#!/bin/bash
#
# Author: Georg Voell - georg.voell@standby.cloud
# Version: @(#)confirm 3.2.1 10.10.2024 (c)2024 Standby.cloud
# Licensed under the Universal Permissive License v 1.0 as shown at https://oss.oracle.com/licenses/upl/
#
# This script can be used free of charge. Use it as is or customize as needed. It is not guaranteed to be
# error free and you will not be reimbursed for any damage it may cause.
#
#@  Display first parameter (question) and wait for an answer (yes to confirm).
#@  If answer is yes, returncode is 0 else returncode is > 0.
#@  A default answer can be specified marked within "[]" when return is pressed.
#@
#@Usage: confirm [options] question
#@  Options:
#@    -h, --help          : Displays helptext.
#@    -v, --version       : Displays the version of the script.
#@    -y, --yes <string>  : <string>: Allowed "Yes" answers e.g. "y/[yes]"
#@    -n, --no <string>   : <string>: Allowed "No" answers e.g. "n/no"
#@    -a, --abort <string>: <string>: Allowed "Abortion" answers e.g. "q/quit"
#@  Question:
#@    <string>            : Display <string> and wait for confirmation.
#@
#@Examples:
#@  confirm "Do you want to continue?"
#@    Result: "Do you want to continue? (y/yes n/no) [no]:"
#@  confirm "Install the scripts?" -y "y/[yes]"
#@    Result: "Install the scripts? (y/yes n/no) [yes]:"
#@  confirm "Sind Sie sicher?" --yes "j/[ja]" --no "n/nein"
#@    Result: "Sind Sie sicher? (j/ja n/nein) [ja]:"
#@  confirm "¿Hablas español?" --yes "s/si" --no "n/[no]"
#@    Result: "¿Hablas español? (s/si n/no) [no]:"
#@  confirm "Do you want to continue?" --abort "q/quit"
#@    Result: "Do you want to continue? (y/yes n/no q/quit) [quit]:"
#
# Exit codes:
#  00: Confirmed / Ok
#  01: Unknown or wrong parameter or abort.
#  02: No confirmation.
#  99: User interrupt.
#
# See also:
#  **install-scripts**(1)
#
# Code example:
#
#   confirm "Do you want to continue?"
#   result=$?
#   if [ $result -eq 0 ]; then
#     # Answer was yes
#     echo "We want to continue"
#   else
#     # Answer was no
#     echo "We want to stop"
#   fi
#
# Update history:
#
# V 1.0.0 08.01.2017 New version
# V 1.0.1 10.05.2017 Small changes
# V 1.0.2 24.10.2017 String comparison in "sh/bash" is "=" not "=="
# V 3.0.1 27.04.2020 Ask for more than just yes or no
# V 3.0.2 24.05.2020 Rename script from 'askforinput' to 'confirm'
# V 3.0.3 11.06.2020 Using library
# V 3.1.0 05.06.2023 New copyright
# V 3.2.0 12.08.2024 New minor version
# V 3.2.1 10.10.2024 Small bug: tolower
#

# Find executable bash library and source it
lib=`which lib.bash 2>/dev/null | sed 's|^no 'lib.bash' in .*||'`
if [ "$lib" != "" ]; then
	source "$lib"
else
	progdir=`dirname "$0"`
	if [ -r "${progdir}/lib.bash" ]; then
		source "${progdir}/lib.bash"
	else
		echo "Unexpected error: Unable to locate bash library 'lib.bash'."
		exit 1
	fi
fi

