# Extract a key from a plain command output
#
# example: yunohost user info tata --output-as plain | ynh_get_plain_key mail
#
# usage: ynh_get_plain_key key [subkey [subsubkey ...]]
# | ret: string - the key's value
ynh_get_plain_key() {
    prefix="#"
    founded=0
    key=$1
    shift
    while read line; do
        if [[ "$founded" == "1" ]] ; then
            [[ "$line" =~ ^${prefix}[^#] ]] && return
            echo $line
        elif [[ "$line" =~ ^${prefix}${key}$ ]]; then
            if [[ -n "${1:-}" ]]; then
                prefix+="#"
                key=$1
                shift
            else
                founded=1
            fi
        fi
    done
}

# Restore a previous backup if the upgrade process failed
#
# usage:
# ynh_backup_before_upgrade
# ynh_clean_setup () {
# 	ynh_backup_after_failed_upgrade
# }
# ynh_abort_if_errors
#
ynh_backup_after_failed_upgrade () {
	echo "Upgrade failed." >&2
	app_bck=${app//_/-}	# Replace all '_' by '-'
	
        # Check if an existing backup can be found before removing and restoring the application.
	if sudo yunohost backup list | grep -q $app_bck-pre-upgrade$backup_number
    	then
		# Remove the application then restore it
		sudo yunohost app remove $app
		# Restore the backup
		sudo yunohost backup restore --ignore-system $app_bck-pre-upgrade$backup_number --apps $app --force
		ynh_die "The app was restored to the way it was before the failed upgrade."
	fi
}

# Make a backup in case of failed upgrade
#
# usage:
# ynh_backup_before_upgrade
# ynh_clean_setup () {
# 	ynh_backup_after_failed_upgrade
# }
# ynh_abort_if_errors
#
ynh_backup_before_upgrade () {
	backup_number=1
	old_backup_number=2
	app_bck=${app//_/-}	# Replace all '_' by '-'
	
    	# Check if a backup already exists with the prefix 1
	if sudo yunohost backup list | grep -q $app_bck-pre-upgrade1
    	then
        	# Prefix becomes 2 to preserve the previous backup
		backup_number=2
		old_backup_number=1
	fi

	# Create backup
	sudo yunohost backup create --ignore-system --apps $app --name $app_bck-pre-upgrade$backup_number
	if [ "$?" -eq 0 ]
    	then
		# If the backup succeeded, remove the previous backup
		if sudo yunohost backup list | grep -q $app_bck-pre-upgrade$old_backup_number
		then
			# Remove the previous backup only if it exists
			sudo yunohost backup delete $app_bck-pre-upgrade$old_backup_number > /dev/null
		fi
	else
		ynh_die "Backup failed, the upgrade process was aborted."
	fi

# Download, check integrity, uncompress and patch the source from app.src
#
# The file conf/app.src need to contains:
# 
# SOURCE_URL=Address to download the app archive
# SOURCE_SUM=Control sum
# # (Optional) Program to check the integrity (sha256sum, md5sum...)
# # default: sha256
# SOURCE_SUM_PRG=sha256
# # (Optional) Archive format
# # default: tar.gz
# SOURCE_FORMAT=tar.gz
# # (Optional) Put false if sources are directly in the archive root
# # default: true
# SOURCE_IN_SUBDIR=false
# # (Optionnal) Name of the local archive (offline setup support)
# # default: ${src_id}.${src_format}
# SOURCE_FILENAME=example.tar.gz 
#
# Details:
# This helper downloads sources from SOURCE_URL if there is no local source
# archive in /opt/yunohost-apps-src/APP_ID/SOURCE_FILENAME
# 
# Next, it checks the integrity with "SOURCE_SUM_PRG -c --status" command.
# 
# If it's ok, the source archive will be uncompressed in $dest_dir. If the
# SOURCE_IN_SUBDIR is true, the first level directory of the archive will be
# removed.
#
# Finally, patches named sources/patches/${src_id}-*.patch and extra files in
# sources/extra_files/$src_id will be applied to dest_dir
#
#
# usage: ynh_setup_source dest_dir [source_id]
# | arg: dest_dir  - Directory where to setup sources
# | arg: source_id - Name of the app, if the package contains more than one app
ynh_setup_source () {
    local dest_dir=$1
    local src_id=${2:-app} # If the argument is not given, source_id equals "app"
    
