bin/pdf

#!/bin/bash
# Author: Skiqqy
# Basically solves any problem that has to do with pdfs
# Usage: pdf -h

args=("$@")
SCRIPT_PATH=$(dirname "$0")
com="mupdf -C FFDED7 -I"
# shellcheck source=./import/alert.sh
. "$SCRIPT_PATH/import/alert.sh" > /dev/null 2>&1
. "$SCRIPT_PATH/import/stdlib.sh" > /dev/null 2>&1

[ ! "$(command -v error)" ] && echo "[WARNING] Missing 'error.sh' import."
[ ! "$(command -v mupdf)" ] && warning "Missing 'mupdf' dependency." 1

# Keep track of what needs to be done.
TODO ()
{
cat << EOF
pdf ~ TODO Tracker
------------------

TODO: Fix argument passing to only set vars, not run functions, as this is bad style.
	- Reason: Program can 'break' if arguments are passed in a wierd order.

TODO: During refactor some of the optorgs broke, this is due to not doing the above TODO, fix
EOF
}

usage ()
{
cat << EOF
pdf ~ An easy way to deal with pdfs
-----------------------------------

Usage: pdf [options] [command] file

Options
-------
-h			Shows this message.
-o			Specify output file when compiling a pdf.
-p			Use dmenu to enter a password for the pdf.
-v			Specify which pdf viewer you want to use.
-e			Use gimp to edit a pdf.
-d			Use mutool (from mupdf) to decompile a pdf.
-c			Compile a pdf and then open it, Supported file type(s) include:
			 - .md
			 - .tex
			 - .1 (man pages)
-t			Generate a .tex skeleton document.
--TODO			Lists current TODO's.
--output=<FILENAME>	Specify outputfile when compiling a pdf.

Commands
--------
exec        Attempt to compile a file, or open a pdf.
watch       Watch a pdf, and refresh mupdf if a change is detected.

Example(s)
----------
\$ pdf https://skiqqy.xyz/assets/CurriculumVitae.pdf # Download and open pdf
\$ pdf some.pdf # open pdf
\$ pdf document.tex # Compile a tex file to 'document.pdf'
\$ pdf document.md  # Compile a md file to 'document.pdf'
\$ pdf -c document.md  # Compile a md file to 'document.pdf' and then open it

Author: Skiqqy
EOF
	exit "$1"
}

fetch_pdf ()
{
	index=$((${#args[@]} - 1))
	url="${args[$index]}"

	# Check to see if we need to download the pdf
	if [[ "$url" =~ ^http(s)?:// ]]
	then
		file=$(basename "$url")
	else
		file="$url"
		url=
	fi
	extension=$(echo "$file" | cut -d "." -f 2)

	if [ "$extension" == "pdf" ]
	then
		if [ -z $url ]
		then
			$com "$file"
		else
			curl -s "$url" > /tmp/"$file"
			$com /tmp/"$file"
		fi
	else
		error "Invalid file type."
	fi
}

# Usage: build_tex "file_name"
# Note: will, if we call with "file_name", then it will also use a "file_name.bib" when building, if it exists
build_tex ()
{
	[ ! "$(command -v pdflatex)" ] && error "Missing 'pdflatex', cannot build from .tex"
	pdflatex "$1".tex && biber "$1"; pdflatex "$1".tex && pdflatex "$1".tex
	[ ! -f "$1.bib" ] && warning "\'$1.bib\' not found, skipped."
	rm -f "$1."{'aux','bbl','bcf','blg','log','xml','nav','out','snm','toc'} && success "Cleaned build files."

	if [ -n "$out" ]
	then
		[ "$(echo "$out" | cut -d\. -f 2)" = pdf ] && out="$(echo "$out" | cut -d\. -f 1)"
		mv "$1.pdf" "$out.pdf"
	fi
}

# Usage: build_md "file_name"
# Compiles file_name.md to file_name.pdf
build_md ()
{
	[ ! "$(command -v pandoc)" ] && error "Missing 'pandoc', cannot build from .md"
	if [ -z "$out" ]
	then
		out="$1"
	else
		[ "$(echo "$out" | cut -d\. -f 2)" = pdf ] && out="$(echo "$out" | cut -d\. -f 1)"
	fi

