<?php

namespace Modules\Accounting\Services;

use App\HoldingEntity;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Facades\Schema;

class HoldingEntityResolutionService
{
    public function locationEntityMap(int $businessId): array
    {
        $map = [];

        $entities = HoldingEntity::where('business_id', $businessId)
            ->where('is_active', true)
            ->get(['id', 'meta']);

        foreach ($entities as $entity) {
            $locationId = (int) data_get($entity->meta, 'business_location_id', 0);
            if ($locationId > 0) {
                $map[$locationId] = (int) $entity->id;
            }
        }

        return $map;
    }

    public function resolveFromLocation(int $businessId, ?int $locationId): ?int
    {
        if (! $locationId) {
            return null;
        }

        return $this->locationEntityMap($businessId)[$locationId] ?? null;
    }

    public function assessTagging(int $businessId): array
    {
        $entityCount = HoldingEntity::where('business_id', $businessId)->where('is_active', true)->count();

        if ($entityCount === 0 || ! Schema::hasColumn('accounting_accounts_transactions', 'holding_entity_id')) {
            return [
                'entities' => $entityCount,
                'total_lines' => 0,
                'untagged_lines' => 0,
                'tagged_pct' => 100,
                'ready' => true,
            ];
        }

        $total = (int) DB::table('accounting_accounts_transactions as aat')
            ->join('accounting_accounts as aa', 'aa.id', '=', 'aat.accounting_account_id')
            ->where('aa.business_id', $businessId)
            ->count();

        $untagged = (int) DB::table('accounting_accounts_transactions as aat')
            ->join('accounting_accounts as aa', 'aa.id', '=', 'aat.accounting_account_id')
            ->where('aa.business_id', $businessId)
            ->whereNull('aat.holding_entity_id')
            ->count();

        $taggedPct = $total > 0 ? round((($total - $untagged) / $total) * 100, 1) : 100;

        return [
            'entities' => $entityCount,
            'total_lines' => $total,
            'untagged_lines' => $untagged,
            'tagged_pct' => $taggedPct,
            'ready' => $untagged === 0 || $taggedPct >= 80,
        ];
    }

    public function backfillUntagged(int $businessId): int
    {
        if (! Schema::hasColumn('accounting_accounts_transactions', 'holding_entity_id')
            || ! Schema::hasTable('transactions')) {
            return 0;
        }

        $locationMap = $this->locationEntityMap($businessId);
        if (empty($locationMap)) {
            return 0;
        }

        $updated = 0;

        foreach ($locationMap as $locationId => $entityId) {
            $updated += DB::table('accounting_accounts_transactions as aat')
                ->join('transactions as t', 't.id', '=', 'aat.transaction_id')
                ->join('accounting_accounts as aa', 'aa.id', '=', 'aat.accounting_account_id')
                ->where('aa.business_id', $businessId)
                ->whereNull('aat.holding_entity_id')
                ->where('t.location_id', $locationId)
                ->whereNotNull('aat.transaction_id')
                ->update(['aat.holding_entity_id' => $entityId]);
        }

        return $updated;
    }

    public function applyEntityScope($query, int $businessId, HoldingEntity $entity): void
    {
        if (! Schema::hasColumn('accounting_accounts_transactions', 'holding_entity_id')) {
            return;
        }

        $locationId = (int) data_get($entity->meta, 'business_location_id', 0);

        $query->where(function ($scoped) use ($entity, $locationId) {
            $scoped->where('aat.holding_entity_id', $entity->id);

            if ($locationId > 0 && Schema::hasTable('transactions')) {
                $scoped->orWhere(function ($fallback) use ($locationId) {
                    $fallback->whereNull('aat.holding_entity_id')
                        ->whereNotNull('aat.transaction_id')
                        ->whereIn('aat.transaction_id', function ($sub) use ($locationId) {
                            $sub->select('id')
                                ->from('transactions')
                                ->where('location_id', $locationId);
                        });
                });
            }
        });
    }
}