#!/bin/sh

# Function to generate a random salt
generate_salt() {
	tr -dc 'a-zA-Z0-9' < /dev/urandom | fold -w 48 | head -n 1
}

# Read environment variables or set default values
DB_HOST=${DB_HOST:-db}
DB_PORT_NUMBER=${DB_PORT_NUMBER:-5432}
# see https://www.postgresql.org/docs/current/libpq-ssl.html
# for usage when database connection requires encryption
# filenames should be escaped if they contain spaces
#  i.e. $(printf %s ${MY_ENV_VAR:-''}  | jq -s -R -r @uri)
# the location of the CA file can be set using environment var PGSSLROOTCERT
# the location of the CRL file can be set using PGSSLCRL
# The URL syntax for connection string does not support the parameters
# sslrootcert and sslcrl reliably, so use these PostgreSQL-specified variables
# to set names if using a location other than default
DB_USE_SSL=${DB_USE_SSL:-disable}
MM_DBNAME=${MM_DBNAME:-mattermost}
MM_CONFIG=${MM_CONFIG:-/mattermost/config/config.json}

_1=$(echo "$1" | awk  '{ s=substr($0, 0, 1); print s; }' )
if [ "$_1" = '-' ]; then
	set -- mattermost "$@"
fi

if [ "$1" = 'mattermost' ]; then
	# Check CLI args for a -config option
	for ARG in "$@"; do
		case "$ARG" in
			-config=*) MM_CONFIG=${ARG#*=};;
		esac
	done

	if [ ! -f "$MM_CONFIG" ]; then
		# If there is no configuration file, create it with some default values
		echo "No configuration file $MM_CONFIG"
		echo "Creating a new one"
		# Copy default configuration file
		cp /config.json.save "$MM_CONFIG"
		# Substitute some parameters with jq
		jq '.ServiceSettings.ListenAddress = ":8000"' "$MM_CONFIG" > "$MM_CONFIG.tmp" && mv "$MM_CONFIG.tmp" "$MM_CONFIG"
		jq '.LogSettings.EnableConsole = true' "$MM_CONFIG" > "$MM_CONFIG.tmp" && mv "$MM_CONFIG.tmp" "$MM_CONFIG"
		jq '.LogSettings.ConsoleLevel = "ERROR"' "$MM_CONFIG" > "$MM_CONFIG.tmp" && mv "$MM_CONFIG.tmp" "$MM_CONFIG"
		jq '.FileSettings.Directory = "/mattermost/data/"' "$MM_CONFIG" > "$MM_CONFIG.tmp" && mv "$MM_CONFIG.tmp" "$MM_CONFIG"
		jq '.FileSettings.EnablePublicLink = true' "$MM_CONFIG" > "$MM_CONFIG.tmp" && mv "$MM_CONFIG.tmp" "$MM_CONFIG"
		jq ".FileSettings.PublicLinkSalt = \"$(generate_salt)\"" "$MM_CONFIG" > "$MM_CONFIG.tmp" && mv "$MM_CONFIG.tmp" "$MM_CONFIG"
		jq '.EmailSettings.SendEmailNotifications = false' "$MM_CONFIG" > "$MM_CONFIG.tmp" && mv "$MM_CONFIG.tmp" "$MM_CONFIG"
		jq '.EmailSettings.FeedbackEmail = ""' "$MM_CONFIG" > "$MM_CONFIG.tmp" && mv "$MM_CONFIG.tmp" "$MM_CONFIG"
		jq '.EmailSettings.SMTPServer = ""' "$MM_CONFIG" > "$MM_CONFIG.tmp" && mv "$MM_CONFIG.tmp" "$MM_CONFIG"
		jq '.EmailSettings.SMTPPort = ""' "$MM_CONFIG" > "$MM_CONFIG.tmp" && mv "$MM_CONFIG.tmp" "$MM_CONFIG"
		jq ".EmailSettings.InviteSalt = \"$(generate_salt)\"" "$MM_CONFIG" > "$MM_CONFIG.tmp" && mv "$MM_CONFIG.tmp" "$MM_CONFIG"
		jq ".EmailSettings.PasswordResetSalt = \"$(generate_salt)\"" "$MM_CONFIG" > "$MM_CONFIG.tmp" && mv "$MM_CONFIG.tmp" "$MM_CONFIG"
		jq '.RateLimitSettings.Enable = true' "$MM_CONFIG" > "$MM_CONFIG.tmp" && mv "$MM_CONFIG.tmp" "$MM_CONFIG"
		jq '.SqlSettings.DriverName = "postgres"' "$MM_CONFIG" > "$MM_CONFIG.tmp" && mv "$MM_CONFIG.tmp" "$MM_CONFIG"
		jq ".SqlSettings.AtRestEncryptKey = \"$(generate_salt)\"" "$MM_CONFIG" > "$MM_CONFIG.tmp" && mv "$MM_CONFIG.tmp" "$MM_CONFIG"
		jq '.PluginSettings.Directory = "/mattermost/plugins/"' "$MM_CONFIG" > "$MM_CONFIG.tmp" && mv "$MM_CONFIG.tmp" "$MM_CONFIG"
	else
		echo "Using existing config file $MM_CONFIG"
	fi

	# Configure database access
	if [ -z "$MM_SQLSETTINGS_DATASOURCE" ] && [ -n "$MM_USERNAME" ] && [ -n "$MM_PASSWORD" ]; then
		echo "Configure database connection..."
		# URLEncode the password, allowing for special characters
		ENCODED_PASSWORD=$(printf %s "$MM_PASSWORD" | jq -s -R -r @uri)
		export MM_SQLSETTINGS_DATASOURCE="postgres://$MM_USERNAME:$ENCODED_PASSWORD@$DB_HOST:$DB_PORT_NUMBER/$MM_DBNAME?sslmode=$DB_USE_SSL&connect_timeout=10"
		echo "OK"
	else
		echo "Using existing database connection"
	fi

	# Wait another second for the database to be properly started.
	# Necessary to avoid "panic: Failed to open sql connection pq: the database system is starting up"
	sleep 1

	echo "Starting mattermost"
fi

exec "$@"
