#!/bin/bash

# ------------ Begin Configuration ------------ #
# The log file
LOG=/var/log/pacget.log
# Number of connections per server (don't go beyond 2, please)
CONNECTIONS=2
# Max number of servers to download from (follows ordering in include file)
SERVERS=4
# Maximum download speed (0 = unrestricted)
MAX_SPEED=0
# Minimum download speed (0 = don't care)
MIN_SPEED=0
# Maximum tries per download
MAX_TRIES=2
# Server timeout period
TIMEOUT=15
# Passive FTP or not: 'yes' or 'no'
FTP_PASV=no
# 'none' or 'prealloc'
FILE_ALLOC=none
#convert host to IP address if host resolves into multiple ip's: 'yes or 'no' (requires dnsutils, uses dig)
#(This resolves the error issue with aria2c)
CONVERT_TO_IP=no
# ------------- End Configuration ------------- #


ARIA2_BIN=$(which aria2c 2> /dev/null)

if [ ! -x ${ARIA2_BIN} ]; then
  echo "aria2c was not found or isn't executable."
  exit 1
fi

filename=$(basename ${1})
server=${1%/${filename}}

# Determine which repo is being used
if [ -n "$(grep "${server}" /etc/pacman.d/*)" ]; then
  repo=$(grep "${server}" /etc/pacman.d/* | cut -d ':' -f 1 | cut -d '/' -f 4)
else
  repo="testing_or_custom"
fi

# Override number of connections for db files
if [[ ${filename} = *.db.tar.gz ]]; then
  CONNECTIONS=1
fi

# For db files, or when using [testing] or a custom repo (which most likely doesn't have any mirror),
# use only the URL passed by pacman; Otherwise, extract the list of servers (from the include file of the repo) to download from
if [[ ${filename} = *.db.tar.gz || "${repo}" = "testing_or_custom" ]]; then
  url="${1}"
else
  url=$(sed -n 's/^Server = //; s,$,/'"${filename}"', ; /^ftp/p; /^http/p' /etc/pacman.d/${repo} | head -n ${SERVERS})
fi

#convert URL to IP
if [ "${CONVERT_TO_IP}" = "yes" ];then
  for mirror in $url;do
    host=$(cut -d/ -f3 <<<$mirror)
    if [[ $(dig +short $host|grep '^[0-9]'|wc -l) -gt 1 ]];then
      ip=$(dig +short $host|grep '^[0-9]'|head -n1)
      nurl+=$(sed "s,$host,$ip," <<<$mirror)' '
    else
      nurl+=$mirror
    fi
  done
  url=$nurl
fi

# Passive FTP or not?
[ "${FTP_PASV}" = "yes" ] && OPT_FTP_PASV="--ftp-pasv" || OPT_FTP_PASV=""

echo "Target: ${filename}"

${ARIA2_BIN} --log=${LOG} --timeout=${TIMEOUT} --max-tries=${MAX_TRIES} --allow-overwrite=true \
             --split=${CONNECTIONS} ${OPT_FTP_PASV} --file-allocation=${FILE_ALLOC} \
             --lowest-speed-limit=${MIN_SPEED} --max-download-limit=${MAX_SPEED} \
             ${url} --out=${filename}.pacget && [ ! -f ${filename}.pacget.aria2 ] && mv ${filename}.pacget ${2}

exit 0