# Multi-stage build: build web bundle with Node, then build Go server, then produce a small runtime image

# 1) Build Web Components bundle (esbuild)
FROM node:20-alpine AS webbuild
WORKDIR /app

# Copy only what we need for the web build first (faster caching)
COPY package.json package-lock.json ./
COPY web ./web
# Ensure output directory exists (esbuild writes to server/static/js/tap.js)
RUN mkdir -p server/static/js

RUN npm ci && npm run build:wc

# 2) Build Go server
FROM golang:1.24-alpine AS gobuild
WORKDIR /app/server

# Copy Go module and source
COPY server/go.mod ./go.mod
COPY server/go.sum ./go.sum
# Pre-fetch modules for better caching
RUN go mod download

# Now copy the rest of the source (entire server tree)
COPY server/ ./

# Bring in built web assets from the previous stage (overwrites js bundle)
COPY --from=webbuild /app/server/static/js /app/server/static/js

ENV CGO_ENABLED=0 GOOS=linux GOARCH=amd64
RUN go build -o /app/server/app .

# 3) Runtime image
FROM alpine:3.19 AS runtime
RUN apk add --no-cache ca-certificates
WORKDIR /app/server

# Copy binary and runtime assets
COPY --from=gobuild /app/server/app ./app
COPY --from=gobuild /app/server/templates ./templates
COPY --from=gobuild /app/server/static ./static

# Fly will set PORT; our server defaults to 8088 if not set
ENV PORT=8088
EXPOSE 8088

# Security best-practice: run as non-root
RUN addgroup -S app && adduser -S app -G app
USER app

CMD ["./app"]