posta: generic IMAP/SMTP mail CLI with JSON outputHEADmain

1 files changed, 98 insertions, 0 deletions

diff --git a/src/output.rs b/src/output.rs
new file mode 100644
index 0000000..9cc21b2
--- /dev/null
+++ b/src/output.rs
@@ -0,0 +1,98 @@
+//! JSON and table rendering.
+
+use anyhow::Result;
+use serde_json::Value;
+
+use crate::message::MsgSummary;
+
+pub fn print_json(v: &Value) -> Result<()> {
+    println!("{}", serde_json::to_string_pretty(v)?);
+    Ok(())
+}
+
+/// Truncates to `max` characters, ellipsizing multi-byte text safely.
+pub fn truncate(s: &str, max: usize) -> String {
+    if s.chars().count() <= max {
+        s.to_string()
+    } else {
+        let cut: String = s.chars().take(max.saturating_sub(1)).collect();
+        format!("{cut}…")
+    }
+}
+
+pub fn message_table(items: &[MsgSummary]) -> String {
+    let mut out = String::new();
+    out.push_str(&format!(
+        "{:>6}  {:2}  {:22}  {:32}  {}\n",
+        "UID", "", "DATE", "FROM", "SUBJECT"
+    ));
+    for m in items {
+        let unread = if m.flags.iter().any(|f| f == "\\Seen") {
+            " "
+        } else {
+            "●"
+        };
+        out.push_str(&format!(
+            "{:>6}  {:2}  {:22}  {:32}  {}\n",
+            m.uid,
+            unread,
+            truncate(m.date.as_deref().unwrap_or("-"), 22),
+            truncate(m.from.as_deref().unwrap_or("-"), 32),
+            truncate(m.subject.as_deref().unwrap_or("-"), 60),
+        ));
+    }
+    out
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn truncate_keeps_short_strings() {
+        assert_eq!(truncate("hola", 10), "hola");
+        assert_eq!(truncate("hola", 4), "hola");
+    }
+
+    #[test]
+    fn truncate_ellipsizes_long_strings() {
+        assert_eq!(truncate("abcdefgh", 5), "abcd…");
+    }
+
+    #[test]
+    fn truncate_is_multibyte_safe() {
+        // Would panic with byte-based slicing.
+        assert_eq!(truncate("ñandú y cóndor", 6), "ñandú…");
+        assert_eq!(truncate("🚀🚀🚀🚀", 3), "🚀🚀…");
+    }
+
+    fn sample(flags: &[&str]) -> MsgSummary {
+        MsgSummary {
+            uid: 7,
+            flags: flags.iter().map(|s| s.to_string()).collect(),
+            size: None,
+            date: Some("Fri, 17 Jul 2026 10:00:00 -0300".into()),
+            from: Some("Alice <alice@example.com>".into()),
+            to: None,
+            subject: Some("Hello".into()),
+        }
+    }
+
+    #[test]
+    fn table_marks_unread_messages() {
+        let unread = message_table(&[sample(&[])]);
+        assert!(unread.contains('●'), "unread marker missing:\n{unread}");
+        let read = message_table(&[sample(&["\\Seen"])]);
+        assert!(
+            !read.contains('●'),
+            "read message should have no marker:\n{read}"
+        );
+    }
+
+    #[test]
+    fn table_contains_uid_and_subject() {
+        let t = message_table(&[sample(&[])]);
+        assert!(t.contains("     7"));
+        assert!(t.contains("Hello"));
+    }
+}