    # Load value from configuration file (see above for a small doc about this file
    # format)
    local src_url=$(grep 'SOURCE_URL=' "$YNH_CWD/../conf/${src_id}.src" | cut -d= -f2-)
    local src_sum=$(grep 'SOURCE_SUM=' "$YNH_CWD/../conf/${src_id}.src" | cut -d= -f2-)
    local src_sumprg=$(grep 'SOURCE_SUM_PRG=' "$YNH_CWD/../conf/${src_id}.src" | cut -d= -f2-)
    local src_format=$(grep 'SOURCE_FORMAT=' "$YNH_CWD/../conf/${src_id}.src" | cut -d= -f2-)
    local src_in_subdir=$(grep 'SOURCE_IN_SUBDIR=' "$YNH_CWD/../conf/${src_id}.src" | cut -d= -f2-)
    local src_filename=$(grep 'SOURCE_FILENAME=' "$YNH_CWD/../conf/${src_id}.src" | cut -d= -f2-)
    
    # Default value
    src_sumprg=${src_sumprg:-sha256sum}
    src_in_subdir=${src_in_subdir:-true}
    src_format=${src_format:-tar.gz}
    src_format=$(echo "$src_format" | tr '[:upper:]' '[:lower:]')
    if [ "$src_filename" = "" ] ; then
        src_filename="${src_id}.${src_format}"
    fi
    local local_src="/opt/yunohost-apps-src/${YNH_APP_ID}/${src_filename}"

    if test -e "$local_src"
    then    # Use the local source file if it is present
        cp $local_src $src_filename
    else    # If not, download the source
        wget -nv -O $src_filename $src_url
    fi

    # Check the control sum
    echo "${src_sum} ${src_filename}" | ${src_sumprg} -c --status \
        || ynh_die "Corrupt source"

    # Extract source into the app dir
    mkdir -p "$dest_dir"
    if [ "$src_format" = "zip" ]
    then 
        # Zip format
        # Using of a temp directory, because unzip doesn't manage --strip-components
        if $src_in_subdir ; then
            local tmp_dir=$(mktemp -d)
            unzip -quo $src_filename -d "$tmp_dir"
            cp -a $tmp_dir/*/. "$dest_dir"
            ynh_secure_remove "$tmp_dir"
        else
            unzip -quo $src_filename -d "$dest_dir"
        fi
    else
        local strip=""
        if $src_in_subdir ; then
            strip="--strip-components 1"
        fi
        if [[ "$src_format" =~ ^tar.gz|tar.bz2|tar.xz$ ]] ; then
            tar -xf $src_filename -C "$dest_dir" $strip
        else
            ynh_die "Archive format unrecognized."
        fi
    fi

    # Apply patches
    if (( $(find $YNH_CWD/../sources/patches/ -type f -name "${src_id}-*.patch" 2> /dev/null | wc -l) > "0" )); then
        local old_dir=$(pwd)
        (cd "$dest_dir" \
            && for p in $YNH_CWD/../sources/patches/${src_id}-*.patch; do \
                patch -p1 < $p; done) \
            || ynh_die "Unable to apply patches"
        cd $old_dir
    fi

    # Add supplementary files
    if test -e "$YNH_CWD/../sources/extra_files/${src_id}"; then
        cp -a $YNH_CWD/../sources/extra_files/$src_id/. "$dest_dir"
    fi
}

# Curl abstraction to help with POST requests to local pages (such as installation forms)
#
# $domain and $path_url should be defined externally (and correspond to the domain.tld and the /path (of the app?))
#
# example: ynh_local_curl "/install.php?installButton" "foo=$var1" "bar=$var2"
# 
# usage: ynh_local_curl "page_uri" "key1=value1" "key2=value2" ...
# | arg: page_uri    - Path (relative to $path_url) of the page where POST data will be sent
# | arg: key1=value1 - (Optionnal) POST key and corresponding value
# | arg: key2=value2 - (Optionnal) Another POST key and corresponding value
# | arg: ...         - (Optionnal) More POST keys and values
ynh_local_curl () {
	# Define url of page to curl
	full_page_url=https://localhost$path_url$1

	# Concatenate all other arguments with '&' to prepare POST data
	POST_data=""
	for arg in "${@:2}"
	do
		POST_data="${POST_data}${arg}&"
	done
	if [ -n "$POST_data" ]
	then
		# Add --data arg and remove the last character, which is an unecessary '&'
		POST_data="--data ${POST_data::-1}"
	fi

	# Curl the URL
	curl --silent --show-error -kL -H "Host: $domain" --resolve $domain:443:127.0.0.1 $POST_data "$full_page_url"
}