#!/bin/bash
# Performance Testing Script for debian-forge
# This script tests build performance and generates benchmarks

set -e

echo "🚀 Debian Forge Performance Testing"
echo "===================================="

# Configuration
TEST_DIR="./performance-tests"
RESULTS_DIR="./performance-results"
MANIFESTS_DIR="./test/data/manifests/debian"

# Create directories
mkdir -p "$TEST_DIR" "$RESULTS_DIR"

# Test configurations
declare -A TESTS=(
    ["debian-minimal"]="debian-trixie-minimal.json"
    ["ubuntu-server"]="ubuntu-jammy-server.json"
    ["debian-atomic"]="debian-atomic-container.json"
    ["debian-arm64"]="debian-trixie-arm64.json"
)

# Performance metrics
declare -A BUILD_TIMES
declare -A PACKAGE_COUNTS
declare -A IMAGE_SIZES

echo ""
echo "📊 Running Performance Tests..."
echo "==============================="

for test_name in "${!TESTS[@]}"; do
    manifest="${TESTS[$test_name]}"
    manifest_path="$MANIFESTS_DIR/$manifest"
    
    if [ ! -f "$manifest_path" ]; then
        echo "❌ Manifest not found: $manifest_path"
        continue
    fi
    
    echo ""
    echo "🧪 Testing: $test_name ($manifest)"
    echo "-----------------------------------"
    
    # Clean previous build
    rm -rf "$TEST_DIR/$test_name"
    mkdir -p "$TEST_DIR/$test_name"
    
    # Start timing
    start_time=$(date +%s.%N)
    
    # Run build
    echo "⏱️  Starting build..."
    if python3 -m osbuild "$manifest_path" --output-dir "$TEST_DIR/$test_name" --libdir . --json > "$RESULTS_DIR/${test_name}_build.json" 2>&1; then
        end_time=$(date +%s.%N)
        build_time=$(echo "$end_time - $start_time" | bc -l)
        BUILD_TIMES[$test_name]=$build_time
        
        echo "✅ Build completed in $(printf "%.2f" $build_time) seconds"
        
        # Extract package count from build log
        package_count=$(grep -o '"packages":\[[^]]*\]' "$RESULTS_DIR/${test_name}_build.json" | wc -l || echo "0")
        PACKAGE_COUNTS[$test_name]=$package_count
        
        # Calculate image size (if output exists)
        if [ -d "$TEST_DIR/$test_name" ]; then
            image_size=$(du -sh "$TEST_DIR/$test_name" 2>/dev/null | cut -f1 || echo "0B")
            IMAGE_SIZES[$test_name]=$image_size
        else
            IMAGE_SIZES[$test_name]="0B"
        fi
        
        echo "📦 Packages: $package_count"
        echo "💾 Size: ${IMAGE_SIZES[$test_name]}"
        
    else
        echo "❌ Build failed for $test_name"
        BUILD_TIMES[$test_name]="FAILED"
        PACKAGE_COUNTS[$test_name]="0"
        IMAGE_SIZES[$test_name]="0B"
    fi
done

echo ""
echo "📈 Performance Summary"
echo "======================"

# Create performance report
cat > "$RESULTS_DIR/performance-report.md" << EOF
# Debian Forge Performance Report

Generated: $(date)

## Build Times

| Test Case | Build Time | Status |
|-----------|------------|--------|
EOF

for test_name in "${!TESTS[@]}"; do
    build_time="${BUILD_TIMES[$test_name]}"
    if [ "$build_time" = "FAILED" ]; then
        status="❌ FAILED"
        time_display="N/A"
    else
        status="✅ SUCCESS"
        time_display="$(printf "%.2f" $build_time)s"
    fi
    
    echo "| $test_name | $time_display | $status |" >> "$RESULTS_DIR/performance-report.md"
done

cat >> "$RESULTS_DIR/performance-report.md" << EOF

## Package Counts

| Test Case | Package Count |
|-----------|---------------|
EOF

for test_name in "${!TESTS[@]}"; do
    package_count="${PACKAGE_COUNTS[$test_name]}"
    echo "| $test_name | $package_count |" >> "$RESULTS_DIR/performance-report.md"
done

cat >> "$RESULTS_DIR/performance-report.md" << EOF

## Image Sizes

| Test Case | Size |
|-----------|------|
EOF

for test_name in "${!TESTS[@]}"; do
    image_size="${IMAGE_SIZES[$test_name]}"
    echo "| $test_name | $image_size |" >> "$RESULTS_DIR/performance-report.md"
done

cat >> "$RESULTS_DIR/performance-report.md" << EOF

## Performance Analysis

### Fastest Build
EOF

# Find fastest build
fastest_time=999999
fastest_test=""
for test_name in "${!TESTS[@]}"; do
    build_time="${BUILD_TIMES[$test_name]}"
    if [ "$build_time" != "FAILED" ]; then
        if (( $(echo "$build_time < $fastest_time" | bc -l) )); then
            fastest_time=$build_time
            fastest_test=$test_name
        fi
    fi
done

if [ -n "$fastest_test" ]; then
    echo "- **$fastest_test**: $(printf "%.2f" $fastest_time)s" >> "$RESULTS_DIR/performance-report.md"
else
    echo "- No successful builds" >> "$RESULTS_DIR/performance-report.md"
fi

cat >> "$RESULTS_DIR/performance-report.md" << EOF

### Slowest Build
EOF

# Find slowest build
slowest_time=0
slowest_test=""
for test_name in "${!TESTS[@]}"; do
    build_time="${BUILD_TIMES[$test_name]}"
    if [ "$build_time" != "FAILED" ]; then
        if (( $(echo "$build_time > $slowest_time" | bc -l) )); then
            slowest_time=$build_time
            slowest_test=$test_name
        fi
    fi
done

if [ -n "$slowest_test" ]; then
    echo "- **$slowest_test**: $(printf "%.2f" $slowest_time)s" >> "$RESULTS_DIR/performance-report.md"
else
    echo "- No successful builds" >> "$RESULTS_DIR/performance-report.md"
fi

cat >> "$RESULTS_DIR/performance-report.md" << EOF

## Recommendations

1. **Use apt-cacher-ng** for 2-3x faster builds
2. **Minimize package count** for faster builds
3. **Use minimal base images** when possible
4. **Monitor build times** regularly
5. **Optimize manifest structure** for better performance

## Next Steps

1. Implement apt-cacher-ng integration
2. Add parallel build support
3. Optimize package installation
4. Add build caching
5. Monitor memory usage

EOF

echo ""
echo "📊 Performance Report Generated"
echo "==============================="
echo "📄 Report: $RESULTS_DIR/performance-report.md"
echo "📁 Results: $RESULTS_DIR/"
echo "🧪 Test Data: $TEST_DIR/"

echo ""
echo "🎯 Performance Summary:"
echo "======================="

for test_name in "${!TESTS[@]}"; do
    build_time="${BUILD_TIMES[$test_name]}"
    package_count="${PACKAGE_COUNTS[$test_name]}"
    image_size="${IMAGE_SIZES[$test_name]}"
    
    if [ "$build_time" = "FAILED" ]; then
        echo "❌ $test_name: FAILED"
    else
        echo "✅ $test_name: $(printf "%.2f" $build_time)s | $package_count packages | $image_size"
    fi
done

echo ""
echo "🚀 Performance testing completed!"