#!/usr/bin/env bash
set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
ROOT="$(cd "$SCRIPT_DIR/../.." && pwd)"
BIN="$ROOT/target/release/hakorune"

usage() { echo "Usage: $0 --case {loop|strlen|box} [--n N] [--runs R] [--backend {llvm|vm}] [--exe]"; }

CASE="loop"; N=5000000; RUNS=5; BACKEND="llvm"; EXE_MODE=0
while [[ $# -gt 0 ]]; do
  case "$1" in
    --case) CASE="$2"; shift 2;;
    --n) N="$2"; shift 2;;
    --runs) RUNS="$2"; shift 2;;
    --backend) BACKEND="$2"; shift 2;;
    --exe) EXE_MODE=1; shift 1;;
    --help|-h) usage; exit 0;;
    *) echo "Unknown arg: $1"; usage; exit 2;;
  esac
done

if [[ ! -x "$BIN" ]]; then echo "[FAIL] hakorune not built: $BIN" >&2; exit 2; fi

bench_hako() {
  local file="$1"; local backend="$2"; shift 2
  local start end
  start=$(date +%s%N)
  if [[ "$backend" = "llvm" ]]; then
    # Ensure ny-llvmc exists; build if missing
    if [[ ! -x "$ROOT/target/release/ny-llvmc" ]]; then
      (cargo build -q --release -p nyash-llvm-compiler >/dev/null 2>&1) || true
    fi
    PYTHONPATH="${PYTHONPATH:-$ROOT}" \
    NYASH_NY_LLVM_COMPILER="${NYASH_NY_LLVM_COMPILER:-$ROOT/target/release/ny-llvmc}" \
    NYASH_EMIT_EXE_NYRT="${NYASH_EMIT_EXE_NYRT:-$ROOT/target/release}" \
    NYASH_LLVM_USE_HARNESS=1 "$BIN" --backend llvm "$file" >/dev/null 2>&1
  else
    "$BIN" --backend vm "$file" >/dev/null 2>&1
  fi
  end=$(date +%s%N)
  echo $(( (end - start)/1000000 ))
}

bench_c() {
  local csrc="$1"; local exe="$2"
  cc -O3 -march=native -o "$exe" "$csrc"
  local start end
  start=$(date +%s%N)
  "$exe" >/dev/null 2>&1
  end=$(date +%s%N)
  echo $(( (end - start)/1000000 ))
}

# Build once and time executable runs (ms)
time_exe_run() {
  local exe="$1"
  local start end
  start=$(date +%s%N)
  "$exe" >/dev/null 2>&1
  end=$(date +%s%N)
  echo $(( (end - start)/1000000 ))
}

mktemp_hako() { mktemp --suffix .hako; }
mktemp_c() { mktemp --suffix .c; }

case "$CASE" in
  loop)
    HAKO_FILE=$(mktemp_hako)
    cat >"$HAKO_FILE" <<HAKO
static box Main { method main(args) {
  local n = ${N}
  local i = 0
  local s = 0
  loop(i < n) { s = s + i  i = i + 1 }
  return s
} }
HAKO
    C_FILE=$(mktemp_c)
    cat >"$C_FILE" <<'C'
#include <stdint.h>
int main(){
  volatile int64_t n = N_PLACEHOLDER;
  volatile int64_t s=0; for (int64_t i=0;i<n;i++){ s+=i; }
  return (int)(s&0xFF);
}
C
    sed -i "s/N_PLACEHOLDER/${N}/" "$C_FILE"
    ;;
  strlen)
    HAKO_FILE=$(mktemp_hako)
    cat >"$HAKO_FILE" <<HAKO
static box Main { method main(args) {
  local n = ${N}
  local i = 0
  local s = 0
  local t = "abcdefghijklmnopqrstuvwxyz"
  loop(i < n) { s = s + t.length()  i = i + 1 }
  return s
} }
HAKO
    C_FILE=$(mktemp_c)
    cat >"$C_FILE" <<'C'
#include <stdint.h>
#include <string.h>
int main(){
  volatile int64_t n = N_PLACEHOLDER; volatile int64_t s=0;
  const char* t = "abcdefghijklmnopqrstuvwxyz";
  for (int64_t i=0;i<n;i++){ s += (int64_t)strlen(t); }
  return (int)(s&0xFF);
}
C
    sed -i "s/N_PLACEHOLDER/${N}/" "$C_FILE"
    ;;
  box)
    HAKO_FILE=$(mktemp_hako)
    cat >"$HAKO_FILE" <<HAKO
static box Main { method main(args) {
  local n = ${N}
  local i = 0
  loop(i < n) { local t = new StringBox("x"); i = i + 1 }
  return 0
} }
HAKO
    C_FILE=$(mktemp_c)
    cat >"$C_FILE" <<'C'
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
typedef struct { char* p; } Str;
static inline Str* new_str(){ Str* s=(Str*)malloc(sizeof(Str)); s->p=strdup("x"); free(s->p); free(s); return s; }
int main(){ volatile int64_t n=N_PLACEHOLDER; for(int64_t i=0;i<n;i++){ new_str(); } return 0; }
C
    sed -i "s/N_PLACEHOLDER/${N}/" "$C_FILE"
    ;;
  *) echo "Unknown case: $CASE"; exit 2;;
esac

