refactor: improve templater with new functionality

Misc/Templater.bash

@@ -1,20 +1,128 @@
 #!/usr/bin/env bash
 
-# "Import" our needed functions from our library
+echo_rgb() {
-LIBRARY_PATH="/usr/local/lib/Custom-Scripts"
+	# Echo a colored string to the terminal based on rgb values
-# shellcheck source=/usr/local/lib/
+	#
-if ! source "${LIBRARY_PATH}/Logging-RGB.bash"; then
+	# Positional Arguments:
-  echo "Unable to source Logging-RGB.bash at ${LIBRARY_PATH}"
+	#
-  exit 1
+	#   message <type: string> <position: 1> <required: true>
-fi
+	#     - The message to be printed to stdout
-# shellcheck source=/usr/local/lib/
+	#   red <type: int> <position: 2> <required: true>
-if ! source "${LIBRARY_PATH}/Trim.bash"; then
+	#     - The red value from 0 to 255
-  log "error" "Unable to source Trim.bash at ${LIBRARY_PATH}"
+	#   green <type: int> <position: 3> <required: true>
-  exit 1
+	#     - The green value from 0 to 255
-fi
+	#   blue <type: int> <position: 4> <required: true>
+	#     - The blue value from 0 to 255
+	#
+	# Usage:
+	#   echo_rgb "Yep" 10 8 30
+	#
+	# POSIX Compliant:
+	#   N/A
+	#
 
-# Tmp file used because most distros have this dir exist in RAM, use PID of our process to write to
+	local red
-TEMP_FILE="/tmp/$$"
+	local green
+	local blue
+	local input
+
+	input="${1}"
+	red="${2}"
+	green="${3}"
+	blue="${4}"
+
+	if [ -t 1 ]; then
+		printf "\e[0;38;2;%s;%s;%sm%s\e[m\n" "${red}" "${green}" "${blue}" "${input}"
+	else
+		printf "%s\n" "${input}"
+	fi
+}
+
+log() {
+	# Print a message and send it to stdout or stderr depending upon log level, also configurable with debug etc.
+	#
+	# Arguments:
+	#   level <type: string> <position: 1> <required: true>
+	#     - The log level, defined within a case check in this function
+	#   message <type: string> <position: 2> <required: true>
+	#     - The info message
+	#   line_number <type: int> <position: 3> <required: false>
+	#     - The line number of the calling function (${LINNO})
+	#
+	# Usage:
+	#   log "info" "Could not find that directory"
+	#
+	# POSIX Compliant:
+	#   Yes
+	#
+
+	# Set debug status depending if a global debug variable has been set to either 1 or 0
+	local debug
+	if [ ${DEBUG} ]; then
+		debug=${DEBUG}
+	else
+		debug=0
+	fi
+
+	local FORMAT
+	FORMAT="[$(echo_rgb "$(date +%Y-%m-%dT%H:%M:%S)" 180 140 255)]"
+
+	# Convert the level to uppercase
+	local level
+	level=$(echo "${1}" | tr '[:lower:]' '[:upper:]')
+
+	local message
+	message="${2}"
+
+	case "${level}" in
+	INFO)
+		# Output all info log levels to stdout
+		printf "${FORMAT}[$(echo_rgb "INFO" 0 140 255)] %s\n" "${message}" >&1
+		return 0
+		;;
+	WARN | WARNING)
+		# Output all warning log levels to stdout
+		printf "${FORMAT}[$(echo_rgb "WARNING" 255 255 0)] %s\n" "${message}" >&1
+		return 0
+		;;
+	DEBUG)
+		# Output all debug log levels to stdout
+		if [ "${DEBUG}" ]; then
+			printf "${FORMAT}[$(echo_rgb "DEBUG" 0 160 110)] %s\n" "${message}" >&1
+		fi
+		return 0
+		;;
+	ERROR)
+		# Output all error log levels to stderr
+		printf "${FORMAT}[$(echo_rgb "ERROR" 255 0 0)] %s\n" "${message}" >&2
+		return 0
+		;;
+	# Further log levels can be added by extending this switch statement with more comparisons
+
+	*) # Default case, no matches
+		# Returns non-zero code as an improper log option was passed, this helps with using `set -e`
+		printf "${FORMAT}[ERROR] %s\n" "Invalid log level passed, received level \"${level}\" with message \"${message}\"" >&2
+		return 1
+		;;
+	esac
+}
+
+trim() {
+	local input="${1}"
+
+	while [[ "${input}" == " "* ]]; do
+		input="${input## }"
+	done
+
+	while [[ "${input}" == *" " ]]; do
+		input="${input%% }"
+	done
+
+	echo "${input}"
+}
+
+# Get a temp working file so we don't pollute directories
+TEMP_FILE="$(mktemp)"
 
