#!/usr/bin/env python3
"""
Backfill mass_kg in results.json for all DOE iterations.
Reads _temp_mass.txt (key=value format) and patches results.json.
"""
import json
from pathlib import Path

ITER_DIR = Path("/home/papa/atomizer/projects/hydrotech-beam/studies/01_doe_landscape/iterations")

fixed = 0
skipped = 0
errors = []

for iter_path in sorted(ITER_DIR.iterdir()):
    if not iter_path.is_dir() or not iter_path.name.startswith("iter"):
        continue

    mass_file = iter_path / "_temp_mass.txt"
    results_file = iter_path / "results.json"

    if not mass_file.exists():
        errors.append(f"{iter_path.name}: no _temp_mass.txt")
        continue
    if not results_file.exists():
        errors.append(f"{iter_path.name}: no results.json")
        continue

    # Parse mass
    content = mass_file.read_text().strip()
    if '=' in content:
        content = content.split('=', 1)[1]
    try:
        mass_kg = float(content)
    except ValueError:
        errors.append(f"{iter_path.name}: unparseable mass: {content!r}")
        continue

    # Patch results.json
    with open(results_file) as f:
        results = json.load(f)

    old_mass = results.get("mass_kg")
    results["mass_kg"] = mass_kg

    with open(results_file, 'w') as f:
        json.dump(results, f, indent=2)

    status = "NaN→fixed" if (old_mass is None or old_mass != old_mass) else f"{old_mass}→{mass_kg}"
    print(f"  {iter_path.name}: mass_kg = {mass_kg:.4f} kg  ({status})")
    fixed += 1

print(f"\n✅ Backfilled {fixed} iterations")
if skipped:
    print(f"⏭️  Skipped {skipped}")
if errors:
    print(f"❌ Errors: {len(errors)}")
    for e in errors:
        print(f"   {e}")