#!/bin/bash

### CONSTANTS ###
START_PORT_RANGE=30000
BASE_DIR=~/"Mordhau"
CONFIG_DIRECTORY="${BASE_DIR}/config"
MODS_CONFIG="${CONFIG_DIRECTORY}/mods.conf"
ADMINS_CONFIG="${CONFIG_DIRECTORY}/admins.conf"
RCON_PASS_LOCATION="${CONFIG_DIRECTORY}/rcon.pass"
SERVER_PASS_LOCATION="${CONFIG_DIRECTORY}/server.pass"
### CONSTANTS ###

echo_rgb() {
  # Echo a colored string to the terminal based on rgb values
  #
  # Positional Arguments:
  #
  #   message <type: string> <position: 1> <required: true>
  #     - The message to be printed to stdout
  #   red <type: int> <position: 2> <required: true>
  #     - The red value from 0 to 255
  #   green <type: int> <position: 3> <required: true>
  #     - The green value from 0 to 255
  #   blue <type: int> <position: 4> <required: true>
  #     - The blue value from 0 to 255
  #
  # Usage:
  #   echo_rgb "Yep" 10 8 30
  #
  # POSIX Compliant:
  #   N/A
  #

  local red
  local green
  local blue
  local input

  input="${1}"
  red="${2}"
  green="${3}"
  blue="${4}"

  printf "\e[0;38;2;%s;%s;%sm%s\e[m\n" "${red}" "${green}" "${blue}" "${input}"
}

log() {
  # Print a message and send it to stdout or stderr depending upon log level, also configurable with debug etc.
  #
  # Arguments:
  #   level <type: string> <position: 1> <required: true>
  #     - The log level, defined within a case check in this function
  #   message <type: string> <position: 2> <required: true>
  #     - The info message
  #   line_number <type: int> <position: 3> <required: false>
  #     - The line number of the calling function (${LINNO})
  #
  # Usage:
  #   log "info" "Could not find that directory"
  #
  # POSIX Compliant:
  #   Yes
  #

  # Set debug status depending if a global debug variable has been set to either 1 or 0
  local debug
  if [ ${DEBUG} ]; then
    debug=${DEBUG}
  else
    debug=0
  fi

  local FORMAT
  FORMAT="[$(echo_rgb "$(date +%Y-%m-%dT%H:%M:%S)" 180 140 255)]"

  # Convert the level to uppercase
  local level
  level=$(echo "${1}" | tr '[:lower:]' '[:upper:]')

  local message
  message="${2}"

  case "${level}" in
  INFO)
    # Output all info log levels to stdout
    printf "${FORMAT}[$(echo_rgb "INFO" 0 140 255)] %s\n" "${message}" >&1
    return 0
    ;;
  WARN | WARNING)
    # Output all info log levels to stdout
    printf "${FORMAT}[$(echo_rgb "WARNING" 255 255 0)] %s\n" "${message}" >&1
    return 0
    ;;
  DEBUG)
    [[ ${debug} == 0 ]] && return
    printf "${FORMAT}[$(echo_rgb "DEBUG" 0 160 110)] %s\n" "${message}" >&1
    return 0
    ;;
  ERROR)
    # Output all error log levels to stderr
    printf "${FORMAT}[$(echo_rgb "ERROR" 255 0 0)] %s\n" "${message}" >&2
    return 0
    ;;
  # Further log levels can be added by extending this switch statement with more comparisons

  *) # Default case, no matches
    # Returns non-zero code as an improper log option was passed, this helps with using `set -e`
    printf "${FORMAT}[ERROR] %s\n" "Invalid log level passed, received level \"${level}\" with message \"${message}\"" >&2
    return 1
    ;;
  esac
}

confirmation() {
  # Receive confirmation from user as y, Y, n, or N
  # returns 0 when answer is yes and 1 when answer is no
  #
  # Arguments:
  #   message <type: string> <position: 1> <required: true>
  #     - The confirmation prompt sent to the user, for example:
  #       Would you like to overwrite foobar.txt (y/N)?
  #
  # Usage:
  #   confirmation "Some prompt"
  #     - Sends "Some prompt" to the user and gets their input
  #
  # POSIX Compliant:
  #   Yes
  #

