#! bash

# Useful bash functions. This is sourced by the environment file.
# These are available to scripts, but you shouldn't use them in scripts if you
# want them to be portable.


# Usage: pathremove /path/to/bin [PATH]
# Eg, to remove ~/bin from $PATH
#     pathremove ~/bin PATH
pathremove() {
	local IFS=':'
	local NEWPATH
	local DIR
	local PATHVARIABLE=${2:-PATH}
	for DIR in ${!PATHVARIABLE} ; do
		if [ "${DIR}" != "${1}" ] ; then
			NEWPATH="${NEWPATH:+${NEWPATH}:}${DIR}"
		fi
	done
	export ${PATHVARIABLE}="${NEWPATH}"
}

# Usage: pathprepend /path/to/bin [PATH]
# Eg, to prepend ~/bin to $PATH
#     pathprepend ~/bin PATH
pathprepend() {
	pathremove "${1}" "${2}"
	[ -d "${1}" ] || return
	local PATHVARIABLE="${2:-PATH}"
	export ${PATHVARIABLE}="${1}${!PATHVARIABLE:+:${!PATHVARIABLE}}"
}

# Usage: pathappend /path/to/bin [PATH]
# Eg, to append ~/bin to $PATH
#     pathappend ~/bin PATH
pathappend() {
	pathremove "${1}" "${2}"
	[ -d "${1}" ] || return
	local PATHVARIABLE=${2:-PATH}
	export $PATHVARIABLE="${!PATHVARIABLE:+${!PATHVARIABLE}:}${1}"
}

# Usage: ssource /path/to/shellscript
# Checks if the file exists before sourcing it
ssource() {
	[ -r "${1}" ] && source "${1}"
}

# Sets colours to be appropriate for a light on dark terminal
darkterm() {
	DARK=1
	source "${HOME}/.bash/colors"
}

# Sets the colours to be appropriate for a dark on light terminal
lightterm() {
	DARK=0
	source "${HOME}/.bash/colors"
}

# Usage: mcd somedir
# Creates the directory if it doesn't exist, and changes into it
mcd() {
	mkdir -p "${1}" &&
	cd "${1}"
}


# Load local functions
ssource "${HOME}/.bash/functions_local"