#!/usr/bin/env bash
# Linux / macOS equivalent of run-all.ps1.
#
#   ./scripts/run-all.sh /path/to/jdk-25 [measureSeconds] [warmupSeconds]
#
# Everything published in the companion blog post came from the PowerShell version on Windows;
# this script produces the same set of files in results/ so the comparison can be repeated on
# server hardware, which is where you should actually make a decision.

set -euo pipefail

JAVA_HOME_ARG="${1:-${JAVA_HOME:-}}"
MEASURE_SECONDS="${2:-60}"
WARMUP_SECONDS="${3:-20}"

if [[ -z "$JAVA_HOME_ARG" ]]; then
  echo "usage: $0 /path/to/jdk-25 [measureSeconds] [warmupSeconds]" >&2
  exit 2
fi

ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
JAVA="$JAVA_HOME_ARG/bin/java"
JAVAC="$JAVA_HOME_ARG/bin/javac"
OUT="$ROOT/out"
RESULTS="$ROOT/results"
LOGS="$ROOT/logs"

mkdir -p "$OUT" "$RESULTS" "$LOGS"

# Fixed heap: -Xms == -Xmx removes heap resizing as a variable.
HEAP=(-Xms2g -Xmx2g)
STALL_HEAP=(-Xms512m -Xmx512m)

echo "==> compiling"
mapfile -t SOURCES < <(find "$ROOT/latency/src" "$ROOT/tuning/src" "$ROOT/internals/src" "$ROOT/analysis/src" -name '*.java')
"$JAVAC" -d "$OUT" "${SOURCES[@]}"

capture() {
  local name="$1"; shift
  echo "==> $name"
  "$@" > "$RESULTS/$name.txt" 2>&1 || true
  tail -n 4 "$RESULTS/$name.txt" | sed 's/^/    /'
}

capture 01-env-zgc  "$JAVA" -XX:+UseZGC  "${HEAP[@]}" "$ROOT/env/Env.java"
capture 01-env-g1   "$JAVA" -XX:+UseG1GC "${HEAP[@]}" "$ROOT/env/Env.java"

capture 02-flags-zgc "$JAVA" -XX:+UseZGC  "${HEAP[@]}" -XX:+PrintFlagsFinal -version
capture 02-flags-g1  "$JAVA" -XX:+UseG1GC "${HEAP[@]}" -XX:+PrintFlagsFinal -version

capture 03-latency-zgc "$JAVA" -XX:+UseZGC "${HEAP[@]}" \
  "-DwarmupSeconds=$WARMUP_SECONDS" "-Dseconds=$MEASURE_SECONDS" \
  "-Xlog:gc*,gc+heap=debug:file=$LOGS/zgc-latency.log:time,uptime,level,tags" \
  -cp "$OUT" com.ankurm.zgc.latency.LatencyHarness

capture 03-latency-g1 "$JAVA" -XX:+UseG1GC "${HEAP[@]}" \
  "-DwarmupSeconds=$WARMUP_SECONDS" "-Dseconds=$MEASURE_SECONDS" \
  "-Xlog:gc*,gc+heap=debug:file=$LOGS/g1-latency.log:time,uptime,level,tags" \
  -cp "$OUT" com.ankurm.zgc.latency.LatencyHarness

capture 04-stalls-zgc-baseline "$JAVA" -XX:+UseZGC "${STALL_HEAP[@]}" -Dseconds=20 \
  -cp "$OUT" com.ankurm.zgc.tuning.AllocationStallDemo
capture 04-stalls-zgc-softmax "$JAVA" -XX:+UseZGC -XX:SoftMaxHeapSize=400m "${STALL_HEAP[@]}" -Dseconds=20 \
  -cp "$OUT" com.ankurm.zgc.tuning.AllocationStallDemo
capture 04-stalls-zgc-spiketolerance "$JAVA" -XX:+UseZGC -XX:ZAllocationSpikeTolerance=5 "${STALL_HEAP[@]}" -Dseconds=20 \
  -cp "$OUT" com.ankurm.zgc.tuning.AllocationStallDemo
capture 04-stalls-g1 "$JAVA" -XX:+UseG1GC "${STALL_HEAP[@]}" -Dseconds=20 \
  "-Xlog:gc:file=$LOGS/g1-stress.log:time,uptime" \
  -cp "$OUT" com.ankurm.zgc.tuning.AllocationStallDemo

capture 05-pages-zgc "$JAVA" -XX:+UseZGC  "${HEAP[@]}" -cp "$OUT" com.ankurm.zgc.internals.PageSizeDemo
capture 05-pages-g1  "$JAVA" -XX:+UseG1GC "${HEAP[@]}" -cp "$OUT" com.ankurm.zgc.internals.PageSizeDemo

capture 06-gclog-zgc "$JAVA" -cp "$OUT" com.ankurm.zgc.analysis.GcLogParser "$LOGS/zgc-latency.log"
capture 06-gclog-g1  "$JAVA" -cp "$OUT" com.ankurm.zgc.analysis.GcLogParser "$LOGS/g1-latency.log"

echo "==> building JMH module"
(cd "$ROOT/jmh" && JAVA_HOME="$JAVA_HOME_ARG" mvn -q -B clean package)

# NOTE: the GC flag MUST be inside -jvmArgs. JMH forks a fresh JVM per trial and does not inherit
# flags from the outer `java -jar` command. See docs/06-methodology.md section 6.6.
for gc in UseZGC UseG1GC; do
  tag=$([[ "$gc" == "UseZGC" ]] && echo zgc || echo g1)
  capture "07-jmh-$tag" "$JAVA" -jar "$ROOT/jmh/target/benchmarks.jar" \
    -jvmArgs "-XX:+$gc -Xms2g -Xmx2g" -prof gc -rf json -rff "$RESULTS/07-jmh-$tag.json"
done

echo
echo "All raw output is in $RESULTS"