#!/bin/bash

# Functions
get_start_time(){
    START_TIME=$(date +%s)
    CURRENT_DATE=$(date --date @"$START_TIME" +"%Y%m%d_%H%M%S")
}
get_expiration_time() {
    END_TIME=$(date +%s)
    END_DATE_READABLE=$(date --date @"$END_TIME" +"%d.%m.%Y - %H:%M:%S")
    DURATION=$((END_TIME-START_TIME))
    DURATION_SEC=$((DURATION % 60))
    DURATION_MIN=$(((DURATION / 60) % 60))
    DURATION_HOUR=$((DURATION / 3600))
    DURATION_READABLE=$(printf "%02d hours %02d minutes %02d seconds" $DURATION_HOUR $DURATION_MIN $DURATION_SEC)
}

# Test if all volumes aren't empty
VOLUME_DIRS="$(find /nextcloud_aio_volumes -mindepth 1 -maxdepth 1 -type d)"
mapfile -t VOLUME_DIRS <<< "$VOLUME_DIRS"
for directory in "${VOLUME_DIRS[@]}"; do
    if ! mountpoint -q "$directory"; then
        echo "$directory is not a mountpoint which is not allowed."
        exit 1
    fi
done

# Check if target is mountpoint
if ! mountpoint -q /mnt/borgbackup; then
    echo "/mnt/borgbackup is not a mountpoint which is not allowed"
    exit 1
fi

# Check if target is empty
if [ "$BORG_MODE" != backup ] && [ "$BORG_MODE" != test ] && ! [ -f "$BORG_BACKUP_DIRECTORY/config" ]; then
    echo "The repository is empty. cannot perform check or restore."
    exit 1
fi

# Do not continue if this file exists (needed for simple external blocking)
if [ -f "$BORG_BACKUP_DIRECTORY/aio-lockfile" ]; then
    echo "Not continuing because aio-lockfile exists - it seems like a script is externally running which is locking the backup archive."
    echo "If this should not be the case, you can fix this by deleting the 'aio-lockfile' file from the backup archive directory."
    exit 1
fi

# Create lockfile
if [ "$BORG_MODE" = backup ] || [ "$BORG_MODE" = restore ]; then
    touch "/nextcloud_aio_volumes/nextcloud_aio_database_dump/backup-is-running"
fi

# Do the backup
if [ "$BORG_MODE" = backup ]; then

    # Test if important files are present
    if ! [ -f "/nextcloud_aio_volumes/nextcloud_aio_mastercontainer/data/configuration.json" ]; then
        echo "configuration.json not present. Cannot perform the backup!"
        exit 1
    elif ! [ -f "/nextcloud_aio_volumes/nextcloud_aio_nextcloud/config/config.php" ]; then
        echo "config.php is missing cannot perform backup"
        exit 1
    elif ! [ -f "/nextcloud_aio_volumes/nextcloud_aio_database_dump/database-dump.sql" ]; then
        echo "database-dump is missing. cannot perform backup"
        exit 1
    fi

    # Test that nothing is empty
    for directory in "${VOLUME_DIRS[@]}"; do
        if [ -z "$(ls -A "$directory")" ] && [ "$directory" != "/nextcloud_aio_volumes/nextcloud_aio_elasticsearch" ]; then
            echo "$directory is empty which is not allowed."
            exit 1
        fi
    done

    if [ -f "/nextcloud_aio_volumes/nextcloud_aio_database_dump/export.failed" ]; then
        echo "Database export failed the last time. Most likely was the export time not high enough."
        echo "Cannot create a backup now."
        echo "Please report this to https://github.com/nextcloud/all-in-one/issues. Thanks!"
        exit 1
    fi