# Preset
yesanswers=""
noanswers=""
abortanswers=""
default=""
question=""

# Check parameters: Loop until all parameters are used up
while [ $# -gt 0 ]; do
	pname=${1}
	case "$pname" in
		-y | --yes)
			shift
			if [ "$1" != "" ]; then
				answers=`echo $1 | tolower`
				grepresult=`echo "$answers" | grep '\['`
				if [ "$grepresult" != "" ]; then
					default=`echo "$answers" | cut -d'[' -f2 | cut -d']' -f1`
					yesanswers=`echo "$answers" | tr -d '[' | tr -d ']'`
				else
					yesanswers="$answers"
				fi
				shift
			else
				errstr="Please specify a string with possible answers (separated with '/') after parameter '$pname'."
			fi
			;;
		-n | --no)
			shift
			if [ "$1" != "" ]; then
				answers=`echo $1 | tolower`
				grepresult=`echo "$answers" | grep '\['`
				if [ "$grepresult" != "" ]; then
					default=`echo "$answers" | cut -d'[' -f2 | cut -d']' -f1`
					noanswers=`echo "$answers" | tr -d '[' | tr -d ']'`
				else
					noanswers="$answers"
				fi
				shift
			else
				errstr="Please specify a string with possible answers (separated with '/') after parameter '$pname'."
			fi
			;;
		-a | --abort)
			shift
			if [ "$1" != "" ]; then
				answers=`echo $1 | tolower`
				grepresult=`echo "$answers" | grep '\['`
				if [ "$grepresult" != "" ]; then
					default=`echo "$answers" | cut -d'[' -f2 | cut -d']' -f1`
					abortanswers=`echo "$answers" | tr -d '[' | tr -d ']'`
				else
					abortanswers="$answers"
				fi
				shift
			else
				errstr="Please specify a string with possible answers (separated with '/') after parameter '$pname'."
			fi
			;;
		-v | --version)
			shift
			showversion=true
			;;
		-h | --help)
			shift
			showhelp=true
			;;
		*)
			shift
			paramck=`echo "$pname" | grep '^-'` # Types don't begin with '-'
			if [ "$paramck" != "" ]; then
				errstr="Unknown option '$pname'."
			else
				if [ "$question" = "" ]; then
					question="$pname"
				else
					errstr="Question was already given: '$question'. Unknown additional parameter: '$pname'."
				fi
			fi
	esac
done

# Display help or error message
DisplayHelp

# Set defaults if not specified
if [ "$yesanswers" = "" ]; then
	yesanswers="y/yes"
fi
if [ "$noanswers" = "" ]; then
	noanswers="n/no"
fi

# Build an array of possible answers
yesarray=(`echo $yesanswers | sed 's|/| |g'`)
noarray=(`echo $noanswers | sed 's|/| |g'`)
if [ "$abortanswers" != "" ]; then
	abortarray=(`echo $abortanswers | sed 's|/| |g'`)
fi

# If default was not specified, set a default
if [ "$default" = "" ]; then
	if [ "$abortanswers" != "" ]; then
		len="${#abortarray[@]}"
		let len--
		default="${abortarray[$len]}"
	else
		len="${#noarray[@]}"
		let len--
		default="${noarray[$len]}"
	fi
fi

# Check if we have at least a parameter with the question specified
if [ "$question" = "" ]; then
	exitcode=1
	errormsg $exitcode "($progstr) Please ask a question: e.g.: '$progstr \"Are you doing ok?\"'."
	exit $exitcode
else
	tset=`filecheck -x tset`
	if [ "$tset" != "" ]; then
		$tset
	fi
	
	inp=""
	while [ "$inp" = "" ]; do
		if [ "$abortanswers" != "" ]; then
			printf "${question} (${yesanswers} ${noanswers} ${abortanswers}) [${default}]: "
		else
			printf "${question} (${yesanswers} ${noanswers}) [${default}]: "
		fi
		
		read inp
		inp=`echo $inp | tolower`
		
		if [ "$inp" = "" ]; then
			inp="$default"
		fi
		
		for i in "${yesarray[@]}"; do
			if [ "$inp" = "$i" ]; then
				exit 0
			fi
		done

		if [ "$abortanswers" != "" ]; then
			for i in "${abortarray[@]}"; do
				if [ "$inp" = "$i" ]; then
					exit 1
				fi
			done
		fi
		
		for i in "${noarray[@]}"; do
			if [ "$inp" = "$i" ]; then
				exit 2
			fi
		done

		inp=""
	done
fi

exit $exitcode