"""
CI management command: check for drift between workout_research.md
calibration values and WorkoutType DB records.

Usage:
    python manage.py check_rules_drift
    python manage.py check_rules_drift --verbosity 2
"""

import sys

from django.core.management.base import BaseCommand

from generator.models import WorkoutType
from generator.rules_engine import DB_CALIBRATION


class Command(BaseCommand):
    help = (
        'Check for drift between research doc calibration values '
        'and WorkoutType DB records. Exits 1 if mismatches found.'
    )

    # Fields to compare between DB_CALIBRATION and WorkoutType model
    FIELDS_TO_CHECK = [
        'duration_bias',
        'typical_rest_between_sets',
        'typical_intensity',
        'rep_range_min',
        'rep_range_max',
        'round_range_min',
        'round_range_max',
        'superset_size_min',
        'superset_size_max',
    ]

    def handle(self, *args, **options):
        verbosity = options.get('verbosity', 1)
        mismatches = []
        missing_in_db = []
        checked = 0

        for type_name, expected_values in DB_CALIBRATION.items():
            try:
                wt = WorkoutType.objects.get(name=type_name)
            except WorkoutType.DoesNotExist:
                missing_in_db.append(type_name)
                continue

            for field_name in self.FIELDS_TO_CHECK:
                if field_name not in expected_values:
                    continue

                expected = expected_values[field_name]
                actual = getattr(wt, field_name, None)
                checked += 1

                if actual != expected:
                    mismatches.append({
                        'type': type_name,
                        'field': field_name,
                        'expected': expected,
                        'actual': actual,
                    })
                elif verbosity >= 2:
                    self.stdout.write(
                        f"  OK  {type_name}.{field_name} = {actual}"
                    )

        # Report results
        self.stdout.write('')
        self.stdout.write(f'Checked {checked} field(s) across {len(DB_CALIBRATION)} workout types.')
        self.stdout.write('')

        if missing_in_db:
            self.stdout.write(self.style.WARNING(
                f'Missing from DB ({len(missing_in_db)}):'
            ))
            for name in missing_in_db:
                self.stdout.write(f'  - {name}')
            self.stdout.write('')

        if mismatches:
            self.stdout.write(self.style.ERROR(
                f'DRIFT DETECTED: {len(mismatches)} mismatch(es)'
            ))
            self.stdout.write('')
            header = f'{"Workout Type":<35} {"Field":<30} {"Expected":<15} {"Actual":<15}'
            self.stdout.write(header)
            self.stdout.write('-' * len(header))
            for m in mismatches:
                self.stdout.write(
                    f'{m["type"]:<35} {m["field"]:<30} '
                    f'{str(m["expected"]):<15} {str(m["actual"]):<15}'
                )
            self.stdout.write('')
            self.stdout.write(self.style.ERROR(
                'To fix: update WorkoutType records in the DB or '
                'update DB_CALIBRATION in generator/rules_engine.py.'
            ))
            sys.exit(1)
        else:
            self.stdout.write(self.style.SUCCESS(
                'No drift detected. DB values match research calibration.'
            ))