    # Create backup folder
    mkdir -p "$BORG_BACKUP_DIRECTORY"

    # Initialize the repository if the target is empty
    if ! [ -f "$BORG_BACKUP_DIRECTORY/config" ]; then
        # Don't initialize if already initialized
        if [ -f "/nextcloud_aio_volumes/nextcloud_aio_mastercontainer/data/borg.config" ]; then
            echo "Cannot initialize a new repository as that was already done at least one time."
            echo "If you still want to do so, you may delete the 'borg.config' file that is stored in the mastercontainer volume manually, which will allow you to initialize a new borg repository in the chosen directory:"
            echo "sudo docker exec nextcloud-aio-mastercontainer rm /mnt/docker-aio-config/data/borg.config"
            exit 1
        fi

        echo "initializing repository..."
        NEW_REPOSITORY=1
        if ! borg init --debug --encryption=repokey-blake2 "$BORG_BACKUP_DIRECTORY"; then
            echo "Could not initialize borg repository."
            rm -f "$BORG_BACKUP_DIRECTORY/config"
            exit 1
        fi
        borg config "$BORG_BACKUP_DIRECTORY" additional_free_space 2G

        # Fix too large Borg cache
        # https://borgbackup.readthedocs.io/en/stable/faq.html#the-borg-cache-eats-way-too-much-disk-space-what-can-i-do
        BORG_ID="$(borg config "$BORG_BACKUP_DIRECTORY" id)"
        rm -r "/root/.cache/borg/$BORG_ID/chunks.archive.d"
        touch "/root/.cache/borg/$BORG_ID/chunks.archive.d"

        # Make a backup from the borg config file
        if ! [ -f "$BORG_BACKUP_DIRECTORY/config" ]; then
            echo "The borg config file wasn't created. Something is wrong."
            exit 1
        fi
        rm -f "/nextcloud_aio_volumes/nextcloud_aio_mastercontainer/data/borg.config"
        if ! cp "$BORG_BACKUP_DIRECTORY/config" "/nextcloud_aio_volumes/nextcloud_aio_mastercontainer/data/borg.config"; then
            echo "Could not copy config file to second place. Cannot perform backup."
            exit 1
        fi

        echo "Repository successfully initialized."
    fi

    # Perform backup
    echo "Performing backup..."

    # Borg options
    # auto,zstd compression seems to has the best ratio based on:
    # https://forum.level1techs.com/t/optimal-compression-for-borg-backups/145870/6
    BORG_OPTS=(-v --stats --compression "auto,zstd" --exclude-caches --checkpoint-interval 86400)

    # Create the backup
    echo "Starting the backup..."
    get_start_time
    if ! borg create "${BORG_OPTS[@]}" "$BORG_BACKUP_DIRECTORY::$CURRENT_DATE-nextcloud-aio" "/nextcloud_aio_volumes/"; then
        echo "Deleting the failed backup archive..."
        borg delete --stats "$BORG_BACKUP_DIRECTORY::$CURRENT_DATE-nextcloud-aio"
        echo "Backup failed!"
        if [ "$NEW_REPOSITORY" = 1 ]; then
            echo "Deleting borg.config file so that you can choose a different location for the backup."
            rm "/nextcloud_aio_volumes/nextcloud_aio_mastercontainer/data/borg.config"
        fi
        exit 1
    fi

    # Remove the update skip file because the backup was successful
    rm -f "/nextcloud_aio_volumes/nextcloud_aio_nextcloud_data/skip.update"

    # Prune options
    BORG_PRUNE_OPTS=(--stats --keep-within=7d --keep-weekly=4 --keep-monthly=6 "$BORG_BACKUP_DIRECTORY")

    # Prune archives
    echo "Pruning the archives..."
    if ! borg prune --glob-archives '*_*-nextcloud-aio' "${BORG_PRUNE_OPTS[@]}"; then
        echo "Failed to prune archives!"
        exit 1
    fi

    # Compact archives
    echo "Compacting the archives..."
    if ! borg compact "$BORG_BACKUP_DIRECTORY"; then
        echo "Failed to compact archives!"
        exit 1
    fi

