#! /usr/bin/env bash
#
# RTC Chess - chess-via-nex
# Author: samhunter@rawtext.club
#
#
REPLAY=""

readonly SECRET="$(cat nightfall-city.id)"
declare -A CB

nex_connect() {
  cmd=$1
  shift
  GAMEURL="$1"
  shift
  case "$cmd" in
    "get")
      printf "%s\r\n" "$GAMEURL" | nc nightfall.city 1900
      #tail -1 "$GAMEURL"
      ;;
    "put")
      printf "%s\n%s\n%s\n.\n" "$GAMEURL" "$SECRET" "$*" | nc nightfall.city 1915
      #printf "%s\n" "$*" > "$GAMEURL"
      ;;
    *) printf "incorrect command %s (parameters: %s)\n" "$cmd" "$@"
      ;;
  esac
}

instructions () {
  printf "chess - chess-over-nex game.\n"
  printf "%s [-b|-w] [-f]] [-l] [-h] [your url] [their url]\n" $(basename $0)
  printf "\t-b|-w - black side/white side perspective\n"
  printf "\t-f    - fancy Unicode characters (might not work on some terminals.\n"
  printf "\t-h    - this help\n"
  printf "\nSpecify your and your opponent's URL as the last two parameters.\n"
  printf "\nInstructions\n"
  printf "Move:\n\tspecify the start and end positions,\n\teg. e2e4, press Enter\n"
  printf "Check:\n\tadd '+' to the move, eg. e2e4+\n"
  printf "Checkmate:\n\tadd '#' to the move, eg. e2e4#\n"
  printf "Surrender:\n\tadd 's' to the move, eg. e2e4s\n"
  printf "Castling:\n\tking-side: oo\n\tqueen-side: ooo\n"
  printf "\nAll moves can use optional dashes eg. e2-e4\n"
  printf  "\n"
  printf "Quit:\n\tEmpty line or Q, followed by Enter\n"
  exit 0
}

declare -Ar fancy=(
  [wp]="$(printf "\u2659")"
  [wr]="$(printf "\u2656")"
  [wn]="$(printf "\u2658")"
  [wb]="$(printf "\u2657")"
  [wq]="$(printf "\u2655")"
  [wk]="$(printf "\u2654")"
  [xx]=" "
  [bp]="$(printf "\u265F")"
  [br]="$(printf "\u265C")"
  [bn]="$(printf "\u265E")"
  [bb]="$(printf "\u265D")"
  [bq]="$(printf "\u265B")"
  [bk]="$(printf "\u265A")"
)

declare -Ar plain=(
  [wp]="p"
  [wr]="r"
  [wn]="n"
  [wb]="b"
  [wq]="q"
  [wk]="k"
  [xx]=" "
  [bp]="P"
  [br]="R"
  [bn]="N"
  [bb]="B"
  [bq]="Q"
  [bk]="K"
)

