<?php

namespace Modules\IndustrialEngineering\Services;

use Illuminate\Database\Eloquent\Model;
use Illuminate\Support\Str;

class CodeGeneratorService
{
    /** @var array<string, string> */
    protected array $prefixes = [
        'product' => 'PRD',
        'line' => 'LIN',
        'machine' => 'MCH',
        'item' => 'ITM',
        'revision' => 'REV',
        'bom' => 'BOM',
        'scenario' => 'CST',
        'release' => 'REL',
        'unit' => 'UNT',
        'asset' => 'AST',
        'sourcing' => 'SRC',
        'research' => 'RND',
        'eco' => 'ECO',
    ];

    public function suggest(string $type, int $businessId): string
    {
        $prefix = $this->prefixes[$type] ?? strtoupper(Str::substr($type, 0, 3));
        $year = now()->format('Y');
        $seq = $this->nextSequence($type, $businessId);

        return sprintf('IE-%s-%s-%04d', $prefix, $year, $seq);
    }

    /**
     * Resolve user code: manual if provided, otherwise auto-generated unique code.
     */
    public function resolveCode(string $type, int $businessId, ?string $manualCode, Model $model, string $codeColumn = 'platform_code'): array
    {
        $autoCode = $this->suggest($type, $businessId);

        while ($this->codeExists($model, $businessId, 'auto_code', $autoCode)) {
            $autoCode = $this->suggest($type, $businessId);
        }

        $manual = trim((string) $manualCode);
        $effectiveCode = $manual !== '' ? $manual : $autoCode;

        if ($this->codeExists($model, $businessId, $codeColumn, $effectiveCode)) {
            throw new \InvalidArgumentException(__('industrialengineering::lang.code_already_exists', ['code' => $effectiveCode]));
        }

        return [
            'auto_code' => $autoCode,
            $codeColumn => $effectiveCode,
        ];
    }

    protected function codeExists(Model $model, int $businessId, string $column, string $code): bool
    {
        $query = $model->newQuery()->where('business_id', $businessId)->where($column, $code);

        return $query->exists();
    }

    protected function nextSequence(string $type, int $businessId): int
    {
        $map = [
            'product' => [\Modules\IndustrialEngineering\Models\ProductPlatform::class, 'auto_code'],
            'line' => [\Modules\IndustrialEngineering\Models\LineTemplate::class, 'auto_code'],
            'machine' => [\Modules\IndustrialEngineering\Models\LineTemplate::class, 'auto_code'],
            'item' => [\Modules\IndustrialEngineering\Models\ItemMaster::class, 'auto_code'],
            'revision' => [\Modules\IndustrialEngineering\Models\LineRevision::class, 'auto_code'],
            'bom' => [\Modules\IndustrialEngineering\Models\Bom::class, 'auto_code'],
            'eco' => [\Modules\IndustrialEngineering\Models\EngineeringChangeOrder::class, 'auto_code'],
        ];

        if (! isset($map[$type])) {
            return random_int(1, 9999);
        }

        [$class, $col] = $map[$type];
        $year = now()->format('Y');
        $prefix = $this->prefixes[$type] ?? 'GEN';

        $last = $class::where('business_id', $businessId)
            ->where($col, 'like', "IE-{$prefix}-{$year}-%")
            ->orderByDesc($col)
            ->value($col);

        if (! $last || ! preg_match('/-(\d{4})$/', $last, $m)) {
            return 1;
        }

        return (int) $m[1] + 1;
    }
}