"""Assets-specific migration step.

Backfills fusion.asset from existing account.asset rows (Enterprise) so users
get all their existing assets in the Fusion namespace after switchover."""

import logging

from odoo import api, fields, models

_logger = logging.getLogger(__name__)


# Map Enterprise method names to Fusion method names
ENTERPRISE_METHOD_MAP = {
    'linear': 'straight_line',
    'degressive': 'declining_balance',
    'degressive_then_linear': 'declining_balance',  # simplified
    'manual': 'straight_line',
    'unit_of_production': 'units_of_production',
    'units_of_production': 'units_of_production',
}


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

    def _assets_bootstrap_step(self):
        """Backfill fusion.asset from account.asset (Enterprise) if it exists."""
        result = {
            'step': 'assets_bootstrap',
            'enterprise_module_present': False,
            'created': 0, 'skipped': 0, 'errors': [],
        }
        # Check if Enterprise account.asset exists
        AccountAsset = self.env.get('account.asset')
        if AccountAsset is None:
            result['enterprise_module_present'] = False
            return result
        result['enterprise_module_present'] = True

        FusionAsset = self.env['fusion.asset'].sudo()

        # Iterate Enterprise records
        company_id = self.company_id.id if 'company_id' in self._fields and self.company_id else None
        domain = []
        if company_id:
            domain.append(('company_id', '=', company_id))

        try:
            ea_records = AccountAsset.sudo().search(domain, limit=10000)
        except Exception as e:
            result['errors'].append(f"Enterprise search failed: {e}")
            return result

        for ea in ea_records:
            try:
                # Idempotent: skip if a fusion asset with same source name exists
                existing = FusionAsset.search([
                    ('name', '=', ea.name),
                    ('cost', '=', getattr(ea, 'original_value', 0) or 0),
                    ('company_id', '=', ea.company_id.id),
                ], limit=1)
                if existing:
                    result['skipped'] += 1
                    continue

                # Map state — Enterprise has 'draft', 'open' (running), 'paused', 'close' (disposed)
                ea_state = getattr(ea, 'state', 'draft')
                state_map = {'draft': 'draft', 'open': 'running',
                             'paused': 'paused', 'close': 'disposed',
                             'model': 'draft'}
                state = state_map.get(ea_state, 'draft')

                method = ENTERPRISE_METHOD_MAP.get(
                    getattr(ea, 'method', 'linear'), 'straight_line')

                FusionAsset.create({
                    'name': ea.name,
                    'cost': getattr(ea, 'original_value', 0) or 0,
                    'salvage_value': getattr(ea, 'salvage_value', 0) or 0,
                    'acquisition_date': getattr(ea, 'acquisition_date', False) or fields.Date.today(),
                    'in_service_date': getattr(ea, 'prorata_date', False) or False,
                    'method': method,
                    'useful_life_years': getattr(ea, 'method_number', 5) or 5,
                    'declining_rate_pct': getattr(ea, 'method_progress_factor', 0.2) * 100 if hasattr(ea, 'method_progress_factor') else 20.0,
                    'company_id': ea.company_id.id,
                    'state': state,
                })
                result['created'] += 1
            except Exception as e:
                result['errors'].append(f"Asset {ea.id}: {e}")

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

    def action_run_migration(self):
        """Override to add assets-bootstrap step."""
        result = super().action_run_migration() if hasattr(super(), 'action_run_migration') else None
        try:
            self._assets_bootstrap_step()
        except Exception as e:
            _logger.warning("assets_bootstrap_step failed: %s", e)
        return result