    # Back up additional directories of the host
    if [ "$ADDITIONAL_DIRECTORIES_BACKUP" = 'yes' ]; then
        if [ -d "/docker_volumes/" ]; then
            DOCKER_VOLUME_DIRS="$(find /docker_volumes -mindepth 1 -maxdepth 1 -type d)"
            mapfile -t DOCKER_VOLUME_DIRS <<< "$DOCKER_VOLUME_DIRS"
            for directory in "${DOCKER_VOLUME_DIRS[@]}"; do
                if [ -z "$(ls -A "$directory")" ]; then
                    echo "$directory is empty which is not allowed."
                    exit 1
                fi
            done
            echo "Starting the backup for additional volumes..."
            if ! borg create "${BORG_OPTS[@]}" "$BORG_BACKUP_DIRECTORY::$CURRENT_DATE-additional-docker-volumes" "/docker_volumes/"; then
                echo "Deleting the failed backup archive..."
                borg delete --stats "$BORG_BACKUP_DIRECTORY::$CURRENT_DATE-additional-docker-volumes"
                echo "Backup of additional docker-volumes failed!"
                exit 1
            fi
            echo "Pruning additional volumes..."
            if ! borg prune --glob-archives '*_*-additional-docker-volumes' "${BORG_PRUNE_OPTS[@]}"; then
                echo "Failed to prune additional docker-volumes archives!"
                exit 1
            fi
            echo "Compacting additional volumes..."
            if ! borg compact "$BORG_BACKUP_DIRECTORY"; then
                echo "Failed to compact archives!"
                exit 1
            fi
        fi
        if [ -d "/host_mounts/" ]; then
            EXCLUDED_DIRECTORIES=(home/*/.cache root/.cache var/cache lost+found run var/run dev tmp sys proc)
            # Exclude borg backup cache
            EXCLUDED_DIRECTORIES+=(var/lib/docker/volumes/nextcloud_aio_backup_cache/_data)
            # Exclude target directory
            if [ -n "$BORGBACKUP_HOST_LOCATION" ] && [ "$BORGBACKUP_HOST_LOCATION" != "nextcloud_aio_backupdir" ]; then
                EXCLUDED_DIRECTORIES+=("$BORGBACKUP_HOST_LOCATION")
            fi
            for directory in "${EXCLUDED_DIRECTORIES[@]}"
            do
                EXCLUDE_DIRS+=(--exclude "/host_mounts/$directory/")
            done
            echo "Starting the backup for additional host mounts..."
            if ! borg create "${BORG_OPTS[@]}" "${EXCLUDE_DIRS[@]}" "$BORG_BACKUP_DIRECTORY::$CURRENT_DATE-additional-host-mounts" "/host_mounts/"; then
                echo "Deleting the failed backup archive..."
                borg delete --stats "$BORG_BACKUP_DIRECTORY::$CURRENT_DATE-additional-host-mounts"
                echo "Backup of additional host-mounts failed!"
                exit 1
            fi
            echo "Pruning additional host mounts..."
            if ! borg prune --glob-archives '*_*-additional-host-mounts' "${BORG_PRUNE_OPTS[@]}"; then
                echo "Failed to prune additional host-mount archives!"
                exit 1
            fi
            echo "Compacting additional host mounts..."
            if ! borg compact "$BORG_BACKUP_DIRECTORY"; then
                echo "Failed to compact archives!"
                exit 1
            fi
        fi
    fi

    # Inform user
    get_expiration_time
    echo "Backup finished successfully on $END_DATE_READABLE ($DURATION_READABLE)"
    if [ -f "/nextcloud_aio_volumes/nextcloud_aio_nextcloud_data/update.failed" ]; then
        echo "However a Nextcloud update failed. So reporting that the backup failed which will skip any update attempt the next time."
        echo "Please restore a backup from before the failed Nextcloud update attempt."
        exit 1
    fi
    exit 0
fi

# Do the restore
if [ "$BORG_MODE" = restore ]; then
    get_start_time

    # Perform the restore
    if [ -n "$SELECTED_RESTORE_TIME" ]; then
        SELECTED_ARCHIVE="$(borg list "$BORG_BACKUP_DIRECTORY" | grep "nextcloud-aio" | grep "$SELECTED_RESTORE_TIME" | awk -F " " '{print $1}' | head -1)"
    else
        SELECTED_ARCHIVE="$(borg list "$BORG_BACKUP_DIRECTORY" | grep "nextcloud-aio" | awk -F " " '{print $1}' | sort -r | head -1)"
    fi
    echo "Restoring '$SELECTED_ARCHIVE'..."
    mkdir -p /tmp/borg
    if ! borg mount "$BORG_BACKUP_DIRECTORY::$SELECTED_ARCHIVE" /tmp/borg; then
        echo "Could not mount the backup!"
        exit 1
    fi

