From ebb7a3d10a3f16c9c5401ba03071193e97a3afb8 Mon Sep 17 00:00:00 2001
From: Martin Winkler <efelon@winklerfamilie.eu>
Date: Wed, 9 Mar 2022 00:22:03 +0100
Subject: [PATCH] Add ability to source catmd.sh itself (providing catmd() also
 as function)

Outsourced line reading function to linefeeder
---
 catmd.sh                 | 61 +++++++++++++++++++++-------------------
 linefeeder/linefeeder.sh | 32 +++++++++++++++++++++
 2 files changed, 64 insertions(+), 29 deletions(-)
 create mode 100755 linefeeder/linefeeder.sh

diff --git a/catmd.sh b/catmd.sh
index 6ecd03c..f3266a6 100755
--- a/catmd.sh
+++ b/catmd.sh
@@ -1,5 +1,7 @@
 #!/bin/bash
 
+# Script to beautify markdown syntax on command line
+
 DEBUG=:
 #DEBUG=echo
 
@@ -311,34 +313,6 @@ parseline() {
   printf "\n"
 }
 
-catmd() {
-  for arg in "$@"; do
-    case "$1" in 
-      -)
-        # treat - as input stream
-        break;;
-      -*)
-        # Ignore args for now
-        shift;;
-    esac
-  done
- 
-  local line=
-  local myargs=("$@")
-
-  # Use standard input if now files are present
-  [ $# -eq 0 ] && myargs[0]="/dev/stdin"
-  
-  for file in "${myargs[@]}"; do
-    [ "$file" == "-" ] && file="/dev/stdin"
-    while IFS='' read -r line; do 
-      parseline "$line"
-    done <"${file}"
-    # If last line in a file has no newline, read ends but still populates $line
-    [[ $line ]] && parseline "$line"
-    echo -en "$FO_RESET"
-  done
-}
 
 ## Font formating
 FO_RESET=$(tput sgr0)
@@ -401,4 +375,33 @@ FO_LINKURL="${FO_UL}"
 FO_CODEBLOCK="$COF_LIGHTGRAY$COB_LIGHTGRAY"
 FO_QUOTE='\033[96;100m'
 
-catmd "$@"
+# Use linefeeder for input handling
+WDIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" >>/dev/null 2>&1 && pwd)"
+source ${WDIR}/linefeeder/linefeeder.sh
+
+# Provide catmd also as function if this script is sourced
+catmd() {
+  linefeeder "$@"
+  echo -en "$FO_RESET"
+}
+
+### Check if script is sourced
+### https://stackoverflow.com/a/28776166
+sourced=0
+if [ -n "$ZSH_EVAL_CONTEXT" ]; then
+  case $ZSH_EVAL_CONTEXT in *:file) sourced=1;; esac
+elif [ -n "$KSH_VERSION" ]; then
+  [ "$(cd $(dirname -- $0) && pwd -P)/$(basename -- $0)" != "$(cd $(dirname -- ${.sh.file}) && pwd -P)/$(basename -- ${.sh.file})" ] && sourced=1
+elif [ -n "$BASH_VERSION" ]; then
+  (return 0 2>/dev/null) && sourced=1
+else # All other shells: examine $0 for known shell binary filenames
+  # Detects `sh` and `dash`; add additional shell filenames as needed.
+  case ${0##*/} in sh|dash) sourced=1;; esac
+fi
+###
+
+# Run directly only if not sourced
+if [ $sourced -eq 0 ]; then
+  linefeeder "$@"
+  echo -en "$FO_RESET"
+fi
diff --git a/linefeeder/linefeeder.sh b/linefeeder/linefeeder.sh
new file mode 100755
index 0000000..086eef9
--- /dev/null
+++ b/linefeeder/linefeeder.sh
@@ -0,0 +1,32 @@
+#!/bin/bash
+
+# define parseline() in the sourcing script
+
+linefeeder() {
+  for arg in "$@"; do
+    case "$1" in 
+      -)
+        # treat - as input stream
+        break;;
+      -*)
+        # Ignore options for now
+        shift;;
+    esac
+  done
+
+  local file= 
+  local line=
+  local args=("$@")
+
+  # Use standard input if no files are present
+  [ $# -eq 0 ] && args[0]="/dev/stdin"
+  
+  for file in "${args[@]}"; do
+    [ "$file" == "-" ] && file="/dev/stdin"
+    while IFS='' read -r line; do 
+      parseline "$line"
+    done <"${file}"
+    # If last line in a file has no newline, read ends but still populates $line
+    [[ $line ]] && parseline "$line"
+  done
+}