インタラクティブな選択メニュー

select-min.sh

#!/usr/bin/env bash

CaptureSpecialKeys(){
    local SELECTION rest

    IFS= read -r -n1 -s SELECTION
    #echo "$SELECTION" | hexdump >&2
    if [[ $SELECTION == $'\x1b' ]]; then
        read -r -n2 -s rest
        SELECTION+="$rest"
    else
        if [[ "$SELECTION" == '' ]] ;then
            echo "Enter"
            return 0
        else
            read -r rest
            echo "$SELECTION$rest"
            return 0
        fi
    fi

    case $SELECTION in
        $'\x1b\x5b\x41') #up arrow
            echo "Up"
            ;;
        $'\x1b\x5b\x42') #down arrow
            echo "Down"
            ;;
        $'\x1b\x5b\x43') #right arrow
            echo "Right"
            ;;
        $'\x1b\x5b\x44') #left arrow
            echo "Left"
            ;;
        $'\x20') #space
            echo "Space"
            ;;
    esac
}

ClearLine(){ printf "\033[2K"; }
MoveCursorUp(){ printf "\033[%dA" "$1"; }
ResetStyle(){ printf "\033[0m"; }
ClearUpperLines(){
    # shellcheck disable=SC2034
    for i in $(seq 1 "$1"); do
        MoveCursorUp 1
        ClearLine
    done
}

TextUnderLine(){ printf "\033[4m" ; }
TextBold(){ printf "\033[1m" ; }

#----- ここから処理 -----
Choices=(HOGE FUGA PIYO)
CurrentChoice=0
Key=""

ShowMenu(){
    for i in "${!Choices[@]}"; do
        if [[ "$i" = "$CurrentChoice" ]]; then
            TextUnderLine
            TextBold
            echo " * $i: ${Choices[$i]}"
        else
            echo "   $i: ${Choices[$i]}"
        fi
        ResetStyle
    done
}

UpdateMenuScreen(){
    ClearUpperLines "${#Choices[@]}"
    ShowMenu
}

ShowMenu

while [[ "$Key" != "Enter" ]]; do
    Key="$(CaptureSpecialKeys)"
    case "$Key" in
        Up)
            if (( "$CurrentChoice" != 0 )); then
                CurrentChoice=$((CurrentChoice - 1))
                UpdateMenuScreen
            fi
            ;;
        Down)
            if (( "$CurrentChoice" != "${#Choices[@]}" - 1 )); then
                CurrentChoice=$((CurrentChoice + 1))
                UpdateMenuScreen
            fi
            ;;
    esac
done 

echo "選択されたのは${Choices[$CurrentChoice]}です"

select-original.sh

#!/usr/bin/env bash

Choices=(HOGE FUGA PIYO)

ClearScreen(){
    printf "\033[2J"
}
ClearRight(){
    printf "\033[0K"
}
ClearLeft(){
    printf "\033[1K"
}
ClearLine(){
    printf "\033[2K"
}
MoveCursor(){
    printf "\033[%d;%dH" "$1" "$2"
}
MoveCursorUp(){
    printf "\033[%dA" "$1"
}
MoveCursorDown(){
    printf "\033[%dB" "$1"
}
MoveCursorRight(){
    printf "\033[%dC" "$1"
}
MoveCursorLeft(){
    printf "\033[%dD" "$1"
}
SaveCursor(){
    printf "\033[s"
}
ResetStyle(){
    printf "\033[0m"
}

CurrentChoice=0


ShowMenu(){
    for i in "${!Choices[@]}"; do
        if [ $i -eq $CurrentChoice ]; then
            printf "\033[7m"
        fi
        echo "  $i: ${Choices[$i]}"
        ResetStyle
    done
}

UpdateMenuScreen(){
    MoveCursorUp 1
    ClearLine
    for i in "${!Choices[@]}"; do
        MoveCursorUp 1
        ClearLine
    done

