#!/bin/bash
#
# sync-media assets using git-annex
#

REMOTE="$1"
VOLUME="/media/$REMOTE"
DOMAIN="`facter domain`"
HOST="`facter hostname`"
CACHE="/var/cache/$HOST/media"
MEDIA="media.$DOMAIN"
INCOMING="$CACHE/incoming"
WHOAMI="`whoami`"
OPTIONS="$*"

# Fix identity
function sync_media_identity {
  if [ -z "`git config --local user.email`" ] || [ -z "`git config --local user.name`" ]; then
    repo="$(basename `pwd`)"
    git config user.name "${repo^} Archive"
    git config user.email "$repo@localhost"
  fi
}

# Add files into the annex
function sync_media_add {
  git annex add .

  # Adding hidden files and symlinks, git+while version
  git status --porcelain -u | sed -e 's/?? //' | while read file; do
    if [ -h "$file" ]; then
      git add "$file"
    else
      git annex add "$file"
    fi
  done
}

# If there is a playlists folder, make sure mpd user can write to it
function sync_media_playlist_perms {
  if [ -d "playlists" ]; then
    $sudo chmod 775 playlists
    $sudo chown -R mpd.audio playlists
    find playlists -type f -exec sudo chmod 664 {} \;
    find playlists -type d -exec sudo chmod 775 {} \;
  fi
}

# Fix incoming permissions
function sync_media_incoming_perms {
  if [ -d "$INCOMING" ]; then
    echo "Fixing $INCOMING permissions..."
    $sudo find $INCOMING -type f -exec chmod 664 {} \;
    $sudo find $INCOMING -type d -exec chmod 775 {} \;
    $sudo chown -R $WHOAMI.incoming $INCOMING
  fi
}

# Run fsck
function sync_media_fsck {
  if [ "$FSCK" == "true" ]; then
    git annex fsck --fast
  fi
}

# Run dropunused
function sync_media_dropunused {
  if [ "$DROPUNUSED" == "true" ]; then
    git annex unused
    git annex dropunused 1-1000
  fi
}

# Get copies of annexed files
function sync_media_get {
  local repo="$1"
  local numcopies

  if [ "`git -C $repo config sync-media.get`" != "false" ]; then
    if git -C $repo config sync-media.numcopies &> /dev/null; then
      numcopies="`git -C $repo config sync-media.numcopies`"
    else
      numcopies="3"
    fi

    git annex get . --numcopies=$numcopies
  fi
}

# Control whether the repository should have a copy of everything
function sync_media_getall {
  local repo="$1"

  if [ "`git -C $repo config sync-media.getall`" == "true" ]; then
    git annex get .
  fi
}

# Ensure we have a reference to the remote repository
function sync_media_ensure_remote {
  local remote="$1"
  local path="$2"

  if [ -z "$remote" ] || [ -z "$path" ]; then
    return
  fi

  # Check for local or remote repo
  if [ -z "$DRIVE" ]; then
    path="$REMOTE.$DOMAIN:$path"
  elif [ ! -d "$path/.git/annex" ]; then
    return
  fi

  if ! git remote | grep -q "^$remote$"; then
    echo git remote add $remote $path
  fi
}

# Set sudo config
if [ "$WHOAMI" != 'root' ]; then
  sudo="sudo"
else
  echo "Sorry, cannot run as root"
  exit 1
fi

# Set fsck config
if echo $OPTIONS | grep -q -- "--fsck"; then
  FSCK="true"
fi

# Set unused config
if echo $OPTIONS | grep -q -- "--dropunused"; then
  DROPUNUSED="true"
fi

# Set drive config
if [ ! -z "$REMOTE" ]; then
  # Check storage media
  MOUNT="`mount | grep $VOLUME`"
  if [ ! -z "$MOUNT" ]; then
    DRIVE="$(basename `echo $MOUNT | awk '{ print $1 }'`)"
  fi
fi

# Commit changes
if [ -d "$CACHE" ]; then
  # Fix cache permissions
  #echo "Fixing $CACHE permissions..."
  #$sudo find $CACHE -type f -exec chmod 644 {} \;
  #$sudo find $CACHE -type d -exec chmod 755 {} \;

  sync_media_incoming_perms

  # Add and update local repositories
  for folder in `ls $CACHE`; do
    if [ -d "$CACHE/$folder/.git/annex" ]; then
      if [ "`git -C $CACHE/$folder config sync-media.skip`" == "true" ]; then
        continue
      fi

