#!/bin/bash

#

# Script to parse the non-text sources metadata file and download

# the required files from the lookaside cache

#

# Please note: this script is non-destructive, it wont replace

# files that already exist, regardless of their state, allowing you

# to have work-in-progress content that wont get overwritten.

#

# Might want to drop this in ~/bin/ and chmod u+x it

surl="https://git.centos.org/sources/"

# for setting any overrides, such as surl or f

if [ -f /etc/centos-git-common ]; then

  . /etc/centos-git-common

fi

#parse command line args

BRANCH=''

QUIET=''

CHECK=0

while (($# > 0))

do

  case $1 in

    --branch)

        #specify branch instead of asking git

        BRANCH=$2

        shift 2

        ;;

    --surl)

        #override sources url

        surl=$2

        shift 2

        ;;

    --check)

        #verify the sha1sum of the downloaded file

        CHECK=1

        shift

        ;;

     -q)

        # Be less chatty

        QUIET='--silent'

        shift

        ;;

  esac

done

# check metadata file and extract package name

found=0

shopt -s nullglob

for meta in .*.metadata

do

  pn=${meta%.metadata}

  pn=${pn#.}

  if [ -e "SPECS/$pn.spec" ]

  then

      found=1

      break

  fi

done

if (( $found != 1 ))

then

    echo 'Missing metadata or spec. Please run from inside a sources git repo'

    exit 1

fi

if [ ! -d .git ] || [ ! -d SPECS ]; then

  echo 'You need to run this from inside a sources git repo'

  exit 1

fi

mkdir -p SOURCES

# sort out our branch

if [ -n "$BRANCH" ]

then

  branches=("$BRANCH")

else

  # generate a list of all branches containing current HEAD

  branches=()

  while IFS='' read -r line

  do

    # input from: git branch --contains HEAD

    branch="${line:2}"

    if [[ "$branch" =~ "detached from" ]]

    then

      # ignore detached heads

      continue

    fi

    if [ ".${line:0:1}" = ".*" ]

    then

      # current branch, put it first

      branches=("$branch" "${branches[@]}")

    else

      branches=("${branches[@]}" "$branch")

    fi

  done <<< "$(git branch --contains HEAD)"

fi

while read -r fsha fname ; do

  if [ ".${fsha}" = ".da39a3ee5e6b4b0d3255bfef95601890afd80709" ]; then

    # zero byte file

    touch ${fname}

  else

    if [ ! -e "${fname}" ]; then

      for br in "${branches[@]}"

      do

        curl ${QUIET} -f "${surl}/${pn}/${br}/${fsha}" -o "${fname}" && break

      done

    else

      echo "${fname} exists. skipping"

    fi

    if [ ${CHECK} -eq 1 ]; then

        downsum=$(sha1sum ${fname} | awk '{print $1}')

        if [ ${fsha} != ${downsum} ]; then

            rm -f ${fname}

            echo "failed to download ${fname}" >&2

        fi

    fi

  fi

done < "${meta}"