//! `toolkit read_file` and `toolkit write_file`, run as `brokerd` runs them. Do not edit.

mod support;

use std::os::unix::fs::PermissionsExt;

use proto::tools::{ReadFileArgs, WriteFileArgs};
use support::{TempDir, json, toolkit};
use toolkit::files::MAX_READ;

fn read(path: &str) -> support::Ran {
    toolkit(
        &["read_file"],
        &json(&ReadFileArgs {
            path: path.to_string(),
        }),
    )
}

fn write(path: &str, content: &str) -> support::Ran {
    let args = WriteFileArgs {
        path: path.to_string(),
        content: content.to_string(),
    };
    toolkit(&["write_file"], &json(&args))
}

#[test]
fn a_file_is_read_exactly() {
    let dir = TempDir::new("read");
    let text = "line one\nline two, no newline at the end: ✓";
    std::fs::write(dir.at("a.md"), text).unwrap();
    let ran = read(&dir.at("a.md"));
    assert_eq!((ran.code, ran.stdout.as_str()), (0, text));
    assert_eq!(ran.stderr, "");
}

#[test]
fn an_empty_file_is_empty_output() {
    let dir = TempDir::new("read-empty");
    std::fs::write(dir.at("e"), "").unwrap();
    let ran = read(&dir.at("e"));
    assert_eq!((ran.code, ran.stdout.as_str()), (0, ""));
}

#[test]
fn what_cannot_be_read_is_exit_1_with_one_line_for_the_model() {
    let dir = TempDir::new("read-bad");
    std::fs::write(dir.at("bin"), [0xff, 0xfe, 0x00]).unwrap();
    std::fs::write(dir.at("big"), vec![b'a'; MAX_READ + 1]).unwrap();
    std::fs::write(dir.at("exact"), vec![b'a'; MAX_READ]).unwrap();
    let cases = [
        (dir.at("missing"), "no such file"),
        (dir.at(""), "is a directory"),
        (dir.at("bin"), "not UTF-8 text"),
        (dir.at("big"), "larger than 1048576 bytes"),
    ];
    for (path, why) in cases {
        let ran = read(&path);
        assert_eq!(ran.code, 1, "{path}");
        assert_eq!(ran.stdout, format!("read_file: {path}: {why}"));
    }
    let ran = read(&dir.at("exact"));
    assert_eq!(
        (ran.code, ran.stdout.len()),
        (0, MAX_READ),
        "exactly the limit is fine"
    );
}

#[test]
fn an_unreadable_file_names_the_error() {
    if is_root() {
        return; // root reads anything
    }
    let dir = TempDir::new("read-perm");
    std::fs::write(dir.at("secret"), "x").unwrap();
    std::fs::set_permissions(dir.at("secret"), std::fs::Permissions::from_mode(0o000)).unwrap();
    let ran = read(&dir.at("secret"));
    assert_eq!(ran.code, 1);
    assert!(
        ran.stdout
            .starts_with(&format!("read_file: {}: ", dir.at("secret"))),
        "{}",
        ran.stdout
    );
    assert!(ran.stdout.contains("ermission denied"), "{}", ran.stdout);
}

#[test]
fn a_file_is_written_created_or_replaced() {
    let dir = TempDir::new("write");
    let ran = write(&dir.at("new.md"), "hello ✓\n");
    assert_eq!(ran.code, 0);
    assert_eq!(
        ran.stdout,
        format!("wrote 10 bytes to {}", dir.at("new.md"))
    );
    assert_eq!(
        std::fs::read_to_string(dir.at("new.md")).unwrap(),
        "hello ✓\n"
    );
    let ran = write(&dir.at("new.md"), "");
    assert_eq!(ran.stdout, format!("wrote 0 bytes to {}", dir.at("new.md")));
    assert_eq!(std::fs::read_to_string(dir.at("new.md")).unwrap(), "");
}

#[test]
fn what_cannot_be_written_is_exit_1() {
    let dir = TempDir::new("write-bad");
    std::fs::create_dir(dir.at("sub")).unwrap();
    let cases = [
        (dir.at("nope/a.md"), "the directory does not exist"),
        (dir.at("sub"), "is a directory"),
    ];
    for (path, why) in cases {
        let ran = write(&path, "x");
        assert_eq!(ran.code, 1, "{path}");
        assert_eq!(ran.stdout, format!("write_file: {path}: {why}"));
    }
    assert!(!dir.path().join("nope").exists(), "no directory is created");
}

#[test]
fn misuse_is_exit_2_with_nothing_on_standard_output() {
    let long = vec![b' '; toolkit::input::MAX_INPUT + 1];
    let cases: [(&[&str], &[u8], &str); 7] = [
        (
            &["read_file"],
            br#"{"path":"/a","mode":1}"#,
            "the arguments do not parse",
        ),
        (&["read_file"], b"", "the arguments do not parse"),
        (
            &["write_file"],
            br#"{"path":"/a"}"#,
            "the arguments do not parse",
        ),
        (&["read_file"], &[0xff, 0xfe], "not UTF-8"),
        (&["read_file"], &long, "larger than 2097152 bytes"),
        (&["format_disk"], b"{}", "unknown tool"),
        (&[], b"{}", "unknown tool"),
    ];
    for (args, input, why) in cases {
        let ran = toolkit(args, input);
        assert_eq!(ran.code, 2, "{args:?}");
        assert_eq!(
            ran.stdout, "",
            "{args:?}: the model sees nothing of a misuse"
        );
        assert!(ran.stderr.contains(why), "{args:?}: {}", ran.stderr);
    }
}

fn is_root() -> bool {
    std::fs::read_to_string("/proc/self/status")
        .map(|s| s.lines().any(|l| l.starts_with("Uid:\t0\t")))
        .unwrap_or(false)
}