  local message
  message="${1}"

  local choice

  while true; do
    read -p "${message} " -n 1 -r choice
    case "$choice" in
    y | Y)
      echo ""
      return 0
      ;;
    n | N)
      echo ""
      return 1
      ;;
    *) echo -e "\nInput must be either y, Y, n, or N" ;;
    esac
  done
}

important() {
  echo_rgb "${1}" 135 195 255
}

kill_server() {
  local prefix
  local tmux_response
  local server_id

  server_id=""
  prefix="Mordhau"

  while :; do
    case ${1} in
    -h | -\? | --help)
      printf "Usage: %s\n" \
        "kill --server <server id: int> | kill -s <server id: int>
  --server <server id: int> | -s <server id: int>
    Kills the server with the given id

    Example:
      --server 3"
      exit
      ;;
    --) # End of all options.
      break
      ;;
    --server | -s)
      shift
      server_id="${1}"
      [[ -z "${server_id}" ]] && log "error" "No server id passed" && exit 1
      ;;
    -?*)
      printf 'Unknown option: %s\n' "$1" >&2
      ;;
    *) # Default case: No more options, so break out of the loop.
      break ;;
    esac
    shift
  done

  [[ -z "${server_id}" ]] && log "error" "No server id passed" && exit 1

  tmux kill-session -t "${prefix}-Server-${server_id}" >/dev/null 2>&1
  tmux_response="${?}"

  if [ "${tmux_response}" == "0" ]; then
    log "info" "Stopped $(important "${prefix}-Server-${server_id}")"
    return "${tmux_response}"
  else
    log "error" "Could not find $(important "${prefix}-Server-${server_id}") or unable to shut down ${prefix}-Server-${server_id}"
    return "${tmux_response}"
  fi
}

should_kill() {
  local prefix
  local server_id

  prefix="Mordhau"
  server_id="${1}"

  tmux has-session -t "${prefix}-Server-${server_id}" >/dev/null 2>&1

  if [ "${?}" == 0 ]; then
    log "warning" "${prefix} server $(important "${prefix}-Server-${server_id}") is currently running"

    confirmation "Would you like to kill it (y/N)?"

    if [[ "${?}" -eq 0 ]]; then
      log "info" "Ok, killing server $(important "${prefix}-Server-${server_id}")"
      tmux kill-session -t "${prefix}-Server-${server_id}" &&
        log "info" "Successfully killed $(important "${prefix}-Server-${server_id}")"
      return 0
    else
      log "info" "Not ending current server $(important "${prefix}-Server-${server_id}"), exiting..."
      return 1
    fi
  fi

  return 0
}

run_and_kill() {
  local prefix
  local server_id

  prefix="Mordhau"
  server_id="${1}"

  local server_directory
  server_directory="${BASE_DIR}/Server-${server_id}"

  log "info" "Launching ${prefix}-Server-${server_id} to install any missing configurations..."

  tmux new-session -d -s "${prefix}-Server-${server_id}" \
    "${server_directory}/MordhauServer.sh"

  sleep 5

  tmux kill-session -t "${prefix}-Server-${server_id}" &&
    log "info" "Successfully ran the Mordhau session and stopped the session"

  return 0
}

generate_default_configs() {

  mkdir -p "${BASE_DIR}" && log "info" "Created base directory if it didn't exist"
  mkdir -p "${CONFIG_DIRECTORY}" && log "info" "Created config directory if it didn't exist"

  if [ ! -f "${RCON_PASS_LOCATION}" ]; then
    local rcon_pass
    rcon_pass="$(openssl rand -base64 48)"
    echo "${rcon_pass}" >"${RCON_PASS_LOCATION}"
    log "info" "Generated a new rcon password as it did not exist"
  fi

  if [ ! -f "${SERVER_PASS_LOCATION}" ]; then
    echo "20rserver" >"${SERVER_PASS_LOCATION}"
    log "info" "Generated the server password file as it did not exist"
  fi

