use moments_entities::{Event, Source, TimelineIcon, TimelineItem, TitleSegment};
use serde_json::Value;

const FALLBACK_HOST: &str = "hg-edge.mozilla.org";

pub(crate) fn reshape(event: &Event) -> TimelineItem {
    let p = &event.payload;
    let host = p
        .get("_host")
        .and_then(Value::as_str)
        .unwrap_or(FALLBACK_HOST);
    let repo = p
        .get("_repo")
        .and_then(Value::as_str)
        .unwrap_or("(unknown repo)");
    let node = p.get("node").and_then(Value::as_str).unwrap_or("");
    let short_node: String = node.chars().take(12).collect();
    let desc = p
        .get("desc")
        .and_then(Value::as_str)
        .unwrap_or("")
        .lines()
        .next()
        .unwrap_or("")
        .to_string();
    let author = p
        .get("author")
        .and_then(Value::as_str)
        .map(author_name);

    let mut title = Vec::new();
    if let Some(name) = author {
        title.push(TitleSegment::text(format!("{name} ")));
    }
    title.push(TitleSegment::text("committed "));
    title.push(TitleSegment::link(
        short_node,
        format!("https://{host}/{repo}/rev/{node}"),
    ));
    title.push(TitleSegment::text(" in "));
    title.push(TitleSegment::link(
        repo.to_string(),
        format!("https://{host}/{repo}"),
    ));

    let subtitle = (!desc.is_empty()).then(|| vec![TitleSegment::text(desc)]);

    TimelineItem {
        id: event.id.clone(),
        source: Source::Hg,
        action: event.action.clone(),
        occurred_at: event.occurred_at,
        icon: TimelineIcon::GitCommit,
        title,
        subtitle,
        body: None,
    }
}

/// Drop the `<email>` portion of an hg author string ("Name <email>") and
/// trim — leaves just the display name. If there's no email, return the
/// trimmed input.
fn author_name(s: &str) -> String {
    if let Some(idx) = s.find('<') {
        s[..idx].trim().to_string()
    } else {
        s.trim().to_string()
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use chrono::{TimeZone, Utc};
    use serde_json::json;

    fn ev(payload: Value) -> Event {
        Event {
            id: "hg:build/puppet:abc".into(),
            source: Source::Hg,
            action: "Commit".into(),
            occurred_at: Utc.with_ymd_and_hms(2018, 5, 1, 12, 0, 0).unwrap(),
            public: true,
            payload,
        }
    }

    fn render(item: &TimelineItem) -> String {
        item.title
            .iter()
            .map(|s| match s {
                TitleSegment::Text { text } => text.clone(),
                TitleSegment::Link { text, .. } => text.clone(),
            })
            .collect()
    }

    #[test]
    fn reshape_hg_commit() {
        let raw = json!({
            "_host": "hg-edge.mozilla.org",
            "_repo": "build/puppet",
            "node": "abcdef1234567890abcdef",
            "desc": "Bug 1234 - fix something\n\nlonger body",
            "author": "Rob Thijssen <rthijssen@mozilla.com>"
        });
        let item = reshape(&ev(raw));
        assert_eq!(item.icon, TimelineIcon::GitCommit);
        let r = render(&item);
        assert!(
            r.contains("Rob Thijssen committed abcdef123456 in build/puppet"),
            "got: {r}"
        );
        assert_eq!(
            item.subtitle.unwrap(),
            vec![TitleSegment::text("Bug 1234 - fix something")]
        );
    }

    #[test]
    fn drops_email_from_author() {
        assert_eq!(author_name("Rob Thijssen <rob@example>"), "Rob Thijssen");
        assert_eq!(author_name("nobody"), "nobody");
        assert_eq!(author_name("  spaced  "), "spaced");
    }
}