Add infobox

1 files changed, 51 insertions, 0 deletions

diff --git a/helix-view/src/info.rs b/helix-view/src/info.rs
new file mode 100644
index 00000000..eef8d3a1
--- /dev/null
+++ b/helix-view/src/info.rs
@@ -0,0 +1,51 @@
+use crate::input::KeyEvent;
+use std::fmt::Write;
+use unicode_width::UnicodeWidthStr;
+
+#[derive(Debug)]
+/// Info box used in editor. Rendering logic will be in other crate.
+pub struct Info {
+    /// Title kept as static str for now.
+    pub title: &'static str,
+    /// Text body, should contains newline.
+    pub text: String,
+    /// Body width.
+    pub width: u16,
+    /// Body height.
+    pub height: u16,
+}
+
+impl Info {
+    pub fn key(title: &'static str, body: Vec<(Vec<KeyEvent>, &'static str)>) -> Info {
+        let keymaps_width: u16 = body
+            .iter()
+            .map(|r| r.0.iter().map(|e| e.width() as u16 + 2).sum::<u16>() - 2)
+            .max()
+            .unwrap();
+        let mut text = String::new();
+        let mut width = 0;
+        let height = body.len() as u16;
+        for (mut keyevents, desc) in body {
+            let keyevent = keyevents.remove(0);
+            let mut left = keymaps_width - keyevent.width() as u16;
+            write!(text, "{}", keyevent).ok();
+            for keyevent in keyevents {
+                write!(text, ", {}", keyevent).ok();
+                left -= 2 + keyevent.width() as u16;
+            }
+            for _ in 0..left {
+                text.push(' ');
+            }
+            if keymaps_width + 2 + (desc.width() as u16) > width {
+                width = keymaps_width + 2 + desc.width() as u16;
+            }
+            writeln!(text, "  {}", &desc).ok();
+        }
+        Info {
+            title,
+            text,
+            width,
+            height,
+        }
+    }
+}