setup_board() {
  case $1 in
    ("f"|"fancy")
      # I'm using a dark background, hence the reversed colours of pieces
      wp=${fancy[wp]}; wr=${fancy[wr]}; wn=${fancy[wn]}; wb=${fancy[wb]}; wq=${fancy[wq]}; wk=${fancy[wk]}
      bp=${fancy[bp]}; br=${fancy[br]}; bn=${fancy[bn]}; bb=${fancy[bb]}; bq=${fancy[bq]}; bk=${fancy[bk]}
      xx=${fancy[xx]};
      ;;
   (*)
      wp=${plain[wp]}; wr=${plain[wr]}; wn=${plain[wn]}; wb=${plain[wb]}; wq=${plain[wq]}; wk=${plain[wk]}
      bp=${plain[bp]}; br=${plain[br]}; bn=${plain[bn]}; bb=${plain[bb]}; bq=${plain[bq]}; bk=${plain[bk]}
      xx=${plain[xx]}
      ;;
  esac
  CB["a8"]=$wr; CB["b8"]=$wn; CB["c8"]=$wb; CB["d8"]=$wq; CB["e8"]=$wk; CB["f8"]=$wb; CB["g8"]=$wn; CB["h8"]=$wr
  CB["a7"]=$wp; CB["b7"]=$wp; CB["c7"]=$wp; CB["d7"]=$wp; CB["e7"]=$wp; CB["f7"]=$wp; CB["g7"]=$wp; CB["h7"]=$wp
  CB["a6"]=$xx; CB["b6"]=$xx; CB["c6"]=$xx; CB["d6"]=$xx; CB["e6"]=$xx; CB["f6"]=$xx; CB["g6"]=$xx; CB["h6"]=$xx
  CB["a5"]=$xx; CB["b5"]=$xx; CB["c5"]=$xx; CB["d5"]=$xx; CB["e5"]=$xx; CB["f5"]=$xx; CB["g5"]=$xx; CB["h5"]=$xx
  CB["a4"]=$xx; CB["b4"]=$xx; CB["c4"]=$xx; CB["d4"]=$xx; CB["e4"]=$xx; CB["f4"]=$xx; CB["g4"]=$xx; CB["h4"]=$xx
  CB["a3"]=$xx; CB["b3"]=$xx; CB["c3"]=$xx; CB["d3"]=$xx; CB["e3"]=$xx; CB["f3"]=$xx; CB["g3"]=$xx; CB["h3"]=$xx
  CB["a2"]=$bp; CB["b2"]=$bp; CB["c2"]=$bp; CB["d2"]=$bp; CB["e2"]=$bp; CB["f2"]=$bp; CB["g2"]=$bp; CB["h2"]=$bp
  CB["a1"]=$br; CB["b1"]=$bn; CB["c1"]=$bb; CB["d1"]=$bq; CB["e1"]=$bk; CB["f1"]=$bb; CB["g1"]=$bn; CB["h1"]=$br
}

miniboard() {
  for r in {8..1}; do
    x=r
    printf "%1s " "$r"
    for c in {a..h}; do
      if (( ++x % 2 == 0 )); then
        printf " %1s "  ${CB[$c$r]}
      else
        printf "\x1b[7;1m %1s \x1b[0m"  ${CB[$c$r]}
      fi
    done
    printf "\n"
  done
  printf "  "
  for c in {a..h}; do
    printf " %1c " $c
  done
  printf "\n"
}

flipped_board() {
  printf "\n  +---+---+---+---+---+---+---+---+\n"
  for r in {1..8} ; do
    printf "%2s" $r
    for c in {h..a} ;do
      printf "| %1s " "${CB[$c$r]}"
    done
    printf "|\n  +---+---+---+---+---+---+---+---+\n"
  done
  printf "  "
  printf "  %1s " {h..a}
  printf "\n"
}

board() {
  printf "\n  +---+---+---+---+---+---+---+---+\n"
  for r in {8..1} ; do
    printf "%2s" $r
    for c in {a..h} ;do
      printf "| %1s " "${CB[$c$r]}"
    done
    printf "|\n  +---+---+---+---+---+---+---+---+\n"
  done
  printf "  "
  printf "  %1s " {a..h}
  printf "\n"
}

move() {
  MOVE=${1,,}
  ACTION=""
  HIT=""
  # en passant?
  if [[ "${MOVE,,}" =~ (a[45]-?b[36]|h[45]-?g[36]|b[45]-?[ac][36]|c[45]-?[db][36]|d[45]-?[ce][36]|e[45]-?[df][36]|f[45]-?[eg][36]|g[45]-?[fh][36]) ]] ; then
    if [[ "$MOVE" =~ (([a-h])([1-8]))-?(([a-h])([1-8])) ]]; then
    # printf "%s\n" "${BASH_REMATCH[@]}"
    # sleep 20
      FM=${BASH_REMATCH[1]}
      TO=${BASH_REMATCH[4]}
      EP="${BASH_REMATCH[5]}${BASH_REMATCH[3]}"
      PIECE="${CB[$FM]}"
      HITP="${CB[$EP]}"
      if [[ "$PIECE" == "p" && "$HITP" == "P" ]] ||  [[ "$PIECE" == "P" && "$HITP" == "p" ]] ; then
        HIT="$HITP"
        CB[$EP]=" "
        CB[$TO]="$PIECE"
      fi
    fi
  fi

