# syntax=docker/dockerfile:1.7
#
# Multi-stage build for the helix-engage sidecar.
#
# Why multi-stage instead of "build on host, COPY dist + node_modules"?
# The host (developer Mac, CI runner) is rarely the same architecture
# as the target (linux/amd64 EC2 / VPS). Copying a host-built
# node_modules brings darwin-arm64 native bindings (sharp, livekit,
# fsevents, etc.) into the runtime image, which crash on first import.
# This Dockerfile rebuilds inside the target-platform container so
# native bindings are downloaded/compiled for the right arch.
#
# The build stage runs `npm ci` + `nest build`, then `npm prune` to
# strip dev deps. The runtime stage carries forward only `dist/`,
# the pruned `node_modules/`, and `package.json`.

# --- Builder stage ----------------------------------------------------------
FROM node:22-slim AS builder
WORKDIR /app

# Build deps for any native modules whose prebuilt binaries miss the
# target arch. Kept minimal — node:22-slim already ships most of what's
# needed for the deps in this project, but python/make/g++ are the
# canonical "I might need to gyp-rebuild" trio.
RUN apt-get update \
 && apt-get install -y --no-install-recommends \
        python3 \
        make \
        g++ \
 && rm -rf /var/lib/apt/lists/*

# Lockfile-only install first so this layer caches when only source
# changes — much faster repeat builds.
COPY package.json package-lock.json ./
RUN npm ci --no-audit --no-fund --loglevel=verbose

# Source + build config
COPY tsconfig.json tsconfig.build.json nest-cli.json ./
COPY src ./src

RUN npm run build

# Strip dev dependencies so the runtime image stays small.
RUN npm prune --omit=dev


# --- Runtime stage ----------------------------------------------------------
FROM node:22-slim
WORKDIR /app

# Bring across only what the runtime needs. Source, dev deps, build
# tooling all stay in the builder stage and get discarded.
COPY --from=builder /app/dist ./dist
COPY --from=builder /app/node_modules ./node_modules
COPY --from=builder /app/package.json ./

EXPOSE 4100
CMD ["node", "dist/main.js"]