#!/bin/bash

: "${FORGEVERSION:=RECOMMENDED}"

# shellcheck source=start-utils
. "${SCRIPTS:-$(dirname "$0")}/start-utils"
isDebugging && set -x

get_installer() {
  if [[ -z $FORGE_INSTALLER_URL ]]; then
    log "Downloading $normForgeVersion"

    forgeFileNames="
    $normForgeVersion/forge-$normForgeVersion-installer.jar
    $shortForgeVersion/forge-$shortForgeVersion-installer.jar
  "

    for fn in $forgeFileNames; do
      downloadUrl=https://maven.minecraftforge.net/net/minecraftforge/forge/$fn
      log "...trying $downloadUrl"
      if get -o "$FORGE_INSTALLER" "$downloadUrl"; then
        return
      fi
    done
    log "Unable to locate usable URL for $normForgeVersion"
    exit 2
 else
    log "Downloading $FORGE_INSTALLER_URL ..."
    if ! get -o "$FORGE_INSTALLER" "$FORGE_INSTALLER_URL"; then
      log "Failed to download from given location $FORGE_INSTALLER_URL"
      exit 2
    fi
  fi
}

install() {
  if [ ! -e "$FORGE_INSTALLER" ]; then
    get_installer "$normForgeVersion" "$shortForgeVersion"
  fi

  log "Installing Forge $shortForgeVersion using $FORGE_INSTALLER"
  mkdir -p mods
  tries=3
  while ((--tries >= 0)); do
    if java -jar "$FORGE_INSTALLER" --installServer; then
      break
    fi
  done
  if ((tries < 0)); then
    log "Forge failed to install after several tries." >&2
    exit 10
  fi
  # NOTE $shortForgeVersion will be empty if installer location was given to us
  log "Finding installed server jar..."
  unset -v latest
  # 1.17+ ?
  if [ -f /data/run.sh ]; then
    latest=/data/run.sh
  # else pre 1.17
  else
    for file in *forge*.jar; do
      if ! [[ $file =~ installer ]]; then
        if [[ -z $latest ]] || [[ $file -nt $latest ]]; then
          latest=$file
        fi
      fi
    done
  fi
  if [[ -z $latest ]]; then
    log "Unable to derive server jar for Forge"
    exit 2
  fi

  export SERVER=$latest
  log "Using server $SERVER"
  debug "Writing install marker at $installMarker"
  echo "$SERVER" > "$installMarker"
}

resolve_versions() {
  if [[ -z $FORGE_INSTALLER && -z $FORGE_INSTALLER_URL ]]; then
    norm=$VANILLA_VERSION

    case $VANILLA_VERSION in
      *.*.*)
        norm=$VANILLA_VERSION ;;
      *.*)
        norm=${VANILLA_VERSION}.0 ;;
    esac

    #################################################################################
    promosUrl=http://files.minecraftforge.net/maven/net/minecraftforge/forge/promotions_slim.json

    log "Checking Forge version information."
    case $FORGEVERSION in
      LATEST)
        if ! FORGE_VERSION=$(get --json-path ".promos['$VANILLA_VERSION-latest']" "$promosUrl"); then
          log "ERROR: Version $VANILLA_VERSION is not supported by Forge"
          log "       Refer to http://files.minecraftforge.net/ for supported versions"
          exit 2
        fi
        ;;

      RECOMMENDED)
        if ! FORGE_VERSION=$(get --json-path ".promos['$VANILLA_VERSION-recommended']" "$promosUrl"); then
          if ! FORGE_VERSION=$(get --json-path ".promos['$VANILLA_VERSION-latest']" "$promosUrl"); then
            log "ERROR: Version $VANILLA_VERSION is not supported by Forge"
            log "       Refer to http://files.minecraftforge.net/ for supported versions"
            exit 2
          fi
        fi
        ;;

      *)
        FORGE_VERSION=$FORGEVERSION
        ;;
    esac

    normForgeVersion=$VANILLA_VERSION-$FORGE_VERSION-$norm
    shortForgeVersion=$VANILLA_VERSION-$FORGE_VERSION

    FORGE_INSTALLER="/tmp/forge-$shortForgeVersion-installer.jar"
  elif [[ -z $FORGE_INSTALLER ]]; then
    FORGE_INSTALLER="/tmp/forge-installer.jar"
  elif [[ ! -e $FORGE_INSTALLER ]]; then
    log "ERROR: the given Forge installer doesn't exist : $FORGE_INSTALLER"
    exit 2
  else
    shortForgeVersion=$VANILLA_VERSION-${FORGE_INSTALLER_CUSTOM_VERSION:-custom}
  fi
}

### main

resolve_versions

installMarker="/data/.forge-installed-$shortForgeVersion"

if [ ! -e "$installMarker" ] || isTrue "${FORCE_REINSTALL:-false}"; then
  install
else
  SERVER=$(cat "$installMarker")
  export SERVER
  if [ ! -e "$SERVER" ]; then
    rm "$installMarker"
    install
  fi
fi

exec "${SCRIPTS:-/}start-setupWorld" "$@"