    # Save Additional Backup dirs
    if [ -f "/nextcloud_aio_volumes/nextcloud_aio_mastercontainer/data/additional_backup_directories" ]; then
        ADDITIONAL_BACKUP_DIRECTORIES="$(cat /nextcloud_aio_volumes/nextcloud_aio_mastercontainer/data/additional_backup_directories)"
    fi

    # Save daily backup time
    if [ -f "/nextcloud_aio_volumes/nextcloud_aio_mastercontainer/data/daily_backup_time" ]; then
        DAILY_BACKUPTIME="$(cat /nextcloud_aio_volumes/nextcloud_aio_mastercontainer/data/daily_backup_time)"
    fi

    # Restore everything except the configuration file
    if ! rsync --stats --archive --human-readable -vv --delete \
    --exclude "nextcloud_aio_apache/caddy/"** \
    --exclude "nextcloud_aio_mastercontainer/caddy/"** \
    --exclude "nextcloud_aio_mastercontainer/certs/"** \
    --exclude "nextcloud_aio_mastercontainer/data/configuration.json" \
    --exclude "nextcloud_aio_mastercontainer/data/daily_backup_running" \
    --exclude "nextcloud_aio_mastercontainer/data/session_date_file" \
    --exclude "nextcloud_aio_mastercontainer/session/"** \
    /tmp/borg/nextcloud_aio_volumes/ /nextcloud_aio_volumes; then
        echo "Something failed while restoring from backup."
        umount /tmp/borg
        exit 1
    fi

    # Save current aio password
    AIO_PASSWORD="$(jq '.password' /nextcloud_aio_volumes/nextcloud_aio_mastercontainer/data/configuration.json)"

    # Save current path
    BORG_LOCATION="$(jq '.borg_backup_host_location' /nextcloud_aio_volumes/nextcloud_aio_mastercontainer/data/configuration.json)"

    # Save current nextcloud datadir
    if grep -q '"nextcloud_datadir":' /nextcloud_aio_volumes/nextcloud_aio_mastercontainer/data/configuration.json; then
        NEXTCLOUD_DATADIR="$(jq '.nextcloud_datadir' /nextcloud_aio_volumes/nextcloud_aio_mastercontainer/data/configuration.json)"
    else
        NEXTCLOUD_DATADIR='""'
    fi

    # Restore the configuration file
    if ! rsync --archive --human-readable -vv \
    /tmp/borg/nextcloud_aio_volumes/nextcloud_aio_mastercontainer/data/configuration.json \
    /nextcloud_aio_volumes/nextcloud_aio_mastercontainer/data/configuration.json; then
        echo "Something failed while restoring the configuration.json."
        umount /tmp/borg
        exit 1
    fi

    # Set backup-mode to restore since it was a restore
    CONTENTS="$(jq '."backup-mode" = "restore"' /nextcloud_aio_volumes/nextcloud_aio_mastercontainer/data/configuration.json)"
    echo -E "${CONTENTS}" > /nextcloud_aio_volumes/nextcloud_aio_mastercontainer/data/configuration.json

    # Reset the backup path to the currently used one
    CONTENTS="$(jq ".borg_backup_host_location = $BORG_LOCATION" /nextcloud_aio_volumes/nextcloud_aio_mastercontainer/data/configuration.json)"
    echo -E "${CONTENTS}" > /nextcloud_aio_volumes/nextcloud_aio_mastercontainer/data/configuration.json

    # Reset the AIO password to the currently used one
    CONTENTS="$(jq ".password = $AIO_PASSWORD" /nextcloud_aio_volumes/nextcloud_aio_mastercontainer/data/configuration.json)"
    echo -E "${CONTENTS}" > /nextcloud_aio_volumes/nextcloud_aio_mastercontainer/data/configuration.json

    # Reset the datadir to the one that was used for the restore
    CONTENTS="$(jq ".nextcloud_datadir = $NEXTCLOUD_DATADIR" /nextcloud_aio_volumes/nextcloud_aio_mastercontainer/data/configuration.json)"
    echo -E "${CONTENTS}" > /nextcloud_aio_volumes/nextcloud_aio_mastercontainer/data/configuration.json

