# CPU budget for the build. The self-hosted runner builds on the Raspberry Pi 5
# (4 cores) alongside live services, so we cap the CPU-heavy tools (the Go
# compiler and esbuild — both honour GOMAXPROCS) to leave cores for nginx/NPM
# and the other containers. Lower = gentler but slower; raise for a faster box.
ARG BUILD_CPUS=2

# ── Stage 1: Build frontend ───────────────────────────────────────────────────
FROM node:20-alpine AS frontend-builder
ARG BUILD_CPUS
# esbuild (used by Vite) is a Go program and respects GOMAXPROCS.
ENV GOMAXPROCS=${BUILD_CPUS}

WORKDIR /app/frontend
COPY frontend/package*.json ./
RUN npm install
COPY frontend/ ./
RUN npm run build

# ── Stage 2: Build backend ────────────────────────────────────────────────────
# Go 1.25 required by the OIDC dependency chain (go-oidc/v3, go-jose/v4).
FROM golang:1.25-alpine AS backend-builder
ARG BUILD_CPUS
# Cap the Go compiler's parallelism to keep the Pi responsive during CI.
ENV GOMAXPROCS=${BUILD_CPUS}

WORKDIR /app/backend
# Copy go.mod first for layer caching. go.sum is written by go mod download
# when it doesn't exist yet, or verified when it does.
COPY backend/go.mod ./
COPY backend/go.su[m] ./
RUN go mod download -x
COPY backend/ ./
# CGO disabled — pure Go SQLite (modernc.org/sqlite). -p limits parallel builds.
RUN CGO_ENABLED=0 go build -p ${BUILD_CPUS} -ldflags="-s -w" -o /archivum ./cmd/server

# ── Stage 3: Runtime image ────────────────────────────────────────────────────
FROM alpine:3.20

# su-exec: lightweight tool to drop privileges (replaces gosu / setpriv).
# git: needed for wiki commit operations.
# openssh-client: git-sync over ssh:// remotes (git shells out to ssh)
RUN apk add --no-cache su-exec git openssh-client

# Create the app group and user that the entrypoint will run as.
# PUID/PGID can be overridden at runtime via environment variables;
# the entrypoint script uses them rather than these build-time values.
RUN addgroup -g 1000 archivum \
 && adduser -u 1000 -G archivum -s /sbin/nologin -D archivum

COPY --from=frontend-builder /app/frontend/dist    /srv/archivum/ui
COPY --from=backend-builder  /archivum              /usr/local/bin/archivum
COPY docker/entrypoint.sh                           /usr/local/bin/entrypoint.sh
RUN chmod +x /usr/local/bin/entrypoint.sh

# Declare the volume mount points. The entrypoint creates subdirectories
# and fixes ownership before the application starts.
VOLUME ["/config", "/data"]

ENV DOCKER_PATH=/config \
    UI_DIR=/srv/archivum/ui \
    PUID=1000 \
    PGID=1000

# Entrypoint runs as root so it can chown the volumes, then drops to PUID:PGID.
EXPOSE 4000
ENTRYPOINT ["/usr/local/bin/entrypoint.sh"]