posix-shell: Add utils.sh

This files can be sourced by shell configs and replaces the scripts
repository [1].

[1]: https://xengineering.eu/git/scripts

2 files changed, 219 insertions, 0 deletions

diff --git a/.bashrc b/.bashrc
index 890e5dc..8c87e8f 100644
--- a/.bashrc
+++ b/.bashrc
@@ -6,6 +6,7 @@
 . "${HOME}/.config/posix-shell/constants.sh"
 . "${HOME}/.config/posix-shell/aliases.sh"
 . "${HOME}/.config/posix-shell/programs.sh"
+. "${HOME}/.config/posix-shell/utils.sh"
 
 parse_git_branch() {
      git branch 2> /dev/null | sed -e '/^[^*]/d' -e 's/* \(.*\)/ (\1)/'
diff --git a/posix-shell/utils.sh b/posix-shell/utils.sh
new file mode 100644
index 0000000..596263e
--- /dev/null
+++ b/posix-shell/utils.sh
@@ -0,0 +1,218 @@
+#!/bin/sh
+
+# cdda2flac TARGET_FOLDER
+#
+# Script to rip the inserted audio compact disc (CD) to a folder of
+# FLAC-compressed music files with original quality.
+#
+# Provide the wanted target folder as command line argument. It will be created
+# during execution.
+cdda2flac() {
+	folder="$1"
+	folder="$(realpath "${folder}")"
+	echo "Saving to ${folder}"
+
+	mkdir "${folder}"
+	return_path="$(pwd)"
+	cd "${folder}"
+
+	cdparanoia -B
+
+	find . -type f -iname '*.wav' -exec flac --delete-input-file {} \;
+
+	cd "${return_path}"
+
+	echo "\nDone! Files are saved to '${folder}'."
+}
+
+# cheat PROGRAM
+#
+# cheat gets the cheat sheet from https://cheat.sh about the given PROGRAM.
+cheat() {
+	curl "https://cheat.sh/${1}"
+}
+
+# radio STATION_NAME
+#
+# radio translates the STATION_NAME into a web radio URL via a user-provided
+# TSV file and starts to play the station's audio stream with mpv.
+radio() {
+	# constants
+	data_repo="${HOME}/.local/share/mydata"
+	data_rel="tables/radio.tsv"
+	data_abs="${data_repo}/${data_rel}"
+
+	# read station from command line arguments
+	station="$1"
+
+	# set a handler for keyboard interrupts
+	trap 'exit 0' 2 15
+
+	# check dependency and warn user if necessary
+	if ! command -v mpv > /dev/null 2>&1
+	then
+		echo 'You have to install mpv (e.g. sudo pacman -S mpv mpv-mpris)'
+		exit 1
+	fi
+
+	# check if data file exists
+	if ! [ -f "${data_abs}" ]
+	then
+		echo "Data file '""${data_abs}""' not found."
+		exit 1
+	fi
+
+	# translate sender name to URL
+	address="$(grep "${station}" "${data_abs}" | awk -F '\t' '{print $2}')"
+	if [ "${address}" = "" ]
+	then
+		echo "Could not translate station ${station} to URL."
+		exit 1
+	fi
+
+	# stream from address
+	echo "Streaming ${station} from ${address}."
+	mpv "${address}"
+}
+
+# showdot SOURCE [COMPILATION_ARGS]
+#
+# showdot displays a GraphViz source file (*.dot) with an image viewer. The
+# source code is converted into a temporary image file on the fly.
+showdot() {
+	# process arguments
+	code=$1
+	shift
+
+	file=$(mktemp)
+
+	# compile *.dot code to *.png
+	if ! dot "$@" -T png -o "${file}" "${code}"
+	then
+		echo "Failed to compile with GraphViz."
+		exit 1
+	fi
+
+	# launch image viewer
+	if ! sxiv "${file}"
+	then
+		echo "Failed to display generated image with sxiv."
+		exit 1
+	fi
+
+	rm "${file}"
+}
+
+# tv STATION_NAME
+#
+# tv translates the STATION_NAME into a tv stream URL via a user-provided TSV
+# file and starts to play the station's stream with mpv.
+tv() {
+	# constants
+	data_repo="${HOME}/.local/share/mydata"
+	data_rel="tables/tv.tsv"
+	data_abs="${data_repo}/${data_rel}"
+
+	# read station from command line arguments
+	station="$1"
+
+	# set a handler for keyboard interrupts
+	trap 'exit 0' 2 15
+
+	# check dependency and warn user if necessary
+	if ! command -v mpv > /dev/null 2>&1
+	then
+		echo 'You have to install mpv (e.g. sudo pacman -S mpv mpv-mpris)'
+		exit 1
+	fi
+
+	# check if data file exists
+	if ! [ -f "${data_abs}" ]
+	then
+		echo "Data file '""${data_abs}""' not found."
+		exit 1
+	fi
+
+	# translate sender name to URL
+	address="$(grep "${station}" "${data_abs}" | awk -F '\t' '{print $2}')"
+	if [ "${address}" = "" ]
+	then
+		echo "Could not translate station ${station} to URL."
+		exit 1
+	fi
+
+	# stream from address
+	echo "Streaming ${station} from ${address}."
+	mpv "${address}"
+}
+
+# url
+#
+# url opens a menu program with URL names saved in a user-provided TSV file and
+# opens the selected URL with a browser.
+url() {
+	# constants
+	data_repo="${HOME}/.local/share/mydata"
+	data_rel="tables/urls.tsv"
+	data_abs="${data_repo}/${data_rel}"
+
+	# check if data file exists
+	if ! [ -f "${data_abs}" ]
+	then
+		echo "Data file '""${data_abs}""' not found."
+		exit 1
+	fi
+
+	# select a menu program or panic
+	if command -v bemenu > /dev/null 2>&1
+	then
+		menu='bemenu'
+	elif command -v dmenu > /dev/null 2>&1
+	then
+		menu='dmenu'
+	elif command -v sxmo_dmenu.sh > /dev/null 2>&1
+	then
+		menu='sxmo_dmenu.sh'
+	else
+		echo 'You have to install bemenu, sxmo_dmenu.sh or dmenu!'
+		exit 1
+	fi
+
+	# check firefox dependency and warn user if necessary
+	if ! command -v firefox > /dev/null 2>&1
+	then
+		echo 'You have to install firefox.'
+		exit 1
+	fi
+
+	# let user select the URL
+	closer="[close menu]"
+	options="$(awk -F '\t' '{print $2}' < "${data_abs}" | sed "$ a ${closer}")"
+	key="$(echo "${options}" | ${menu} -i -l 10)"
+
+	# close if user selected the close entry or stopped menu with ESC
+	if [ "${key}" = "${closer}" ] || [ "${key}" = "" ]
+	then
+		exit 0
+	fi
+
+	# search for the selected key in data file
+	url=""
+	while read -r line
+	do
+		if [ "$(echo "${line}" | awk -F '\t' '{print $2}')" = "${key}" ]
+		then
+			if [ "${url}" = "" ]
+			then
+				url="$(echo "${line}" | awk -F '\t' '{print $1}')"
+			else
+				# warn if multiple URLs have this key
+				echo "More than one URL in data file matching selected key!" 1>&2
+				break
+			fi
+		fi
+	done < "${data_abs}"
+
+	# open selected URL in browser
+	firefox "${url}"
+}