//! Host unit tests for rbsh's parser (rbsh/src/parse.rs is pure: no
//! syscalls). Run with `make unit`; see Cargo.toml next to this file.
extern crate alloc;

#[path = "../src/parse.rs"]
pub mod parse;

#[cfg(test)]
mod tests {
    use crate::parse::*;

    /// The text of every word token, for short assertions.
    fn words(line: &str) -> Vec<String> {
        tokenize(line)
            .unwrap()
            .into_iter()
            .filter_map(|t| match t {
                Token::Word(w) => Some(w.text),
                _ => None,
            })
            .collect()
    }

    /// Parse a line that must hold a pipeline.
    fn pipeline(line: &str) -> Pipeline {
        parse(line).unwrap().unwrap()
    }

    fn texts(c: &Command) -> Vec<&str> {
        c.words.iter().map(|w| w.text.as_str()).collect()
    }

    // --- tokenize ---------------------------------------------------------------

    #[test]
    fn splits_on_whitespace() {
        assert_eq!(words("  ls   -l\tB:/bin  "), ["ls", "-l", "B:/bin"]);
    }

    #[test]
    fn operators_need_no_spaces() {
        let t = tokenize("ls|wc>out<in>>log&").unwrap();
        let kinds: Vec<&str> = t
            .iter()
            .map(|t| match t {
                Token::Word(_) => "w",
                Token::Pipe => "|",
                Token::In => "<",
                Token::Out => ">",
                Token::Append => ">>",
                Token::Background => "&",
            })
            .collect();
        assert_eq!(kinds, ["w", "|", "w", ">", "w", "<", "w", ">>", "w", "&"]);
    }

    #[test]
    fn quotes_group_and_mark_words() {
        let t = tokenize("echo 'a b' \"c|d\" x\"y z\"w").unwrap();
        let w: Vec<(String, bool)> = t
            .into_iter()
            .map(|t| match t {
                Token::Word(w) => (w.text, w.quoted),
                other => panic!("unexpected {:?}", other),
            })
            .collect();
        assert_eq!(
            w,
            [
                ("echo".into(), false),
                ("a b".into(), true),
                ("c|d".into(), true), // | inside quotes is just text
                ("xy zw".into(), true), // one word mixing plain and quoted parts
            ]
        );
    }

    #[test]
    fn empty_quotes_make_an_empty_word() {
        assert_eq!(words("echo ''"), ["echo", ""]);
    }

    #[test]
    fn comments_end_the_line() {
        assert_eq!(words("echo hi # not this"), ["echo", "hi"]);
        assert_eq!(words("# only a comment"), Vec::<String>::new());
        // A # inside a word is text, not a comment.
        assert_eq!(words("echo a#b"), ["echo", "a#b"]);
    }

    #[test]
    fn unterminated_quote_is_an_error() {
        assert!(tokenize("echo 'oops").unwrap_err().contains("unterminated ' quote"));
        assert!(tokenize("echo \"oops").unwrap_err().contains("unterminated \" quote"));
    }

    // --- parse ------------------------------------------------------------------

    #[test]
    fn empty_line_and_comment_are_none() {
        assert_eq!(parse("").unwrap(), None);
        assert_eq!(parse("   ").unwrap(), None);
        assert_eq!(parse("# hi").unwrap(), None);
    }

    #[test]
    fn simple_command() {
        let p = pipeline("ls -l /bin");
        assert_eq!(p.commands.len(), 1);
        assert_eq!(texts(&p.commands[0]), ["ls", "-l", "/bin"]);
        assert!(!p.background);
    }

    #[test]
    fn three_stage_pipeline_with_redirections() {
        let p = pipeline("cat < in.txt | grep x | wc >> count.txt");
        assert_eq!(p.commands.len(), 3);
        assert_eq!(p.commands[0].stdin.as_ref().unwrap().text, "in.txt");
        assert_eq!(texts(&p.commands[1]), ["grep", "x"]);
        let (out, append) = p.commands[2].stdout.as_ref().unwrap();
        assert_eq!((out.text.as_str(), *append), ("count.txt", true));
    }

    #[test]
    fn truncating_redirect_and_last_one_wins() {
        let p = pipeline("echo hi > a > b");
        let (out, append) = p.commands[0].stdout.as_ref().unwrap();
        assert_eq!((out.text.as_str(), *append), ("b", false));
    }

    #[test]
    fn redirection_may_come_first() {
        let p = pipeline("> out.txt echo hi");
        assert_eq!(texts(&p.commands[0]), ["echo", "hi"]);
        assert_eq!(p.commands[0].stdout.as_ref().unwrap().0.text, "out.txt");
    }

    #[test]
    fn background() {
        let p = pipeline("sleep 5 &");
        assert!(p.background);
        assert_eq!(texts(&p.commands[0]), ["sleep", "5"]);
    }

