#!/bin/sh -e
#
# script to sync repos
# required /etc/reposync.conf
#
# /etc/reposync.conf format:
#  <git url>|<branch>|<local path to sync>
#

log() {
    msg="$1"
    if [ "$LOG" ]; then
		echo "$(date +'%Y-%m-%d %H:%M:%S') $msg" | tee -a "$LOGFILE"
	else
		echo "$msg"
	fi
}

run_cmd() {
    if [ "$DRY_RUN" ]; then
        log " [dry-run] $*"
    else
        log " $*"
        eval "$@"
    fi
}

syncrepo() {
    url=$1
    branch=$2
    path=$3
    
    # if url is empty, do nothing
    if [ ! "$url" ]; then
		exit 0
	fi
    
    # if $path empty, your format is wrong
    if [ ! "$path" ]; then
		echo "/etc/reposync.conf format: <git url>|<branch>|<local path to sync>"
		exit
	fi

    if [ "$FORCE" ]; then
        if [ -d "$path" ]; then
            log "=> Force removing repo directory $path..."
            run_cmd "rm -rf \"$path\""
        fi
    fi

    if [ ! -d "$path/.git" ]; then
        log "=> Sync repo $path..."
        run_cmd "mkdir -p \"$path\""
        run_cmd "git clone --branch \"$branch\" --single-branch \"$url\" \"$path\""
    else
        log "=> Updating repo $path..."
        run_cmd "cd \"$path\" && git fetch origin \"$branch\""
        run_cmd "cd \"$path\" && git reset --hard \"origin/$branch\""
        run_cmd "cd \"$path\" && git clean -fdx"
    fi
}

usage() {
    echo "Usage: $0 [-n|-l|-f]"
    echo " -n  dry-run"
    echo " -l  logging (/var/log/reposync.log)"
    echo " -f  force sync"
    exit 1
}

while [ "$1" ]; do
    case "$1" in
        -n) DRY_RUN=1;;
        -l) LOG=1;;
        -f) FORCE=1;;
        -h) usage;;
    esac
    shift
done

command -v git >/dev/null 2>&1 || {
    echo "error: git is not installed." >&2
    exit 1
}

LOGFILE="/var/log/reposync.log"
CONFFILE="/etc/reposync.conf"

if [ ! -f "$CONFFILE" ]; then
	echo "error: config file not found: $CONFFILE" >&2
	exit 1
fi

grep -Ev '^#|^$' "$CONFFILE" | while IFS='|' read -r url branch path _; do
    syncrepo "$url" "$branch" "$path"
done

exit 0