#!/usr/bin/env bash
#
# Ctlos Linux https://ctlos.github.io
# 
# Dot file management script using zenity, git & rsync
# Written by Nathaniel Maia, November 2017 - March 2018

# Config ~/.dotsrc
# Ignore github ~/.gitignore
# git.io/ctldotsrc
# wget git.io/ctldots
# sudo cp -fv ~/.bin/dots /usr/bin/dots

# immutable values
readonly NAME=$(basename "$0")
readonly CFG="$HOME/.${NAME}rc"

readonly B='\E[1;34m'
readonly R='\E[1;31m'
readonly G='\E[1;32m'
readonly N='\E[0m'
readonly BLD='\E[1m'

readonly WRN="${R}[WARN]${N}:"
readonly INF="${B}[INFO]${N}:"
readonly YN="${B}[${R}y${B}/${R}${BLD}N${N}${B}]${N}: "

readonly MENUTXT="\n  Enter number or letter and press [Enter]. 0/q to cancel\n\n> "

readonly MENU="
\n\t  ${R}1 ${N}| ${R}${BLD}b${N}ackup\t\t-> Backup Files
\t${B}------------------------------------------${N}
\n\t  ${R}2 ${N}| ${R}${BLD}r${N}estore\t\t-> Restore Files
\t${B}------------------------------------------${N}"


main_menu() {
    local choice

    clear
    echo -e "$MENU"
    draw_box 12
    printf "$MENUTXT"
    read -e -r choice
    clear

    [[ $choice =~ (v|V) ]] && V="v"

    case "$choice" in
        0|[Qq]|quit) exit 0 ;;
        1*|[Bb]*|backup*) [[ $BASE_DIR ]] && { backup_files; exit 0; } || edit_config ;;
        2*|[Rr]*|restore*) restore_files && exit 0
    esac

    src_cfg
    main_menu
}

draw_box() {
    local h=${1:-12}            # $1 Box Height
    local w=${2:-57}            # $2 Box Width
    local row=${3:-1}           # $3 Starting Row
    local col=${4:-2}           # $4 Starting Column
    local co=${5:-1}            # $5 Box Color, 1-7
    ((h--))                     # account for corner
    ((w--))                     # account for corner
    local endrow=$((row + h))   # end row
    local endcol=$((col + w))   # end column
    echo -ne "\E[3${co}m"       # foreground colour

    local hz="-" vt="|" cn="+"  # horizontal, vertical, and corner chars

    plot_char() {
        echo -e "\E[${1};${2}H""$3"
    }

    local i=0
    for ((r=row; i<h; r++)); do
        plot_char "$r" "$col" "$vt"    # left side
        ((i++))
    done
    i=0
    for ((r=row; i<h; r++)); do
        plot_char "$r" "$endcol" "$vt" # right side
        ((i++))
    done
    i=0
    for ((c=col; i<w; c++)); do
        plot_char "$row" "$c" "$hz"    # top side
        ((i++))
    done
    i=0
    for ((c=col; i<w; c++)); do
        plot_char "$endrow" "$c" "$hz" # bottom side
        ((i++))
    done

    plot_char "$row" "$col" "$cn"       # left-top corner
    plot_char "$row" "$endcol" "$cn"    # right-top corner
    plot_char "$endrow" "$col" "$cn"    # left-bottom corner
    plot_char "$endrow" "$endcol" "$cn" # right-bottom corner
    tput sgr0  # Reset colours
}

check_reqs() {
    if ! hash git rsync &>/dev/null && hash pacman &>/dev/null; then
        echo -e "\n\n\n\tInstalling:\n\t\tgit\n\t\trsync\n\n\tPlease Wait.."
        draw_box 8
        sleep 1
        clear
        sudo pacman -S git rsync --noconfirm --needed
    fi
}

prep_directory() {
    if [[ $REQ != "True" ]]; then
        check_reqs
        if [[ $BASE_DIR ]]; then    # is set in config but might not exist yet
            if [[ ! -d $BASE_DIR ]]; then  # is not an existing dir

                if [[ $REPO ]] && grep -wq '^https://.*/.*/.*$' <<< "$REPO"; then  # is REPO actually and address
                    git clone "$REPO" "$BASE_DIR"
                else
                    mkdir -p$V "$BASE_DIR" # local backup
                fi
            fi

            [[ -d $BASE_DIR ]] && REQ="True"
        else
            echo -e "$WRN BASE_DIR must be set in config to continue. $EXITING"
        fi
    fi
}

clean_backup_dirs() {
    if [[ ${PREV_BACKUPS[*]} ]] && sub_choice "Perform clean backup (wipe BASE_DIR)" "${R}$BASE_DIR${N}"; then
        for dir in "${PREV_BACKUPS[@]}"; do
            if [[ -d $dir ]] && sub_choice "Wipe all files in /$(basename "$dir")" "${R}$dir${N}"; then
                cd "$dir"
                git rm -r -f .
                # rm -rf$V "$dir"
                [[ $V ]] && sleep 0.5
            fi
        done
    fi
}

commit_changes() {
    if grep -q 'https://' <<< "$REPO"; then
        if sub_choice "Commit and push changes to REPO" "${R}$REPO${N}"; then