  if [ ! -f "${MODS_CONFIG}" ]; then

    cat <<__EOF__ >"${MODS_CONFIG}"
# This is the default mods configuration file
# To define mods use the following syntax: Mods=mod_id
# For example:
# Mods=1121745
__EOF__
    log "info" "Created a new mods configuration with no mods at ${MODS_CONFIG}"
  fi

  if [ ! -f "${ADMINS_CONFIG}" ]; then

    cat <<__EOF__ >"${ADMINS_CONFIG}"
# This is the default admins configuration file
# To define admins use the following syntax: Admins=PLAYFAB_ID
# For example:
# Admins=5E92E0B55E90869C
__EOF__
    log "info" "Created a new admins configurations with no admins at ${ADMINS_CONFIG}"
  fi

  log "info" "Generated all configs if they did not exist"
}

configure() {

  local server_id
  local list
  local verbose
  local edit

  server_id=""
  list=0
  verbose=0
  edit=0

  while :; do
    case ${1} in
    -h | -\? | --help)
      printf "Usage: %s\n" \
        "configure [options]
  --server <server id: int> | -s <server id: int>
    Lists the path to the Game-Primary.ini for the given server, useful for cat and other scripting. Required if --list not passed
    
    Example:
      --server 3
    
  --list | -l
    List all paths to the Game-Primary.ini configs for all servers, very useful for cat and other scripting. Required if --server not passed
  
    Example:
      --list
  
  --edit | -e
    Opens each Game-Primary.ini in nano
    
    Example:
      --edit
    
  --verbose | -v
    Shows further output -- useful for a glance, should not be used with scripts
    
    Example:
      --verbose"
      exit
      ;;
    --) # End of all options.
      break
      ;;
    --server | -s)
      shift
      server_id="${1}"
      [[ -z "${server_id}" ]] && log "error" "No server id passed" && exit 1
      ;;
    --list | -l)
      list=1
      ;;
    --verbose | -v)
      verbose=1
      ;;
    --edit | -e)
      edit=1
      ;;
    -?*)
      printf 'Unknown option: %s\n' "$1" >&2
      ;;
    *) # Default case: No more options, so break out of the loop.
      break ;;
    esac
    shift
  done

  display_verbose_output() {
    # First argument is the server number
    echo "$(important "Server-${1}") ($(important "Mordhau-Server-${1}"))"
    echo "=================================="
  }
  if [ -z "${server_id}" ] && [ "${list}" -eq 0 ]; then
    log "error" "Neither list nor server option passed, check configure --help"
    exit 1
  fi

  if [ -n "${server_id}" ]; then
    local server_directory
    local primary_server_config
    server_directory="${BASE_DIR}/Server-${server_id}"
    server_num="${server_id}"
    primary_server_config="${server_directory}/Mordhau/Saved/Config/LinuxServer/Game-Primary.ini"

    [[ ! -f "${primary_server_config}" ]] &&
      log "error" "Unable to find a config for $(important "Server-${server_num}") (${primary_server_config})" &&
      exit 1
    if [ "${verbose}" -eq 1 ]; then
      display_verbose_output "${server_num}"
    fi
    echo "${primary_server_config}"
    if [[ "${edit}" -eq 1 ]]; then
      log "info" "Editing $(important "Server-${server_num}")'s config located at ${primary_server_config}..."
      nano "${primary_server_config}"
    fi
  fi

  if [[ "${list}" -eq 1 ]]; then
    for server in "${BASE_DIR}/Server-"*; do
      local server_directory
      local primary_server_config
      server_directory="${server}"
      server_num="${server: -1}"
      primary_server_config="${server_directory}/Mordhau/Saved/Config/LinuxServer/Game-Primary.ini"

      [[ ! -f "${primary_server_config}" ]] &&
        log "error" "Unable to find a config for $(important "Server-${server_num}") (${primary_server_config})" &&
        continue

      if [[ "${verbose}" -eq 1 ]]; then
        echo ""
        display_verbose_output "${server_num}"
      fi
      echo "${primary_server_config}"
      if [[ "${edit}" -eq 1 ]]; then
        log "info" "Editing $(important "Server-${server_num}")'s config located at ${primary_server_config}..."
        sleep 2
        nano "${primary_server_config}"
      fi
    done
  fi
}

start() {
  local server_id
  local can_kill

  server_id=""
  can_kill=0

  while :; do
    case ${1} in
    -h | -\? | --help)
      printf "Usage: %s\n" \
        "start --server <server id: int> | kill -s <server id: int>
  --server <server id: int> | -s <server id: int>
    Starts the given server id

