#!/bin/bash
# Build multi-architecture Docker image for web-gateway
# Supports: amd64 (x86_64) and arm64 (Raspberry Pi 4, Apple Silicon)

set -e

# Configuration
IMAGE_NAME="${IMAGE_NAME:-easylinux/web-gateway}"
IMAGE_TAG="${IMAGE_TAG:-latest}"
PLATFORMS="${PLATFORMS:-linux/amd64,linux/arm64}"

echo "============================================"
echo "Building Multi-Arch Docker Image"
echo "============================================"
echo "Image: ${IMAGE_NAME}:${IMAGE_TAG}"
echo "Platforms: ${PLATFORMS}"
echo "============================================"

# Check if buildx is available
if ! docker buildx version >/dev/null 2>&1; then
    echo "Error: docker buildx not found. Please install Docker Buildx."
    echo "See: https://docs.docker.com/buildx/working-with-buildx/"
    exit 1
fi

# Create builder instance if it doesn't exist
if ! docker buildx ls | grep -q multiarch-builder; then
    echo "Creating multiarch-builder..."
    docker buildx create --name multiarch-builder --use --bootstrap
else
    echo "Using existing multiarch-builder..."
    docker buildx use multiarch-builder
fi

# Build and push multi-arch image
echo "Building for platforms: ${PLATFORMS}..."

# Check if PUSH is set to true
if [ "${PUSH}" = "true" ]; then
    echo "Building and pushing to registry..."
    docker buildx build \
        --platform "${PLATFORMS}" \
        --tag "${IMAGE_NAME}:${IMAGE_TAG}" \
        --push \
        .
    
    echo "============================================"
    echo "✅ Multi-arch image built and pushed!"
    echo "============================================"
    echo "Image: ${IMAGE_NAME}:${IMAGE_TAG}"
    echo ""
    echo "Verify architectures:"
    echo "  docker buildx imagetools inspect ${IMAGE_NAME}:${IMAGE_TAG}"
else
    # For multi-arch, save to local registry cache
    echo "Building locally (use PUSH=true to push to registry)..."
    docker buildx build \
        --platform "${PLATFORMS}" \
        --tag "${IMAGE_NAME}:${IMAGE_TAG}" \
        .
    
    echo "============================================"
    echo "✅ Multi-arch image built successfully!"
    echo "============================================"
    echo "Image: ${IMAGE_NAME}:${IMAGE_TAG}"
    echo ""
    echo "Note: Multi-arch images are in buildx cache."
    echo "To push to registry:"
    echo "  PUSH=true ./build-multiarch.sh"
    echo ""
    echo "To load single arch locally:"
    echo "  docker buildx build --platform linux/amd64 -t ${IMAGE_NAME}:${IMAGE_TAG} --load ."
    echo "  or"
    echo "  docker buildx build --platform linux/arm64 -t ${IMAGE_NAME}:${IMAGE_TAG} --load ."
fi