#!/bin/bash


# ----- Usage information -----

print_usage() {
  # Print help for the first argument
  case "$1" in
  # management
    setup)
      echo; echo "Set up the environment for diaspora*"
      echo; echo "This command is an alias for the execution of the commands"
      echo "build, config, bundle, migrate and setup-tests, in that order."
      print_usage_header "setup [options]" \
        "    --force    Rebuild image without using Docker's cache;" \
        "               overwrite existing configuration" \
        "    --mysql    Use MySQL as database (PostgreSQL is default)"
      ;;
    start)
      echo; echo "Start diaspora* (includes database)"
      print_usage_header "start [options]" \
        "-d    Run in background"
      ;;
    stop)
      echo; echo "Stop diaspora* (includes database)"
      print_usage_header "stop"
      ;;
    restart)
      echo; echo "Restart diaspora* using bin/eye (fast restart)"
      print_usage_header "restart [options]" \
        "    --full    Restart entire container"
      ;;
    logs)
      echo; echo "Follow log output of the running diaspora* instance"
      print_usage_header "logs [options]" \
        "-a, --all     Follow all containers, including databases"
      ;;
    status)
      echo; echo "Show currently running diaspora* Docker container(s) and related image(s)"
      print_usage_header "status"
      ;;
    clean)
      echo; echo "Delete diaspora* Docker containers and volumes (includes database)"
      print_usage_header "clean [options]" \
        "    --config    Delete configuration files as well"
      ;;
  # test & development
    cucumber)
      echo; echo "Run cucumber tests"
      echo; echo "The specified cucumber tests will be executed. If none are given, all"
      echo "tests are executed."
      print_usage_header "cucumber [TEST...]"
      ;;
    jasmine)
      echo; echo "Run all jasmine tests"
      print_usage_header "jasmine"
      ;;
    rspec)
      echo; echo "Run rspec tests"
      echo; echo  "The specified rspec tests will be executed. If none are given, all"
      echo "tests will be executed."
      print_usage_header "rspec"
      ;;
    pronto)
      echo; echo "Run pronto checks"
      print_usage_header "pronto"
      ;;
    migrate)
      echo; echo "Execute pending migrations (incl. database setup)"
      print_usage_header "migrate [options]" \
        "-d    Run in background"
      ;;
  # misc
    build)
      echo; echo "(Re-)Build Docker image diaspora:dev-latest"
      print_usage_header "build [options]" \
        "    --no-cache    Rebuild image without using Docker's cache"
      ;;
    bundle)
      echo; echo "Install gems using bundle into $DIASPORA_ROOT"
      print_usage_header "bundle [options]" \
        "-d    Run in background"
      ;;
    config)
      echo; echo "Create basic configuration files for usage with PostgreSQL (default)"
      print_usage_header "config [options]" \
        "    --mysql       Use MySQL as database (PostgreSQL is default)" \
        "    --overwrite   Overwrite existing configuration"
      ;;
    exec)
      echo; echo "Execute a command in a diaspora* Docker container"
      echo; echo "If there is no running diaspora* Docker container, a new one is created"
      echo "and started."
      print_usage_header "exec [options] COMMAND [ARGS...]" \
        "-d    Run in background"
      ;;
    help)
      echo; echo "Show help on a command"
      print_usage_header "help COMMAND"
      ;;
    setup-tests)
      echo; echo "Prepare cached files and database contents for tests"
      print_usage_header "setup-tests"
      ;;
    *)
      print_usage_full
      ;;
  esac
}

print_usage_header() {
  # Print formatted usage information for COMMAND
  # Usage: print_usage_header COMMAND [FLAG_DESCRIPTION...]
  echo; echo "Usage:  $1"
  shift
  if [ $# -gt 0 ]; then
    echo; echo "Options:"
    while [ $# -gt 0 ]; do
      echo "  $1"
      shift
    done
  fi
}

