Data commit

Task/15-puzzle-game/UNIX-Shell/15-puzzle-game.sh

@@ -0,0 +1,97 @@
+#!/usr/bin/env bash
+main() {
+  local puzzle=({1..15} " ") blank moves_kv i key count total last
+  printf '\n'
+  show_puzzle "${puzzle[@]}"
+  printf '\nPress return to scramble.'
+  read _
+  IFS= readarray -t puzzle < <(scramble "${puzzle[@]}")
+  printf '\r\e[A\e[A\e[A\e[A\e[A\e[A'
+  show_puzzle "${puzzle[@]}"
+  printf '\nUse hjkl to slide tiles. '
+  printf '\r\e[A\e[A\e[A\e[A\e[A'
+  total=0
+  while ! solved "${puzzle[@]}"; do
+    show_puzzle "${puzzle[@]}"
+    { read blank; readarray -t moves_kv; } < <(find_moves "${puzzle[@]}")
+    local count=${#moves_kv[@]}/2
+    local -A moves
+    for (( i=0; i<count; i++ )); do
+      moves[${moves_kv[i]}]=${moves_kv[i+count]}
+    done
+    read -r -n 1 key
+    printf '\r '
+    if [[ "$key" = u ]]; then
+      (( total -= 2 ))
+      case "$last" in
+        h) key=l;;
+        j) key=k;;
+        k) key=j;;
+        l) key=h;;
+      esac
+    fi
+    if [[ -n "${moves[$key]}" ]]; then
+      last=$key
+      (( total++ ))
+      i=${moves[$key]}
+      puzzle[$blank]=${puzzle[i]}
+      puzzle[i]=' '
+    fi
+    printf '\r\e[A\e[A\e[A\e[A'
+  done
+  show_puzzle "${puzzle[@]}"
+  printf '\nSolved in %d moves.     \n' "$total"
+}
+
+
+solved() {
+  local solved=({1..15} ' ')
+  [[ "${puzzle[*]}" == "${solved[*]}" ]]
+}
+
+show_puzzle() {
+  printf '%2s %2s %2s %2s\n' "$@"
+}
+
+find_moves() {
+  local puzzle=("$@")
+  local i j blank
+  for (( i=0; i<${#puzzle[@]}; ++i )); do
+    if [[ "${puzzle[i]}" == " " ]]; then
+      blank=$i
+      break
+    fi
+  done
+  local -A moves=()
+  if (( blank%4 )); then
+    # swapping blank with tile to its left
+    # is sliding that tile right, which is the l key
+    moves['l']=$(( blank-1 ))
+  fi
+  if (( blank%4 != 3 )); then
+    moves['h']=$(( blank+1 )) # left
+  fi
+  if (( blank >= 4 )); then
+    moves['j']=$(( blank-4 )) # down
+  fi
+  if (( blank < 12 )); then
+    moves['k']=$(( blank+4 )) # up
+  fi
+  printf '%s\n' "$blank" "${!moves[@]}" "${moves[@]}"
+}
+
+scramble() {
+  local puzzle=("$@") i j
+  for (( i=0; i<256; ++i )); do
+    local blank moves
+    { read blank; readarray -t moves; } < <(find_moves "${puzzle[@]}")
+    moves=(${moves[@]:${#moves[@]}/2})
+    local dir=$(( RANDOM % ${#moves[@]} ))
+    j=${moves[dir]}
+    puzzle[blank]=${puzzle[j]}
+    puzzle[j]=' '
+  done
+  printf '%s\n' "${puzzle[@]}"
+}
+
+main "$@"