<?php

namespace App\Services\Stats;

use App\Models\Stats\Dimensions\DimClient;
use App\Models\Stats\Dimensions\DimProduct;
use Carbon\Carbon;
use Illuminate\Support\Facades\DB;

class DimensionSyncService
{
    /**
     * 고객 차원 동기화 (SCD Type 2)
     */
    public function syncClients(int $tenantId): int
    {
        $today = Carbon::today()->format('Y-m-d');
        $synced = 0;

        $clients = DB::connection('mysql')
            ->table('clients')
            ->where('tenant_id', $tenantId)
            ->select('id', 'tenant_id', 'name', 'client_group_id', 'client_type')
            ->get();

        foreach ($clients as $client) {
            $groupName = null;
            if ($client->client_group_id) {
                $groupName = DB::connection('mysql')
                    ->table('client_groups')
                    ->where('id', $client->client_group_id)
                    ->value('group_name');
            }

            $current = DimClient::where('tenant_id', $tenantId)
                ->where('client_id', $client->id)
                ->where('is_current', true)
                ->first();

            if (! $current) {
                DimClient::create([
                    'tenant_id' => $tenantId,
                    'client_id' => $client->id,
                    'client_name' => $client->name,
                    'client_group_id' => $client->client_group_id,
                    'client_group_name' => $groupName,
                    'client_type' => $client->client_type,
                    'region' => null,
                    'valid_from' => $today,
                    'valid_to' => null,
                    'is_current' => true,
                ]);
                $synced++;

                continue;
            }

            $changed = $current->client_name !== $client->name
                || $current->client_group_id != $client->client_group_id
                || $current->client_type !== $client->client_type;

            if ($changed) {
                $current->update([
                    'valid_to' => $today,
                    'is_current' => false,
                ]);

                DimClient::create([
                    'tenant_id' => $tenantId,
                    'client_id' => $client->id,
                    'client_name' => $client->name,
                    'client_group_id' => $client->client_group_id,
                    'client_group_name' => $groupName,
                    'client_type' => $client->client_type,
                    'region' => null,
                    'valid_from' => $today,
                    'valid_to' => null,
                    'is_current' => true,
                ]);
                $synced++;
            }
        }

        return $synced;
    }

    /**
     * 제품(품목) 차원 동기화 (SCD Type 2)
     */
    public function syncProducts(int $tenantId): int
    {
        $today = Carbon::today()->format('Y-m-d');
        $synced = 0;

        $items = DB::connection('mysql')
            ->table('items')
            ->where('tenant_id', $tenantId)
            ->where('is_active', true)
            ->select('id', 'tenant_id', 'code', 'name', 'item_type', 'category_id')
            ->get();

        foreach ($items as $item) {
            $categoryName = null;
            if ($item->category_id) {
                $categoryName = DB::connection('mysql')
                    ->table('categories')
                    ->where('id', $item->category_id)
                    ->value('name');
            }

            $current = DimProduct::where('tenant_id', $tenantId)
                ->where('item_id', $item->id)
                ->where('is_current', true)
                ->first();

            if (! $current) {
                DimProduct::create([
                    'tenant_id' => $tenantId,
                    'item_id' => $item->id,
                    'item_code' => $item->code,
                    'item_name' => $item->name,
                    'item_type' => $item->item_type,
                    'category_id' => $item->category_id,
                    'category_name' => $categoryName,
                    'valid_from' => $today,
                    'valid_to' => null,
                    'is_current' => true,
                ]);
                $synced++;

                continue;
            }

            $changed = $current->item_name !== $item->name
                || $current->item_code !== $item->code
                || $current->item_type !== $item->item_type
                || $current->category_id != $item->category_id;

            if ($changed) {
                $current->update([
                    'valid_to' => $today,
                    'is_current' => false,
                ]);

                DimProduct::create([
                    'tenant_id' => $tenantId,
                    'item_id' => $item->id,
                    'item_code' => $item->code,
                    'item_name' => $item->name,
                    'item_type' => $item->item_type,
                    'category_id' => $item->category_id,
                    'category_name' => $categoryName,
                    'valid_from' => $today,
                    'valid_to' => null,
                    'is_current' => true,
                ]);
                $synced++;
            }
        }

        return $synced;
    }
}