print_usage_full() {
  # Print overview of available commands
  # $SCRIPT_NAME [help|-h|--help] leads here
  echo; echo "Setup and run a diaspora instance for development in no time."
  print_usage_header "$SCRIPT_NAME COMMAND"
  echo
  echo "Management Commands:"
  echo "  setup         Prepare diaspora* to run for development"
  echo "  start         Start diaspora*"
  echo "  stop          Stop diaspora*"
  echo "  restart       Restart of diaspora*"
  echo "  logs          Follow log output of diaspora*"
  echo "  status        Show current instance status of diaspora*"
  echo "  clean         Reset diaspora* instance"
  echo
  echo "Test and Development Commands:"
  echo "  cucumber      Run cucumber tests"
  echo "  jasmine       Run jasmine tests"
  echo "  rspec         Run rspec tests"
  echo "  pronto        Run pronto checks"
  echo "  migrate       Execute pending migrations"
  echo
  echo "Misc. Commands:"
  echo "  build         Build basic diaspora* environment"
  echo "  bundle        (Re-)Install gems for diaspora*"
  echo "  config        Configure diaspora*"
  echo "  exec          Execute a command in the run environment (advanced)"
  echo "  help          Show help for commands"
  echo "  setup-tests   Prepare diaspora* test environment"
  echo
  echo "Run '$SCRIPT_NAME help COMMAND' for more information on a command."
}


# ----- Helper functions -----

dia_docker_compose() {
  # Check permissions of docker socket and use sudo if needed
  if [ -r "/var/run/docker.sock" ] && [ -w "/var/run/docker.sock" ]; then
    docker-compose "$@"
  else
    echo "Attention: Docker socket not writable, using sudo for the docker command. You might be asked for your password now." >&2
    sudo -E docker-compose "$@"
  fi
}

dia_fetch_upstream() {
  # Add and fetch upstream develop branch
  if ! git remote show | grep -q '^upstream$'; then
    git remote add upstream https://github.com/diaspora/diaspora.git
  fi
  git fetch upstream develop
}

dia_is_configured() {
  # Check if config files exist
  [ -f "$DIASPORA_CONFIG_DB" ] && [ -f "$DIASPORA_CONFIG_DIA" ]
}

exit_if_unconfigured() {
  # Exit if config does not seem complete
  if ! dia_is_configured; then
    echo "Fatal: Config files missing. Run the 'setup' or 'config' command to configure."
    exit 1
  fi
}

dia_is_running() {
  # Check if diaspora container is running
  dia_docker_compose ps --services --filter status=running | grep -qx 'diaspora'
}

dia_is_db_running() {
  # Check if db container is running
  dia_docker_compose ps --services --filter status=running | grep -qx $DIASPORA_DOCKER_DB
}

dia_get_db() {
  # Get currently configured or assumed db type
  grep -q '^  <<: \*mysql' "$DIASPORA_CONFIG_DB" 2>/dev/null && echo mysql || echo postgresql
}

# ----- Command functions -----

dia_build() {
  if [ $# -gt 0 ] && [ "$1" == "--no-cache" ]; then nocache="--no-cache"; fi
  # Build the diaspora Docker container (diaspora:dev-latest)
  dia_docker_compose build $nocache diaspora
}

dia_bundle() {
  # Run bundle in order to install all gems into $DIASPORA_ROOT
  # Do not start database, not required and sometimes not yet configured
  echo "Installing gems via bundler ..."
  dia_docker_compose run \
    --rm \
    --no-deps $1 \
    -e DIA_NODB=1 \
    diaspora \
    /bin/sh -c "gem install bundler && script/configure_bundler && bin/bundle install --full-index"
}

dia_clean() {
  # Delete all containers and volumes
  for i in "$@"; do
    case "$i" in
      --config)
        dia_config_delete=1
        ;;
    esac
  done
  dia_docker_compose down -v
  if [ ! -z $dia_config_delete ]; then
    rm "$DIASPORA_CONFIG_DIA" "$DIASPORA_CONFIG_DB"
  fi
}

