# ------------------------------------------------------------
# 1. Build stage
# ------------------------------------------------------------
FROM golang:1.25-alpine AS builder

RUN apk add --no-cache git

WORKDIR /app

# Dependencies first (cache friendly)
COPY go.mod go.sum ./
RUN go mod download

# Copy the entire codebase
COPY . .

# Build for the architecture of the host (ARM64 runner)
RUN CGO_ENABLED=0 go build -o server .

# ------------------------------------------------------------
# 2. Final minimal runtime image
# ------------------------------------------------------------
FROM alpine:3.20

RUN adduser -D -g '' appuser

WORKDIR /app

COPY --from=builder /app/server .

EXPOSE 8080

USER appuser

CMD ["./server"]