    Example:
      --server 3
  --can-kill | -c
    Automatically kills the server if it is running without prompting

    Example:
      --can-kill"
      exit
      ;;
    --) # End of all options.
      break
      ;;
    --server | -s)
      shift
      server_id="${1}"
      [[ -z "${server_id}" ]] && log "error" "No server id passed" && exit 1
      ;;
    --can-kill | -c)
      can_kill=1
      ;;
    -?*)
      printf 'Unknown option: %s\n' "$1" >&2
      ;;
    *) # Default case: No more options, so break out of the loop.
      break ;;
    esac
    shift
  done

  generate_default_configs

  [[ -z "${server_id}" ]] && log "error" "No server id passed" && exit 1

  local server_directory
  local server_config
  server_directory="${BASE_DIR}/Server-${server_id}"
  server_config_directory="${server_directory}/Mordhau/Saved/Config/LinuxServer"
  server_config="${server_config_directory}/Game.ini"

  [[ ! -d "${server_directory}" ]] &&
    log "error" "Unable to find the server directory for ${server_id}, verify the server exists at ${server_directory}" &&
    exit 1

  [[ ! -f "${server_config}" ]] &&
    log "error" "Unable to find a valid Game.ini for Server-${server_id}, verify the installation is correct" &&
    exit 1

  local rcon_pass
  local server_pass
  local mods
  local admins

  rcon_pass="$(cat "${RCON_PASS_LOCATION}")"
  server_pass="$(cat "${SERVER_PASS_LOCATION}")"

  if [[ "${can_kill}" -eq "1" ]]; then
    kill_server -s "${server_id}" >/dev/null 2>&1
  else
    should_kill "${server_id}"
    [[ "${?}" == "1" ]] && exit 1
  fi

  while read -r line; do
    if [[ "${line}" == "#"* ]]; then
      :
    else
      echo "${line}"
    fi
  done <"${MODS_CONFIG}" >"${BASE_DIR}/mods.tmp"

  mods="$(cat "${BASE_DIR}/mods.tmp")"
  rm -f "${BASE_DIR}/mods.tmp"

  while read -r line; do
    if [[ "${line}" == "#"* ]]; then
      :
    else
      echo "${line}"
    fi
  done <"${ADMINS_CONFIG}" >"${BASE_DIR}/admins.tmp"

  admins="$(cat "${BASE_DIR}/admins.tmp")"
  rm -f "${BASE_DIR}/admins.tmp"

  local game_port
  local query_port
  local beacon_port
  local rcon_port

  game_port=$(("${START_PORT_RANGE}" + $(("${server_id}" * 4)) + 0))
  query_port=$(("${START_PORT_RANGE}" + $(("${server_id}" * 4)) + 1))
  beacon_port=$(("${START_PORT_RANGE}" + $(("${server_id}" * 4)) + 2))
  rcon_port=$(("${START_PORT_RANGE}" + $(("${server_id}" * 4)) + 3))

  log "info" "Updating Game-Primary.ini"
  local backup_extension
  backup_extension="$(date +%Y-%m-%dT%H:%M:%S%z)"

  # Necessary as the external config to Game.ini
  local game_primary
  game_primary="${server_config_directory}/Game-Primary.ini"

  [[ ! -f "${game_primary}" ]] &&
    cp "${server_config}" "${game_primary}" &&
    log "info" "Created a Game-Primary.ini config as it did not exist"

  log "info" "Creating Game-Primary.ini backup as Game-Primary.ini.${backup_extension}"
  cp "${game_primary}" "${game_primary}.${backup_extension}"
  log "info" "Created backup of Game-Primary.ini located at ${game_primary}.${backup_extension}"

