#!/bin/bash
# Profile-Guided Optimization (PGO) Implementation Script
# Expected Impact: 5-15% performance improvement
# See: AGENT_15_RUST_COMPILER_OPTIMIZATION_ANALYSIS.md

set -e

echo "=== Profile-Guided Optimization (PGO) Implementation ==="
echo ""

# Check if cargo-pgo is installed
if ! command -v cargo-pgo &> /dev/null; then
    echo "Installing cargo-pgo..."
    cargo install cargo-pgo
fi

# Step 1: Build instrumented binary
echo "Step 1: Building instrumented binary for profiling..."
RUSTFLAGS="-C target-cpu=native" cargo pgo build --release

# Step 2: Generate profile data with representative workloads
echo ""
echo "Step 2: Generating profile data with representative workloads..."

# Workload 1: Backtesting with real market data (ES.FUT 180 days)
echo "  - Running backtest with ES.FUT (180 days)..."
if [ -f "test_data/ES_FUT_180d.parquet" ]; then
    timeout 60s cargo run --release -p backtesting_service -- \
        --symbol ES.FUT --duration 180d --profile-output /tmp/pgo-profile || true
fi

# Workload 2: TFT training (ML hot path)
echo "  - Running TFT training (10 epochs for profiling)..."
if [ -f "test_data/ES_FUT_180d.parquet" ]; then
    timeout 120s cargo run --release -p ml --example train_tft_parquet --features cuda -- \
        --parquet-file test_data/ES_FUT_180d.parquet --epochs 10 \
        --profile-output /tmp/pgo-profile || true
fi

# Workload 3: Order matching benchmarks
echo "  - Running order matching benchmarks..."
timeout 60s cargo bench --bench performance_regression -- \
    --profile-output /tmp/pgo-profile || true

# Workload 4: API Gateway load test
echo "  - Running API Gateway proxy benchmarks..."
timeout 30s cargo bench --bench trading_latency -- \
    --profile-output /tmp/pgo-profile || true

# Step 3: Build optimized binary with profile data
echo ""
echo "Step 3: Building PGO-optimized binary..."
RUSTFLAGS="-C target-cpu=native" cargo pgo optimize --release

# Step 4: Run validation benchmarks
echo ""
echo "Step 4: Running validation benchmarks..."
echo "  - Baseline (before PGO)..."
git stash
cargo build --release
cargo bench --bench performance_regression -- --save-baseline pgo-before
git stash pop

echo "  - Optimized (after PGO)..."
cargo build --release --profile release-pgo
cargo bench --bench performance_regression -- --baseline pgo-before

# Step 5: Generate performance report
echo ""
echo "Step 5: Generating performance improvement report..."
cat << 'EOF' > /tmp/pgo_report.md
# PGO Performance Improvement Report

**Date**: $(date -u +%Y-%m-%d)
**Profile Data**: Representative HFT workload (backtest + ML training + benchmarks)

## Expected Improvements

| Benchmark | Before PGO | After PGO | Improvement |
|-----------|------------|-----------|-------------|
| Order Matching | TBD | TBD | TBD |
| Authentication | TBD | TBD | TBD |
| Order Submission | TBD | TBD | TBD |
| API Gateway Proxy | TBD | TBD | TBD |
| DBN Data Loading | TBD | TBD | TBD |
| TFT Inference | TBD | TBD | TBD |

**Target**: 5-15% improvement in CPU-bound hot paths

## Next Steps

1. Review benchmark results in `target/criterion/`
2. If improvements meet expectations (5-15%), deploy PGO builds to production
3. Update CI/CD pipeline to use PGO for release builds
4. Consider BOLT post-link optimization for additional 2-8% gains

See: AGENT_15_RUST_COMPILER_OPTIMIZATION_ANALYSIS.md for full analysis
EOF

echo ""
echo "✅ PGO implementation complete!"
echo ""
echo "Next steps:"
echo "1. Review benchmark results in target/criterion/"
echo "2. Check PGO report in /tmp/pgo_report.md"
echo "3. If successful, integrate into CI/CD pipeline"
echo "4. Proceed to Priority 2: Static linking (musl target)"