sync-dot-files/sync-dot-files.sh

#!/bin/bash

declare ssh_key
ssh_key="${1:?}"

declare -a accounts
accounts=("${@:2}")
declare me
me="$(whoami)"

function cleanup () {
    popd &>'/dev/null'
}
trap cleanup EXIT

function pprint () {
    printf -- '%s ...\n' "${@}"
}

declare do_force
do_force='false'
for account_index in "${!accounts[@]}"; do
    if [[ "${accounts[${account_index}]}" == '--force' ]] || [[ "${accounts[${account_index}]}" == '-f' ]]; then
        do_force='true'
    fi
    if [[ "${accounts[${account_index}]}" == "${me}" ]]; then unset -v accounts["${account_index}"]; continue; fi
    if ! id "${accounts[${account_index}]}" &>'/dev/null'; then unset -v accounts["${account_index}"]; continue; fi
done

if [[ "${#accounts[@]}" -eq '0' ]]; then
    pprint 'Needs at least second account besides '"'${me}'"', exiting'
    exit 0
fi

declare avail_keys
avail_keys="$(ssh-add -l)"

if ! grep -Piq "${ssh_key}" <<<"${avail_keys}"; then
    pprint 'Key not loaded into agent, exiting'
    exit 0
fi

function is_dirty () {
    git update-index --refresh &>'/dev/null'
    git diff-index --quiet HEAD -- || return 0
    return 1
}

function we_are_ahead () {
    [[ "$(git rev-list origin..HEAD)" ]] && return 0
    return 1
}

function we_are_behind () {
    [[ "$(git rev-list HEAD..origin)" ]] && return 0
    return 1
}

pushd ~ &>'/dev/null'

if is_dirty; then pprint 'Dir '"'$(pwd)'"' is dirty, exiting'; git status; exit 0; fi
if we_are_behind; then pprint 'We are behind remote, exiting'; exit 0; fi

if we_are_ahead || [[ "${do_force}" == 'true' ]]; then
    pprint 'Pushing from '"'${me}'"
    git push
    for account in "${accounts[@]}"; do
        echo
        pprint 'Pulling with '"'${account}'"
        if [[ "${do_force}" == 'true' ]]; then
            sudo --preserve-env=SSH_AUTH_SOCK su --shell /bin/bash --command 'cd; sudo --preserve-env=SSH_AUTH_SOCK git reset --hard' "${account}"
        fi
        sudo --preserve-env=SSH_AUTH_SOCK su --shell /bin/bash --command 'cd; sudo --preserve-env=SSH_AUTH_SOCK git pull; sudo find '"'"'.'"'"' \( -not -user '"${account}"' -or -not -group '"${account}"' \) -print0 | sudo xargs --no-run-if-empty --null -I '"'"'{}'"'"' chown --verbose --no-dereference '"${account}"':'"${account}"' '"'"'{}'"'"'' "${account}"
    done
else
    pprint 'Nothing to do'
fi