      #if [ "`git -C $CACHE/$folder config sync-media.ready`" != "true" ]; then
      #  echo "Skipping $CACHE/$folder: not sync-media ready, please config your repo."
      #  continue
      #fi

      (
      cd $CACHE/$folder
      echo "Syncing $CACHE/$folder..."

      sync_media_playlist_perms
      sync_media_ensure_remote $REMOTE $VOLUME/$MEDIA/$folder
      sync_media_identity
      sync_media_add
      git annex sync
      sync_media_getall $CACHE/$folder
      sync_media_fsck
      sync_media_dropunused
      )
    fi
  done

  if [ ! -z "$DRIVE" ]; then
    if [ ! -d "$VOLUME/$MEDIA" ]; then
      echo "Folder $VOLUME/$MEDIA does not exist..."
    else
      for folder in `ls $CACHE`; do
        if [ -d "$CACHE/$folder/.git/annex" ]; then
          if [ "`git -C $CACHE/$folder config sync-media.skip`" == "true" ]; then
            continue
          fi

          #if [ "`git -C $CACHE/$folder config sync-media.ready`" != "true" ]; then
          #  echo "Skipping $CACHE/$folder: not sync-media ready, please config your repo."
          #  continue
          #fi

          if [ ! -d "$VOLUME/$MEDIA/$folder" ]; then
            (
            cd $VOLUME/$MEDIA
            echo "Initializing $VOLUME/$MEDIA/$folder..."
            git clone $CACHE/$folder && cd $folder && sync_media_identity && git annex init $DRIVE && \
              git remote rename origin $HOST && cd $CACHE/$folder && git remote add $DRIVE $VOLUME/$MEDIA/$folder
            )
          fi
        elif [ ! -d "$VOLUME/$MEDIA/$folder" ]; then
          if [ ! -e "$CACHE/$folder/.sync-media/skip" ]; then
            echo "Syncing $VOLUME/$MEDIA/$folder..."
            rsync -av --delete --exclude=.sync-media $CACHE/$folder/ $VOLUME/$MEDIA/$folder/
          fi
        fi
      done
    fi
  fi
fi

# Retrieve changes at media volumes
if [ ! -z "$DRIVE" ] && [ -d "$VOLUME/$MEDIA" ]; then
  for folder in `ls $VOLUME/$MEDIA`; do
    if [ -d "$VOLUME/$MEDIA/$folder/.git/annex" ]; then
      if [ "`git -C $VOLUME/$MEDIA/$folder config sync-media.skip`" == "true" ]; then
        continue
      fi

      (
      cd $VOLUME/$MEDIA/$folder
      echo "Syncing $VOLUME/$MEDIA/$folder..."

      sync_media_ensure_remote $HOST $CACHE/$folder
      sync_media_playlist_perms
      sync_media_identity
      sync_media_add
      git annex sync
      sync_media_get    $VOLUME/$MEDIA/$folder
      sync_media_getall $VOLUME/$MEDIA/$folder
      sync_media_fsck
      sync_media_dropunused
      #git annex drop --auto --numcopies=2
      )
    elif [ -d "$CACHE/$folder" ]; then
      if [ ! -e "$CACHE/$folder/.sync-media/skip" ]; then
        echo "Syncing $VOLUME/$MEDIA/$folder..."
        rsync -av --delete --exclude=.sync-media $CACHE/$folder/ $VOLUME/$MEDIA/$folder/
      fi
    fi
  done
elif [ ! -z "$REMOTE" ]; then
  # Try to copy to a remote
  for folder in `ls $CACHE`; do
    if [ -d "$CACHE/$folder/.git/annex" ]; then
      if [ "`git -C $CACHE/$folder config sync-media.skip`" == "true" ]; then
        continue
      fi

      sync_media_ensure_remote $REMOTE $CACHE/$folder

      (
      cd $CACHE/$folder
      git annex copy . --to $REMOTE
      git annex sync
      )
    else
      if [ ! -e "$CACHE/$folder/.sync-media/skip" ]; then
        echo "Syncing $VOLUME/$MEDIA/$folder..."
        rsync -av --delete --exclude=.sync-media $CACHE/$folder/ $REMOTE.$DOMAIN:$CACHE/$folder/
      fi
    fi
  done
fi