treat Ctrl-D at the guess prompt like Enter

Ctrl-D doesn't move the cursor to a new line, but the retry prompts
move up a line assuming Enter was pressed, so each Ctrl-D climbed up
the screen over the keyboard and board. It also quit the game, losing
an offline game to a stray key press.

On a terminal, print the missing newline and carry on as if Enter was
pressed. Only exit when input has really ended (not a terminal), so a
closed pipe still can't spin the retry loop.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

wordle

@@ -33,7 +33,7 @@ function main() {
   declare -g ANSWER
   declare -g POOL='QWERTYUIOPASDFGHJKLZXCVBNM'
   declare -Ag YELLOWS
-  declare -g REVEALING=0
+  declare -Ag KEYS
   ANSWER=$(select_random_word)
 
   set_options "$@"
@@ -51,24 +51,31 @@ function main() {
     init_board
   fi
 
-  [[ "${ONLINE}" == 1 ]] && save_game "NO_EXIT"
+  [[ "${ONLINE}" == 1 ]] && save_game "${ROW}"
 
   render_board
 
   for (( ROW; ROW<HEIGHT; ROW++ )); do
     declare GUESS
     [[ "${KEYBOARD}" == 1 ]] && render_keyboard
-    GUESS=$(retrive_guess)
+    GUESS=$(retrieve_guess) || { echo -en "${NEWLINE}"; exit 0; }
     check_guess "${GUESS}" "${ROW}" ; WIN=$?
 
+    # Save before the reveal so quitting or disconnecting can't undo a guess
+    if [[ $WIN == 5 ]] || (( ROW+1 == HEIGHT )); then
+      save_result
+    elif [[ "${ONLINE}" == 1 ]]; then
+      save_game "$(( ROW+1 ))"
+    fi
+
     reveal_row "${ROW}"
-    REVEALING=0
 
     if [[ $WIN == 5 ]]; then
-      save_result
       echo -e "${CLEAR_DOWN}YOU WIN"
       if [[ "${ONLINE}" == 1 && "${DAILY_DONE}" != 1 ]]; then 
         echo "Share/view your game with -> curl \"${URL_BASE}/${RESULT_FILE}\""
+        echo "Share/view your stats with -> curl \"${URL_BASE}/stats/${USER}\""
+        echo "Check out the new homepage in your browser -> ${URL_BASE}"
         while read -r board_line; do echo "${board_line//[A-Z]/ }"; done < "${RESULT_FILE}"
       fi
       echo "Guess - $(( ROW+1 ))/6"
@@ -76,16 +83,12 @@ function main() {
     fi 
   done
 
-  [[ "${BORDER}" == 1 ]] && echo -en "${CLEAR_DOWN}${INDENT}${INDENT}"
+  render_answer
-  echo -en "${CLEAR_LINE}${BOLD}"
-  for (( i=0; i<WIDTH; i++ )); do
-    echo -en " ${ANSWER:$i:1} "
-  done
-  echo -en "${NEWLINE}${RESET}"
 
-  save_result
+  if [[ "${ONLINE}" == 1 && "${DAILY_DONE}" != 1 ]]; then
-  if [[ "${ONLINE}" == 1 && "${DAILY_DONE}" != 1 ]]; then 
     echo "Share/view your game with -> curl \"${URL_BASE}/${RESULT_FILE}\""
+    echo "Share/view your stats with -> curl \"${URL_BASE}/stats/${USER}\""
+    echo "Check out the new homepage in your browser -> ${URL_BASE}"
     while read -r board_line; do echo "${board_line//[A-Z]/ }"; done < "${RESULT_FILE}"
   fi
   exit 0
@@ -137,9 +140,15 @@ function set_options() {
         echo -en "${CLEAR_SCREEN}"
 
         declare -g USER
-        read -r -p "Username: " USER
+        read -r -p "Username: " USER || exit 1
         USER="${USER,,}"
 
+        # Username is used in file names and URLs so only allow safe characters
+        while [[ -z "${USER}" || "${USER}" == *[!a-z0-9_]* || ${#USER} -gt 32 ]]; do
+          read -r -p "${CLEAR_UP1}Username (letters, numbers and _ only): " USER || exit 1
+          USER="${USER,,}"
+        done
+
         declare -g DAY
         DAY=$(( EPOCHSECONDS / 86400 ))
         
@@ -173,14 +182,15 @@ function set_options() {
           fi
         fi
 
-        trap save_game SIGINT
+        # Progress is saved after every guess so Ctrl-C only needs to tidy the terminal
+        trap 'echo -en "${SHOW_CURSOR}${RESET}"; exit 0' SIGINT
         ;;
       d)
         DELAY=0
         ;;
       h)
         echo -e \
-"Usage: <program_name> [OPTIONS]
+"Usage: wordle [OPTIONS]
 Play a game for Wordle
 
