Update timer.sh

1 files changed, 62 insertions, 0 deletions

diff --git a/bin/unix/timer.sh b/bin/unix/timer.sh
new file mode 100755
index 0000000..ac9c858
--- /dev/null
+++ b/bin/unix/timer.sh
@@ -0,0 +1,62 @@
+#! /bin/bash
+# Ref: https://superuser.com/questions/611538/611582#611582
+
+SIGNAL=${1:-SIGTERM}
+
+# If SIGNAL is received, switch to next display
+trap 'next_display' $SIGNAL
+#trap 'toggle_timer' SIGTSTP
+# Do not print "^C" when SIGINT caught
+stty -ctlecho
+
+# Hide the cursor
+tput civis
+
+display_list=(STOPWATCH COUNTDOWN PERIOD)
+export DISPLAY=0
+
+next_display() {
+  export DISPLAY=$(( ($DISPLAY + 1) %${#display_list[@]} ))
+}
+
+export stop=
+toggle_timer() {
+  [ "$stop" = true ] && export stop= || export stop=true
+}
+
+# Wait user input
+read -p '? ' input
+
+# Modify input to fit the format that `date` can read
+# s -> sec
+# m -> min
+# h -> hour
+[[ "$input" =~ s && ! "$input" =~ sec  ]] && input="$(sed s/s/sec/  <<<"$input")"
+[[ "$input" =~ m && ! "$input" =~ min  ]] && input="$(sed s/m/min/  <<<"$input")"
+[[ "$input" =~ h && ! "$input" =~ hour ]] && input="$(sed s/h/hour/ <<<"$input")"
+
+start=$(date +%s)               # unix epoch of start
+given=$(date +%s -d "$input")   # unix epoch of end
+period=$(( $given - $start ))   # seconds for timer
+
+time=0
+while [ $time -ne $period ]; do
+    [ "$stop" = true ] && sleep 0.3 && continue
+
+    time="$(( $(date +%s) - $start ))"
+    case ${display_list[$DISPLAY]} in
+      STOPWATCH)
+        printf '%s\r' "$(date -u -d @$time +%H:%M:%S)"
+        ;;
+      COUNTDOWN)
+        printf '%s\r' "$(date -u -d @$((period - $time)) +%H:%M:%S)"
+        ;;
+      PERIOD)
+        printf '%s\r' "$(date -u -d @$period +%H:%M:%S)"
+        ;;
+    esac
+
+    sleep 0.3
+done
+
+printf "\e[1;31m$(date -u -d "@$time" +%H:%M:%S)"