#!/bin/bash

set -u 
set -e

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

# Update configuration file according to value 
config_set() {
	local value="$1"
	local file="$2"

    jq "$value" "$file" > "$file.tmp"
    mv "$file.tmp" "$file"
}

# Parse environment variables 
chmod +x /parseurl.py
/parseurl.py MM_DB_
eval "$(/parseurl.py MM_DB_)"

# Read environment variables or set default values
DB_HOST=${DB_HOST:-db}
DB_PORT_NUMBER=${DB_PORT_NUMBER:-5432}
MM_USERNAME=${MM_USERNAME:-mmuser}
MM_PASSWORD=${MM_PASSWORD:-mmuser_password}
MM_DBNAME=${MM_DBNAME:-mattermost}
MM_CONFIG=${MM_CONFIG:-/mattermost/config/config.json}

if [ "${1:0:1}" = '-' ]; then
    set -- platform "$@"
fi

if [ "$1" = 'platform' ]; then
  # Check CLI args for a -config option
  for ARG in "$@";
  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
    config_set '.ServiceSettings.ListenAddress = ":80"' "$MM_CONFIG" 
    config_set '.LogSettings.EnableConsole = false' "$MM_CONFIG" 
    config_set '.LogSettings.ConsoleLevel = "INFO"' "$MM_CONFIG" 
    config_set '.FileSettings.Directory = "/mattermost/data/"' "$MM_CONFIG"
    config_set '.FileSettings.EnablePublicLink = true' "$MM_CONFIG" 
    config_set ".FileSettings.PublicLinkSalt = \"$(generate_salt)\"" "$MM_CONFIG"
    config_set '.EmailSettings.SendEmailNotifications = false' "$MM_CONFIG"
    config_set '.EmailSettings.FeedbackEmail = ""' "$MM_CONFIG"
    config_set '.EmailSettings.SMTPServer = ""' "$MM_CONFIG" 
    config_set '.EmailSettings.SMTPPort = ""' "$MM_CONFIG"
    config_set ".EmailSettings.InviteSalt = \"$(generate_salt)\"" "$MM_CONFIG"
    config_set ".EmailSettings.PasswordResetSalt = \"$(generate_salt)\"" "$MM_CONFIG"
    config_set '.RateLimitSettings.Enable = true' "$MM_CONFIG"
    config_set '.SqlSettings.DriverName = "postgres"' "$MM_CONFIG"
    config_set ".SqlSettings.AtRestEncryptKey = \"$(generate_salt)\"" "$MM_CONFIG" 
  else
    echo "Using existing config file" "$MM_CONFIG"
  fi

  # Configure database access
  if [ -z "$MM_SQLSETTINGS_DATASOURCE" ]
  then
    echo -ne "Configure database connection..."
    export MM_SQLSETTINGS_DATASOURCE="postgres://$MM_USERNAME:$MM_PASSWORD@$DB_HOST:$DB_PORT_NUMBER/$MM_DBNAME?sslmode=disable&connect_timeout=10"
    echo OK
  else
    echo "Using existing database connection"
  fi

  # Wait for database to be reachable
  echo "Wait until database $DB_HOST:$DB_PORT_NUMBER is ready..."
  until nc -z "$DB_HOST" "$DB_PORT_NUMBER"
  do
    sleep 1
  done

  # 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 platform"
fi

exec "$@"