use chrono::{DateTime, FixedOffset};
use markdown::{Block, Span};
use std::convert::identity;

#[derive(Debug)]
pub struct Doc<'src> {
    pub entries: Vec<Entry<'src>>,
}

impl<'src> Doc<'src> {
    // TODO: better parsing errors?
    pub fn new(f: &'src str) -> Option<Self> {
        let entries = f
            .split("\n## ")
            .map(|s| s.split_once("\n"))
            .skip(1)
            .filter_map(identity)
            .map(|(title, content)| (title.split_once(": "), content))
            .map(|(title, content)| {
                if let Some((ts, title)) = title {
                    Some(Entry {
                        timestamp: DateTime::parse_from_rfc3339(ts).unwrap(),
                        title,
                        content: content.trim_matches('\n'),
                    })
                } else {
                    None
                }
            })
            .collect::<Vec<_>>();

        entries.iter().all(|it| it.is_some()).then_some(Self {
            entries: entries.into_iter().filter_map(identity).collect(),
        })
    }
}

#[derive(Debug, Clone)]
pub struct Entry<'src> {
    pub timestamp: DateTime<FixedOffset>,
    pub title: &'src str,
    pub content: &'src str,
}