            printf "\nEnter commit message below, an example has been provided\n\n> "
            read -e -i "$(date +%Y.%m.%d) Update " -r comment

            if grep -wq '[a-zA-Z0-9]*' <<< "$comment"; then
                cd "$BASE_DIR/" || return 1
                git add .
                git commit -m "$comment"
                git push origin "${BRANCH:-HEAD}"
            else
                echo "Bad commit message"
                sleep 1
                commit_changes
            fi
        fi
    fi
}

backup_files() {
    prep_directory
    clean_backup_dirs

    if [[ ${USER_PATHS[*]} || ${ROOT_PATHS[*]} ]]; then

        echo -e "$INF ${B}Copying files, please wait..$N\n"
        for f in "${USER_PATHS[@]}"; do
            [[ -e $f ]] && rsync -aR$V $f "$BASE_DIR/$USER_DIR/"
            [[ $V ]] && sleep 0.5
        done

        for f in "${ROOT_PATHS[@]}"; do
            [[ -e $f ]] && rsync -aR$V $f "$BASE_DIR/$ROOT_DIR/"
            [[ $V ]] && sleep 0.5
        done

        echo -e "$INF ${G}Backup complete$N"
        sleep 1
    else
        echo -e "$WRN No valid file paths were found.."
        sleep 2
    fi
    commit_changes
}

restore_files() {
    prep_directory
    if [[ ${PREV_BACKUPS[*]} ]]; then
        local msg=""

        for x in "${PREV_BACKUPS[@]}"; do
            if [[ -e $x ]] && sub_choice "Restore everything from /$(basename "$x")" "${R}$x${N}"; then
                if grep -q "$BASE_DIR/$USER_DIR" <<< "$x"; then
                    rsync -avPC --filter="exclude $ROOT_DIR" "$BASE_DIR/$USER_DIR/" "$HOME/"
                elif grep -q "$BASE_DIR/$ROOT_DIR" <<< "$x"; then
                    sudo rsync -avn "$BASE_DIR/$ROOT_DIR/" /
                else
                    echo -e "\n\n\n\t$WRN Unable to restore\n\n\t$x"
                    draw_box 9
                    sleep 1
                fi

            fi

            [[ $V ]] && sleep 0.5
        done

    else
        echo -e "\n\n\n\t$INF ${R}No Existing backups to restore${N}"
        draw_box 9
        sleep 1
    fi
}

mk_cfg() {
    [[ $1 == "new" ]] && edit_config

    for f in "${USER_PATHS[@]}"; do
        if [[ -e $f ]] && ! grep "$f" <<< "$u_paths"; then
            u_paths="$u_paths\"$f\"\n"
        fi
    done

    for f in "${ROOT_PATHS[@]}"; do
        if [[ -e $f ]] && ! grep "$f" <<< "$r_paths"; then
            r_paths="$r_paths\"$f\"\n"
        fi
    done

    local cfg="# config file for dfm (dotfile manager)
\n# repo https address for cloning & pushing (empty for local backup)
REPO=\"$REPO\"
\n# branch, defaults to current branch (HEAD)
BRANCH=\"$BRANCH\"
\n# location where backup folder or repo will be created or cloned
BASE_DIR=\"$BASE_DIR\"
\n# names for storage directories within BASE_DIR.
# created only if needed, stores files from below arrays
USER_DIR=\"${USER_DIR}\"
ROOT_DIR=\"${ROOT_DIR:-root}\"
\n# file paths which will be backed up into the directories above
USER_PATHS=(\n$u_paths)
\nROOT_PATHS=(\n$r_paths)"

    echo -e "$cfg" > "$CFG" && clear
    src_cfg
}

edit_config() {
    $EDITOR "$CFG"
    src_cfg
}

src_cfg() {
    PREV_BACKUPS=()
    ! . "$CFG" 2>/dev/null && mk_cfg "new"
    [[ -d $BASE_DIR/$USER_DIR ]] && PREV_BACKUPS+=("$BASE_DIR/$USER_DIR")
    [[ -d $BASE_DIR/$ROOT_DIR ]] && PREV_BACKUPS+=("$BASE_DIR/$ROOT_DIR")
}

sub_choice() {
    local choice

    clear
    printf "\n\n\n\t$1? $YN\n\n\t$2"
    draw_box 9
    tput cup 3 $((${#1} + 17))
    read -r choice
    clear

    grep -q '[yY]' <<< "$choice" && return 0 || return 1
}

usage() {
    cat <<EOF

USAGE:
       $NAME [OPTIONS..]

OPTIONS:

       -h,--help          Print this usage message
       -v,--verbose       More information output

       Without any options the main dialog menu opens.

INFO:
       Configuration is done in: '$CFG'

       A default config will be created if one is not found,
       followed by opening it in $EDITOR for you to configure.

       Alternatively open your favorite editor and edit it manually.

EOF
    exit 0
}

for arg in "$@"; do
    case $arg in
        -v|--verbose) V="v" ;;
        -h|--help) usage ;;
    esac
done

src_cfg
main_menu

exit 0