dia_config() {
  # Create rudimentary configuration files if they don't exist
  echo "Configuring diaspora ..."
  for i in "$@"; do
    case "$i" in
      --mysql)
        dia_config_mysql=1
        ;;
      --overwrite)
        dia_config_delete=1
        ;;
    esac
  done
  [ ! -f "$DIASPORA_ROOT"/public/source.tar.gz ] && touch "$DIASPORA_ROOT"/public/source.tar.gz
  # Delete existing files if requested
  if [ ! -z $dia_config_delete ]; then
    rm "$DIASPORA_CONFIG_DIA" "$DIASPORA_CONFIG_DB"
  fi
  # Create new diaspora.toml if none exists
  if [ ! -f "$DIASPORA_CONFIG_DIA" ]; then
    cp "$DIASPORA_CONFIG_DIA".example "$DIASPORA_CONFIG_DIA"
  fi
  # Select database type
  if [ -z $dia_config_mysql ]; then
    export DIASPORA_DOCKER_DB=postgresql
  else
    export DIASPORA_DOCKER_DB=mysql
  fi
  # Create new database.yml if none exists
  if [ ! -f "$DIASPORA_CONFIG_DB" ]; then
    sed -E '
      /^postgresql/,/^[[:alpha:]]/ {
        s/host:.*/host: postgresql/
        s/password.*/password: postgres/
      }
      /^mysql/,/^[[:alpha:]]/ {
        s/host:.*/host: mysql/
        s/password:.*/password: mysql/
      }
      /^common/,/^[[:alpha:]]/ {
        s/^(\s+<<:).*/\1 *'$DIASPORA_DOCKER_DB'/
      }' "$DIASPORA_CONFIG_DB".example > "$DIASPORA_CONFIG_DB"
  fi
  # Update exisiting database.yml to reflect correct database type
  if [ "$(dia_get_db)" != "$DIASPORA_DOCKER_DB" ]; then
    sed -E -i'' '
      /^common/,/^[[:alpha:]]/ {
        s/^(\s+<<:).*/\1 *'$DIASPORA_DOCKER_DB'/
      }' "$DIASPORA_CONFIG_DB"
  fi
}

dia_cucumber() {
  # Run cucumber tests
  if [ "$1" == "-d" ]; then detach="-d"; shift; fi
  dia_docker_compose run \
    --rm $detach \
    diaspora \
    bin/cucumber "$@"
}

dia_exec() {
  # Run a custom command inside a running diaspora container. Start a new one if necessary.
  exit_if_unconfigured
  if [ "$1" == "-d" ]; then detach="-d"; shift; fi
  if dia_is_running; then
    # Use a running container
    dia_docker_compose exec $detach diaspora /exec-entrypoint.sh "$@"
  else
    if ! dia_is_db_running; then not_running=1; fi
    # Start a new container
    echo "No running instance found, starting new one for command execution ..."
    dia_docker_compose run --rm $detach --service-ports diaspora "$@"
    if [ ! -z $not_running ]; then
      dia_docker_compose stop $DIASPORA_DOCKER_DB
    fi
  fi
}

dia_jasmine() {
  # Run jasmine tests
  dia_docker_compose run \
    --rm $1 \
    -e RAILS_ENV=test \
    diaspora \
    bin/rake jasmine:ci
}

dia_logs() {
  # Show logs of running diaspora* instance
  dia_follow=diaspora
  for i in "$@"; do
    case "$i" in
      -a|--all)
        dia_follow=""
        ;;
    esac
  done
  dia_docker_compose logs -f --tail=100 $dia_follow
}

dia_migrate() {
  # Run migrations if configured
  echo "Creating and/or migrating database ..."
  exit_if_unconfigured
  dia_docker_compose run \
    --rm $1 \
    diaspora \
    bin/rake db:create db:migrate
}

dia_pronto() {
  # Run pronto checks
  exit_if_unconfigured
  cd "$DIASPORA_ROOT"
  if git diff-index --quiet HEAD --; then
    dia_fetch_upstream
  fi
  cd - >/dev/null
  dia_docker_compose run \
    --rm \
    --no-deps \
    diaspora \
    bin/pronto run --unstaged -c upstream/develop
}

dia_restart() {
  # Restart diaspora inside container if already running; start new container otherwise
  for i in "$@"; do
    case "$i" in
      --full)
        dia_restart_full=1
        ;;
    esac
  done
  if dia_is_running; then
    if [ -z $dia_restart_full ]; then
      dia_docker_compose exec \
        diaspora \
        bin/eye restart diaspora
    else
      dia_docker_compose restart
    fi
  else
    dia_start
  fi
}