echo "[perf] case=$CASE n=$N runs=$RUNS backend=$BACKEND" >&2
sum_c=0; sum_h=0

if [[ "$EXE_MODE" = "1" ]]; then
  # Build C exe once
  C_EXE=$(mktemp --suffix .out)
  cc -O3 -march=native -o "$C_EXE" "$C_FILE"
  # Build Nyash exe once (requires llvm harness)
  if [[ "$BACKEND" != "llvm" ]]; then
    echo "[FAIL] --exe requires --backend llvm" >&2; exit 2
  fi
  if [[ ! -x "$ROOT/target/release/ny-llvmc" ]]; then
    (cargo build -q --release -p nyash-llvm-compiler >/dev/null 2>&1) || true
  fi
  HAKO_EXE=$(mktemp --suffix .out)
  TMP_JSON=$(mktemp --suffix .json)
  if ! HAKO_SELFHOST_BUILDER_FIRST=1 HAKO_MIR_BUILDER_LOOP_JSONFRAG=1 HAKO_MIR_BUILDER_JSONFRAG_NORMALIZE=1 \
       NYASH_ENABLE_USING=1 HAKO_ENABLE_USING=1 \
       NYASH_JSON_ONLY=1 bash "$ROOT/tools/hakorune_emit_mir.sh" "$HAKO_FILE" "$TMP_JSON" >/dev/null 2>&1; then
    echo "[FAIL] failed to emit MIR JSON" >&2; exit 3
  fi
  # Ensure runtime lib exists (nyash_kernel)
  (cd "$ROOT/crates/nyash_kernel" && cargo build -q --release >/dev/null) || true
  # Build EXE via helper (selects crate backend ny-llvmc under the hood)
  if ! NYASH_LLVM_BACKEND=crate \
       NYASH_NY_LLVM_COMPILER="${NYASH_NY_LLVM_COMPILER:-$ROOT/target/release/ny-llvmc}" \
       NYASH_EMIT_EXE_NYRT="${NYASH_EMIT_EXE_NYRT:-$ROOT/target/release}" \
       NYASH_LLVM_VERIFY=1 NYASH_LLVM_VERIFY_IR=1 NYASH_LLVM_FAST=1 \
       bash "$ROOT/tools/ny_mir_builder.sh" --in "$TMP_JSON" --emit exe -o "$HAKO_EXE" --quiet >/dev/null 2>&1; then
    echo "[FAIL] failed to build Nyash EXE" >&2; exit 3
  fi

  for i in $(seq 1 "$RUNS"); do
    t_c=$(time_exe_run "$C_EXE")
    t_h=$(time_exe_run "$HAKO_EXE")
    sum_c=$((sum_c + t_c)); sum_h=$((sum_h + t_h))
    if command -v python3 >/dev/null 2>&1; then
      ratio=$(python3 -c "print(round(${t_h}/max(${t_c},1)*100,2))" 2>/dev/null || echo NA)
    else
      ratio=NA
    fi
    echo "run#$i c=${t_c}ms hak=${t_h}ms ratio=${ratio}%" >&2
  done
  avg_c=$((sum_c / RUNS)); avg_h=$((sum_h / RUNS))
  echo "avg c=${avg_c}ms hak=${avg_h}ms" >&2
  if command -v python3 >/dev/null 2>&1; then
    python3 - <<PY
c=$avg_c; h=$avg_h
ratio = (h/max(c,1))*100.0
print(f"ratio={ratio:.2f}%")
PY
  fi
  rm -f "$C_EXE" "$HAKO_EXE" "$TMP_JSON" 2>/dev/null || true
else
  for i in $(seq 1 "$RUNS"); do
    t_c=$(bench_c "$C_FILE" "${C_FILE%.c}")
    t_h=$(bench_hako "$HAKO_FILE" "$BACKEND")
    sum_c=$((sum_c + t_c)); sum_h=$((sum_h + t_h))
    if command -v python3 >/dev/null 2>&1; then
      ratio=$(python3 -c "print(round(${t_h}/max(${t_c},1)*100,2))" 2>/dev/null || echo NA)
    else
      ratio=NA
    fi
    echo "run#$i c=${t_c}ms hak=${t_h}ms ratio=${ratio}%" >&2
  done
  avg_c=$((sum_c / RUNS)); avg_h=$((sum_h / RUNS))
  echo "avg c=${avg_c}ms hak=${avg_h}ms" >&2
  if command -v python3 >/dev/null 2>&1; then
    python3 - <<PY
c=$avg_c; h=$avg_h
ratio = (h/max(c,1))*100.0
print(f"ratio={ratio:.2f}%")
PY
  fi
fi

rm -f "$HAKO_FILE" "$C_FILE" "${C_FILE%.c}" 2>/dev/null || true