# Stage 1: build
# Use the native build platform so npm ci never runs under QEMU emulation.
# The build output (static HTML/JS/CSS) is platform-independent.
# node:20-slim (Debian/glibc) avoids lightningcss musl binary resolution issues on Alpine.
FROM --platform=$BUILDPLATFORM node:20-slim AS builder

ARG VITE_STANDALONE=false
ENV VITE_STANDALONE=$VITE_STANDALONE

# Subpath support: build with VITE_BASE_PATH=/homelab/ to serve Homelable under a
# prefix instead of the root of an origin. The default '/' produces the same build
# as before the option existed.
ARG VITE_BASE_PATH=/
ENV VITE_BASE_PATH=$VITE_BASE_PATH

WORKDIR /app
COPY frontend/package*.json ./
RUN npm ci

COPY frontend/ .
COPY VERSION ../VERSION
RUN npm run build

# Stage 2: serve
FROM nginx:alpine

COPY --from=builder /app/dist /tmp/dist

# Nginx config: standalone (no backend proxy) or full, served at the root or under the
# VITE_BASE_PATH prefix. At the root the build lands in /usr/share/nginx/html and the
# shipped .conf is copied verbatim, so an existing deployment gets exactly what it had
# before this option existed. Under a prefix the build lands in the matching
# subdirectory, which keeps the generated config on plain `root` semantics.
ARG VITE_STANDALONE=false
ARG VITE_BASE_PATH=/
COPY docker/nginx.conf docker/nginx.standalone.conf /tmp/nginx-conf/
COPY docker/nginx.subpath.conf.template docker/nginx.standalone.subpath.conf.template /tmp/nginx-conf/
# ash with pipefail: the base-path normalization below pipes printf into sed.
SHELL ["/bin/ash", "-eo", "pipefail", "-c"]
RUN set -eu; \
    if [ "$VITE_STANDALONE" = "true" ]; then variant=nginx.standalone; else variant=nginx; fi; \
    base=$(printf '%s' "${VITE_BASE_PATH:-/}" | sed -e 's#^/*#/#' -e 's#/*$#/#' -e 's#//*#/#g'); \
    [ -n "$base" ] || base=/; \
    mkdir -p "/usr/share/nginx/html${base}"; \
    cp -a /tmp/dist/. "/usr/share/nginx/html${base}"; \
    if [ "$base" = "/" ]; then \
      cp "/tmp/nginx-conf/${variant}.conf" /etc/nginx/conf.d/default.conf; \
    else \
      sed -e "s#__BASE_NO_SLASH__#${base%/}#g" -e "s#__BASE__#${base}#g" \
        "/tmp/nginx-conf/${variant}.subpath.conf.template" > /etc/nginx/conf.d/default.conf; \
    fi; \
    rm -rf /tmp/dist /tmp/nginx-conf

EXPOSE 80