#!/bin/bash

Red="\e[31m"
Green="\e[32m"
Yellow="\e[33m"
Blue="\e[34m"
Magenta="\e[35m"
None="\e[0m"

date=${CONFLN_DATE:-$(date +%Y-%m-%d--%H-%M-%S)}


from="$1"
to="$2"
par="$3"

NoOld()
{
	[[ "$par" == *r* ]]
}
Copy()
{
	[[ "$par" == *c* ]]
}
RemoveExtension()
{
	[[ "$par" == *E* ]]
}

if [[ "$to" == *"/" ]]
then
	to="$to$(basename "$from")"
	if RemoveExtension
	then
		to="${to%.*}"
	fi
fi


typeEq()
{
	( [[ -d "$1" ]] && [[ -d "$1" ]] ) || ( [[ -f "$1" ]] && [[ -f "$2" ]] )
}
err()
{
	echo -e "$Red Error: $@ $None" 2>&1
	exit 100
}

if [[ "$from" == "" ]] || [[ "$to" == "" ]]
then
	echo $0 - Config linker 1>&2
	echo Usage: 1>&2
	echo "	$0 from to [parameters]" 1>&2
	echo "	to:" 1>&2
	echo "		filename" 1>&2
	echo "		directory when parameter terminate with '/'" 1>&2
	echo "	parameters:" 1>&2
	echo "		-r Remove old file" 1>&2
	echo "		-c copy file (no soft link)" 1>&2
	echo "		-E remove extension" 1>&2
	exit 1
fi

if [[ ! -e "$from" ]]
then
	echo "File $from not exist." 1>&2
	exit 2
fi

echo -n "confln"
Copy && echo -n -e "${Red}[COPY]$None"
echo -n ": $from -> $to:"

if [[ -e "$to" ]]
then
	if ! Copy && [[ "$(readlink -f $from)" == "$(readlink -f $to)" ]]
	then
		echo -e "$Blue Yet done$None"
		exit 0
	fi
	if Copy && ! [[ "$(readlink -f $from)" == "$(readlink -f $to)" ]] && diff "$to" "$from"  -r >/dev/null &&  typeEq "$from" "$to"
	then
		echo -e "$Blue Yet done$None"
		exit 0
	fi
	in=""
	while [[ "$in" != y ]] && [[ "$in" != n ]]
	do
		echo -n -e "$Yellow File exist! Overwrite?(y/n/d)$None"
		NoOld && echo -n -e "$Red (Delete old)$None"

		read in
		[[ "$in" == "n" ]] && exit 0
		if [[ "$in" == "d" ]]
		then
			typeEq || echo -e "$Red Types are not equivalent.$None"
			diff "$to" "$from" --color=always -r
		fi
	done
	if NoOld
	then
		rm "$to" || err rm
		echo -n "Old file deleted"
	else
		old="$to.old.$date"
		echo -n " Old file is: $old"
		mv -n "$to" "$old" || err mv old file 
	fi
fi

if [[ ! -d "$(dirname "$to" )" ]]
then
	in=""
	while [[ "$in" != y ]] && [[ "$in" != n ]]
	do
		echo -n -e "$Magenta Directory not exist! Create?(y/n)$None"
		read in
		[[ "$in" == "n" ]] && exit 0
	done
	mkdir -p "$(dirname "$to")" || err mkdir
fi

if Copy
then
	cp "$from" "$to" -r || err cp
else
	ln -sr "$from" "$to" || err ln
fi

echo -e "$Green OK$None"