  # The below booleans are used to avoid duplicating lines, a sort of failsafe
  local updated_rcon_port
  local updated_rcon_pass

  updated_rcon_port=0
  updated_rcon_pass=0

  # Loading primary config bool is incredibly important as it controls loading the external configurations to the server
  local primary_config_admins_mods
  local loading_primary_config
  local loaded_primary_config
  loading_primary_config=0
  loaded_primary_config=0

  primary_config_admins_mods="$(
    cat <<__EOF__
# BEGIN PRIMARY CONFIG - DO NOT INCLUDE SERVER SPECIFIC CONFIGURATION BETWEEN THIS LINE AND "END PRIMARY CONFIG"
# Primary config Mods
${mods}

# Primary config Admins
${admins}
# END PRIMARY CONFIG - DO NOT INCLUDE SERVER SPECIFIC CONFIGURATION BETWEEN THIS LINE AND "BEGIN PRIMARY CONFIG"
__EOF__
  )"

  log "info" "Overwriting Game.ini..."

  while read -r line; do
    if [[ "${line}" == "RconPort="* ]] && [ "${updated_rcon_port}" -eq 0 ]; then
      echo "RconPort=${rcon_port}"
      updated_rcon_port=1
    elif [[ "${line}" == "RconPassword="* ]] && [ "${updated_rcon_pass}" -eq 0 ]; then
      echo "RconPassword=${rcon_pass}"
      updated_rcon_pass=1
    elif [[ "${line}" == *"BEGIN PRIMARY CONFIG"* ]]; then
      loading_primary_config=1
    elif [[ "${line}" == *"END PRIMARY CONFIG"* ]]; then
      loading_primary_config=0
      echo "${primary_config_admins_mods}"
      loaded_primary_config=1
    elif [ "${loading_primary_config}" -eq 0 ]; then
      echo "${line}"
    fi
  done <"${game_primary}" >"serv.temp"

  if [ "${loaded_primary_config}" -eq 0 ]; then
    log "info" "Primary config not injected, loading it now..."
    echo "${primary_config_admins_mods}" >>"serv.temp"
    log "info" "Successfully injected primary config"
  fi

  mv "serv.temp" "${game_primary}"
  cat "${game_primary}" >"${server_config}"

  log "info" "Finished updating Game-Primary.ini ($(important "${game_primary}"))"

  log "info" "Ports:
  $(important "   Game Port: ${game_port}")
  $(important "   Query Port: ${query_port}")
  $(important "   Beacon Port: ${beacon_port}")
  $(important "   RCON Port: ${rcon_port}")"
  log "info" "Startup Arguments:
  $(important "   -Port=${game_port}")
  $(important "   -QueryPort=${query_port}")
  $(important "   -BeaconPort=${beacon_port}")
  $(important "   -LOG")
  $(important "   -USEALLAVAILABLE")"

  tmux new-session -d -s "Mordhau-Server-${server_id}" \
    ${BASE_DIR}/Server-"${server_id}"/MordhauServer.sh \
    -Port="${game_port}" \
    -QueryPort="${query_port}" \
    -BeaconPort="${beacon_port}" \
    -LOG \
    -USEALLAVAILABLE &&
    log "info" "Successfully started Mordhau-Server-${server_id}"

}

update() {
  local server_id
  local redownload_mods

  server_id=""
  redownload_mods=0

  while :; do
    case ${1} in
    -h | -\? | --help)
      printf "Usage: %s\n" \
        "update --server <server id: int> | kill -s <server id: int>
  --server <server id: int> | -s <server id: int>
    Starts the given server id

    Example:
      --server 3
  --redownload-mods | -r
    Redownloads all mods by clearing the .modio folder"
      exit
      ;;
    --) # End of all options.
      break
      ;;
    --server | -s)
      shift
      server_id="${1}"
      [[ -z "${server_id}" ]] && log "error" "No server id passed" && exit 1
      ;;
    -?*)
      printf 'Unknown option: %s\n' "$1" >&2
      ;;
    *) # Default case: No more options, so break out of the loop.
      break ;;
    esac
    shift
  done

  [[ -z "${server_id}" ]] && log "error" "No server id passed" && exit 1

  kill_server -s "${server_id}" >/dev/null 2>&1

  local server_directory
  local server_config
  server_directory="${BASE_DIR}/Server-${server_id}"
  server_config="${server_directory}/Mordhau/Saved/Config/LinuxServer/Game.ini"

