# Find eligible builder and runner images on Docker Hub. We use Ubuntu/Debian
# instead of Alpine to avoid DNS resolution issues in production.
#
# https://hub.docker.com/r/hexpm/elixir/tags?page=1&name=ubuntu
# https://hub.docker.com/_/ubuntu?tab=tags
#
# This file is based on these images:
#
#   - https://hub.docker.com/r/hexpm/elixir/tags - for the build image
#   - https://hub.docker.com/_/debian?tab=tags&page=1&name=bullseye-20240904-slim - for the release image
#   - https://pkgs.org/ - resource for finding needed packages
#   - Ex: hexpm/elixir:1.17.2-erlang-27.1-debian-bullseye-20240904-slim
#
ARG ELIXIR_VERSION=1.20.0-rc.6
ARG OTP_VERSION=29.0.1
ARG DEBIAN_VERSION=trixie-20260518-slim

ARG BUILDER_IMAGE="hexpm/elixir:${ELIXIR_VERSION}-erlang-${OTP_VERSION}-debian-${DEBIAN_VERSION}"
ARG RUNNER_IMAGE="debian:${DEBIAN_VERSION}"

FROM node:26-slim AS node

FROM ${BUILDER_IMAGE} AS builder

# install build dependencies
RUN apt-get update -y && apt-get install -y --no-install-recommends build-essential git \
  && apt-get clean && rm -f /var/lib/apt/lists/*_*

# copy Node.js from the official image
COPY --from=node /usr/local/bin/node /usr/local/bin/node
COPY --from=node /usr/local/lib/node_modules /usr/local/lib/node_modules
RUN ln -s /usr/local/lib/node_modules/npm/bin/npm-cli.js /usr/local/bin/npm

SHELL ["/bin/bash", "-euo", "pipefail", "-c"]

# prepare build dir
WORKDIR /app

# install hex + rebar
RUN mix local.hex --force && \
  mix local.rebar --force

# install Fluxon UI repo
RUN --mount=type=secret,id=FLUXON_LICENSE_KEY \
  --mount=type=secret,id=FLUXON_KEY_FINGERPRINT \
  mix hex.repo add fluxon https://repo.fluxonui.com \
  --fetch-public-key "$(cat /run/secrets/FLUXON_KEY_FINGERPRINT)" \
  --auth-key "$(cat /run/secrets/FLUXON_LICENSE_KEY)"

# set build ENV
ENV MIX_ENV="prod"
ENV ERL_FLAGS="+JPperf true"

# install mix dependencies
COPY mix.exs mix.lock ./
RUN mix deps.get --only $MIX_ENV
RUN mkdir config

# copy compile-time config files before we compile dependencies
# to ensure any relevant config change will trigger the dependencies
# to be re-compiled.
COPY config/config.exs config/${MIX_ENV}.exs config/
RUN mix deps.compile

COPY priv priv

COPY lib lib

# install npm deps first (cached unless lock changes)
COPY assets/package.json assets/package-lock.json ./assets/
RUN npm ci --prefix assets

COPY assets assets

# compile the release, then build assets
RUN mix compile
RUN mix assets.deploy

# Changes to config/runtime.exs don't require recompiling the code
COPY config/runtime.exs config/

COPY rel rel
RUN mix release

# start a new build stage so that the final image will only contain
# the compiled release and other runtime necessities
FROM ${RUNNER_IMAGE}

RUN apt-get update -y && \
  apt-get install -y --no-install-recommends libstdc++6 openssl libncurses6 locales ca-certificates \
  && apt-get clean && rm -f /var/lib/apt/lists/*_*

# Set the locale and strip unused locale data
RUN sed -i '/en_US.UTF-8/s/^# //g' /etc/locale.gen && locale-gen \
  && rm -rf /usr/share/locale /usr/share/i18n

SHELL ["/bin/bash", "-euo", "pipefail", "-c"]

ENV LANG=en_US.UTF-8
ENV LANGUAGE=en_US:en
ENV LC_ALL=en_US.UTF-8

WORKDIR "/app"
RUN chown nobody /app

# set runner ENV
ENV MIX_ENV="prod"

# Only copy the final release from the build stage
COPY --from=builder --chown=nobody:root /app/_build/${MIX_ENV}/rel/music_library ./

USER nobody

# If using an environment that doesn't automatically reap zombie processes, it is
# advised to add an init process such as tini via `apt-get install`
# above and adding an entrypoint. See https://github.com/krallin/tini for details
# ENTRYPOINT ["/tini", "--"]

CMD ["/app/bin/server"]
