#!/bin/bash
#
# Smartbotic Production Build Script
#
# This script handles the Docker build workflow:
# 1. Checks if the pre-built base image exists
# 2. Creates it if needed
# 3. Builds production packages using the base image
#
# Usage:
#   ./packaging/build.sh              # Build with auto-detected version
#   ./packaging/build.sh 0.1.0        # Build with specific version
#   ./packaging/build.sh --rebuild-base  # Force rebuild the base image
#

set -e

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
PROJECT_DIR="$(cd "${SCRIPT_DIR}/.." && pwd)"
cd "$PROJECT_DIR"

# Configuration
BASE_IMAGE_NAME="smartbotic-build-base:debian13"
OUTPUT_DIR="${PROJECT_DIR}/dist"
BUILD_JOBS="${BUILD_JOBS:-16}"

# Colors for output
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
BLUE='\033[0;34m'
NC='\033[0m' # No Color

log_info() {
    echo -e "${BLUE}[INFO]${NC} $1"
}

log_success() {
    echo -e "${GREEN}[OK]${NC} $1"
}

log_warn() {
    echo -e "${YELLOW}[WARN]${NC} $1"
}

log_error() {
    echo -e "${RED}[ERROR]${NC} $1"
}

# Parse arguments
REBUILD_BASE=false
CLEAR_CACHE=false
NO_CACHE=false
VERSION=""

while [[ $# -gt 0 ]]; do
    case $1 in
        --rebuild-base)
            REBUILD_BASE=true
            shift
            ;;
        --clear-cache)
            CLEAR_CACHE=true
            shift
            ;;
        --no-cache)
            NO_CACHE=true
            shift
            ;;
        --help|-h)
            echo "Smartbotic Production Build Script"
            echo ""
            echo "Usage: $0 [OPTIONS] [VERSION]"
            echo ""
            echo "Options:"
            echo "  --rebuild-base    Force rebuild the base image"
            echo "  --clear-cache     Clear BuildKit build caches (ccache, npm)"
            echo "  --no-cache        Build without using caches"
            echo "  --help, -h        Show this help message"
            echo ""
            echo "Arguments:"
            echo "  VERSION           Version string (default: auto-detect from CMakeLists.txt)"
            echo ""
            echo "Environment variables:"
            echo "  BUILD_JOBS        Number of parallel build jobs (default: 16)"
            echo ""
            echo "Examples:"
            echo "  $0                # Build with auto-detected version"
            echo "  $0 0.1.0          # Build version 0.1.0"
            echo "  $0 --rebuild-base # Rebuild base image and build packages"
            echo "  $0 --clear-cache  # Clear caches and build fresh"
            exit 0
            ;;
        *)
            VERSION="$1"
            shift
            ;;
    esac
done

# Auto-detect version if not specified
if [ -z "$VERSION" ]; then
    VERSION=$(grep -oP 'project\(smartbotic-microbit VERSION \K[0-9.]+' CMakeLists.txt)
    if [ -z "$VERSION" ]; then
        log_error "Could not detect version from CMakeLists.txt"
        exit 1
    fi
fi

log_info "Smartbotic Build Script"
log_info "Version: $VERSION"
log_info "Output directory: $OUTPUT_DIR"
echo ""

# Check if Docker is available
if ! command -v docker &> /dev/null; then
    log_error "Docker is not installed or not in PATH"
    exit 1
fi

# Check if base image exists
base_image_exists() {
    docker image inspect "$BASE_IMAGE_NAME" &> /dev/null
}

# Build base image
build_base_image() {
    log_info "Building base image: $BASE_IMAGE_NAME"
    log_info "This may take several minutes on first run..."
    echo ""

    docker buildx build \
        -f packaging/Dockerfile.base \
        -t "$BASE_IMAGE_NAME" \
        .

    log_success "Base image built successfully"
    echo ""
}

# Build production packages
build_packages() {
    log_info "Building production packages..."
    log_info "Using base image: $BASE_IMAGE_NAME"
    log_info "Build jobs: $BUILD_JOBS"
    if [ "$NO_CACHE" = true ]; then
        log_warn "Building without caches (--no-cache)"
    else
        log_info "Using ccache and npm cache for faster builds"
    fi
    echo ""

    # Get git info
    GIT_COMMIT=$(git rev-parse HEAD 2>/dev/null || echo "unknown")
    GIT_BRANCH=$(git rev-parse --abbrev-ref HEAD 2>/dev/null || echo "unknown")

    log_info "Git commit: $GIT_COMMIT"
    log_info "Git branch: $GIT_BRANCH"
    echo ""

    # Clean output directory
    rm -rf "$OUTPUT_DIR"
    mkdir -p "$OUTPUT_DIR"

    # Build arguments
    BUILD_ARGS=(
        -f packaging/Dockerfile.build
        --build-arg BASE_IMAGE="$BASE_IMAGE_NAME"
        --build-arg BUILD_VERSION="$VERSION"
        --build-arg BUILD_GIT_COMMIT="$GIT_COMMIT"
        --build-arg BUILD_GIT_BRANCH="$GIT_BRANCH"
        --build-arg BUILD_JOBS="$BUILD_JOBS"
        --target packages
        --output "type=local,dest=$OUTPUT_DIR"
    )

    # Add --no-cache if requested
    if [ "$NO_CACHE" = true ]; then
        BUILD_ARGS+=(--no-cache)
    fi

    # Build packages
    docker buildx build "${BUILD_ARGS[@]}" .

    log_success "Packages built successfully"
    echo ""
}

# Clear build caches
clear_build_cache() {
    log_info "Clearing BuildKit build caches..."
    docker builder prune --filter type=exec.cachemount -f
    log_success "Build caches cleared"
    echo ""
}

# Main flow
echo "=================================================="
echo "  Smartbotic Production Build"
echo "  Version: $VERSION"
echo "=================================================="
echo ""

# Clear cache if requested
if [ "$CLEAR_CACHE" = true ]; then
    clear_build_cache
fi

# Check/build base image
if [ "$REBUILD_BASE" = true ]; then
    log_warn "Force rebuilding base image..."
    build_base_image
elif base_image_exists; then
    log_success "Base image found: $BASE_IMAGE_NAME"
else
    log_warn "Base image not found, building..."
    build_base_image
fi

# Build packages
build_packages

# List created packages
echo "=================================================="
echo "  Build Complete"
echo "=================================================="
echo ""
log_info "Created packages in $OUTPUT_DIR:"
echo ""
ls -lh "$OUTPUT_DIR"/*.tar.gz 2>/dev/null | while read line; do
    echo "  $line"
done
echo ""

# Calculate total size
TOTAL_SIZE=$(du -sh "$OUTPUT_DIR" | cut -f1)
log_info "Total size: $TOTAL_SIZE"
echo ""

# Show cache info
echo "=================================================="
echo "  Build Cache Info"
echo "=================================================="
echo ""
log_info "BuildKit caches (ccache, npm) are stored persistently."
log_info "Subsequent builds will be faster due to compilation caching."
echo ""
log_info "Cache management commands:"
echo "  $0 --clear-cache   # Clear all build caches"
echo "  $0 --no-cache      # Build without using caches"
echo ""

log_success "Build completed successfully!"
echo ""
echo "To deploy to production:"
echo "  scp dist/*.tar.gz root@<server>:/tmp/smartbotic-update/"
echo "  ssh root@<server> '/opt/smartbotic/bin/smartbotic-update --rolling --backup /tmp/smartbotic-update/'"
echo ""