#!/bin/sh

: ${RCM_LIB:=`dirname $0`/../share/rcm}
. $RCM_LIB/rcm.sh

pushdir() {
  DIR_STACK="$DIR_STACK:$PWD/$1"
  $DEBUG "cd'ing to $1 from `pwd` with stack $DIR_STACK"
  cd $1
}

popdir() {
  current=`echo $DIR_STACK | sed -e 's/.*://g'`
  prior=`echo $DIR_STACK | sed -e "s|:$current$||" | sed -e 's/.*://g'`
  DIR_STACK=`echo $DIR_STACK | sed -e 's/:[^:]*$//'`
  $DEBUG "cd'ing to $prior from `pwd` with stack $DIR_STACK"
  cd $prior
}

build_path() {
  local dest="$1"
  local file="$2"
  local dotted=$3

  if [ $dotted -eq 1 ]; then
    echo "$dest/$file"
  else
    echo "$dest/.$file"
  fi
}

file_join() {
  local result=

  for file; do
    if [ "x$file" != "x." ]; then
      if [ "x$result" = "x" ]; then
        result="$file"
      else
        result="$result/$file"
      fi
    fi
  done

  echo "$result"
}

show_dir() {
  local dir=$1
  local dest_dir=$2
  local dotfiles_dir=$3
  local dotfiles_subdir=$4
  local dotted=$5
  local exclude_file_globs="$6"
  local include_file_globs="$7"
  local symlink_dirs_file_globs="$8"
  local dest_path=`build_path "$dest_dir" "$dir" $dotted`

  $DEBUG "show_dir $1 $2 $3 $4 $5 $6 $7 $8"

  $VERBOSE "recurring on $dest_path"

  pushdir "$dir"
  for f in *; do
    $DEBUG "handling the file $f"
    next_dir=`file_join "$dotfiles_subdir" "$dir"`
    handle_file "$f" "$dest_path" "$dotfiles_dir" "$next_dir" 1 "$exclude_file_globs" "$include_file_globs" "$symlink_dirs_file_globs"
  done
  popdir
}

sigil_for() {
  local file=$1
  local symlink_dirs_file_globs=$2
  local copy_always=0
  local symlink_dirs=0

  for copy_file in $COPY_ALWAYS; do
    $DEBUG "copy_file: $copy_file"
    $DEBUG "file: $file"

    case $file in
      $copy_file)
        copy_always=1
        break
        ;;
    esac
  done

  if [ -n "$symlink_dirs_file_globs" ]; then
    symlink_dirs=1
  fi

  if [ $copy_always -eq 1 ]; then
    echo 'X'
  elif [ $symlink_dirs -eq 1 ]; then
    echo '$'
  else
    echo '@'
  fi
}

show_file() {
  local file="$1"
  local dest_dir="$2"
  local dotfiles_dir="$3"
  local dotfiles_subdir="$4"
  local dotted=$5
  local symlink_dirs_file_globs="$6"
  local dest_file=`build_path "$dest_dir" "$file" $dotted`

  if echo $DEST_STACK | grep -vq ":$dest_file"; then
    DEST_STACK="$DEST_STACK:$dest_file"

    src_file=`file_join "$dotfiles_subdir" "$file"`
    abs_src_file=`file_join "$dotfiles_dir" "$src_file"`
    output="$dest_file:$abs_src_file"

    if [ $SHOW_SIGILS -eq 1 ]; then
      sigil=`sigil_for "$src_file" "$symlink_dirs_file_globs"`
      output="$output:$sigil"
    fi

    $PRINT "$output"
  fi
}

handle_file() {
  local file="$1"
  local dest_dir="$2"
  local dotfiles_dir="$3"
  local dotfiles_subdir="$4"
  local dotted=$5
  local exclude_file_globs="$6"
  local include_file_globs="$7"
  local symlink_dirs_file_globs="$8"

  $DEBUG "handle_file $1 $2 $3 $4 $5 $6 $7 $8"

  if [ ! -e "$file" ]; then
    $VERBOSE "skipping non-existent file $file"
  elif is_excluded "$file" "$exclude_file_globs" "$include_file_globs"; then
    $VERBOSE "skipping excluded file $file"
  elif [ -d "$file" ] && is_excluded $file "$symlink_dirs_file_globs"; then
    show_file "$file" "$dest_dir" "$dotfiles_dir" "$dotfiles_subdir" $dotted "$symlink_dirs_file_globs"
  elif [ -d "$file" ]; then
    show_dir "$file" "$dest_dir" "$dotfiles_dir" "$dotfiles_subdir" $dotted "$exclude_file_globs" "$include_file_globs" "$symlink_dirs_file_globs"
  else
    show_file "$file" "$dest_dir" "$dotfiles_dir" "$dotfiles_subdir" $dotted
  fi
}

is_metafile() {
  host_portion=`echo $1 | sed -e 's/host-.*/host-/'`
  tag_portion=`echo $1 | sed -e 's/tag-.*/tag-/'`

  [ x$host_portion = 'xhost-' -o x$tag_portion = 'xtag-' -o "x$1" = "xhooks" ]
}

dotfiles_dir_excludes() {
  local dotfiles_dir="$1"
  local excludes="$2"