dia_rspec() {
  # Run rspec tests
  exit_if_unconfigured
  assets=""
  # Assumption: If (and only if) the tested file is not available, assets need be regenerated
  [ -f "$DIASPORA_ROOT"/public/404.html ] && assets="assets:generate_error_pages"
  # Prepare database (and assets if necessary)
  dia_docker_compose run \
    --rm \
    -e RAILS_ENV=test \
    diaspora \
    bin/rake db:create db:migrate $assets
  # Run tests
  dia_docker_compose run \
    --rm \
    diaspora \
    bin/rspec "$@"
}

dia_setup() {
  # Prepare the entire environment for development
  for i in "$@"; do
    case "$i" in
      --force)
        build="$build --no-cache"
        config="$config --overwrite"
        ;;
      --mysql)
        config="$config --mysql"
        ;;
    esac
  done
  (
    set -e
    dia_build $build
    dia_config $config
    dia_bundle $bundle
    dia_migrate $migrate
    dia_setup_tests $setup_tests
  )
  # stop db afterwards as it is not needed while dia is not running
  dia_docker_compose stop $DIASPORA_DOCKER_DB
}

dia_setup_tests() {
  # Prepare all possible tests
  # stop db if it was not running before
  echo "Setting up environment for tests ..."
  if ! dia_is_db_running; then stopdb="dia_docker_compose stop $DIASPORA_DOCKER_DB"; fi
  dia_docker_compose run \
    --rm \
    -e RAILS_ENV=test \
    diaspora \
    bin/rake db:create db:migrate tests:generate_fixtures assets:generate_error_pages
  $stopdb
}

dia_start() {
  # Start all containers if config appears to exist
  exit_if_unconfigured
  if [ $# -eq 0 ]; then
    options=--abort-on-container-exit
  else
    options=$1
  fi
  dia_docker_compose up $options diaspora
}

dia_status() {
  # Print running containers and current images
  dia_docker_compose ps
  echo
  dia_docker_compose images
}

dia_stop() {
  # Stop all containers
  dia_docker_compose stop
}


# ----- Variables -----
# Symlinks are treated as files
export SCRIPT_NAME=$(basename "${BASH_SOURCE[0]}")
export SCRIPT_ROOT=$(cd $(dirname "${BASH_SOURCE[0]}") && pwd)

# Assumption: The script is in the "script" subfolder of the diaspora root folder
export DIASPORA_ROOT=$(dirname "$SCRIPT_ROOT")
export DIASPORA_ROOT_UID=1001
export DIASPORA_ROOT_GID=1001
export DIASPORA_CONFIG_DIA=$DIASPORA_ROOT/config/diaspora.toml
export DIASPORA_CONFIG_DB=$DIASPORA_ROOT/config/database.yml
export DIASPORA_DOCKER_DB=$(dia_get_db)

export COMPOSE_FILE=$DIASPORA_ROOT/docker/develop/docker-compose.yml
export COMPOSE_PROJECT_NAME=diasporadev

# ----- Arg parsing -----
if [ $# -lt 1 ]; then
  print_usage
  exit 1
fi

dia_command=$1
shift

case "$dia_command" in
  --help|-h)
    print_usage_full
    exit 0
    ;;
  help)
    if [ $# -lt 1 ]; then
      print_usage_full
    else
      print_usage "$1"
    fi
    exit 0
    ;;
  build)
    dia_build "$@"
    ;;
  bundle)
    dia_bundle "$1"
    ;;
  clean)
    dia_clean "$@"
    ;;
  config)
    dia_config "$@"
    ;;
  cucumber)
    dia_cucumber "$@"
    ;;
  exec)
    dia_exec "$@"
    ;;
  jasmine)
    dia_jasmine
    ;;
  logs)
    dia_logs "$@"
    ;;
  migrate)
    dia_migrate "$@"
    ;;
  pronto)
    dia_pronto
    ;;
  restart)
    dia_restart "$@"
    ;;
  rspec)
    dia_rspec "$@"
    ;;
  setup)
    dia_setup "$@"
    ;;
  setup-tests)
    dia_setup_tests
    ;;
  start)
    dia_start "$1"
    ;;
  status)
    dia_status
    ;;
  stop)
    dia_stop
    ;;
  *)
    print_usage
    exit 1
    ;;
esac