 # Set the Contents directory to the env variable, script set, or to their .contents file in the user home
 CONTENTS_DIRECTORY="${CONTENTS_DIRECTORY:=\
@@ -32,6 +140,8 @@ template_handlers=(
 	["FILE"]="file_handler"
 	["WRITE-TO"]="write_to_handler"
 	["TEMPLATE"]="template_handler"
+	["VAR"]="var_handler"
+	["EVAL"]="eval_handler"
 )
 
 write_content() {
@@ -43,7 +153,7 @@ write_content() {
 	local string_builder
 	string_builder=""
 
-  for ((i=1; i<=leading_spaces; i++)); do
+	for ((i = 1; i <= leading_spaces; i++)); do
 		string_builder="${string_builder} "
 	done
 	string_builder="${string_builder}${content}"
@@ -52,11 +162,27 @@ write_content() {
 
 _write_to_buffer() {
 	log "debug" "Received content to write to buffer:
-${1}"
+	${1}"
-  printf "%s\n" "${1}" >> "${TEMP_FILE}"
+	printf "%s\n" "${1}" >>"${TEMP_FILE}"
 	log "debug" "Finished writing content to buffer"
 }
 
+var_handler() {
+	local variable="${1}"
+	local leading_spaces="${2}"
+	while IFS="\n" read -r line; do
+		write_content "${line}" "${leading_spaces}"
+	done <<<"${variable}"
+}
+
+eval_handler() {
+	local eval_statement="${1}"
+	local leading_spaces="${2}"
+	while IFS="\n" read -r line; do
+		write_content "${line}" "${leading_spaces}"
+	done <<<"$(eval "${eval_statement}")"
+}
+
 template_handler() {
 	local template_file
 	template_file="${1}"
@@ -88,7 +214,6 @@ file_handler() {
 		file="${CONTENTS_DIRECTORY}/${file}"
 	fi
 
-
 	if [[ ! -f "${file}" ]]; then
 		log "error" "The given file \"${file}\" does not exist"
 		return 1
@@ -96,10 +221,9 @@ file_handler() {
 
 	while IFS="\n" read -r line; do
 		write_content "${line}" "${leading_spaces}"
-  done < "${file}"
+	done <"${file}"
 }
 
-
 write_to_handler() {
 	local write_path
 	write_path=${1}
@@ -128,7 +252,7 @@ parse_template_extracted() {
 	full_line="${2}"
 
 	local num_leading_spaces
-  num_leading_spaces=$(awk -F"[ ]" '{for(i=1;i<=NF && ($i=="");i++);print ""i-1""}' <<< "${full_line}")
+	num_leading_spaces=$(awk -F"[ ]" '{for(i=1;i<=NF && ($i=="");i++);print ""i-1""}' <<<"${full_line}")
 
 	# Basic checks to ensure template is correct, first not empty, second that an '=' was passed to give type specifier
 	# third is to ensure only one equals sign is passed
@@ -214,7 +338,7 @@ read_template() {
 		# Check for non zero status code
 		if ! parse_template_line "${line}"; then
 			log "error" "Invalid template passed from \"${read_file}\", check line ${line_num}"
-      if (( "${EXIT_ON_ERROR}" == 0 )); then
+			if (("${EXIT_ON_ERROR}" == 0)); then
 				exit 1
 			fi
 		fi
@@ -231,7 +355,7 @@ templater() {
 
 	read_template "${read_file}"
 
-  if (( "${REPEAT}" == 0 )); then
+	if (("${REPEAT}" == 0)); then
 		REPEAT=1
 		log "debug" "Repeat set to 0, repeating on the finished file located at ${TEMP_FILE}"
 		mv "${TEMP_FILE}" "${TEMP_FILE}-repeat"
@@ -248,11 +372,11 @@ arg_required() {
 	echo_rgb "${1}" 255 183 0
 }
 
-arg_optional(){
+arg_optional() {
 	echo_rgb "${1}" 117 255 255
 }
 
-arg_description(){
+arg_description() {
 	echo_rgb "${@}" 220 190 255
 }
 

Misc/Templater.md

@@ -21,3 +21,28 @@ For example
   For example, say we have a primary template `main.tmpl` that uses the sub-template `sub.tmpl` then
   when the parsing process begins it will also parse the contents of `sub.tmpl` and append them to the contents
   parsed by `main.tmpl`
+- VAR
+  - This is used when you want to expand a variable from your environment, say "${HOME}"
+- EVAL
+  - This is used when you want to evaluate a statement in bash, be careful as any errors here can really nuke things and
+    cause security issues.
+
+
+## Example
+
+Given a template file with content like so:
+
+```
+{#% VAR=$HOME %#}
+{#% EVAL="ls -alh" %#}
+```
+
+The output would be something like
+```
+/home/username
+total 52K
+drwxr-xr-x 1 sam sam  196 Sep 15 17:03 .
+drwxr-xr-x 1 sam sam   94 Sep 15 16:42 ..
+-rwxr-xr-x 1 sam sam  13K Sep 15 17:01 Templater.bash
+-rw-r--r-- 1 sam sam 1.1K Sep 15 17:03 Templater.md
+```