  $DEBUG "dotfiles_dir_excludes $dotfiles_dir"
  $DEBUG "  with excludes: $excludes"

  for exclude in $excludes; do
    if echo $exclude | grep -q :; then
      dotfiles_dir_pat=`echo $exclude | sed 's/:.*//'`
      file_glob=`echo $exclude | sed 's/.*://'`

      if [ "x$dotfiles_dir_pat" != "x*" ] && is_relative $dotfiles_dir_pat; then
        dotfiles_dir_pat=$PWD/$dotfiles_dir_pat
      fi

      if [ "x$dotfiles_dir_pat" = "x*" -o "x$dotfiles_dir_pat" = "x$dotfiles_dir" ]; then
        echo $file_glob
      fi
    else
      echo $exclude
    fi
  done
}

is_excluded() {
  local file="$1"
  local exclude_file_globs="$2"
  local include_file_globs="$3"

  $DEBUG "is_excluded $file $exclude_file_globs $include_file_globs"

  for exclude_file_glob in $exclude_file_globs; do
    $DEBUG "file: $file"
    $DEBUG "exclude_file_glob: $exclude_file_glob"

    case "$file" in
      $exclude_file_glob)
        for include_file_glob in $include_file_globs; do
          case "$file" in
            $include_file_glob) return 1;;
          esac
        done

        return 0
        ;;
    esac
  done

  return 1
}

show_help() {
  local exit_code=${1:-0}

  $PRINT "Usage: lsrc [-FVqvh] [-I EXCL_PAT] [-x EXCL_PAT] [-N EXCL_PAT ] [-t TAG] [-d DOT_DIR]"
  $PRINT "see lsrc(1) and rcm(5) for more details"

  exit $exit_code
}

handle_command_line() {
  local arg_tags=
  local verbosity=0
  local version=0
  local show_sigils=0
  local dotfiles_dirs=
  local excludes=
  local includes=
  local symlink_dirs=

  while getopts FVqvhI:x:S:t:d: opt; do
    case "$opt" in
      F) show_sigils=1;;
      h) show_help ;;
      I) includes="$includes $OPTARG";;
      t) arg_tags="$arg_tags $OPTARG";;
      v) verbosity=$(($verbosity + 1));;
      q) verbosity=$(($verbosity - 1));;
      d) dotfiles_dirs="$dotfiles_dirs $OPTARG";;
      V) version=1;;
      x) excludes="$excludes $OPTARG";;
      S) symlink_dirs="$symlink_dirs $OPTARG";;
    esac
  done
  shift $(($OPTIND-1))

  handle_common_flags lsrc $version $verbosity
  SHOW_SIGILS=$show_sigils
  TAGS=${arg_tags:-$TAGS}
  DOTFILES_DIRS=${dotfiles_dirs:-$DOTFILES_DIRS}
  EXCLUDES=${excludes:-$EXCLUDES}
  INCLUDES=${includes:-$INCLUDES}
  SYMLINK_DIRS=${symlink_dirs:-$SYMLINK_DIRS}
  FILES=$@

  $DEBUG "TAGS: $TAGS"
  $DEBUG "DOTFILES_DIRS: $DOTFILES_DIRS"
}

DEST_STACK=

handle_command_line $*

: ${DOTFILES_DIRS:=$DOTFILES_DIRS $DEFAULT_DOTFILES_DIR}
$DEBUG "DOTFILES_DIRS: $DOTFILES_DIRS"

: ${COPY_ALWAYS:=""}
$DEBUG "COPY_ALWAYS: $COPY_ALWAYS"

: ${SYMLINK_DIRS:=""}
$DEBUG "SYMLINK_DIRS: $SYMLINK_DIRS"

for DOTFILES_DIR in $DOTFILES_DIRS; do
  if is_relative $DOTFILES_DIR; then
    DOTFILES_DIR=$PWD/$DOTFILES_DIR
  fi

  if [ ! -d $DOTFILES_DIR ]; then
    $VERBOSE "skipping non-existent directory: $DOTFILES_DIR"
    continue
  fi

  exclude_file_globs=`dotfiles_dir_excludes $DOTFILES_DIR "$EXCLUDES"`
  $DEBUG "exclude_file_globs: $exclude_file_globs"
  include_file_globs=`dotfiles_dir_excludes $DOTFILES_DIR "$INCLUDES"`
  symlink_dirs_file_globs=`dotfiles_dir_excludes $DOTFILES_DIR "$SYMLINK_DIRS"`
  $DEBUG "symlink_dirs_file_globs: $symlink_dirs_file_globs"

  cd $DOTFILES_DIR
  DIR_STACK=":$DOTFILES_DIR"

  for file in ${FILES:-*}; do
    if is_metafile $file; then
      continue
    fi

    handle_file $file $DEST_DIR $DOTFILES_DIR . 0 "$exclude_file_globs" "$include_file_globs" "$symlink_dirs_file_globs"
  done

  cd $DOTFILES_DIR

  host_files=$DOTFILES_DIR/host-$HOSTNAME
  if [ -d $host_files ]; then
    pushdir `basename $host_files`
    for file in ${FILES:-*}; do
      handle_file $file $DEST_DIR $host_files . 0 "$exclude_file_globs" "$include_file_globs"
    done
    popdir
  fi

  cd $DOTFILES_DIR

  for tag in $TAGS; do
    if [ -d tag-$tag ]; then
      pushdir `basename tag-$tag`
      for file in ${FILES:-*}; do
        $DEBUG "TAG: $tag, exclude_file_globs: $exclude_file_globs"
        handle_file $file $DEST_DIR $DOTFILES_DIR/tag-$tag . 0 "$exclude_file_globs" "$include_file_globs"
      done
      popdir
    fi
  done

done