#!/bin/bash

#=================================================
# PACKAGE UPDATING HELPER
#=================================================

# This script is meant to be run by GitHub Actions
# The YunoHost-Apps organisation offers a template Action to run this script periodically
# Since each app is different, maintainers can adapt its contents so as to perform
# automatic actions when a new upstream release is detected.

# Remove this exit command when you are ready to run this Action
# exit 1

#=================================================
# FETCHING LATEST RELEASE AND ITS ASSETS
#=================================================

# Fetching information
current_version=$(jq -j '.version|split("~")[0]' manifest.json)
repo=$(jq -j '.upstream.code|split("https://github.com/")[1]' manifest.json)
# Some jq magic is needed, because the latest upstream release is not always the latest version (e.g. security patches for older versions)
version=$(curl --silent "https://api.github.com/repos/$repo/releases" | jq -r '.[] | select( .prerelease != true ) | .tag_name' | sort -V | tail -1)
assets=($(curl --silent "https://api.github.com/repos/$repo/releases" | jq -r '[ .[] | select(.tag_name=="'"$version"'").assets[].browser_download_url ] | join(" ") | @sh' | tr -d "'"))

# Later down the script, we assume the version has only digits and dots
# Sometimes the release name starts with a "v", so let's filter it out.
# You may need more tweaks here if the upstream repository has different naming conventions. 
if [[ ${version:0:1} == "v" || ${version:0:1} == "V" ]]; then
    version=${version:1}
fi

# Setting up the environment variables
echo "Current version: $current_version"
echo "Latest release from upstream: $version"
{ echo "VERSION=$version"; echo "REPO=$repo"; } >> "$GITHUB_ENV"
# For the time being, let's assume the script will fail
echo "PROCEED=false" >> "$GITHUB_ENV"

# Proceed only if the retrieved version is greater than the current one
if ! dpkg --compare-versions "$current_version" "lt" "$version" ; then
    echo "::warning ::No new version available"
    exit 0
# Proceed only if a PR for this new version does not already exist
elif git ls-remote -q --exit-code --heads https://github.com/"$GITHUB_REPOSITORY".git ci-auto-update-v"$version" ; then
    echo "::warning ::A branch already exists for this update"
    exit 0
fi

# Each release can hold multiple assets (e.g. binaries for different architectures, source code, etc.)
echo "${#assets[@]} available asset(s)"

#=================================================
# UPDATE SOURCE FILES
#=================================================

# Here we use the $assets variable to get the resources published in the upstream release.
# Here is an example for Grav, it has to be adapted in accordance with how the upstream releases look like.

# Create the temporary directory
tempdir="$(mktemp -d)"

# Download checksums.txt
checksum_file=https://github.com/"$repo"/releases/download/v"$version"/checksums.txt
echo "Downloading checksums file at" "$checksum_file"
curl --silent -4 -L "$checksum_file" -o "$tempdir/checksums.txt"

# Let's loop over the array of assets URLs
for asset_url in "${assets[@]}"; do

echo "Handling asset at $asset_url"

# Assign the asset to a source file in conf/ directory
# Here we base the source file name upon a unique keyword in the assets url (admin vs. update)
# Leave $src empty to ignore the asset
case $asset_url in
  *"linux_386"*)
    src="i386"
    ;;
  *"linux_amd64"*)
    src="x86-64"
    ;;
  *"linux_arm64"*)
    src="arm64"
    ;;
  *"linux_armv6"*)
    src="armv6"
    ;;
  *"linux_armv7"*)
    src="armv7"
    ;;
  *)
    src=""
    ;;
esac

# If $src is not empty, let's process the asset
if [ -n "$src" ]; then

# Get checksum
filename=${asset_url##*/}
checksum=$(grep "$filename" "$tempdir/checksums.txt" | awk '{print $1;}')

# Get extension
if [[ $filename == *.tar.gz ]]; then
  extension=tar.gz
else
  extension=${filename##*.}
fi

# Rewrite source file
cat <<EOT > "conf/$src.src"
SOURCE_URL=$asset_url
SOURCE_SUM=$checksum
SOURCE_SUM_PRG=sha256sum
SOURCE_FORMAT=$extension
SOURCE_EXTRACT=true
SOURCE_IN_SUBDIR=false
SOURCE_FILENAME=$filename
EOT
echo "... conf/$src.src updated"

else
echo "... asset ignored"
fi

done

# Delete temporary directory
rm -rf "$tempdir"

#=================================================
# SPECIFIC UPDATE STEPS
#=================================================

# Any action on the app's source code can be done.
# The GitHub Action workflow takes care of committing all changes after this script ends.

#=================================================
# GENERIC FINALIZATION
#=================================================

# Replace new version in manifest
echo "$(jq -s --indent 4 ".[] | .version = \"$version~ynh1\"" manifest.json)" > manifest.json

# No need to update the README, yunohost-bot takes care of it

# The Action will proceed only if the PROCEED environment variable is set to true
echo "PROCEED=true" >> "$GITHUB_ENV"
exit 0