#!/usr/bin/bash
# Copyright (c) 2012 fbt <fbt@fleshless.org>
# License: ISC
#
# About:
# A simple upload script for UFW (http://zerofiles.org)

_cat() {
	while read; do
		printf '%s\n' "$REPLY"
	done
}

is_url() {
	[[ "$1" =~ $cfg_url_regex ]]
}

msg() { printf '%s\n' "[ufw] $1"; }
err() { msg "(error) $1" >&2; }

usage() {
	_cat <<- EOF
		Usage: ufw [-RsF] [-D num] [file/url]"
		    Flags:
		        -R                   # Remove the file after uploading.
		        -s                   # Make a screenshot and upload it instead of a file.
		        -F                   # Make a fullscreen shot instead of prompting for a window/area. Implies -s.
		        -d                   # Supply a dexcription.
		        -D <num>             # Delay the shot by <num> seconds.
		        -p                   # Make the file public.
		        -u                   # Generate a shortlink from URL.
		        -m                   # Maximum filesize (takes K, M and G suffixes).
		        -a                   # Add the file to an album.
		
		    Config options (~/.config/ufw):
		        secret               # Your personal token. Get it at https://zfh.so/settings_form
		        cfg_screenshot_ext   # Screenshot file type, used by scrot.
				  cfg_max_filesize     # Maximum filesize in megabytes.
		        # Others are self-explanatory:
		        cfg_url_regex
		        cfg_tmp_dir
		        cfg_service_url
	EOF
}

ensure_env() {
	for i in "$cfg_tmp_dir"; do
		[[ -d "$i" ]] || { mkdir -p "$i"; }
	done
}

get_file_hash() {
	read file_hash _ < <( sha1sum "$1" )
}

get_max_filesize() {
	if [[ $cfg_max_filesize =~ ^[0-9]+[BKMG]?$ ]]; then
		max_filesize_base="${cfg_max_filesize//[BKMG]/}"

		case "$cfg_max_filesize" in
			*K) max_filesize_bytes=$(( max_filesize_base * 1024 ));;
			*M) max_filesize_bytes=$(( max_filesize_base * 1024 * 1024 ));;
			*G) max_filesize_bytes=$(( max_filesize_base * 1024 * 1024 * 1024 ));;
			*) max_filesize_bytes=$max_filesize_base;;
		esac
	else
		err "Wrong cfg_max_filesize: $cfg_max_filesize"
		return 1
	fi
}

upload() {
	if (( flag_scrot )); then
		flag_rm=1
		file=$(take_screenshot) || { return 1; }
	else
		(( $# )) || {
			usage
			return 1
		}

		target="$1"

		if is_url "$target"; then
			flag_rm=1
			file=$(_mktemp "$cfg_tmp_dir")

			get_max_filesize || { return 1; }

			curl --max-filesize "$max_filesize_bytes" -skL "$target" > "$file"
			curl_result=$?

			if (( curl_result )); then
				case "$curl_result" in
					63) err "File exceeds cfg_max_filesize";;
					*) err "Could not download file.";;
				esac

				return 1
			fi
		else
			file="$target"

			[[ -f "$file" ]] || {
				err "No such file: ${file}"
				return 1
			}
		fi
	fi

	get_file_hash "$file"

	curl -sL \
		-F file="@$file" \
		-F upload_mode='api' \
		-F flag_private="$flag_private" \
		-F short="$flag_shortlink" \
		-F secret="$secret" \
		-F submit="" \
		"${misc_curl_args[@]}" \
		-A 'zerofiles.org upload script' \
		"$cfg_service_url/upload"

	if (( $? )); then
		err 'Something has gone wrong with the upload.'
		return 7
	else
		if (( flag_rm )); then
			msg "Removing file: $file"
			rm "$file"
		fi
	fi
}

get_shortlink() {
	declare url=$1

	if ! curl -fsL "$cfg_service_url/api?mode=url_add&url=${url}&raw=1"; then
		err 'Something went wrong!'
	fi
}

take_screenshot() {
	declare tmp_file

	[[ "$scrot_exec" ]] || { scrot_exec=$(type -P scrot); }
	[[ "$scrot_exec" ]] || {
		err "Please install scrot to use this function"
		return 1
	}

