cmtrace-open 1.5.0

use serde::Serialize;
use std::sync::OnceLock;

#[derive(Debug, Clone, Serialize)]
#[serde(rename_all = "camelCase")]
pub struct SystemFontList {
    pub families: Vec<String>,
}

fn cached_fonts() -> &'static SystemFontList {
    static CELL: OnceLock<SystemFontList> = OnceLock::new();
    CELL.get_or_init(|| {
        let source = font_kit::source::SystemSource::new();
        let mut families = source.all_families().unwrap_or_default();
        families.sort_unstable_by_key(|a| a.to_ascii_lowercase());
        families.dedup();
        families
            .retain(|name| !name.starts_with('.') && !name.starts_with('#') && !name.is_empty());
        SystemFontList { families }
    })
}

#[tauri::command]
pub fn list_system_fonts() -> SystemFontList {
    cached_fonts().clone()
}

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

    #[test]
    fn test_list_returns_non_empty() {
        let result = list_system_fonts();
        assert!(!result.families.is_empty());
    }

    #[test]
    fn test_list_is_sorted() {
        let result = list_system_fonts();
        let mut sorted = result.families.clone();
        sorted.sort_unstable_by_key(|a| a.to_ascii_lowercase());
        assert_eq!(result.families, sorted);
    }

    #[test]
    fn test_no_hidden_fonts() {
        let result = list_system_fonts();
        for family in &result.families {
            assert!(!family.starts_with('.'), "hidden font found: {}", family);
            assert!(!family.starts_with('#'), "hidden font found: {}", family);
            assert!(!family.is_empty(), "empty font name found");
        }
    }
}