#!/usr/bin/env bash

## CONSTANTS

REPO_BRANCH=main
YAMAL_DIR=/home/yamal
YAMAL_CONFIG=$YAMAL_DIR/config
RAILS_BASE_PORT=900
FORCE=false
DEBUG=''

PACMAN_CMD='pacman'
SESSION_RESTART=false
OS_RELEASE=/etc/os-release
DISTRO=$(test -f "$OS_RELEASE" && (grep -s ^ID "$OS_RELEASE" | cut -d= -f2) || echo unknown_distro)

# TODO: project introspection...
declare -A DISTRO_PACKAGES
DISTRO_PACKAGES[_]="postgresql shfmt"
DISTRO_PACKAGES[debian]="build-essential libssl-dev libyaml-dev zlib1g-dev libgmp-dev libpq-dev libvips42 poppler-utils redis-server"
DISTRO_PACKAGES[arch]="base-devel openssl libyaml zlib gmp libvips poppler valkey"

## FUNCTIONS

function usage {
  echo "$(dirname $0)/$(basename $0) --repo-url|-r <URL> [--repo-name|-n <NAME>] [--project|-p <NAME>] [--branch|-b <BRANCH>] [--force|-f] [--debug|-d]"
}

function assert_requirements {
  [[ ! $SHELL =~ /bash$ ]] && (echo 'bash is mandatory!' && exit 1)
  command -v curl >/dev/null || (echo 'curl is mandatory!' && exit 2)
  true
}

function parse_options {
  while [[ $# -gt 0 ]]; do
    case "$1" in
    --repo-url | -r)
      shift 1
      [[ -z ${1:-} || $1 =~ ^- ]] && usage && exit 1
      REPO_URL=$1
      ;;    	
    --repo-name | -n)
      shift 1
      [[ -z ${1:-} || $1 =~ ^- ]] && usage && exit 1
      REPO_NAME=$1
      ;;    	
    --project | -p)
      shift 1
      [[ -z ${1:-} || $1 =~ ^- ]] && usage && exit 1
      PROJECT_NAME=$1
      ;;
    --branch | -b)
      shift 1
      [[ -z ${1:-} || $1 =~ ^- ]] && usage && exit 1
      REPO_BRANCH=$1
      ;;
    --origin | -o)
      shift 1
      [[ -z ${1:-} || $1 =~ ^- ]] && usage && exit 1
      ORIGIN=$1
      ;;
    --force | -f)
      FORCE=true
      ;;
    --debug | -d)
      DEBUG='bash -xl'
      ;;
    --help | -h)
      usage
      exit 0
      ;;
    *)
      echo "Unknown option: $1"
      usage
      exit 2
      ;;
    esac

    shift 1 # Move to the next argument
  done
}

function assert_repo_url {
	if [[ -z ${REPO_URL:-} ]]; then
		>&2 echo -e "ERROR3: REPO_URL undefined!\n\tplease either use --repo-url or -r\n"
		usage
		exit 3
	fi
}

function create_user {
  if ! id -u $PROJECT_NAME >/dev/null 2>&1; then
    [[ -d /opt/$PROJECT_NAME ]] &&
      echo -e "ERROR\n special opt folder not empty: /opt/$PROJECT_NAME\nplease specify unique project name with argument --project|-p" &&
      exit 20
    sudo -u yamal -- mkdir -p $YAMAL_DIR/projects
    useradd -G ssh,yamal -rm --home-dir $YAMAL_DIR/projects/$PROJECT_NAME --shell /bin/bash $PROJECT_NAME
    echo "user $PROJECT_NAME successfully created!"
  fi

  if [[ ! -d /opt/$PROJECT_NAME ]]; then
    mkdir -p /opt/$PROJECT_NAME
    chown $PROJECT_NAME:$PROJECT_NAME /opt/$PROJECT_NAME
  fi

  if [[ ! -d /etc/$PROJECT_NAME ]]; then
    mkdir -p /etc/$PROJECT_NAME
    echo "special folder: /etc/$PROJECT_NAME successfully created!"
  fi
  chown -R $PROJECT_NAME:$PROJECT_NAME /etc/$PROJECT_NAME
}

function set_project_name {
	[[ -z ${REPO_NAME:-} ]] && REPO_NAME=$(echo $REPO_URL | rev | cut -d/ -f1 | rev |cut -d. -f1) # get last url part minus '.git'
	DB_USER=$REPO_NAME
	[[ -z ${PROJECT_NAME:-} ]] && PROJECT_NAME=$REPO_NAME
	true
}

function define_rails_app {
  if [[ -f $YAMAL_CONFIG ]]; then
    local index=$(grep "^rails_app_.*=$PROJECT_NAME\$" $YAMAL_CONFIG | cut -d '=' -f1 | cut -d '_' -f3)
    [[ -z $index ]] && index=$(grep "rails_app_count=" $YAMAL_CONFIG | cut -d '=' -f2)
  fi
  RAILS_APP=${index:-0}
}

function inc_rails_app_count {
  if [[ -f $YAMAL_CONFIG ]]; then
    if ! grep -q "^rails_app_.*=$PROJECT_NAME\$" $YAMAL_CONFIG; then
      echo "rails_app_$RAILS_APP=$PROJECT_NAME" >>$YAMAL_CONFIG
      RAILS_APP=$(($RAILS_APP + 1))
      sed -i "s/^rails_app_count.*/rails_app_count=$RAILS_APP/" $YAMAL_CONFIG
      echo "new rails app succesfully registered!"
    fi
  else
    mkdir -p $(dirname $YAMAL_CONFIG)
    echo "rails_app_count=1" >$YAMAL_CONFIG
    echo "rails_app_$RAILS_APP=$PROJECT_NAME" >>$YAMAL_CONFIG
  fi
}

function install_systemd_service {
  local service="/etc/systemd/system/$PROJECT_NAME.service"
  local rails_port=$(($RAILS_BASE_PORT + $RAILS_APP))
  if [[ ! -f $service ]]; then
    cat <<EOF >$service
[Unit]
Description=$PROJECT_NAME
After=network.target

