[shell] Extend powerful cd and move it to its own file

[mina86-dot-files.git] / update

#! /bin/sh

set -eu


##
## Usage
##
usage () {
        cat <<EOF
usage: $0 [ <options> ] [ <files> ]
<options>:
  -f  Update files in current directory from configuration files in home.
  -t  Update configuration files from files in current directory; make backups.
  -T  Like ‘-t’ but don’t make any backups.
  -y  Assume ‘y’ to all questions, i.e. overwrite any changed files w/o asking.
  -n  Assume ‘n’ to all questions, i.e. only copy new files; leave existing be.
EOF
        exit 1
}


##
## Parse arguments
##
direction=
ask=ask

for arg in "$@"; do
        case $arg in
        -)   usage;;
        -?*) :    ;;
        *)   break
        esac
        shift
        while arg=${arg#?}; [ -n "$arg" ]; do
                case "$arg" in
                f*) direction=from   ; backup=false;;
                t*) direction=to     ; backup=true ;;
                T*) direction=to     ; backup=false;;
                y*) ask=if_different ;;
                n*) ask=false        ;;
                *)  usage            ;;
                esac
        done
done


##
## Color handling
##
if ! which tput >/dev/null 2>&1; then
        tput () {
                return 0
        }
fi


##
## Print info
##

case "$direction" in
from)
        tput bold
        tput setaf 7
        echo 'Updating files in current directory from configuration files'
        tput sgr0
        ;;
to)
        tput bold
        tput setaf 7
        echo 'Updating configuration files from files in current directory'
        tput sgr0
        ;;
*)
        usage
esac


##
## File arguments
##
if [ $# -eq 0 ]; then
        match () {
                return 0
        }
else
        match () {
                for f in "$@"; do
                        case "$file" in "$f")
                                return 0
                        esac
                done
                return 1
        }
fi


##
## Interactive asking
##
if diff=$(which cdiff 2>&1); then
        cdiff=$diff
else
        diff=diff
        cdiff=cat
fi

equal() {
        set -- "$@" "$(readlink "$2")" "$(readlink "$3")"

        if [ x"$4" = x"$5" ]; then
                if [ -n "$4" ] || cmp -s "$2" "$3"; then
                        return 0
                fi
        fi

        if [ x"$1" != x-v ]; then
                return 1
        elif [ -z "$4$5" ]; then
                "$diff" -u -- "$3" "$2"
                return 1
        fi

        (
                printf '%s\n' "--- $3"
                printf '%s\n' "+++ $2"

                if [ -z "$5" ]; then
                        sed s/^/-/ <$3
                else
                        printf %s\\n "-→ $5"
                fi

                if [ -z "$4" ]; then
                        sed s/^/+/ <$2
                else
                        printf %s\\n "+→ $4"
                fi
        ) | "$cdiff"
        return 1
}

ask() {
        if equal -v "$1" "$2"; then
                return 1
        fi

        while :; do
                tput bold
                tput setaf 7
                tput setab 4
                printf '%s:' "$2"
                tput sgr0
                tput setaf 7
                tput setab 4
                printf ' [yn] '
                tput sgr0
                read answer || exit 0
                case "$answer" in
                [yY]) return 0 ;;
                [nN]) return 1 ;;
                esac
        done
}

if_different() {
        ! equal -s "$1" "$2"
}


##
## Emacs files handling
##
compile_el() {
        if [ -n "$(which emacs 2>/dev/null)" ]; then
                tput bold
                tput setaf 7
                echo "Compiling $1"
                tput sgr0
                emacs --batch -f batch-byte-compile "$1"
        fi
}


##
## Do the job
##
handle() {
        case $3 in *@) set -- "$1" "$2" "${3%@}${2##*/}"; esac

        case $1 in from)
                [ -d "${3%/*}" ] || return 0
                set -- "$1" "$3" "$2"
        esac

        if [ -h "$3" ] || [ -e "$3" ]; then
                if ! $ask "$2" "$3" <&3; then
                        return 0
                elif $backup; then
                        mv -- "$3" "$3~"
                fi
        fi

        case $3 in */*)
                mkdir -p -- "${3%/*}"
        esac
        cp -dv -- "$2" "$3"

        case "$direction:$3" in to:*.el)
                compile_el "$3"
        esac
}

while read pattern destination; do
        for file in $pattern; do
                case "$file" in *\~|*/\#*|*\#|*/.*)
                        continue
                esac
                if ! match "$@"; then
                        :
                elif [ -h "$file" ] || [ -f "$file" ]; then
                        handle "$direction" "$file" "$HOME/$destination"
                elif ! [ -e "$file" ]; then
                        echo "update: $file: missing, skipping" >&2
                fi
        done
done 3<&1 <<EOF
aspell.en.pws      .@
bin/*              .local/bin/@
emacs/*            .config/emacs/@
git/*              .config/git/@
inputrc            .@
irssi.theme        .irssi/mina.theme
libexec/*          .local/libexec/@
mail/*             .mail/@
mpv/*              .config/mpv/@
sawfishrc          .sawfish/rc
sh/*               .@
statuses           .irssi/@
x/80-char.png      .urxvt/@
x/Xresources       .config/@
x/gtk-3.0.ini      .config/gtk-3.0/settings.ini
x/gtkrc-2.0        .@
x/local.keymap     .config/xkb/keymap/local
x/local.symbols    .config/xkb/symbols/local
x/xinitrc          .@
x/xserverrc        .@
x/xsettingsd       .@
EOF