Add command duration plugin

plugins/available/cmd-duration.plugin.bash

@@ -0,0 +1,46 @@
+cite about-plugin
+about-plugin 'keep track of the moment when the last command started, to be able to compute its duration'
+
+# Define tmp dir and file
+COMMAND_DURATION_TMPDIR="${TMPDIR:-/tmp}"
+COMMAND_DURATION_FILE="$COMMAND_DURATION_TMPDIR/bashit_theme_execution_$BASHPID"
+
+COMMAND_DURATION_ICON='  '
+
+trap _command_duration_delete_temp_file EXIT HUP INT TERM
+
+_command_duration_delete_temp_file() {
+    if [[ -f "$COMMAND_DURATION_FILE" ]]; then
+        rm -f "$COMMAND_DURATION_FILE"
+    fi
+}
+
+_command_duration_pre_exec() {
+    date +%s > "$COMMAND_DURATION_FILE"
+}
+
+function _command_duration {
+    local command_duration command_start current_time
+    current_time=$(date +%s)
+
+    if [[ -f "$COMMAND_DURATION_FILE" ]]; then
+        command_start=$(< "$COMMAND_DURATION_FILE")
+        command_duration=$(( current_time - command_start ))
+        command rm "$COMMAND_DURATION_FILE"
+    else
+        command_duration=0
+    fi
+
+    if [[ "$command_duration" -gt 0 ]]; then
+        timer_m=$(( command_duration / 60 ))
+        timer_s=$(( command_duration % 60 ))
+    fi
+
+    if [[ "$timer_m" -gt 0 ]]; then
+        echo "${COMMAND_DURATION_COLOR}$COMMAND_DURATION_ICON$normal${timer_m}m ${timer_s}s"
+    elif [[ "$timer_s" -gt 0 ]]; then
+        echo "${COMMAND_DURATION_COLOR}$COMMAND_DURATION_ICON$normal${timer_s}s"
+    fi
+}
+
+PS0="\[\$(_command_duration_pre_exec)\]"