#!/bin/bash
########################################################################
#  Copyright (C) 2019 Max Mehl <mail@mehl.mx>
########################################################################
#  
#  This program is free software: you can redistribute it and/or modify
#  it under the terms of the GNU General Public License as published by
#  the Free Software Foundation, either version 3 of the License, or
#  (at your option) any later version.
#  
#  This program is distributed in the hope that it will be useful,
#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#  GNU General Public License for more details.
#  
#  You should have received a copy of the GNU General Public License
#  along with this program.  If not, see <http://www.gnu.org/licenses/>.
#  
########################################################################
#  
#  This script enables users to easily upload files via a SSH connection
#   and creates a link to download them.
#  
########################################################################


BASENAME=$(basename "$0")

# Load config
BINDIR="$(dirname "$(readlink -f "$0")")"
# Test if config.cfg exists and set needed variables
if [ ! -e "$BINDIR"/config.cfg ]; then echo "Missing config.cfg file. Edit and rename config.cfg.sample"; exit 1; fi
source "$BINDIR"/config.cfg

if [ "$1" = "" ]; then
	echo "Usage: $BASENAME <file-to-upload>"
	exit 1
fi

# Transform to full path
# file.pdf or /path/to/file.pdf
FILE="$1"
# -> file.pdf
FILE_NAME="$(basename "${FILE}")"
# -> file
FILE_PREFIX="${FILE_NAME%.*}"
# .pdf
FILE_SUFFIX="$([[ "$FILE_NAME" = *.* ]] && echo ".${FILE_NAME##*.}" || echo '')"

# Check whether file actually exists locally
if [ ! -e "${FILE}" ]; then
    echo "File ${FILE} does not exist locally."
    exit 1
fi

# If the file already exists on the host, append a number and iterate if necessary
i=0
FILE_PREFIX_tmp="${FILE_PREFIX}"
while [ "$ok" != "y" ]; do
  # constuct file name, and replace spaces by underscores
  DEST="$(echo "$FILE_PREFIX_tmp$FILE_SUFFIX" | sed 's/ /_/g')"
  # Check if file is existent remotely
  cmd="test -e \"${SSH_PATH}\"/\"${DEST}\""
  # If file does already exist with this name
  if ssh -q "${SSH_HOST}" "${cmd}"; then
    # iterate number and append -<number> to file name in front of suffix
    ((i++))
    FILE_PREFIX_tmp="$FILE_PREFIX"-${i}
    ok=n
  # If file does not exist yet
  else
    # Only output this info if a rename took place
    if [[ $i -gt 0 ]]; then
      echo "A file with an identical name already exists in the remote directory."
      echo "Your file has been renamed to prevent overwriting."
      echo
    fi
    ok=y
  fi
done

# Upload file
scp "$FILE" "${SSH_HOST}":"${SSH_PATH}"/"${DEST}"

# Output download link
echo "File has been uploaded. Download link:"
echo "$URL/$DEST"

exit 0