    #[test]
    fn syntax_errors() {
        assert_eq!(parse("| wc").unwrap_err(), "missing command before `|`");
        assert_eq!(parse("ls |").unwrap_err(), "missing command after `|`");
        assert_eq!(parse("ls | | wc").unwrap_err(), "missing command before `|`");
        assert_eq!(parse("> out").unwrap_err(), "missing command");
        assert_eq!(parse("&").unwrap_err(), "missing command");
        assert_eq!(parse("ls >").unwrap_err(), "missing file name after redirection");
        assert_eq!(parse("ls > | wc").unwrap_err(), "missing file name after redirection");
        assert_eq!(parse("sleep 1 & ls").unwrap_err(), "`&` must be at the end of the line");
    }

    // --- drive letters ----------------------------------------------------------

    #[test]
    fn drive_letter_detection() {
        assert_eq!(drive_letter("B:"), Some('B'));
        assert_eq!(drive_letter("c:/x"), Some('C'));
        assert_eq!(drive_letter("C:notes"), Some('C'));
        assert_eq!(drive_letter("B"), None);
        assert_eq!(drive_letter("1:"), None);
        assert_eq!(drive_letter("/mnt"), None);
        assert_eq!(drive_letter(""), None);
    }

    #[test]
    fn unknown_drive_does_not_translate() {
        let d = assign_drives("/ ext2\n/mnt/disk0 fat32\n");
        assert_eq!(translate("Z:/x", &d), None);
        assert_eq!(translate("plain", &d), None);
    }

    #[test]
    fn display_picks_the_longest_match() {
        let d = assign_drives("/ ext2\n/mnt/disk0 fat32\n");
        assert_eq!(display("/mnt/disk0/bin", &d), "B:/bin");
        assert_eq!(display("/mnt/disk01", &d), "A:/mnt/disk01"); // not B:
        assert_eq!(display("/", &d), "A:/");
    }

    #[test]
    fn no_root_line_means_ramfs() {
        let d = assign_drives("/mnt/disk0 fat32\n");
        assert_eq!(d[0].fs, "ramfs");
    }

    fn letters(table: &str) -> Vec<String> {
        assign_drives(table).iter().map(|d| format!("{}:{}", d.letter, d.path)).collect()
    }

    #[test]
    fn contract_v1_drives() {
        // Ramfs root, our FAT32 disk and the kernel's three test disks.
        let t = "/ ramfs\n/tmp ramfs\n/mnt/disk0 fat32\n/mnt/disk1 ext2\n/mnt/disk2 exfat\n/mnt/disk3 btrfs\n";
        assert_eq!(letters(t), ["A:/", "B:/mnt/disk0", "C:/mnt/disk1", "D:/mnt/disk2", "E:/mnt/disk3"]);
    }

    #[test]
    fn contract_v2_drives() {
        // ext2 root, FAT32 data disk, exFAT share (mounted last by the kernel).
        let t = "/ ext2\n/tmp ramfs\n/dev devfs\n/proc procfs\n/mnt/disk0 fat32\n/mnt/share exfat\n";
        assert_eq!(letters(t), ["A:/", "B:/mnt/disk0", "C:/mnt/share"]);
        let d = assign_drives(t);
        assert_eq!(d[0].fs, "ext2");
        assert_eq!(d[2].fs, "exfat");
    }

    #[test]
    fn share_skips_c_for_more_disks() {
        let t = "/ ext2\n/mnt/disk0 fat32\n/mnt/disk1 ext2\n/mnt/disk2 btrfs\n/mnt/share exfat\n";
        assert_eq!(letters(t), ["A:/", "B:/mnt/disk0", "C:/mnt/share", "D:/mnt/disk1", "E:/mnt/disk2"]);
    }

    #[test]
    fn share_without_disks_is_still_c() {
        assert_eq!(letters("/ ext2\n/mnt/share exfat\n"), ["A:/", "C:/mnt/share"]);
    }

    #[test]
    fn translate_and_display_with_share() {
        let d = assign_drives("/ ext2\n/mnt/disk0 fat32\n/mnt/share exfat\n");
        assert_eq!(translate("C:/notes.txt", &d).as_deref(), Some("/mnt/share/notes.txt"));
        assert_eq!(translate("c:", &d).as_deref(), Some("/mnt/share"));
        assert_eq!(translate("B:bin", &d).as_deref(), Some("/mnt/disk0/bin"));
        assert_eq!(translate("A:/etc/motd", &d).as_deref(), Some("/etc/motd"));
        assert_eq!(display("/mnt/share/x", &d), "C:/x");
        assert_eq!(display("/mnt/disk0", &d), "B:/");
        assert_eq!(display("/etc", &d), "A:/etc");
    }
} // mod tests