  if [[ "$MOVE" =~ ([a-h][1-8])-*([a-h][1-8])-?(.*) ]] ; then
    FM="${BASH_REMATCH[1]}"
    TO="${BASH_REMATCH[2]}"
    ACTION="${BASH_REMATCH[3]}"
    case $ACTION in
      ("m"|"M"|"#"|"++")
        MSG="Checkmate"   # Checkmate
        ACTION="#"
        ;;
      ("c"|"C"|"+") MSG="Check"        # Check
        ACTION="+"
        ;;
      ("s"|"S") MSG="You won! GG" # Surrender
        ACTION="S"
        ;;
      *) MSG=""
        ;;
    esac
    PIECE="${CB[$FM]}"
    CB[$FM]=" "
    # Promotion
    if [[ "$PIECE" =~ p && "$TO" =~ [a-h]1 ]]; then
      PIECE="q"
    elif [[ "$PIECE" =~ P && "$TO" =~ [a-h]8 ]]; then
      PIECE="Q"
    fi
    CB[$TO]="$PIECE"
  elif [[ "$MOVE" =~ o-?o-?o ]]; then
    FM=$MOVE
    TO=""
    MSG="castling queen-side"
    if [ $WHITES_MOVE -eq 1 ]; then
      CB["c1"]="${CB["e1"]}"
      CB["e1"]=" "
      CB["d1"]="${CB["a1"]}"
      CB["a1"]=" "
    else
      CB["c8"]="${CB["e8"]}"
      CB["e8"]=" "
      CB["d8"]="${CB["a8"]}"
      CB["a8"]=" "
    fi
  elif [[ "$MOVE" =~ o-?o ]]; then
    FM=$MOVE
    TO=""
    MSG="castling king-side"
    if [ $WHITES_MOVE -eq 1 ]; then
      CB["g1"]="${CB["e1"]}"
      CB["e1"]=" "
      CB["f1"]="${CB["h1"]}"
      CB["h1"]=" "
    else
      CB["g8"]="${CB["e8"]}"
      CB["e8"]=" "
      CB["f8"]="${CB["h8"]}"
      CB["h8"]=" "
    fi
  fi
  [[ -z "$ACTION" && -n "$HIT" ]] && ACTION="x"
  LAST_MOVE="you: $FM$TO$ACTION $MSG"
}

init () {
  printf "Loading game status...\n"
  MOVES=( $(nex_connect get "$GAMEURLIN" |sed -e 's/:/ /g'))
  WHITES_MOVE=1
  for MOVE in "${MOVES[@]:1}"; do
    move $MOVE
    WHITES_MOVE=$((1-$WHITES_MOVE))
  done
  LAST_MOVE="$FM$TO$ACTION $MSG"
}

#trap clean_exit INT QUIT TERM EXIT

FANCY=false
BLACK_VIEW=false
while getopts :bBhflwW FLAG; do
  case $FLAG in
    (f) FANCY=true
      ;;
    (b|B) BLACK_VIEW=true
      ;;
    (w|W) BLACK_VIEW=false
      ;;
    (h) instructions ; exit 0
      ;;
    (*) printf "%s [-b|-w] [-f]] [-h] [game id]\n" $(basename $0); exit 0
      ;;
  esac
done
shift $((OPTIND - 1))

GAMEURLIN="$1"
GAMEURLOUT="$2"


MSG=""
if $FANCY ; then
  setup_board fancy
else
  setup_board normal
fi
init
#clear

if $BLACK_VIEW ; then
  flipped_board
else
  board
fi


echo "Last move: $LAST_MOVE"
read -p "Your move [? for help]: " MOVE
if [[ -n "$MOVE" ]]; then
  [[ "$MOVE" == "?" ]] && { instructions ; exit ; }
  [[ "$MOVE" == "Q" ]] && exit
  move $MOVE
  #clear
  if $BLACK_VIEW ; then
    flipped_board
  else
    board
  fi
  echo "Last move: $LAST_MOVE"
  read -p "Send your move [y/n]? " SEND
  if [[ "$SEND" == "y" ]]; then
    SEND_MOVE="${MOVES[@]:1} $MOVE"
    nex_connect put "$GAMEURLOUT" "$(printf 'MOVE:%s' "${SEND_MOVE## }")"
  else
    echo "Your move wasn't sent."
  fi
fi