    ShowMenu
}
ShowMenu

while IFS= read -r -n1 -s SELECTION && [[ -n "$SELECTION" ]]; do
    if [[ $SELECTION == $'\x1b' ]]; then
        read -r -n2 -s rest
        SELECTION+="$rest"
    fi	

    case $SELECTION in
        $'\x1b\x5b\x41') #up arrow
            echo "上"
            if [ $CurrentChoice -gt 0 ]; then
                CurrentChoice=$((CurrentChoice-1))
            fi
            UpdateMenuScreen
            ;;
        $'\x1b\x5b\x42') #down arrow
            echo "下"
            if [ $CurrentChoice -lt $((${#Choices[@]}-1)) ]; then
                CurrentChoice=$((CurrentChoice+1))
            fi
            UpdateMenuScreen
            ;;
        $'\x1b\x5b\x43') #right arrow
            echo "右"
            ;;
        $'\x1b\x5b\x44') #left arrow
            echo "左"
            ;;
        $'\x20') #space
            echo "スペース"
            ;;
    esac
done

echo "選択されたのは${Choices[$CurrentChoice]}です"

select.sh

#!/usr/bin/env bash

CaptureSpecialKeys(){
    local SELECTION rest

    IFS= read -r -n1 -s SELECTION
    #echo "$SELECTION" | hexdump >&2
    if [[ $SELECTION == $'\x1b' ]]; then
        read -r -n2 -s rest
        SELECTION+="$rest"
    else
        if [[ "$SELECTION" == '' ]] ;then
            echo "Enter"
            return 0
        else
            read -r rest
            echo "$SELECTION$rest"
            return 0
        fi
    fi


    case $SELECTION in
        $'\x1b\x5b\x41') #up arrow
            echo "Up"
            ;;
        $'\x1b\x5b\x42') #down arrow
            echo "Down"
            ;;
        $'\x1b\x5b\x43') #right arrow
            echo "Right"
            ;;
        $'\x1b\x5b\x44') #left arrow
            echo "Left"
            ;;
        $'\x20') #space
            echo "Space"
            ;;
    esac
}
ClearScreen(){
    printf "\033[2J"
}
ClearRight(){
    printf "\033[0K"
}
ClearLeft(){
    printf "\033[1K"
}
ClearLine(){
    printf "\033[2K"
}
MoveCursor(){
    printf "\033[%d;%dH" "$1" "$2"
}
MoveCursorUp(){
    printf "\033[%dA" "$1"
}
MoveCursorDown(){
    printf "\033[%dB" "$1"
}
MoveCursorRight(){
    printf "\033[%dC" "$1"
}
MoveCursorLeft(){
    printf "\033[%dD" "$1"
}
SaveCursor(){
    printf "\033[s"
}
ResetStyle(){
    printf "\033[0m"
}
ClearUpperLines(){
    # shellcheck disable=SC2034
    for i in $(seq 1 "$1"); do
        MoveCursorUp 1
        ClearLine
    done
}



#----- ここから処理 -----
Choices=(HOGE FUGA PIYO)
CurrentChoice=0
Key=""

ShowMenu(){
    for i in "${!Choices[@]}"; do
        if [[ "$i" = "$CurrentChoice" ]]; then
            echo " * $i: ${Choices[$i]}"
        else
            echo "   $i: ${Choices[$i]}"
        fi
    done
}

UpdateMenuScreen(){
    ClearUpperLines "${#Choices[@]}"
    ShowMenu
}


ShowMenu

while [[ -z "$Key" ]]; do
    Key="$(CaptureSpecialKeys)"
    case "$Key" in
        Up)
            if (( "$CurrentChoice" != 0 )); then
                CurrentChoice=$((CurrentChoice - 1))
                UpdateMenuScreen
            fi
            ;;
        Down)
            if (( "$CurrentChoice" != "${#Choices[@]}" - 1 )); then
                CurrentChoice=$((CurrentChoice + 1))
                UpdateMenuScreen
            fi
            ;;
        Enter)
            break
            ;;
    esac
    Key=""
done 

echo "選択されたのは${Choices[$CurrentChoice]}です"