From d236c791a10940c10b721ea578e57fc613da088a Mon Sep 17 00:00:00 2001
From: shy <shy@posteo.de>
Date: Fri, 16 Apr 2021 16:01:43 +0200
Subject: [PATCH] Limit input buffer length.

---
 src/alarm.rs  |  6 +++---
 src/buffer.rs | 27 ++++++++++++++++++---------
 src/utils.rs  |  4 ++--
 3 files changed, 23 insertions(+), 14 deletions(-)

diff --git a/src/alarm.rs b/src/alarm.rs
index 363ddc4..f592a36 100644
--- a/src/alarm.rs
+++ b/src/alarm.rs
@@ -109,7 +109,7 @@ impl AlarmRoster {
         if let Some(i) = input.find(DELIMITER) {
             label = input[(i + 1)..].to_string();
             // Truncate label.
-            unicode_truncate(&mut label, LABEL_SIZE_LIMIT);
+            grapheme_truncate(&mut label, LABEL_SIZE_LIMIT, '…');
             time_str = &input[..i].trim();
         } else {
             label = input.clone();
@@ -210,7 +210,7 @@ impl AlarmRoster {
                 let mut col =
                     layout.roster.col
                     + 3
-                    + UnicodeWidthStr::width(&alarm.label[..]) as u16;
+                    + UnicodeWidthStr::width(alarm.label.as_str()) as u16;
                 let mut line = layout.roster.line + index as u16;
 
                 // Compensate for "hidden" items in the alarm roster.
@@ -318,7 +318,7 @@ impl AlarmRoster {
     pub fn width(&self) -> u16 {
         let mut width: u16 = 0;
         for alarm in &self.list {
-            let length = UnicodeWidthStr::width(&alarm.label[..]) as u16;
+            let length = UnicodeWidthStr::width(alarm.label.as_str()) as u16;
             if length > width { width = length };
         }
         // Actual width is 4 columns wider if it's not 0.
diff --git a/src/buffer.rs b/src/buffer.rs
index 0da0ad6..4ab3a03 100644
--- a/src/buffer.rs
+++ b/src/buffer.rs
@@ -4,6 +4,7 @@ use std::io::Write;
 use termion::{clear, cursor, color};
 use termion::raw::RawTerminal;
 use crate::layout::Layout;
+use unicode_width::UnicodeWidthStr;
 use unicode_segmentation::UnicodeSegmentation;
 
 const PROMPT: &str = "Add alarm: ";
@@ -74,7 +75,7 @@ impl Buffer {
 
     // Draw input buffer.
     pub fn draw<W: Write>(
-        &self,
+        &mut self,
         stdout: &mut RawTerminal<W>,
         layout: &mut Layout,
     ) -> Result<(), std::io::Error>
@@ -93,7 +94,22 @@ impl Buffer {
             return Ok(());
         }
 
-        if !self.content.is_empty() {
+        if self.content.is_empty() {
+            // Clear buffer display.
+            write!(stdout,
+                "{}{}{}",
+                cursor::Goto(layout.buffer.col, layout.buffer.line),
+                clear::CurrentLine,
+                cursor::Hide)?;
+        } else {
+            // Check if buffer exceeds limits.
+            while UnicodeWidthStr::width(self.content.as_str())
+                + UnicodeWidthStr::width(PROMPT)
+                > layout.width as usize
+            {
+                self.content.pop();
+            }
+
             write!(stdout,
                 "{}{}{}{}{}",
                 cursor::Goto(layout.buffer.col, layout.buffer.line),
@@ -101,13 +117,6 @@ impl Buffer {
                 PROMPT,
                 cursor::Show,
                 &self.content)?;
-        } else {
-            // Clear buffer display.
-            write!(stdout,
-                "{}{}{}",
-                cursor::Goto(layout.buffer.col, layout.buffer.line),
-                clear::CurrentLine,
-                cursor::Hide)?;
         }
         Ok(())
     }
diff --git a/src/utils.rs b/src/utils.rs
index 66416ed..354f934 100644
--- a/src/utils.rs
+++ b/src/utils.rs
@@ -1,11 +1,11 @@
 extern crate unicode_segmentation;
 use unicode_segmentation::UnicodeSegmentation;
 
-pub fn unicode_truncate(input: &mut String, limit: usize) {
+pub fn grapheme_truncate(input: &mut String, limit: usize, ellipse: char) {
     match UnicodeSegmentation::grapheme_indices(input.as_str(), true).nth(limit) {
         Some((i, _)) => {
             input.truncate(i);
-            input.push('…');
+            input.push(ellipse);
         },
         None => (),
     }