  [[ ! -d "${server_directory}" ]] &&
    log "error" "No server directory found for ${server_id}, checked at ${server_directory}" &&
    exit 1

  if [ "${redownload_mods}" == "1" ]; then
    rm -rf "${server_directory}/Mordhau/Content/.modio"
    log "info" ".modio cleared, start Server-${server_id} to download mods"
  fi

  log "info" "Verifying and updating server"
  steamcmd +login anonymous +force_install_dir "${server_directory}" +app_update 629800 validate +quit
  run_and_kill "${server_id}"
  log "info" "Successfully verified and updated $(important "Server-${server_id}")"

}

install() {

  local server_id
  server_id=""

  while :; do
    case ${1} in
    -h | -\? | --help)
      printf "Usage: %s\n" \
        "install --server <server id: int> | install -s <server id: int>
  --server <server id: int> | -s <server id: int>
    Installs the server to the given id if it doesn't exist

    Example:
      --server 3"
      exit
      ;;
    --) # End of all options.
      break
      ;;
    --server | -s)
      shift
      server_id="${1}"
      [[ -z "${server_id}" ]] && log "error" "No server id passed" && exit 1
      ;;
    -?*)
      printf 'Unknown option: %s\n' "$1" >&2
      ;;
    *) # Default case: No more options, so break out of the loop.
      break ;;
    esac
    shift
  done

  [[ -z "${server_id}" ]] && log "error" "No server id passed" && exit 1

  local prefix

  prefix="Mordhau"

  local server_directory
  local server_config
  server_directory="${BASE_DIR}/Server-${server_id}"
  server_config="${server_directory}/Mordhau/Saved/Config/LinuxServer/Game.ini"

  [[ -d "${server_directory}" ]] &&
    log "error" "A server already exists at ${server_directory}, delete it and try again" &&
    exit 1

  kill_server -s "${server_id}" >/dev/null 2>&1
  mkdir -p "${server_directory}" && log "info" "Created server directory ${server_directory}"

  steamcmd +login anonymous +force_install_dir "${server_directory}" +app_update 629800 validate +quit
  log "info" "Successfully installed Server-${server_id}"

  log "info" "Starting server to install default configuration files, please wait..."

  run_and_kill "${server_id}"

  cp "${server_config}" "Game-Primary.ini" &&
    log "info" "Created the Game-Primary.ini file"

  log "info" "Finished setting up Server-${server_id}"

}

usage() {
  # Print out usage instructions for the local script
  #
  # Arguments:
  #   None
  #
  # Usage:
  #   usage
  #
  # POSIX Compliant:
  #   Yes
  #
  printf "Usage: %s\n" \
    "$(basename ${0}) -h
  start
    Exposes options to start Mordhau Servers, pass -h to it for details
  kill
    Exposes options to kill Mordhau Servers, pass -h to it for details
  install
    Exposes options to install Mordhau Servers, pass -h to it for details
  update
    Exposes options to update Mordhau Servers, pass -h to it for details
  configure
    Exposes options to configure Mordhau Servers, pass -h to it for details"
}

parse_args() {
  # Parse input arguments
  #
  # Arguments:
  #   Consult the `usage` function
  #
  # Usage:
  #   parse_args "$@"
  #     - All arguments should be ingested by parse_args first for variable setting
  #
  # POSIX Compliant:
  #   Yes
  #

  while :; do
    case ${1} in
    -h | -\? | --help)
      usage # Display a usage synopsis.
      exit
      ;;
    --) # End of all options.
      break
      ;;
    start | s)
      shift
      start "$@"
      break
      ;;
    kill | k)
      shift
      kill_server "$@"
      break
      ;;
    install | i)
      shift
      install "$@"
      break
      ;;
    update | u)
      shift
      update "$@"
      break
      ;;
    configure | c)
      shift
      configure "$@"
      break
      ;;
    -?*)
      printf 'Unknown option: %s\n' "$1" >&2
      usage
      exit 1
      ;;
    *) # Default case: No more options, so break out of the loop.
      break ;;
    esac
    shift
  done
}

parse_args "$@"