# Build stage
FROM golang:1.21-alpine AS builder

# Install git and ca-certificates (needed for go mod download)
RUN apk add --no-cache git ca-certificates tzdata

# Create non-root user for security
RUN addgroup -g 1001 -S appgroup && \
    adduser -u 1001 -S appuser -G appgroup

# Set working directory
WORKDIR /app

# Copy go mod files
COPY go.mod go.sum ./

# Download dependencies
RUN go mod download

# Copy source code
COPY . .

# Build the application
RUN CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build \
    -ldflags='-w -s -extldflags "-static"' \
    -a -installsuffix cgo \
    -o bin/api \
    cmd/api/main.go

# Final stage
FROM scratch

# Copy ca-certificates from builder
COPY --from=builder /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/

# Copy timezone data
COPY --from=builder /usr/share/zoneinfo /usr/share/zoneinfo

# Copy user information from builder
COPY --from=builder /etc/passwd /etc/passwd
COPY --from=builder /etc/group /etc/group

# Copy the binary
COPY --from=builder /app/bin/api /api

# Copy configuration
COPY --from=builder /app/configs /configs

# Use non-root user
USER appuser:appgroup

# Expose port
EXPOSE 8080

# Health check
HEALTHCHECK --interval=30s --timeout=3s --start-period=5s --retries=3 \
    CMD ["/api", "-health-check"] || exit 1

# Set entrypoint
ENTRYPOINT ["/api"]