    # Reset the additional backup directories
    if [ -n "$ADDITIONAL_BACKUP_DIRECTORIES" ]; then
        echo "$ADDITIONAL_BACKUP_DIRECTORIES" > "/nextcloud_aio_volumes/nextcloud_aio_mastercontainer/data/additional_backup_directories"
        chown 33:0 "/nextcloud_aio_volumes/nextcloud_aio_mastercontainer/data/additional_backup_directories"
        chmod 770 "/nextcloud_aio_volumes/nextcloud_aio_mastercontainer/data/additional_backup_directories"
    fi

    # Reset the additional backup directories
    if [ -n "$DAILY_BACKUPTIME" ]; then
        echo "$DAILY_BACKUPTIME" > "/nextcloud_aio_volumes/nextcloud_aio_mastercontainer/data/daily_backup_time"
        chown 33:0 "/nextcloud_aio_volumes/nextcloud_aio_mastercontainer/data/daily_backup_time"
        chmod 770 "/nextcloud_aio_volumes/nextcloud_aio_mastercontainer/data/daily_backup_time"
    fi

    umount /tmp/borg

    # Inform user
    get_expiration_time
    echo "Restore finished successfully on $END_DATE_READABLE ($DURATION_READABLE)"

    # Add file to Nextcloud container so that it skips any update the next time
    touch "/nextcloud_aio_volumes/nextcloud_aio_nextcloud_data/skip.update"
    chmod 777 "/nextcloud_aio_volumes/nextcloud_aio_nextcloud_data/skip.update"

    # Add file to Nextcloud container so that it performs a fingerprint update the next time
    touch "/nextcloud_aio_volumes/nextcloud_aio_nextcloud_data/fingerprint.update"
    chmod 777 "/nextcloud_aio_volumes/nextcloud_aio_nextcloud_data/fingerprint.update"

    # Delete redis cache
    rm -f "/mnt/redis/dump.rdb"
fi

# Do the Backup check
if [ "$BORG_MODE" = check ]; then
    get_start_time
    echo "Checking the backup integrity..."

    # Perform the check
    if ! borg check -v --verify-data "$BORG_BACKUP_DIRECTORY"; then
        echo "Some errors were found while checking the backup integrity!"
        exit 1
    fi

    # Inform user
    get_expiration_time
    echo "Check finished successfully on $END_DATE_READABLE ($DURATION_READABLE)"
    exit 0
fi

# Do the Backup check-repair
if [ "$BORG_MODE" = "check-repair" ]; then
    get_start_time
    echo "Checking the backup integrity and repairing it..."

    # Perform the check-repair
    if ! echo YES | borg check -v --repair "$BORG_BACKUP_DIRECTORY"; then
        echo "Some errors were found while checking and repairing the backup integrity!"
        exit 1
    fi

    # Inform user
    get_expiration_time
    echo "Check finished successfully on $END_DATE_READABLE ($DURATION_READABLE)"
    exit 0
fi

# Do the backup test
if [ "$BORG_MODE" = test ]; then
    if ! [ -d "$BORG_BACKUP_DIRECTORY" ]; then
        echo "No 'borg' directory in the given backup directory found!"
        echo "Only the files/folders below have been found in the given directory."
        ls -a "$MOUNT_DIR"
        echo "Please adjust the directory so that the borg archive is positioned in a folder named 'borg' inside the given directory!"
        exit 1
    elif ! [ -f "$BORG_BACKUP_DIRECTORY/config" ]; then
        echo "A 'borg' directory was found but could not find the borg archive."
        echo "Only the files/folders below have been found in the borg directory."
        ls -a "$BORG_BACKUP_DIRECTORY"
        echo "The archive and most importantly the config file must be positioned directly in the 'borg' subfolder."
        exit 1
    elif ! borg list "$BORG_BACKUP_DIRECTORY"; then
        echo "The entered path seems to be valid but could not open the backup archive."
        echo "Most likely the entered password was wrong so please adjust it accordingly!"
        exit 1
    else
        echo "Everything looks fine so feel free to continue!"
        exit 0
    fi
fi