#!/usr/bin/env bash

#
# Restores all files/folders inside a particular bucket path for the next 7 days. This uses the bulk retrieval tier:
#
# Bulk retrievals are the lowest-cost retrieval option when restoring objects
# from S3 Glacier Deep Archive. They typically finish within 48 hours for
# objects stored in the S3 Glacier Deep Archive storage class or S3
# Intelligent-Tiering Deep Archive tier.
#
# If you need faster access then use the `Expedited` or `Standard` tiers.
#
# Example usage:
#
# aws-restore-deep-glacier-folder my-deep-glacier-bucket path/to/images restored_images
#
# This will create a run.sh script in a folder called "restored_images". Run that to restore all files inside the `path/to/images` folder inside the my-deep-glacier bucket.
#
# After you run the generated script, you have to wait for AWS to make the files available for download. You can check the status of a file with:
#
# aws s3api head-object --bucket my-deep-glacier --key path/to/images/photo1.jpg
#
# (obviously change the bucket and path to suit your needs).
#
# Once the files are restored you can download them on the S3 website or better yet use RcloneBrowser. I'm sure there's also a way to do it over cli too, I just haven't checked.
#
# You'll need the aws cli tools for this script. Download them from https://docs.aws.amazon.com/cli/latest/userguide/getting-started-install.html
# Once installed, open a new shell and verify that you can run the `aws` command.
#
# If you see an error like along the lines of "'charmap' codec can't encode
# character '\u200e' in position 42: character maps to <undefined>" then that
# means a filename has a Unicode codepoint and the dumb aws Python code is
# trying to read it using your system's locale, which is very likely not set to
# use the Windows UTF-8 beta feature. This is an ongoing issue in this tool
# that goes back to 2013!!! There's no way to fix it using environment
# variables, at least nothing worked for me. The fix provided by the devs is
# heavy handed: you change your system locale to use UTF-8... This has
# consequences though like breaking legacy apps that don't have Unicode support
# and I'm sure other weird things will happen, such as file corruption. Anyway,
# if you're getting this charmap error then I suggest changing your system
# locale, run this again, then switch back to your previous locale. If you
# don't get the canonical file name then you won't be able to restore it.
#
# You can enable the UTF-8 locale with:
#
# win+r -> intl.cpl -> Administrative tab -> Change system locale -> Beta: Use Unicode UTF-8 box.
#

if which tput >/dev/null 2>&1; then
    ncolors=$(tput colors)
fi
if [ -t 1 ] && [ -n "$ncolors" ] && [ "$ncolors" -ge 8 ]; then
    RED="$(tput setaf 1)"
    GREEN="$(tput setaf 2)"
    YELLOW="$(tput setaf 3)"
    BLUE="$(tput setaf 4)"
    MAGENTA="$(tput setaf 5)"
    CYAN="$(tput setaf 6)"
    BOLD="$(tput bold)"
    NORMAL="$(tput sgr0)"
else
    RED=""
    GREEN=""
    YELLOW=""
    BLUE=""
    MAGENTA=""
    CYAN=""
    BOLD=""
    NORMAL=""
fi

error() {
    printf "${BOLD}${RED}$1${NORMAL}\n"
}

abort() {
  error "\nAborting...\n"
  exit 1
}

set -e

bucket="$1"
path="$2"
temp_dir="$3"
number_of_objects_per_file=100
days_available=7
restore_tier="Bulk" # Can also be "Standard" or "Expedited"

if [[ $bucket == "" || $path == "" || $temp_dir == "" ]]; then
    error "Usage: aws-restore-deep-glacier-folder <bucket-name> <path-in-bucket> <local-temp-dir>"
    exit 1
fi

printf "Restoring ${BOLD}${GREEN}$bucket:$path${NORMAL} with local temp folder ${BOLD}${GREEN}$temp_dir${NORMAL}\n"

mkdir -p "$temp_dir"
pushd "$temp_dir" &>/dev/null

items="$(aws s3api list-objects-v2 --bucket $bucket --prefix $path --query "Contents[?StorageClass=='DEEP_ARCHIVE']" --output text)"

error=$?
if [[ ! $error -eq 0 ]]; then
    error "Error: failed to run the aws command. Aborting."
    exit 1
fi

if [[ $items == "None" ]]; then
    error "Didn't find any files. Check that your bucket name and path is correct."
    exit 1
fi

# Format the items list.
output="$(echo "$items" | LC_ALL=C awk '{print substr($0, index($0, $2))}' | awk '{NF-=3};3')"

mapfile -t lines_array <<< "$output"
num_items="${#lines_array[@]}"

printf "Number of items to restore: ${BOLD}${YELLOW}$num_items${NORMAL}\n"
printf "${BOLD}${RED}Proceed?\n> ${NORMAL}"
read -e proceed
if [[ $proceed == "1" || $proceed == "y" || $proceed == "Y" || $proceed == "yes" || $proceed == "YES" ]]; then
    echo "$output" > all_objects_list.txt

    # Generate the main script that will kick off the restoration.
    printf "while read x; do\n    printf \"aws s3api restore-object --restore-request '{\\\\\"Days\\\\\":$days_available,\\\\\"GlacierJobParameters\\\\\":{\\\\\"Tier\\\\\":\\\\\"$restore_tier\\\\\"}}' --bucket $bucket --key \\\\\"\$x\\\\\"\\\\n\"\n    aws s3api restore-object --restore-request \"{\\\\\"Days\\\\\":$days_available,\\\\\"GlacierJobParameters\\\\\":{\\\\\"Tier\\\\\":\\\\\"$restore_tier\\\\\"}}\" --bucket $bucket --key \"\$x\"\ndone < all_objects_list.txt\nprintf \"\\\\nDone! You can now delete this folder.\\\\nYour files are currently being restored. The time it takes to restore can be found in the AWS docs - just look for the $restore_tier restore tier, which is what you used.\\\\nOnce restored, download the files from the S3 site or better yet use RCloneBrowser.\\\\n\"\n" > run.sh
    chmod +x run.sh

    printf "${BOLD}You can now run ${GREEN}$temp_dir/run.sh${NORMAL}${BOLD} to start the restoration process.\n"
else
    echo Aborting.
fi

popd &>/dev/null