-01");
    let out = cmd_output_with(&mut cmd, USPOP.as_bytes());
    assert_eq!(out.stdout().lines().count(), 100);
    assert!(out.stdout().lines().all(|x| x.contains("pop:")));
}

#[test]
fn tutorial_read_serde_02() {
    let mut cmd = cmd_for_example("tutorial-read-serde-02");
    let out = cmd_output_with(&mut cmd, USPOP.as_bytes());
    assert_eq!(out.stdout().lines().count(), 100);
    assert!(out.stdout().lines().all(|x| x.starts_with("(")));
}

#[test]
fn tutorial_read_serde_03() {
    let mut cmd = cmd_for_example("tutorial-read-serde-03");
    let out = cmd_output_with(&mut cmd, USPOP.as_bytes());
    assert_eq!(out.stdout().lines().count(), 100);
    assert!(out.stdout().lines().all(|x| x.contains("\"City\":")));
}

#[test]
fn tutorial_read_serde_04() {
    let mut cmd = cmd_for_example("tutorial-read-serde-04");
    let out = cmd_output_with(&mut cmd, USPOP.as_bytes());
    assert_eq!(out.stdout().lines().count(), 100);
    assert!(out.stdout().lines().all(|x| x.starts_with("Record { latitude:")));
}

#[test]
fn tutorial_read_serde_05_invalid() {
    let mut cmd = cmd_for_example("tutorial-read-serde-invalid-01");
    let out = cmd_output_with(&mut cmd, USPOP.as_bytes());
    assert_eq!(out.stdout().lines().count(), 100);
    assert!(out.stdout().lines().all(|x| x.starts_with("Record { latitude:")));
}

#[test]
fn tutorial_read_serde_05_invalid_errored() {
    let mut cmd = cmd_for_example("tutorial-read-serde-invalid-01");
    let out = cmd_output_with(&mut cmd, USPOP_NULL.as_bytes());
    assert!(out.stdout_failed().contains("CSV deserialize error:"));
}

#[test]
fn tutorial_read_serde_invalid_06() {
    let mut cmd = cmd_for_example("tutorial-read-serde-invalid-02");
    let out = cmd_output_with(&mut cmd, USPOP_NULL.as_bytes());
    assert_eq!(out.stdout().lines().count(), 100);
    assert!(out.stdout().lines().all(|x| x.starts_with("Record { latitude:")));
}

#[test]
fn tutorial_write_01() {
    let mut cmd = cmd_for_example("tutorial-write-01");
    let out = cmd_output(&mut cmd);
    assert_eq!(out.stdout().lines().count(), 4);
}

#[test]
fn tutorial_write_delimiter_01() {
    let mut cmd = cmd_for_example("tutorial-write-delimiter-01");
    let out = cmd_output(&mut cmd);
    assert_eq!(out.stdout().lines().count(), 4);
    assert!(out.stdout().lines().all(|x| x.contains('\t')));
}

#[test]
fn tutorial_write_serde_01() {
    let mut cmd = cmd_for_example("tutorial-write-serde-01");
    let out = cmd_output(&mut cmd);
    assert_eq!(out.stdout().lines().count(), 4);
}

#[test]
fn tutorial_write_serde_02() {
    let mut cmd = cmd_for_example("tutorial-write-serde-02");
    let out = cmd_output(&mut cmd);
    assert_eq!(out.stdout().lines().count(), 4);
}

#[test]
fn tutorial_pipeline_search_01() {
    let mut cmd = cmd_for_example("tutorial-pipeline-search-01");
    cmd.arg("MA");
    let out = cmd_output_with(&mut cmd, USPOP.as_bytes());
    assert_eq!(out.stdout().lines().count(), 2);
}

#[test]
fn tutorial_pipeline_search_01_errored() {
    let mut cmd = cmd_for_example("tutorial-pipeline-search-01");
    cmd.arg("MA");
    let out = cmd_output_with(&mut cmd, USPOP_LATIN1);
    assert!(out.stdout_failed().contains("invalid utf-8"));
}

#[test]
fn tutorial_pipeline_search_02() {
    let mut cmd = cmd_for_example("tutorial-pipeline-search-02");
    cmd.arg("MA");
    let out = cmd_output_with(&mut cmd, USPOP_LATIN1);
    assert_eq!(out.stdout().lines().count(), 2);
}

#[test]
fn tutorial_pipeline_pop_01() {
    let mut cmd = cmd_for_example("tutorial-pipeline-pop-01");
    cmd.arg("100000");
    let out = cmd_output_with(&mut cmd, USPOP.as_bytes());
    assert_eq!(out.stdout().lines().count(), 4);
}

#[test]
fn tutorial_perf_alloc_01() {
    let mut cmd = cmd_for_example("tutorial-perf-alloc-01");
    let out = cmd_output_with(&mut cmd, WORLDPOP.as_bytes());
    assert_eq!(out.stdout(), "11\n");
}

#[test]
fn tutorial_perf_alloc_02() {
    let mut cmd = cmd_for_example("tutorial-perf-alloc-02");
    let out = cmd_output_with(&mut cmd, WORLDPOP.as_bytes());
    assert_eq!(out.stdout(), "11\n");
}

#[test]
fn tutorial_perf_alloc_03() {
    let mut cmd = cmd_for_example("tutorial-perf-alloc-03");
    let out = cmd_output_with(&mut cmd, WORLDPOP.as_bytes());
    assert_eq!(out.stdout(), "11\n");
}

#[test]
fn tutorial_perf_serde_01() {
    let mut cmd = cmd_for_example("tutorial-perf-serde-01");
    let out = cmd_output_with(&mut cmd, WORLDPOP.as_bytes());
    assert_eq!(out.stdout(), "11\n");
}

