#!/usr/bin/env bash

usage() {
  LESS=-FEXR less <<'HELP'
fv [OPTIONS] [SEARCH]
fuzzy file filtering and command executing

a) allfiles=1 ;;
c) cmd="$OPTARG" ;;
d) dtach=1 ;;
o) loop=1 ;;
s) small=1 ;;

-a    search all dirs and hidden files (possibly quirky)
-c    command to execute [defaults to vim]
-d    run in background (for ie non-terminal programs)
-h    show this help
-l    additional arguments to pass to filtering program
-o    run continuously
-s    run in a smaller window
HELP
}

declare cmd=''
declare cmdopts=()
declare search_str=''
declare search_cmd=''
declare search_opts=()
declare allfiles=''
declare loop
declare small
declare -A colors
colors[red]=$(tput setaf 1)
colors[green]=$(tput setaf 2)
colors[blue]=$(tput setaf 4)
colors[reset]=$(tput sgr0)

color() {
  local c
  c="$1"
  shift
  printf '%s' "${colors[$c]}"
  printf '%s\n' "$@"
  printf '%s' "${colors[reset]}"
}

err() {
  color red "$@" >&2
}

die() {
  [[ -n "$1" ]] && err "$1"
  exit 1
}

has() {
  local o c verbose
  verbose=0
  while getopts 'v' o; do
    case "$o" in
      v) v=1 ;;
    esac
  done
  shift "$((OPTIND-1))"
  for c; do c="${c%% *}"
    if ! command -v "$c" &> /dev/null; then
      (( verbose > 0 )) && err "$c not found"
      return 1
    fi
  done
}

select_from() {
  local o c cmd OPTARG OPTIND
  cmd='command -v'
  while getopts 'c:' o; do
    case "$o" in
      c) cmd="$OPTARG" ;;
    esac
  done
  shift "$((OPTIND-1))"
  for c; do
    if $cmd "${c%% *}" &> /dev/null; then
      echo "$c"
      return 0
    fi
  done
  return 1
}

while getopts 'ac:dhlos' opt; do
  case "$opt" in
    a) allfiles=1 ;;
    c) cmd="$OPTARG" ;;
    d) dtach=1 ;;
    h) usage; exit 0 ;;
    l) search_opts+=( '-l' ) ;;
    o) loop=1 ;;
    s) small=1 ;;
  esac
done
shift "$((OPTIND-1))"

has -v 'fzf' || die

if [[ -v FV_CMD ]]; then
  cmd="$FV_CMD"
elif [[ -z "$cmd" ]]; then
  cmd=$(select_from 'v' 'vim')
fi


if [[ -v FV_SEARCH ]]; then
  search_cmd="$FV_SEARCH"
else
  search_cmd=$(select_from 'ag' 'ack' 'grep')
fi

if [[ "$search_cmd"  == 'grep' ]]; then
  err 'grep is slow, you should strongly consider installing ag or ack'
  sleep .75
fi

if [[ -n "$1" ]]; then
  if [[ -e "$1" ]]; then
    search_opts+=( "$1" )
  else
    search_str="$1"
  fi
  shift
fi

case "$search_cmd" in
  'ag')
    search_opts+=( '--color' )
    if [[ -n "$allfiles" ]]; then
      search_opts+=( '-u' '--hidden' )
    fi
    if [[ "$search_str" == '' ]]; then
      search_opts+=( '-l' )
    fi ;;
  'ack')
    if [[ "$search_str" == '' ]]; then
      if [[ -z "$allfiles" ]]; then
        search_opts+=( '-f' )
      else
        search_opts+=( '-g' '^[^\.]' )
      fi
    else
      search_opts+=( '-l' )
    #   search_opts+=( '--match' )
    fi ;;
  'grep')
    search_opts+=( '-r' '-I' )
    if [[ -z "$allfiles" ]]; then
      if [[ -r ~/.ignore ]]; then
        while read -r line; do
          search_opts+=( "--exclude-dir=$line" )
        done < ~/.ignore
      else
        search_opts+=( '--exclude-dir=bower_components' )
        search_opts+=( '--exclude-dir=node_modules' )
        search_opts+=( '--exclude-dir=jspm_packages' )
        search_opts+=( '--exclude-dir=.cvs' )
        search_opts+=( '--exclude-dir=.git' )
        search_opts+=( '--exclude-dir=.hg' )
        search_opts+=( '--exclude-dir=.svn' )
      fi
    fi
    if [[ -z "$search_str" ]]; then
      search_opts+=( -F '' )
    else
      search_opts+=( -P )
    fi ;;
esac

if [[ "$search_str" != '' ]]; then
  search_opts+=( "$search_str" )
fi

main() {
  local highlight
  highlight=$(select_from  'bat --color=always --style=header' 'highlight -q --force -O ansi')
  choices=$($search_cmd "${search_opts[@]}" 2> /dev/null |
    fzf --ansi --multi --preview="[[ \$(file -ib {}) = *text* ]] && ${highlight} {}") || exit 1

  if [[ "$search_str" != '' ]]; then
    if [[ $search_cmd == 'ag' ]]; then
      choices=$(cut -d: -f1 <<< "$choices")
    fi
  fi

  mapfile -t choices <<< "$choices"

  if [[ $dtach ]]; then
    ($cmd "${cmdopts[@]}" "${choices[@]}" &> /dev/null &)
  else
    $cmd "${cmdopts[@]}" "${choices[@]}"
  fi
}

if [[ -n "$loop" ]]; then
  while main; do
    true
  done
else
  main
fi