# Builder stage
FROM golang:1.26-alpine AS builder

# Install C compiler and musl headers required for CGO + go-sqlite3
RUN apk add --no-cache gcc musl-dev

# Enable CGO (required by github.com/mattn/go-sqlite3)
ENV CGO_ENABLED=1

# Cache build and module caches for faster rebuilds
ENV GOCACHE=/go-cache
ENV GOMODCACHE=/go/pkg/mod

# Set working directory
WORKDIR /build

# Copy dependency manifests first and download modules (cache layer)
COPY go.mod go.sum ./
RUN go mod download

# Copy the rest of the source code
COPY . .

# Build a static-ish binary (C code for SQLite is compiled in; musl libc stays dynamic)
RUN go build -o /app/server ./cmd/server/

# Runtime stage
FROM alpine:3.20

# ca-certificates for TLS, tzdata for timezone support
RUN apk add --no-cache ca-certificates tzdata

# Create non-root user for better security
RUN addgroup -S app && adduser -S app -G app

# Set working directory
WORKDIR /app

# Copy the binary from the builder stage
COPY --from=builder /app/server /app/server
RUN chmod +x /app/server

# Copy static and template assets from the project source
COPY --from=builder /build/static /app/static
COPY --from=builder /build/templates /app/templates

# Ensure the app user owns the working dir
RUN chown -R app:app /app

# Create data directory owned by app user (for named volume mount)
RUN mkdir -p /data && chown app:app /data

USER app

# Expose the HTTP port
EXPOSE 8080

# Default command (runs as 'app' user, DB stored in named volume)
CMD ["/app/server", "-addr", ":8080", "-db", "/data/state.db"]