#!/bin/sh

#
# update script for ab-openldap container and utility scripts
# version 1.0.0
# script by Asif Bacchus
#

### functions

consoleError() {
    printf "\n%s%s%s\n\n" "$err" "$2" "$norm"
    exit "$1"
}


### text formatting presets
if command -v tput > /dev/null; then
    cyan=$(tput setaf 6)
    err=$(tput bold)$(tput setaf 1)
    norm=$(tput sgr0)
    ok=$(tput setaf 2)
    yellow=$(tput setaf 11)
else
    cyan=''
    err=''
    norm=''
    ok=''
    yellow=''
fi


### pre-requisites

# check if wget is installed
if ! command -v wget > /dev/null 2>&1; then
    consoleError '1' "Sorry, this script requires that 'wget' is installed in order to automatically update files."
fi

# is user root or in the docker group?
if [ ! "$( id -u )" -eq 0 ]; then
    if ! id -Gn | grep docker > /dev/null; then
        consoleError '1' "You must either be root or in the 'docker' group to pull container updates."
    fi
fi

# zero counters
updatesAvailable=0
downloadFailed=0
downloadSuccess=0
updateFailed=0
updateSuccess=0

# reference constants
containerName='ab-openldap'
containerUpdatePath="docker.asifbacchus.app/ldap/$containerName:latest"
serverPath="https://asifbacchus.app/public/$containerName/"
checksumFilename='checksums.sha256'

# files to update
scriptName="$containerName-update.sh"
updateFiles="$containerName-backup.params.template $containerName-backup.sh $containerName.params.template $containerName.sh"

printf "\n%sUpdating %s%s%s:%s\n" "$cyan" "$yellow" "$containerName" "$cyan" "$norm"


### update container

printf "updating container... "
if ! docker pull "$containerUpdatePath" > /dev/null 2>&1; then
    printf "%s[ERROR]\n\n" "$err"
    printf "There was a problem updating the container. Please try again later.%s\n\n" "$norm"
    exit 1
else
    printf "%s[OK]%s\n" "$ok" "$norm"
fi

### checksums
printf "downloading latest checksums... "
if ! wget --quiet --tries=3 --timeout=10 -O "$checksumFilename" "$serverPath$checksumFilename"; then
    printf "%s[ERROR]\n\n" "$err"
    printf "Unable to download updated checksums. Please try again later.%s\n\n" "$norm"
    exit 1
else
    printf "%s[OK]%s\n" "$ok" "$norm"
fi


### script self-update
printf "checking for updates to this script... "
localScriptChecksum=$( sha256sum "./$scriptName" | grep -o '^\S*' )
repoScriptChecksum=$( grep "$scriptName" "$checksumFilename" | grep -o '^\S*' )
if [ "$localScriptChecksum" = "$repoScriptChecksum" ]; then
    printf "[NONE]\n"
else
    # download updated script
    if ! wget --quiet --tries=3 --timeout=10 -O "$scriptName" "$serverPath$scriptName"; then
        printf "%s[ERROR]\n\n" "$err"
        printf "Unable to download script update. Please try again later.%s\n\n" "$norm"
        exit 1
    else
        # verify download
        localScriptChecksum=$( sha256sum "$scriptName" | grep -o '^\S*' )
        if ! [ "$localScriptChecksum" = "$repoScriptChecksum" ]; then
            printf "%s[ERROR]\n\n" "$err"
            printf "Unable to verify checksum of updated script. Please try again later.%s\n\n" "$norm"
        else
        printf "%s[UPDATED]%s\n\n" "$ok" "$norm"
        printf "%s*** This script has been updated. Please re-run it to load the updated version of this file. ***%s\n\n" "$yellow" "$norm"
        exit 0
        fi
    fi
fi

## update files
# remember: do NOT quote dummy var!
set -- dummy $updateFiles
shift
for file; do
    printf "checking '%s' for updates... " "$file"
    repoFileChecksum=$( grep "$file" "$checksumFilename" | grep -o '^\S*' )
    if [ -f "$file" ]; then
        localFileChecksum=$( sha256sum "$file" | grep -o '^\S*' )
    else
        localFileChecksum=0
    fi
    if ! [ "$localFileChecksum" = "$repoFileChecksum" ]; then
        printf "%s[AVAILABLE]%s " "$yellow" "$norm"
        updatesAvailable=$((updatesAvailable+1))
        # download update
        if ! wget --quiet --tries=3 --timeout=10 -O "$file" "$serverPath$file"; then
            printf "%s[ERROR]%s\n" "$err" "$norm"
            downloadFailed=$((downloadFailed+1))
        else
            printf "%s[DOWNLOADED] %s" "$ok" "$norm"
            downloadSuccess=$((downloadSuccess+1))
            # verify download
            localFileChecksum=$( sha256sum "$file" | grep -o '^\S*' )
            if ! [ "$localFileChecksum" = "$repoFileChecksum" ]; then
                printf "%s[INVALID]%s\n" "$err" "$norm"
                updateFailed=$((updateFailed+1))
            else
                printf "%s[VERIFIED]%s\n" "$ok" "$norm"
                updateSuccess=$((updateSuccess+1))
            fi
        fi
    else
        printf "[NONE]\n"
    fi
done


### display results
printf "\n%sResults:%s\n" "$cyan" "$norm"
printf "\tUpdates: %s available\n" "$updatesAvailable"
if [ "$updatesAvailable" -gt '0' ]; then
    if [ "$downloadFailed" -gt '0' ]; then
        printf "\tDownloads: %s successful, %s%s failed%s\n" "$downloadSuccess" "$err" "$downloadFailed" "$norm"
    else
        printf "\tDownloads: %s successful\n" "$downloadSuccess"
    fi
    if [ "$updateFailed" -gt '0' ]; then
        printf "\tUpdates: %s applied, %s%s failed%s\n\n" "$updateSuccess" "$err" "$updateFailed" "$norm"
    else
        printf "\tUpdates: %s applied\n\n" "$updateSuccess"
    fi
fi
exit 0

#EOF