	# Compile
	pandoc "$1.md" -o "$out.pdf" && success "Compiled \'$1.md\'."
}

# Usage: build_man_page "file_name"
# Compiles file_name.1 to file_name.pdf
build_man_page ()
{
	[ ! "$(command -v ps2pdf)" ] && error "Missing 'ps2pdf', cannot build from .1"
	if [ -z "$out" ]
	then
		out="$1"
	else
		[ "$(echo "$out" | cut -d\. -f 2)" = pdf ] && out="$(echo "$out" | cut -d\. -f 1)"
	fi

	# Compile
	man -t <(cat "$1.1") | ps2pdf - "$out.pdf"
}

parse_build ()
{
	[ -z "$file" ] && [ -z "$ftype" ] && warning "Missing file." && usage 1
	[ ! -f "$file.$ftype" ] && error "\'$file.$ftype\' not found."
	case $ftype in
		tex)
			build_tex "$file"
			;;
		md)
			build_md "$file"
			;;
		1)
			build_man_page "$file"
			;;
		*)
			error "Unknown file extension."
			;;
	esac
}

gen_tex_skelly ()
{
cat << EOF
\documentclass{article}

\\title{TITLE}
\\author{$USER}
\date{\\today}

\\begin{document}
\maketitle
\\tableofcontents

\\section{Introduction}
\\end{document}
EOF
}

main ()
{
	while getopts "hpcv:o:edt-:" opt
	do
		case "$opt" in
			-)
				case "$OPTARG" in
					TODO)
						TODO
						return 0
						;;
					output=*)
						out=${OPTARG#*=}
						;;
					*)
						error "Invalid arg, use -h for help." 1
						;;
				esac
				;;
			h)
				usage 0
				;;
			p)
				[ ! "$(command -v dmenu)" ] && error "Missing 'dmenu' dependency." 1
				pass=$(prompt "PDF Password:")
				com="$com -p $pass"
				;;
			c)
				parse_build
				index=$((${#args[@]} - 1))
				url="${args[$index]}"
				if [ -z "$out" ]
				then
					args["$index"]="$(echo "$url" | cut -d\. -f 1).pdf"
				else
					[ "$(echo "$out" | cut -d\. -f 2)" = pdf ] && out="$(echo "$out" | cut -d\. -f 1)"
					args["$index"]="$out.pdf"
				fi
				fetch_pdf
				return 0
				;;
			v)
				com="$OPTARG"
				;;
			e)
				[ ! "$ftype" = "pdf" ] && error "Not a pdf!"
				gimp "${args[$index]}"
				return 0
				;;
			d)
				[ ! "$ftype" = "pdf" ] && error "Not a pdf!"
				file="${args[$index]}"
				mutool clean -d "$file" "decompiled-$file"
				return 0
				;;
			t)
				gen_tex_skelly
				return 0
				;;
			o)
				out="$OPTARG"
				;;
			*)
				error "Invalid arg, use -h for help." 1
				;;
		esac
	done
	shift $((OPTIND-1)) # Get rid of parsed optargs

	if [[ $1 =~ \. ]]
	then
		command=exec
	else
		command="$1"
		shift 1
	fi

	[ ! "$command" = help ] && [ -z "$1" ] && \
		warning 'Missing file argument\n' && usage 1
	case "$command" in
		exec)
			base=$(basename "$1" 2>/dev/null)
			ftype=$(echo "$base" | cut -d\. -f 2)
			file=$(echo "$base" | cut -d\. -f 1)

			# Detect what we must do, based on file extension.
			case $ftype in
				pdf)
					fetch_pdf # We open if the extension is .pdf
					;;
				*)
					parse_build # If the extionsion is not .pdf, we attempt to build it
					;;
			esac
			;;
		watch)
			[ ! -f "$1" ] && error "'$1' DNE!"
			while inotifywait -e close_write "$1"
			do
				pkill -HUP mupdf
			done
			;;
		help)
			usage 0
			;;
		*)
			usage 1
			;;
	esac
}

main "$@"