# === Build stage ===
# Updated to JDK 25 for better performance and longer support
FROM eclipse-temurin:25-jdk AS build

# Modern GPG handling & sbt install
RUN apt-get update && apt-get install -y curl gnupg && \
    curl -sL "https://keyserver.ubuntu.com/pks/lookup?op=get&search=0x2EE0EA64E40A89B84B2DF73499E82A75642AC823" | gpg --dearmor > /etc/apt/trusted.gpg.d/sbt.gpg && \
    echo "deb https://repo.scala-sbt.org/scalasbt/debian all main" > /etc/apt/sources.list.d/sbt.list && \
    apt-get update && apt-get install -y sbt && \
    rm -rf /var/lib/apt/lists/*

WORKDIR /app

# Optimization: Copy ALL build definitions first
# This ensures caching works if your source code changes but dependencies don't.
COPY build.sbt .
COPY project/*.sbt project/*.properties project/*.scala project/
RUN sbt update

# Build the assembly (Fat JAR)
COPY src/ src/
RUN sbt "set test in assembly := false" assembly

# === Runtime stage ===
# Updated to the latest JRE 25 on Alpine
FROM eclipse-temurin:25-jre-alpine

# Security: Create a non-root user
RUN addgroup -S app && adduser -S app -G app
WORKDIR /app

# Adjust path for Scala 3.7.1
COPY --from=build --chown=app:app /app/target/scala-3.7.1/demoapp.jar ./demoapp.jar

USER app
EXPOSE 8080

# Optimization: Use cgroup-aware RAM limits
ENV PORT=8080
ENV JAVA_OPTS="-XX:MaxRAMPercentage=75.0 -XX:+UseContainerSupport -XX:+ExitOnOutOfMemoryError"

ENTRYPOINT ["sh", "-c", "exec java $JAVA_OPTS -jar demoapp.jar"]