#!/bin/bash
# shebang for syntax highlightin purposes

__debug_trap() {
	# Set necessary pre-command variables (PROMPT_COMMAND is a
	# command so its excluded here)
	if [[ "$BASH_COMMAND" != "$PROMPT_COMMAND" &&
	      "$LAST_BASH_COMMAND" == "$PROMPT_COMMAND" ]]; then
		LAST_RT="$EPOCHREALTIME"
		INC_TIME=1
	fi
	LAST_BASH_COMMAND="$BASH_COMMAND"
}

trap '__debug_trap' DEBUG

__get_cmd_time() {
	# Set hours minutes seconds and remove preceding zeros
	TZ=UTC
	local YEAR=$(($((10#$(printf '%(%Y)T' $CMD_TIME)))-1970))
	local DAYS=$((10#$(printf '%(%j)T' $CMD_TIME)))
	local HOUR=$((10#$(printf '%(%H)T' $CMD_TIME)))
	local MINS=$((10#$(printf '%(%M)T' $CMD_TIME)))
	local SECS=$((10#$(printf '%(%S)T' $CMD_TIME))) #wtf sex???

	# Choose whether or not to print hours minutes and seconds
	[ $CMD_TIME -ge 31536000 ] && printf '%sd ' ${YEAR:-0}
	[ $CMD_TIME -ge 86400    ] && printf '%sd ' ${DAYS:-0}
	[ $CMD_TIME -ge 3600     ] && printf '%sh ' ${HOUR:-0}
	[ $CMD_TIME -ge 60       ] && printf '%sm ' ${MINS:-0}
	[ $CMD_TIME -ge 1        ] && printf '%ss ' ${SECS:-0}
	                              printf '%sμs' ${CMD_US:-0}
}

__sig() {
	# Giant switch case for getting the name of the signal (`kill -l`)
	case $1 in
		126) printf ACCES  ;;
		127) printf NOENT  ;;
		129) printf HUP    ;;
		130) printf INT    ;;
		131) printf QUIT   ;;
		132) printf ILL    ;;
		133) printf TRAP   ;;
		134) printf ABRT   ;;
		135) printf BUS    ;;
		136) printf FPE    ;;
		137) printf KILL   ;;
		138) printf USR1   ;;
		139) printf SEGV   ;;
		140) printf USR2   ;;
		141) printf PIPE   ;;
		142) printf ALRM   ;;
		143) printf TERM   ;;
		144) printf STKFLT ;;
		145) printf CHLD   ;;
		146) printf CONT   ;;
		147) printf STOP   ;;
		148) printf TSTP   ;;
		149) printf TTIN   ;;
		150) printf TTOU   ;;
		151) printf URG    ;;
		152) printf XCPU   ;;
		153) printf XFSZ   ;;
		154) printf VTALRM ;;
		155) printf PROF   ;;
		156) printf WINCH  ;;
		157) printf IO     ;;
		158) printf PWR    ;;
		159) printf SYS    ;;
		16[3-9]|1[7-8][0-9]|19[0-2]) printf RT$(($1-128)) ;; # Savagery
		*)   printf $1     ;; # Print exit code if not in list
	esac
}

__prompt() {
	# Get exit code
	local PEC=${?:-0}

	# LAST_RT is not set before a command is run
	LAST_RT="${LAST_RT:-$EPOCHREALTIME}"

	# Reset time when prompt was first displayed after command
	if [ ${INC_TIME:-1} -ne 0 ]; then 
		PROMPT_RT="$EPOCHREALTIME"
		INC_TIME=0
	fi

	# Get relative times

	# Remove decimal point, simulating multiplying by 1 million
	PROMPT_RT1M="${PROMPT_RT%.*}${PROMPT_RT#*.}"
	LAST_RT1M="${LAST_RT%.*}${LAST_RT#*.}"
	# Subtract and divide by 1 million to get a more accurate difference
	CMD_TIME="$(((PROMPT_RT1M-LAST_RT1M)/1000000))"
	CMD_TIME="${CMD_TIME:-0}"

	local LAST_US="$((10#${LAST_RT: -6}))"
	local LAST_US="${LAST_US:-0}"
	local PROMPT_US="${PROMPT_RT: -6}"
	local PROMPT_US_CLN="$((10#$PROMPT_US))"
	local PROMPT_US_CLN="${PROMPT_US_CLN:-0}"

	[ $PROMPT_US_CLN -lt $LAST_US ] &&
		CMD_US="$((1$PROMPT_US-$LAST_US))" ||
		CMD_US="$(($PROMPT_US_CLN-$LAST_US))"
	CMD_US="$((10#$CMD_US))"

	# Set prompt sections

	# Colors
	local NON="\[\033[0m\]"
	local BLD="\[\033[1m\]" # YEP BALD
	local BLK="\[\033[30m\]"
	local RED="\[\033[31m\]"
	local GRN="\[\033[32m\]"
	local YLW="\[\033[33m\]"
	local BLU="\[\033[34m\]"
	local PRP="\[\033[35m\]"
	local CYN="\[\033[36m\]"
	local WHT="\[\033[37m\]"

	# Text

	# [INT], [4], etc.
	local SIG="$([ $PEC -ne 0 ] && printf '%s[%s%s%s] ' "$BLU" "$RED" "$(__sig $PEC)" "$BLU")"

	# [user@homeserver:~]
	local COL="$([ $UID -eq 0 ] && printf %s "$RED" || printf %s "$YLW")"
	local UHD="$BLD$BLU[$COL\u$PRP@$CYN\h$PRP:$GRN\w$BLU]"

	# 2y 351d 12m 43s 382969μs
	local TIME="$YLW$(__get_cmd_time)"

	# Random colored $ or #
	local RAND256="\[\033[38;2;$RANDOM;$RANDOM;${RANDOM}m\]"
	local IND="$RAND256\\$"

	# Set the prompt
	PS1="$NON$SIG$UHD $TIME $IND $NON"
}
	
PROMPT_COMMAND=__prompt