"""
Diagnostic script to inspect OP2 file contents
Helps identify what data is available and what's missing
"""
import sys
from pathlib import Path

# Add project root to path
project_root = Path(__file__).resolve().parents[2]
sys.path.insert(0, str(project_root))

from pyNastran.op2.op2 import read_op2

# Path to OP2 file
op2_file = Path(__file__).parent / "1_setup" / "model" / "bracket_sim1-solution_1.op2"

if not op2_file.exists():
    print(f"[ERROR] OP2 file not found: {op2_file}")
    sys.exit(1)

print("="*70)
print("OP2 FILE DIAGNOSTIC")
print("="*70)
print(f"File: {op2_file}")
print(f"Size: {op2_file.stat().st_size:,} bytes")
print()

# Load OP2 file
print("[1/3] Loading OP2 file...")
op2 = read_op2(str(op2_file), debug=False)
print("      [OK] OP2 file loaded successfully")
print()

# Check for Grid Point Weight (Mass Properties)
print("[2/3] Checking for Grid Point Weight (GRDPNT)...")
if hasattr(op2, 'grid_point_weight'):
    if op2.grid_point_weight:
        gpw = op2.grid_point_weight
        print("      [OK] Grid Point Weight data found!")
        print()
        print("      Available attributes:")
        for attr in dir(gpw):
            if not attr.startswith('_'):
                print(f"        - {attr}")
        print()

        # Check for MO matrix
        if hasattr(gpw, 'MO'):
            print(f"      [OK] MO matrix found: {gpw.MO}")
            if gpw.MO is not None and len(gpw.MO) > 0:
                mass_ton = gpw.MO[0, 0]
                mass_kg = mass_ton * 1000.0
                print(f"      [OK] Mass: {mass_kg:.6f} kg ({mass_ton:.6e} ton)")
            else:
                print("      [X] MO matrix is empty or None")
        else:
            print("      [X] MO matrix not found")

        # Check for CG
        if hasattr(gpw, 'cg'):
            print(f"      [OK] CG found: {gpw.cg}")
        else:
            print("      [!] CG not found")

        # Check reference point
        if hasattr(gpw, 'reference_point'):
            print(f"      [OK] Reference point: {gpw.reference_point}")
        else:
            print("      [!] Reference point not found")
    else:
        print("      [X] grid_point_weight attribute exists but is empty/None")
else:
    print("      [X] No grid_point_weight attribute found")
    print()
    print("      GRDPNT output request is NOT enabled in Nastran")
    print("      Solution:")
    print("      1. Open Bracket_fem1.fem in NX")
    print("      2. Enable GRDPNT in Case Control or Bulk Data")
    print("      3. Save the FEM file")
    print("      4. Re-run the optimization")

print()

# Check for Grid Point Forces
print("[3/3] Checking for Grid Point Forces (GPFORCE)...")
if hasattr(op2, 'grid_point_forces'):
    if op2.grid_point_forces:
        print("      [OK] Grid Point Forces data found!")
        print(f"      Subcases available: {list(op2.grid_point_forces.keys())}")
    else:
        print("      [X] grid_point_forces attribute exists but is empty")
else:
    print("      [X] No grid_point_forces found (expected - using applied_force parameter)")

print()
print("="*70)
print("DIAGNOSIS COMPLETE")
print("="*70)

# Summary
print()
print("SUMMARY:")
has_mass = hasattr(op2, 'grid_point_weight') and op2.grid_point_weight
if has_mass:
    print("[OK] Mass extraction should work")
else:
    print("[X] Mass extraction will FAIL - GRDPNT not enabled")
    print()
    print("NEXT STEPS:")
    print("1. In NX, open: studies/bracket_stiffness_optimization/1_setup/model/Bracket_fem1.fem")
    print("2. Go to: File > Utilities > Customer Defaults")
    print("3. Search for: GRDPNT")
    print("4. OR: Add 'PARAM,GRDPNT,0' to Bulk Data section")
    print("5. Save and close")
    print("6. Re-run optimization")