 Options:
@@ -189,6 +199,7 @@ Options:
   -H        Enable hard mode
   -S        Enable strict hard mode (Cannot reuse grey letters)
   -k        disable on screen keyboard
+  -o        Enable online mode
   -d        Enable debug mode (no delay during letter reveal)
   -h        Show this help message and exit"
 
@@ -227,29 +238,54 @@ function render_board() {
   [[ "${BORDER}" == 1 ]] && echo -e "└─────────────────┘"
 }
 
-function retrive_guess() {
+function render_answer() {
+  [[ "${BORDER}" == 1 ]] && echo -en "${CLEAR_DOWN}${INDENT}${INDENT}"
+  echo -en "${CLEAR_LINE}${BOLD}"
+  for (( i=0; i<WIDTH; i++ )); do
+    echo -en " ${ANSWER:$i:1} "
+  done
+  echo -en "${NEWLINE}${RESET}"
+}
+
+# Exits non-zero when input has ended so the caller can quit
+function retrieve_guess() {
   if  [[ -n $1 ]]; then
-    read -r -p "${CLEAR_UP1}$1: " GUESS
+    read -r -p "${CLEAR_UP1}$1: " GUESS || end_of_input
   else
-    read -r -p "${CLEAR_2END}Enter Guess: " GUESS
+    read -r -p "${CLEAR_2END}Enter Guess: " GUESS || end_of_input
   fi
 
   while [[ ${#GUESS} -ne 5 ]] || [[ ! "${GUESS,,}" =~ ^[a-z]{5}$ ]]; do
-    read -r -p "${CLEAR_UP1}Must be 5 letters: " GUESS
+    read -r -p "${CLEAR_UP1}Must be 5 letters: " GUESS || end_of_input
-  done 
+  done
   declare valid_guess
   validate_guess "${GUESS}" ; valid_guess=$?
 
-  [[ ${valid_guess} == 1 ]] && GUESS=$(retrive_guess "Not A Valid Word")
+  declare message
-  [[ ${valid_guess} == 2 ]] && GUESS=$(retrive_guess "Not A Valid Guess")
+  declare -r pos="${HARD_MODE_POS}"
-  [[ ${valid_guess} == 3 ]] && GUESS=$(retrive_guess "GREEN Issue")
+  declare -r letter="${GUESS:pos:1}"
-  [[ ${valid_guess} == 4 ]] && GUESS=$(retrive_guess "YELLOW Issue")
+  declare -ra ordinals=(1st 2nd 3rd 4th 5th)
-  [[ ${valid_guess} == 5 ]] && GUESS=$(retrive_guess "POOL Issue")
+  [[ ${valid_guess} == 1 ]] && message="Not A Valid Word"
-  [[ ${valid_guess} == 6 ]] && GUESS=$(retrive_guess "NEW Issue")
+  [[ ${valid_guess} == 3 ]] && message="${ordinals[pos]} letter must be ${greens[pos]}"
+  [[ ${valid_guess} == 4 ]] && message="Must contain ${yellows[pos]}"
+  [[ ${valid_guess} == 5 ]] && message="${letter^^} is not in the word"
+  [[ ${valid_guess} == 6 ]] && message="${ordinals[pos]} letter can't be ${letter^^}"
+
+  if [[ -n "${message}" ]]; then
+    GUESS=$(retrieve_guess "${message}") || exit 1
+  fi
 
   echo -n "${GUESS^^}"
 }
 
+# Called when read gets Ctrl-D. On a terminal treat it like Enter, but if
+# input has really ended (closed pipe) exit, or the retry loop spins forever
+function end_of_input() {
+  [[ -t 0 ]] || exit 1
+  # Ctrl-D doesn't move to a new line like Enter, which the prompts expect
+  echo -en "${NEWLINE}" >&2
+}
+
 function render_keyboard() {
   declare pos=$(( BORDER*2+7 ))
   echo -en "${RESET}\e[$pos;0H" 
@@ -259,7 +295,12 @@ function render_keyboard() {
     elif [[ $i == 19 ]]; then
       echo -en "${NEWLINE}  "
     fi
-    echo -n "${POOL:$i:1} "
+    declare key="${POOL:$i:1}"
+    if [[ -n "${KEYS[$key]}" ]]; then
+      echo -n "${KEYS[$key]}${BOLD}${LETTER}${key}${RESET} "
+    else
+      echo -n "${key} "
+    fi
   done
   echo -en "${NEWLINE}"
 }
@@ -285,6 +326,8 @@ function hard_mode_check() {
   declare GUESS=$1
 
   for (( i=0; i<WIDTH; i++ )); do
+    HARD_MODE_POS=$i  # letter position that failed, for the error message
+
     if [[ "${STRICT_HARD_MODE}" == 1 ]]; then
       [[ "${POOL}" == *${GUESS:i:1}* ]] || return 5
     fi
@@ -300,7 +343,7 @@ function hard_mode_check() {
     for (( r=ROW-1; r>=0; r-- )); do
       CHAR="${GUESS:i:1}"
       PREV_CHAR="${YELLOWS[$r,$i]}"
-      [[ "${CHAR}" == "${PREV_CHAR}" ]] && return 4
+      [[ "${CHAR}" == "${PREV_CHAR}" ]] && return 6
     done
   done
 
