From d264d8540d7c17068bb4ecb055fe3a37067003e3 Mon Sep 17 00:00:00 2001
From: shy <shy@posteo.de>
Date: Fri, 9 Apr 2021 19:15:31 +0200
Subject: [PATCH] Limit label length.

---
 src/alarm.rs  |  9 ++++++---
 src/common.rs | 11 ++++++++++-
 src/main.rs   |  4 ++--
 3 files changed, 18 insertions(+), 6 deletions(-)

diff --git a/src/alarm.rs b/src/alarm.rs
index 8575b34..4e32821 100644
--- a/src/alarm.rs
+++ b/src/alarm.rs
@@ -3,7 +3,8 @@ use std::process::{Command, Stdio, Child};
 use termion::{color, cursor, style};
 use termion::raw::RawTerminal;
 use crate::{Clock, Layout, Position};
-use crate::common::{COLOR, Config, str_length};
+use crate::common::{COLOR, LABEL_SIZE_LIMIT};
+use crate::common::{Config, unicode_length, unicode_truncate};
 
 
 pub struct Countdown {
@@ -86,6 +87,8 @@ impl AlarmRoster {
 
         if let Some(i) = input.find('/') {
             label = input[(i + 1)..].trim().to_string();
+            // Truncate label.
+            unicode_truncate(&mut label, LABEL_SIZE_LIMIT);
             time_str = &input[..i].trim();
         } else {
             label = input.clone();
@@ -189,7 +192,7 @@ impl AlarmRoster {
                     let mut col =
                         layout.roster.col
                         + 3
-                        + str_length(&alarm.label);
+                        + unicode_length(&alarm.label);
                     let mut line = layout.roster.line + index;
 
                     // Compensate for "hidden" items in the alarm roster.
@@ -266,7 +269,7 @@ impl AlarmRoster {
     pub fn width(&self) -> u16 {
         let mut width: u16 = 0;
         for alarm in &self.list {
-            let length = str_length(&alarm.label);
+            let length = unicode_length(&alarm.label);
             if length > width { width = length };
         }
         // Actual width is 4 columns wider if it's not 0.
diff --git a/src/common.rs b/src/common.rs
index 9ef7777..732bb30 100644
--- a/src/common.rs
+++ b/src/common.rs
@@ -8,11 +8,18 @@ pub struct Config {
     pub command: Option<Vec<String>>,
 }
 
-pub fn str_length(input: &str) -> u16 {
+pub fn unicode_length(input: &str) -> u16 {
     let length = UnicodeSegmentation::graphemes(input, true).count();
     length as u16
 }
 
+pub fn unicode_truncate(input: &mut String, limit: usize) {
+    match UnicodeSegmentation::grapheme_indices(input.as_str(), true).nth(limit) {
+        Some((i, _)) => input.truncate(i),
+        None => (),
+    }
+}
+
 pub const COLOR: [&dyn color::Color; 6] = [
     &color::Cyan,
     &color::Magenta,
@@ -21,6 +28,8 @@ pub const COLOR: [&dyn color::Color; 6] = [
     &color::Blue,
     &color::Red,
 ];
+// Maximum length of labels.
+pub const LABEL_SIZE_LIMIT: usize = 48;
 pub const DIGIT_HEIGHT: u16 = 5;
 pub const DIGIT_WIDTH: u16 = 5;
 pub const DIGITS: [[&str; DIGIT_HEIGHT as usize]; 10] = [
diff --git a/src/main.rs b/src/main.rs
index f9f0053..56ddb68 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -20,7 +20,7 @@ use termion::input::TermRead;
 use clock::Clock;
 use alarm::{Countdown, AlarmRoster, exec_command};
 use layout::{Layout, Position};
-use common::{Config, str_length};
+use common::{Config, unicode_length};
 
 
 const NAME: &str = env!("CARGO_PKG_NAME");
@@ -542,7 +542,7 @@ fn draw_buffer<W: Write>(
             cursor::Show,
             buffer)
             .unwrap();
-        layout.cursor.col = layout.buffer.col + 11 + str_length(buffer);
+        layout.cursor.col = layout.buffer.col + 11 + unicode_length(buffer);
     } else {
         // Clear buffer display.
         write!(stdout,