pub const TOKEN_COMMENT: char = '|';
pub const TOKEN_NOTE: char = '-';
pub const TOKEN_TASK_DONE: char = 'x';
pub const TOKEN_TASK_UNDONE: char = 'o';

#[derive(Debug, PartialEq, Copy, Clone, serde::Deserialize, serde::Serialize)]
pub enum Kind {
    /// Comments are mostly guides and useful information for the author of the
    /// journal.
    /// You should use them in such a manner that if you delete them right after
    /// completing the month, you won't lose any information worth keeping.
    ///
    /// for example, this could be a legend. or a calendar view.
    Comment,
    /// An atomic unit that indicates that demands no particular action.
    Note,
    /// An atomic unit that once demanded an action.
    TaskDone,
    /// An atomic unit that demands action.
    TaskUndone,
}
impl Kind {
    pub fn token(self) -> char {
        match self {
            Kind::Comment => TOKEN_COMMENT,
            Kind::Note => TOKEN_NOTE,
            Kind::TaskDone => TOKEN_TASK_DONE,
            Kind::TaskUndone => TOKEN_TASK_UNDONE,
        }
    }
    pub fn prefix(self) -> String {
        format!("{}\t", self.token())
    }
}

#[derive(Debug, PartialEq, Clone, serde::Deserialize, serde::Serialize)]
pub struct Bullet {
    /// Specifies the kind of bullet this is.
    /// This also specifies The token
    pub kind: Kind,
    /// Main content of the bullet.
    pub sentence: String,
    /// Tags
    pub tags: Option<Vec<String>>,
}

impl Bullet {
    pub fn basic_format(&self) -> String {
        let item = format!("{}{}", self.kind.prefix(), &self.sentence);
        let Some(tags) = &self.tags else {
            return item;
        };
        format!(
            "{item}\t{}",
            tags.iter()
                .map(|x| format!("#{x}"))
                .collect::<Vec<_>>()
                .join(" ")
        )
    }
}

#[cfg(test)]
mod tests {
    use rstest::rstest;

    use super::*;

    #[rstest]
    #[case(Bullet{ kind: Kind::TaskUndone, sentence:"Something amazing is happening.".to_string() , tags: Some(vec!["tag1".to_owned(), "tag2".to_owned()]) },"o\tSomething amazing is happening.\t#tag1 #tag2")]
    #[case(Bullet{ kind: Kind::Note, sentence:"Something amazing is happening.".to_string() , tags: None },"-\tSomething amazing is happening.")]
    fn basic_format_test(#[case] input: Bullet, #[case] expect: &str) {
        assert_eq!(input.basic_format(), expect.to_owned())
    }
}