#[test]
fn tutorial_perf_serde_02() {
    let mut cmd = cmd_for_example("tutorial-perf-serde-02");
    let out = cmd_output_with(&mut cmd, WORLDPOP.as_bytes());
    assert_eq!(out.stdout(), "11\n");
}

#[test]
fn tutorial_perf_serde_03() {
    let mut cmd = cmd_for_example("tutorial-perf-serde-03");
    let out = cmd_output_with(&mut cmd, WORLDPOP.as_bytes());
    assert_eq!(out.stdout(), "11\n");
}

#[test]
fn tutorial_perf_core_01() {
    let mut cmd = cmd_for_example("tutorial-perf-core-01");
    let out = cmd_output_with(&mut cmd, WORLDPOP.as_bytes());
    assert_eq!(out.stdout(), "11\n");
}

#[test]
fn no_infinite_loop_on_io_errors() {
    struct FailingRead;
    impl Read for FailingRead {
        fn read(&mut self, _buf: &mut [u8]) -> io::Result<usize> {
            Err(io::Error::new(io::ErrorKind::Other, "Broken reader"))
        }
    }

    let mut record_results = Reader::from_reader(FailingRead).into_records();
    let first_result = record_results.next();
    assert!(
        matches!(&first_result, Some(Err(e)) if matches!(e.kind(), csv::ErrorKind::Io(_)))
    );
    assert!(record_results.next().is_none());
}

// Helper functions follow.

/// Return the target/debug directory path.
fn debug_dir() -> PathBuf {
    env::current_exe()
        .expect("test binary path")
        .parent()
        .expect("test binary directory")
        .parent()
        .expect("example binary directory")
        .to_path_buf()
}

/// Return the directory containing the example test binaries.
fn example_bin_dir() -> PathBuf {
    debug_dir().join("examples")
}

/// Return the repo root directory path.
fn repo_dir() -> PathBuf {
    PathBuf::from(env!("CARGO_MANIFEST_DIR"))
}

/// Return the directory containing the example data.
fn data_dir() -> PathBuf {
    repo_dir().join("examples").join("data")
}

/// Return a command ready to execute the given example test binary.
///
/// The command's current directory is set to the repo root.
fn cmd_for_example(name: &str) -> Command {
    let mut cmd = Command::new(example_bin_dir().join(name));
    cmd.current_dir(repo_dir());
    cmd
}

/// Return the (stdout, stderr) of running the command as a string.
///
/// If the command has a non-zero exit code, then this function panics.
fn cmd_output(cmd: &mut Command) -> Output {
    cmd.stdout(process::Stdio::piped());
    cmd.stderr(process::Stdio::piped());
    let child = cmd.spawn().expect("command spawns successfully");
    Output::new(cmd, child)
}

/// Like cmd_output, but sends the given data as stdin to the given child.
fn cmd_output_with(cmd: &mut Command, data: &[u8]) -> Output {
    cmd.stdin(process::Stdio::piped());
    cmd.stdout(process::Stdio::piped());
    cmd.stderr(process::Stdio::piped());
    let mut child = cmd.spawn().expect("command spawns successfully");
    {
        let stdin = child.stdin.as_mut().expect("failed to get stdin");
        stdin.write_all(data).expect("failed to write to stdin");
    }
    Output::new(cmd, child)
}

struct Output {
    stdout: String,
    stderr: String,
    command: String,
    status: process::ExitStatus,
}

impl Output {
    /// Return the (stdout, stderr) of running the given child as a string.
    ///
    /// If the command has a non-zero exit code, then this function panics.
    fn new(cmd: &mut Command, child: process::Child) -> Output {
        let out = child.wait_with_output().expect("command runs successfully");
        let stdout =
            String::from_utf8(out.stdout).expect("valid utf-8 (stdout)");
        let stderr =
            String::from_utf8(out.stderr).expect("valid utf-8 (stderr)");
        Output {
            stdout: stdout,
            stderr: stderr,
            command: format!("{:?}", cmd),
            status: out.status,
        }
    }

    fn stdout(&self) -> &str {
        if !self.status.success() {
            panic!(
                "\n\n==== {:?} ====\n\
                 command failed but expected success!\
                 \n\ncwd: {}\
                 \n\nstatus: {}\
                 \n\nstdout: {}\
                 \n\nstderr: {}\
                 \n\n=====\n",
                self.command,
                repo_dir().display(),
                self.status,
                self.stdout,
                self.stderr
            );
        }
        &self.stdout
    }

    fn stdout_failed(&self) -> &str {
        if self.status.success() {
            panic!(
                "\n\n==== {:?} ====\n\
                 command succeeded but expected failure!\
                 \n\ncwd: {}\
                 \n\nstatus: {}\
                 \n\nstdout: {}\
                 \n\nstderr: {}\
                 \n\n=====\n",
                self.command,
                repo_dir().display(),
                self.status,
                self.stdout,
                self.stderr
            );
        }
        &self.stdout
    }

    fn stderr(&self) -> &str {
        if self.status.success() {
            panic!(
                "\n\n==== {:?} ====\n\
                 command succeeded but expected failure!\
                 \n\ncwd: {}\
                 \n\nstatus: {}\
                 \n\nstdout: {}\
                 \n\nstderr: {}\
                 \n\n=====\n",
                self.command,
                repo_dir().display(),
                self.status,
                self.stdout,
                self.stderr
            );
        }
        &self.stderr
    }
}

/// Consume the reader given into a string.
fn read_to_string<R: io::Read>(mut rdr: R) -> String {
    let mut s = String::new();
    rdr.read_to_string(&mut s).unwrap();
    s
}