Move table_formatting to prelude (#38)

youmubot-prelude/src/lib.rs

@@ -11,6 +11,7 @@ pub mod member_cache;
 pub mod pagination;
 pub mod ratelimit;
 pub mod setup;
+pub mod table_format;
 
 pub use announcer::{Announcer, AnnouncerHandler};
 pub use args::{ChannelId, Duration, RoleId, UserId, UsernameArg};

youmubot-prelude/src/table_format.rs

@@ -0,0 +1,70 @@
+use serenity::all::MessageBuilder;
+
+#[derive(Debug, Copy, Clone, PartialEq, Eq)]
+pub enum Align {
+    Left,
+    Middle,
+    Right,
+}
+
+impl Align {
+    fn pad(self, input: &str, len: usize) -> String {
+        match self {
+            Align::Left => format!("{:<len$}", input),
+            Align::Middle => format!("{:^len$}", input),
+            Align::Right => format!("{:>len$}", input),
+        }
+    }
+}
+
+pub fn table_formatting<const N: usize, S: AsRef<str> + std::fmt::Debug, Ts: AsRef<[[S; N]]>>(
+    headers: &[&'static str; N],
+    padding: &[Align; N],
+    table: Ts,
+) -> String {
+    let table = table.as_ref();
+    // get length for each column
+    let lens = headers
+        .iter()
+        .enumerate()
+        .map(|(i, header)| {
+            table
+                .iter()
+                .map(|r| r.as_ref()[i].as_ref().len())
+                .max()
+                .unwrap_or(0)
+                .max(header.len())
+        })
+        .collect::<Vec<_>>();
+    // paint with message builder
+    let mut m = MessageBuilder::new();
+    m.push_line("```");
+    // headers first
+    for (i, header) in headers.iter().enumerate() {
+        if i > 0 {
+            m.push(" | ");
+        }
+        m.push(padding[i].pad(header, lens[i]));
+    }
+    m.push_line("");
+    // separator
+    m.push_line(format!(
+        "{:-<total$}",
+        "",
+        total = lens.iter().sum::<usize>() + (lens.len() - 1) * 3
+    ));
+    // table itself
+    for row in table {
+        let row = row.as_ref();
+        for (i, cell) in row.iter().enumerate() {
+            if i > 0 {
+                m.push(" | ");
+            }
+            let cell = cell.as_ref();
+            m.push(padding[i].pad(cell, lens[i]));
+        }
+        m.push_line("");
+    }
+    m.push("```");
+    m.build()
+}