#!/bin/bash -l

set -eE -o pipefail
trap 'echo "$0:$LINENO:error: \"$BASH_COMMAND\" returned $?"' ERR


sysv() {
    e "$@"
    "$@"
}


shopt -s nullglob

# if we make a link back to the root, traversing the subdirs stops.
# This makes it so we can do subdir directories. Must call with absolute
# paths.

subdir-link-r() {
    local root="$1"
    local targets=()
    if [[ $2 ]]; then
        targets=( "$2"/* )
    else
        for f in "$1"/*; do
            [[ -d $f ]] && targets+=("$f") ||:
        done
    fi
    local below="$( readlink -f "$root/..")"
    for path in "${targets[@]}"; do
        local fullpath="$(readlink -f "$path")"
        #e $fullpath $below # debug
        if [[ -f $path || $(dirname $(readlink -f "$fullpath")) == "$below" ]]; then
            if [[ $dir == /p/* ]]; then
                homes=(/home/ian)
            else
                homes=(/home/*)
            fi
            for user in ${homes[@]}; do
                sysv lnf -T "$path" "$user/${path#$root/}"
            done
        elif [[ -d "$path" ]]; then
            subdir-link-r "$root" "$path"
        fi
    done
}

common-file-setup() {
    if [[ -e $1/subdir_files ]]; then
        subdir-link-r $1/subdir_files
    fi
    local x=( $1/!(subdir_files|filesystem) )
    (( ${#x[@]} >= 1 )) || return 0
    sysv lnf ${x[@]} ~
    # as of this writing, it doesn't exist in /a/c, but I've used it in the past.
    if [[ -e $1/filesystem ]]; then
        sysv s cp -R $1/filesystem/* /
    fi
}

# p needs to go first so .ssh link is created, then config link inside it
for dir in {/a/c,/p/c}{,/machine_specific/$HOSTNAME}; do
    common-file-setup $dir
done