FROM "${JRE_IMAGE:-localhost/minecraft-jre}":"${JRE_TAG:-latest}"

# Minecraft version to download
ARG VERSION=latest

# Download files and run as user
USER minecraft
WORKDIR /app

# Download and verify sha1sum for server.jar
RUN set -eux && \
# Grab latest version if not specified
  if [ "$VERSION" = "latest" ]; then \
    VERSION="$( \
      curl -s https://launchermeta.mojang.com/mc/game/version_manifest.json \
        | jq -r '.latest.release' \
    )"; \
  fi && \
  # Get server.jar based on $VERSION
  curl -s https://launchermeta.mojang.com/mc/game/version_manifest.json \
    | jq -r --arg id "$VERSION" '.versions[] | select(.id == $id) | .url' \
    | xargs curl -s | jq -r '.downloads.server' | tee "/tmp/dl.json" \
    | jq -r '.url' | xargs curl -s -o server.jar && \
  # Get SHA1 hash of server.jar and compare
  SHA1="$(sha1sum server.jar | awk '{print $1}')" && \
  EXPECTED="$(jq -r .sha1 /tmp/dl.json)"; rm /tmp/dl.json && \
  if [ ! "$SHA1" = "$EXPECTED" ]; then \
    echo "[ERROR]: SHA1=\"$SHA1\" expected \"$EXPECTED\""; \
    exit 1; \
  fi

# Generate initial settings
RUN java -jar server.jar --initSettings --nogui

# Back to root to copy the entrypoint in
USER root
WORKDIR /app

# Copy in entrypoint script
COPY ../entrypoint.sh /usr/local/bin/entrypoint.sh
RUN chmod +x /usr/local/bin/entrypoint.sh

# Run app as minecraft user
USER minecraft
WORKDIR /app

# Expose port and run entrypoint script
EXPOSE 25565
ENTRYPOINT ["entrypoint.sh"]