#!/bin/bash
#
# Usage: update-mirror <url of upstream> <local project dirname>
#
# Derived from girocco's taskd/clone.sh script.  See
# http://repo.or.cz/w/girocco.git

set -e

cfg_gitweburl=http://$(hostname)/gitweb
cfg_reporoot=/var/lib/git/mirrors

url=$1
projdir=$2

proj="${projdir%.git}"

echo "[$proj] update mirror"
echo "[$proj] $url -> $projdir"

if [ ! -d "$cfg_reporoot/$projdir" ]; then
  echo "[$proj] $projdir is a new project"
  mkdir -p "$cfg_reporoot/$projdir"
  touch "$cfg_reporoot/$projdir/.new_clone"
fi
touch "$cfg_reporoot/$projdir/.clone_in_progress"

cd "$cfg_reporoot/$projdir"
trap "echo \"[$proj] clone failed\"; touch .clone_failed" EXIT

mail="sysadmin"

# Initial mirror
echo "[$proj] mirroring..."
case "$url" in
  svn://* | svn+http://* | svn+https://*)
    # we just remove svn+ here, so svn+http://... becomes http://...
    svnurl="${url#svn+}"
    if [ -f "$cfg_reporoot/$projdir/.new_clone" ]; then
      echo "[$proj] initial git-svn setup"
      git --git-dir . --bare init
      git --git-dir . svn init -s --prefix=svn-origin/ "$svnurl"
      # have git-svn store branches under svn-origin/heads/* not svn-origin/*
      # FIXME: may need to do similar when new branches are added
      git --git-dir . config svn-remote.svn.branches \
	  "$(git config --get svn-remote.svn.branches | \
	  sed 's|:refs/remotes/svn-origin/\*$|:refs/remotes/svn-origin/heads/*|')"
      git --git-dir . svn fetch
      # Neat Trick suggested by Miklos Vajna
      git --git-dir . config remote.origin.url .
      git --git-dir . config remote.origin.fetch \
	  '+refs/remotes/svn-origin/heads/*:refs/heads/*'
      git --git-dir . config --add remote.origin.fetch \
	  '+refs/remotes/svn-origin/trunk:refs/heads/master'
      git --git-dir . config --add remote.origin.fetch \
	  '+refs/remotes/svn-origin/tags/*:refs/tags/*'
      rm -f "$cfg_reporoot/$projdir/.new_clone"
    fi
    echo "[$proj] fetching new commits from upstream"
    git --git-dir . svn fetch
    git --git-dir . fetch
    ;;

  darcs://*)
    echo "[$proj] darcs mirrors not yet supported"
    exit 1
    httpurl="${url/darcs:\/\//http://}"
    /usr/bin/darcs-fast-export --export-marks=$(pwd)/dfe-marks "$httpurl" | \
	git fast-import --export-marks=$(pwd)/gfi-marks
    # This is here because by default only the exit code of
    # git fast-import is checked
    [ ${PIPESTATUS[0]} = 0 -a ${PIPESTATUS[1]} = 0 ]
    ;;

  bzr://*)
      echo "[$proj] bazaar mirrors not yet supported"
      exit 1
      # we just remove bzr:// here, a typical bzr url is just
      # "lp:foo"
      bzrurl="${url#bzr://}"
      bzr fast-export --export-marks=$(pwd)/bfe-marks "$bzrurl" | \
	  git fast-import --export-marks=$(pwd)/gfi-marks
      [ ${PIPESTATUS[0]} = 0 -a ${PIPESTATUS[1]} = 0 ]
      ;;

  *)
    if [ -f "$cfg_reporoot/$projdir/.new_clone" ]; then
      echo "[$proj] initial git setup"
      git --git-dir . --bare init
      git --git-dir . remote rm origin >/dev/null 2>&1 || :
      git --git-dir . remote add --mirror origin "$url"
    fi
    echo "[$proj] fetching new commits from upstream"
    git --git-dir . remote update
    git --git-dir . remote prune origin
    ;;
esac

# The rest
git update-server-info
trap "" EXIT
rm .clone_in_progress
echo "[$proj] clone updated.  See $cfg_gitweburl/?p=mirrors/$projdir;a=summary"