	(( "$flag_scrot_fullscreen" )) || { scrot_args+=( '-s' ); }
	[[ "$cfg_scrot_delay" ]] && { scrot_args+=( "-d $cfg_scrot_delay" ); }

	tmp_file="$(_mktemp "${cfg_tmp_dir}" ".${cfg_screenshot_ext}")"

	scrot "${scrot_args[@]}" "$tmp_file" || {
		err "Failed to take a screenshot."
		return 1
	}

	printf '%s\n' "$tmp_file"
}

_mktemp() {
	declare tmp_file_name tmp_file_name_extra="$2" tmp_dir="$1" 

	[[ -d "$tmp_dir" ]] || {
		err "${tmp_dir} does not exist or is not a directory."
		return 1
	}

	until [[ ! -e "${tmp_dir}/${tmp_file_name}" ]]; do
		tmp_file_name="${RANDOM}${RANDOM}${tmp_file_name_extra}"
	done

	printf '%s\n' "${tmp_dir}/${tmp_file_name}"
}

get_my_ip() {
	my_ip=$( curl -fsL https://zfh.so/ip )

	if ! (( $? )); then
		printf '%s\n' $my_ip
	fi
}

set_argv() {
	declare arg opt c
	declare -g argv

	while (( $# )); do
		unset -v arg opt c

		case "$1" in
			(--) argv+=( "$1" ); break;;

			(--*)
				IFS='=' read arg opt <<< "$1"
				argv+=( "$arg" )

				[[ "$opt" ]] && {
					argv+=( "$opt" )
				}
			;;

			(-*)
				while read -n1 c
				do
					case "$c" in
						-|'') :;;
						*) argv+=( "-$c" );;
					esac
				done <<< "$1"
			;;

			(*) argv+=( "$1" );;
		esac
		shift
	done
}

main() {
	declare args file target flag_private flag_rm flag_scrot flag_scrot_fullscreen cfg_scrot_delay
	declare flag_shortlink=0

	# Defaults for XDG
	if ! [[ "$XDG_RUNTIME_DIR" ]]; then
		XDG_RUNTIME_DIR="/run/user/$UID"
	fi

	if ! [[ "$XDG_CONFIG_DIR" ]]; then
		XDG_CONFIG_DIR="$HOME/.config"
	fi

	cfg_url_regex='^[A-Za-z]([A-Za-z0-9+.-]+)?://.+'
	cfg_tmp_dir="$XDG_RUNTIME_DIR/ufw"; TEMPDIR="$cfg_tmp_dir"
	cfg_service_url='https://8fw.me'
	cfg_screenshot_ext='png'
	cfg_max_filesize='200M'

	if [[ -f "$HOME/.suprc" ]]; then
		printf 'Found legacy configfile, moving...\n' >&2
		mv "$HOME/.suprc" "$XDG_CONFIG_DIR/ufw"
	fi

	if [[ -f "$XDG_CONFIG_DIR/ufw" ]]; then
		if ! source "$XDG_CONFIG_DIR/ufw"; then
			printf 'Failed to source configuration file: %s\n' "$XDG_CONFIG_DIR/ufw"
			return $?
		fi
	fi

	while [[ "$1" ]]; do
		case "$1" in
			-p|--private) flag_private='false';;
			-R|--remove-file) flag_rm='1';;
			
			-s|--screenshot) flag_scrot='1';;
			-D|--screenshot-delay) cfg_scrot_delay="$2"; shift;;
			-F|--fullscreen)
				flag_scrot='1'
				flag_scrot_fullscreen='1'
			;;

			-i|--my-ip) action='getmyip';;

			-S|--short) flag_shortlink='1';;
			-u|--url) action='url';;

			-a|--album-id)
				misc_curl_args+=( -F "album_id=$2" )
				shift
			;;

			-A|--album-name)
				misc_curl_args+=( -F "album_name=$2" )
				shift
			;;

			-d|--description)
				misc_curl_args+=( -F "description=$2" )
				shift
			;;
			
			-h|--help|--usage) usage; return;;

			--) shift; break;;

			*) break;;
		esac
		shift
	done

	ensure_env

	case "${action:-upload}" in
		upload) upload "$1";;
		url) get_shortlink "$1";;
		getmyip) get_my_ip;;
	esac
}

set_argv "$@"
main "${argv[@]}"