# Build stage
FROM golang:1.23-alpine AS build

WORKDIR /app

# Cache deps
COPY go.mod go.sum ./
RUN go mod download

# Copy source and build
COPY . .
RUN go build -o ddns-updater main.go

# Runtime stage
FROM alpine:latest

WORKDIR /app

# Non-root user (optional)
RUN adduser -D ddns
USER ddns

# Copy binary
COPY --from=build /app/ddns-updater /usr/local/bin/ddns-updater

# Config volume
VOLUME ["/config"]

ENTRYPOINT ["/usr/local/bin/ddns-updater"]
CMD ["-config", "/config/config.yaml"]