@@ -330,6 +373,7 @@ function check_guess() {
 
     if [[ "${_char}" == "${_answer:$c:1}" ]]; then
       greens[c]="${_char}"
+      KEYS[$_char]="${GREEN}"
       BOARD[$_row,$c]="${GREEN}${BOLD}${LETTER} ${_char} ${UNBOLD}"
       continue
     fi
@@ -338,6 +382,7 @@ function check_guess() {
       chars="${chars/${_char}/}"
       yellows[c]="${_char}"         # volatile - stores previous row yellows
       YELLOWS[$_row,$c]="${_char}"  # stores all yellow from all rounds
+      [[ "${KEYS[$_char]}" != "${GREEN}" ]] && KEYS[$_char]="${YELLOW}"
       BOARD[$_row,$c]="${YELLOW}${BOLD}${LETTER} ${_char} ${UNBOLD}"
     fi
     [[ "${ANSWER}" =~ ${_char} ]] && continue
@@ -350,7 +395,6 @@ function check_guess() {
 }
 
 function reveal_row() {
-  REVEALING=1
   echo -en "${UP1}${SAVE}"
   echo -en "${HIDE_CURSOR}"
   # Must increment by 1 Row as 0 == 1 for escape code
@@ -370,8 +414,9 @@ function load_game() {
   source "${PROGRESS_FILE}"
 }
 
-# shellcheck disable=SC2317  # Don't warn about unreachable commands in this function
+# Takes the row the game should resume from
 function save_game() {
+  declare -r row=$1
   : > "${PROGRESS_FILE}"
 
   for key in "${!BOARD[@]}"; do
@@ -382,36 +427,40 @@ function save_game() {
     echo "YELLOWS[$key]='${YELLOWS[$key]}'" >> "${PROGRESS_FILE}"
   done
 
+  for key in "${!KEYS[@]}"; do
+    echo "KEYS[$key]='${KEYS[$key]}'" >> "${PROGRESS_FILE}"
+  done
+
+  # Previous row's hints, needed by hard_mode_check after a resume
+  for key in "${!greens[@]}"; do
+    echo "greens[$key]='${greens[$key]}'" >> "${PROGRESS_FILE}"
+  done
+
+  for key in "${!yellows[@]}"; do
+    echo "yellows[$key]='${yellows[$key]}'" >> "${PROGRESS_FILE}"
+  done
+
   {
-    echo "ROW=$(( ROW + REVEALING ))"
+    echo "ROW=${row}"
     echo "POOL=${POOL}"
     echo "HARD_MODE=${HARD_MODE}"
     echo "STRICT_HARD_MODE=${STRICT_HARD_MODE}"
     echo "WIN=${WIN}"
     echo "ANSWER=${ANSWER}"
     echo "IN_PROGRESS=1"
-    [[ "${PLAYED}" == 1 ]] && echo 'PLAYED=1' 
+    [[ "${PLAYED}" == 1 ]] && echo 'PLAYED=1'
   } >> "${PROGRESS_FILE}"
-
-  echo -en "${RESET}"
-  [[ -z $1 ]] && exit 0
 }
 
 function save_result() {
   [[ "${ONLINE}" == 0 ]] && return 0
-  [[ "${ONLINE}" == 1 ]] && update_stats
   if [[ "${ONLINE}" == 1 ]] && [[ "${DAILY_DONE}" != 1 ]]; then
+    update_stats
     render_board > "${RESULT_FILE}"
     render_board > "${CUR_RESULT_FILE}"
     if [[ $WIN != 5 ]]; then
-      [[ "${BORDER}" == 1 ]] && echo -en "${CLEAR_DOWN}${INDENT}${INDENT}" >> "${RESULT_FILE}"
+      render_answer >> "${RESULT_FILE}"
-      echo -en "${CLEAR_LINE}${BOLD}" >> "${RESULT_FILE}"
+      render_answer >> "${CUR_RESULT_FILE}"
-      for (( i=0; i<WIDTH; i++ )); do
-        echo -en " ${ANSWER:$i:1} " >> "${RESULT_FILE}"
-        echo -en " ${ANSWER:$i:1} " >> "${CUR_RESULT_FILE}"
-      done
-      echo -en "${NEWLINE}${RESET}" >> "${RESULT_FILE}"
-      echo -en "${NEWLINE}${RESET}" >> "${CUR_RESULT_FILE}"
     fi
   fi
   echo 'PLAYED=1' > "${PROGRESS_FILE}"
@@ -451,6 +500,7 @@ function update_stats() {
     integer_part=$(( result / 100 ))
     decimal_part=$(( result % 100 ))
 
+    [[ ${decimal_part} -lt 10 ]] && decimal_part="0${decimal_part}"
     AVERAGE="${integer_part}.${decimal_part}"
   fi