[Service]
Type=simple
User=$PROJECT_NAME
SyslogIdentifier=$PROJECT_NAME
AmbientCapabilities=CAP_NET_BIND_SERVICE
PermissionsStartOnly=true
WorkingDirectory=/opt/$PROJECT_NAME
ExecStart=$YAMAL_DIR/projects/$PROJECT_NAME/.local/bin/mise exec -- rails server --port $rails_port

[Install]
WantedBy=multi-user.target
EOF
    systemctl daemon-reload
    systemctl enable $PROJECT_NAME
  fi
  systemctl restart $PROJECT_NAME
  systemctl is-active $PROJECT_NAME >/dev/null && echo "service $PROJECT_NAME running on port: $rails_port"
}

function launch_normal_user_setup {
  # clean temporary files in case mise install ruby fails!
  rm /tmp/mise-ruby-build -rf

  echo "launch setup as normal user: $PROJECT_NAME"
  local cmd="${DEBUG:-bash -l} -- $(realpath $(dirname "$0"))/lib/setup-prod-normal-user.bash $REPO_URL $REPO_BRANCH $FORCE"
  if sudo -iu $PROJECT_NAME $cmd; then
    : #ok
  else
    local exit_code=$?
    [[ $exit_code == 100 ]] && echo 'up-to-date: no change!' && exit 0
    echo "an error $exit_code has occured during 'setup-prod-normal-user'" && exit $exit_code
  fi
}

function enhance_mise_user_from_origin {
  [[ -z ${ORIGIN:-} ]] && return
  if [[ -d $ORIGIN/.local/share/mise/installs/ruby ]] && [[ ! -f /home/$PROJECT_NAME/.local/bin/mise ]]; then
    echo -n "copy mise ruby from origin=$ORIGIN..."
    mkdir -p /home/$PROJECT_NAME/.local/share/mise/installs/ruby
    cp -r $ORIGIN/.local/share/mise/installs/ruby /home/$PROJECT_NAME/.local/share/mise/installs/
    chown -R $PROJECT_NAME:$PROJECT_NAME /home/$PROJECT_NAME/.local
    echo OK
  fi
}

function install_pacapt {
  if [[ ! -f $HOME/.local/bin/pacman ]]; then
    mkdir -p $HOME/.local/bin
    curl -sLo $HOME/.local/bin/pacman https://github.com/icy/pacapt/raw/ng/pacapt
    chmod 755 $HOME/.local/bin/pacman
  else
    if [[ $DISTRO == 'arch' ]]; then
      echo 'pacman natively detected!'
    else
      PACMAN_CMD="$HOME/.local/bin/pacman"
      # echo "pacapt/pacman ($PACMAN_CMD) already installed!"
    fi
  fi
}

function install_idem_packages {
  if ! pacman -Qi $1 &>/dev/null; then
    sudo $HOME/.local/bin/pacman -S --noconfirm $1 >/dev/null
    echo "$2 installed successfully"
  else
    echo "$2 already installed!"
  fi
}

function install_packages {
  install_idem_packages "${DISTRO_PACKAGES[_]}" "generic packages"
  [ -v "DISTRO_PACKAGES[${DISTRO}]" ] && install_idem_packages "${DISTRO_PACKAGES[${DISTRO}]}" "distro specific packages: [$DISTRO]"
  true
}

function assert_etc_config_for_user {
  local config_dir="/etc/$PROJECT_NAME"
  if [[ -d $config_dir ]]; then
    chown $PROJECT_NAME $config_dir
    chmod -R 750 $config_dir
  else
    echo -e "-----\nERROR\n-----\nplease provide configuration file from location:\n     $config_dir"
    false
  fi
}

function postgres_newdb {
  if ! (sudo -u postgres -- psql --csv -tc "SELECT 1 as found FROM pg_roles WHERE rolname = '$DB_USER'" | grep -q ^1$); then
  	echo "creating postgresql user: $DB_USER"
    sudo -iu postgres psql -c "CREATE USER $DB_USER WITH PASSWORD '$DB_USER'"
    sudo -iu postgres psql -c "ALTER USER $DB_USER WITH SUPERUSER"
  fi
}

function postgres_global_encoding_utf8 {
  if ! sudo -iu postgres -- psql -c '\l template1' | grep -q UTF8; then
  	echo 'defining postgresql template1 with default UTF8 encoding'
  	sudo -iu postgres -- psql <<EOF
UPDATE pg_database SET datistemplate = FALSE WHERE datname = 'template1';
DROP DATABASE template1;
CREATE DATABASE template1 WITH TEMPLATE = template0 ENCODING = 'UTF8';
UPDATE pg_database SET datistemplate = TRUE WHERE datname = 'template1';
VACUUM FREEZE;
EOF
  fi
}

## MAIN

assert_requirements
parse_options $*

[[ $(id -u) != 0 ]] && exec sudo -- $DEBUG $(dirname "$0")/$(basename "$0") --origin $HOME $*

set -Eue

assert_repo_url
set_project_name
install_pacapt
install_packages
define_rails_app

# echo "$PROJECT_NAME:$REPO_BRANCH:$RAILS_APP:$ORIGIN"

create_user
assert_etc_config_for_user
# enhance_mise_user_from_origin # FIXME: not working yet!
postgres_global_encoding_utf8
postgres_newdb
launch_normal_user_setup
install_systemd_service
inc_rails_app_count