"""Followup-specific migration step.

Backfills fusion.followup.level from Enterprise's account_followup.followup.line
records (if Enterprise account_followup is installed)."""

import logging

from odoo import api, fields, models

_logger = logging.getLogger(__name__)


class FusionMigrationWizard(models.TransientModel):
    _inherit = "fusion.migration.wizard"

    def _followup_bootstrap_step(self):
        """Backfill fusion.followup.level from account_followup.followup.line."""
        result = {
            'step': 'followup_bootstrap',
            'enterprise_module_present': False,
            'created': 0, 'skipped': 0, 'errors': [],
        }

        # Enterprise's followup model — name varies by version
        EnterpriseLine = self.env.get('account_followup.followup.line')
        if EnterpriseLine is None:
            EnterpriseLine = self.env.get('account.followup.line')
        if EnterpriseLine is None:
            result['enterprise_module_present'] = False
            return result
        result['enterprise_module_present'] = True

        FusionLevel = self.env['fusion.followup.level'].sudo()
        try:
            ee_records = EnterpriseLine.sudo().search([])
        except Exception as e:
            result['errors'].append(f"Enterprise search failed: {e}")
            return result

        # Pick a starting offset that doesn't clash with anything already in
        # fusion_followup_level (seeded defaults at 1..3 plus any prior
        # migration runs). We allocate a unique sequence per Enterprise line
        # by max(existing) + 1, ensuring idempotency + within-batch uniqueness.
        existing_max = max(FusionLevel.search([]).mapped('sequence') or [100])
        next_seq = max(existing_max + 1, 101)

        # Map Enterprise tone-ish fields to ours
        for ee in ee_records:
            try:
                raw_seq = getattr(ee, 'sequence', None) or 50
                name = getattr(ee, 'name', None) or f"Migrated Level {raw_seq}"
                # Idempotency: skip if a level with same name was already
                # backfilled in a prior migration run.
                existing = FusionLevel.search([('name', '=', name)], limit=1)
                if existing:
                    result['skipped'] += 1
                    continue

                delay = getattr(ee, 'delay', None) or getattr(ee, 'delay_days', 7)
                # Enterprise tone heuristic: scale by sequence
                tone = 'gentle' if raw_seq <= 1 else 'firm' if raw_seq <= 2 else 'legal'

                with self.env.cr.savepoint():
                    FusionLevel.create({
                        'name': name,
                        'sequence': next_seq,
                        'delay_days': delay,
                        'tone': tone,
                        'active': True,
                    })
                next_seq += 1
                result['created'] += 1
            except Exception as e:
                result['errors'].append(f"Line {ee.id}: {e}")

        _logger.info(
            "fusion_accounting_followup migration: %d created, %d skipped, %d errors",
            result['created'], result['skipped'], len(result['errors']))
        return result

    def action_run_migration(self):
        result = super().action_run_migration() if hasattr(super(), 'action_run_migration') else None
        try:
            self._followup_bootstrap_step()
        except Exception as e:
            _logger.warning("followup_bootstrap_step failed: %s", e)
        return result