Add option to show command runtime

home/.config/shell/prompt

@@ -1,5 +1,16 @@
 #!/usr/bin/env zsh
 
+# Configuration variables:
+
+# Once we are too deep in the filestructure, we can usually afford to shorten
+# the whole working directory and only print something like ~/.../dir3/dir4/dir5
+# instead of ~/dir1/dir2/dir3/dir4/dir5. If this isn't desired, set this to 0
+USE_SHORTENED_WORKDIR=1
+
+# Show how much time it took to run a command
+SHOW_CMD_TIME=1
+
+
 # hide EOL sign ('%')
 export PROMPT_EOL_MARK=""
 
@@ -24,11 +35,6 @@ else
 fi
 RESET="%f"
 
-# Once we are too deep in the filestructure, we can usually afford to shorten
-# the whole working directory and only print something like ~/.../dir3/dir4/dir5
-# instead of ~/dir1/dir2/dir3/dir4/dir5. If this isn't desired, set this to 0
-USE_SHORTENED_WORKDIR=1
-
 # Signals git status of CWD repository (if any)
 git_prompt() {
     ref=$(command git symbolic-ref HEAD 2> /dev/null) || ref=$(command git rev-parse --short HEAD 2> /dev/null) || return 0
@@ -64,13 +70,58 @@ working_directory() {
 	fi
 }
 
+# Execution time tracking hooks, this is unique to zsh, as it can add
+# preexec and precmd hooks. We can utilize this to keep track of the
+# amount of time it took to run certain command. We store the start time
+# within a variable: PROMPT_EXEC_TIME_START, which we then compare and
+# unset after the command was finished. In here, we simply set the
+# PROMPT_EXEC_TIME_DURATION, which is then used in the actual prompt
+# This will only be enabled if SHOW_CMD_TIME is 1.
+exec_time_preexec_hook() {
+    [[ $SHOW_CMD_TIME == 0 ]] && return
+    PROMPT_EXEC_TIME_START=$(date +%s)
+}
+exec_time_precmd_hook() {
+    [[ $SHOW_CMD_TIME == 0 ]] && return
+    [[ -z $PROMPT_EXEC_TIME_START ]] && return
+    local PROMPT_EXEC_TIME_STOP=$(date +%s)
+    PROMPT_EXEC_TIME_DURATION=$(( $PROMPT_EXEC_TIME_STOP - $PROMPT_EXEC_TIME_START ))
+    unset PROMPT_EXEC_TIME_START
+}
+format_time() {
+    # Do some formatting to get nice time (e.g. 2m 12s)
+    # from seconds only
+    local T=$1
+    local D=$((T/60/60/24))
+    local H=$((T/60/60%24))
+    local M=$((T/60%60))
+    local S=$((T%60))
+    [[ $D > 0 ]] && printf '%dd ' $D
+    [[ $H > 0 ]] && printf '%dh ' $H
+    [[ $M > 0 ]] && printf '%dm ' $M
+    printf '%ds' $S
+}
+display_cmd_time() {
+    [[ $SHOW_CMD_TIME == 0 ]] && return
+    [[ -z $PROMPT_EXEC_TIME_DURATION ]] && return
+    # Don't display the time, if it's 0 seconds
+    [[ $PROMPT_EXEC_TIME_DURATION == 0 ]] && return
+    echo -n " ${LBLUE}took $(format_time $PROMPT_EXEC_TIME_DURATION)"
+}
+
 setopt promptsubst  # enable command substitution in prompt
 
+# Setup ZSH hooks to display the running time of commands
+autoload -Uz add-zsh-hook
+add-zsh-hook preexec exec_time_preexec_hook
+add-zsh-hook precmd exec_time_precmd_hook
+
 # Primary Prompt
 [ "$EUID" -eq 0 ] && PS1="$RED%n$RESET" || PS1="$GREEN%n$RESET" # user
 PS1+="$(foreign_prompt)"
 PS1+="$(working_directory)"
 PS1+="\$(git_prompt)"
+#PS1+="\$(display_cmd_time)"
 PS1+=" $PURPLE%(!.#.$)$RESET " # Final symbol (# or $/»)
 
 # Next line prompt
@@ -78,8 +129,8 @@ PS2="$RED\ $RESET"
 
 # Right side prompt (on error)
 if [ $TERM = "linux" ]; then
-	RPS1="%(?..${RED}%? X$RESET)"
+    RPS1="\$(display_cmd_time)%(?..${RED}%? X$RESET)"
 else
-	RPS1="%(?..${RED}%? ↵$RESET)"
+    RPS1="\$(display_cmd_time)%(?..${RED}%? ↵$RESET)"
 fi