#!/usr/bin/env zsh

# Dotfile manager
#
# By Henrik Lissner <henrik@lissner.net>
# https://github.com/hlissner/dotfiles
#
# Requires: git, zsh

source "${0:A:h}/env"
SEP='.'

# helpers
function echo-debug { echo "$@" | sed -e "s%$HOME%~%g" -e "s%$DOTFILES%.%g"; }
function echo-info  { printf "\r\033[2K\033[0;34m[ .. ]\033[0m %s\n" "$*"; }
function echo-skip  { printf "\r\033[2K\033[38;05;240m[SKIP]\033[0m %s\n" "$*"; }
function echo-ok    { printf "\r\033[2K\033[0;32m[ OK ]\033[0m %s\n" "$*"; }
function echo-fail  { printf "\r\033[2K\033[0;31m[FAIL]\033[0m %s\n" "$*"; }

function _exec { ${DRYRUN:+echo-debug} $@; return ${DRYRUN:+1}; }
function _topic-do {
  if [[ -e "$1/_init" ]]; then
    if [[ ! -x "$1/_init" ]]; then
      echo-fail "$1's init script isn't executable"
      return 1
    fi
    export TOPIC=$1
    pushd -q $1
    _exec ./_init $2
    popd -q
    return $?
  fi
}
function _topics {
  local topics; topics=( "$DOTFILES_DATA"/*.topic(N) )
  echo ${${${topics[@]#$DOTFILES_DATA/}%.topic}/$SEP//}
}


# For _init scripts
function topic-enabled-p { [[ -L "$(topic-path $1)" ]] }
function topic-path { echo "$DOTFILES_DATA/${1/\//$SEP}.topic" }

function mklink {
  if [[ $1 == '-s' ]]; then
    local dosudo=1
    shift
  fi
  local flags="-svf"
  local dest=${@[-1]}
  local srcs; srcs=( ${@:1:-1} )
  if [[ $dest == */ && ! -d $dest ]]; then
    mkdir -p $dest
  elif [[ ! -d ${dest%/*} ]]; then
    mkdir -p ${dest%/*}
  fi
  for lk in ${srcs[@]}; do
    local src
    case $lk in
      /*) src=$lk ;;
      .)  src="$(topic-path $TOPIC)" ;;
      *)  src="$(topic-path $TOPIC)/$lk" ;;
    esac
    if [[ -d $src ]]; then
      if [[ $dest != */ && -d $dest && -L $dest ]]; then
        ${dosudo:+sudo} rm -fv $dest
      fi
    fi
    _exec ${dosudo:+sudo} ln $flags $src $dest
  done
}

function init {
  declare -f $1 >/dev/null || return 1
  echo-info "$TOPIC.init.$1: start"
  $1
  local retval=$?
  echo-ok "$TOPIC.init.$1: done"
  return $retval
}

# deploy functions
function topic-init {
  for topic in $@; do
    if [[ ! -d $topic ]]; then
      echo-fail "$topic doesn't exist!"
      continue
    fi
    echo-ok "$topic"

    local tpath="$DOTFILES/$topic"
    local tsympath="$(topic-path $topic)"
    if [[ -d "$topic/bin" ]]; then
      export path; path=( $tpath/bin $path )
      echo-ok "$topic: added $topic/bin to PATH, temporarily"
    fi

    if [[ -n $LINK ]] || ! topic-enabled-p $topic; then
      local op=install
      mklink $tpath $tsympath
      _topic-do $topic link
    fi

    if [[ -z $INHIBIT_INIT ]]; then
      _topic-do $topic ${FORCE_OP:-${op:-update}}
      if [[ $op == install && $? != 0 ]]; then
        topic-remove $topic
      fi
    fi
  done
}

function topic-remove {
  for topic in $@; do
    if [[ ! -d $topic ]]; then
      echo-fail "$topic doesn't exist"
      continue
    elif ! topic-enabled-p $topic; then
      echo-fail "$topic isn't enabled"
      continue
    fi

    [[ -z $INHIBIT_INIT ]] && _topic-do $topic clean
    _exec rm -f "$(topic-path $topic)" && \
      echo-ok "Removed $topic" || \
      echo-fail "Couldn't remove $topic"
  done
}

function clean {
  local paths; paths=( $XDG_CACHE_HOME $XDG_CONFIG_HOME $XDG_DATA_HOME $XDG_BIN_HOME $DOTFILES_DATA )
  local links; links=( ~/.*(-@DN) ${^paths}/**(-@DN))
  if [[ ${#links[@]} > 1 ]]; then
    echo-info "Removing dead dotfile symlinks..."
    for link in "${links[@]}"; do
      [[ -e $link ]] || _exec rm -fv "$link"
    done
  else
    echo-ok "No dead symlinks in HOME"
  fi

  # Remove empty dotfile folders
  local dirs; dirs=( ${^paths}/**(N/^F) ~/.*(N/^F) )
  if [[ ${#dirs[@]} > 1 ]]; then
    echo-info "Removing empty dotfile directories..."
    for dir in "${dirs[@]}"; do
      _exec rmdir "$dir" && echo-ok "Deleted ${dir/$HOME/~}"
    done
  else
    echo-ok "No empty directories in HOME"
  fi
}


## Bootstrap
if [[ $ZSH_EVAL_CONTEXT != *:file ]]; then
  while getopts acdehlLit opt; do
    case $opt in
      a) TARGETS="$(_topics)"  ;;
      c) CLEAN=1               ;;
      d) REMOVE=1              ;;
      L) LIST=1                ;;
      l) export LINK=1         ;&
      i) export INHIBIT_INIT=1 ;;
      t) export DRYRUN=1       ;;
      h) cat <<EOL
Usage: ${0:A:t} [-acdlLit] [TOPIC...]

  -a   Target all enabled topics (ignores TOPIC args)
  -c   Afterwards, remove dead symlinks & empty dot-directories in $HOME.
       Can be used alone.
  -d   Disable & unlink topic(s)
  -l   Only enable & relink topic(s) (implies -i)
  -L   List enabled topics
  -i   Do not run install/update/clean init scripts
  -t   Do a test run; do not actually do anything
EOL
          exit ;;
      *) >&2 echo-fail "Aborted."
          exit 1 ;;
    esac
  done
  shift $((OPTIND-1))

  if [[ -n $LIST ]]; then
    _topics | tr ' ' $'\n'
  else
    pushd -qL "$DOTFILES"
    if [[ -n $REMOVE ]]; then
      topic-remove ${TARGETS:-$@}
    else
      topic-init ${TARGETS:-$@}
    fi
    [[ -n $CLEAN ]] && clean
    popd -q
  fi
fi

# vim:set ft=sh: