<?php

namespace App\Services\Holding;

use App\EmploymentAssignment;
use Illuminate\Database\Query\Builder;
use Illuminate\Support\Facades\Schema;

class AssignmentQueryScopeService
{
    public function __construct(protected ContextAssignmentService $contextAssignmentService) {}

    public function activeAssignment(?\App\User $user = null): ?EmploymentAssignment
    {
        $user = $user ?? auth()->user();

        if (! $user) {
            return null;
        }

        return $this->contextAssignmentService->getActiveAssignment($user);
    }

    /**
     * Apply holding assignment scopes to a query builder when RBAC is enabled.
     *
     * @param  array<string, string>  $columnMap  e.g. ['holding_entity_id' => 'transactions.holding_entity_id', 'location_id' => 'transactions.location_id']
     */
    public function applyToQuery(Builder $query, ?EmploymentAssignment $assignment = null, array $columnMap = []): Builder
    {
        if (! config('constants.enable_holding_context_rbac', false)) {
            return $query;
        }

        $assignment = $assignment ?? $this->activeAssignment();

        if (! $assignment || $assignment->scopes->isEmpty()) {
            return $query;
        }

        foreach ($assignment->scopes as $scope) {
            $column = $columnMap[$scope->scope_key] ?? $scope->scope_key;

            if (! $this->columnResolvable($column)) {
                continue;
            }

            if ($scope->scope_value === '*' || $scope->scope_value === null) {
                continue;
            }

            $values = array_filter(array_map('trim', explode(',', (string) $scope->scope_value)));

            if (empty($values)) {
                continue;
            }

            $query->whereIn($column, $values);
        }

        return $query;
    }

    public function allowedEntityIds(?EmploymentAssignment $assignment = null): ?array
    {
        if (! config('constants.enable_holding_context_rbac', false)) {
            return null;
        }

        $assignment = $assignment ?? $this->activeAssignment();

        if (! $assignment) {
            return null;
        }

        $entityScope = $assignment->scopes->firstWhere('scope_key', 'holding_entity_id');

        if (! $entityScope || $entityScope->scope_value === '*') {
            return $assignment->entity_id ? [(int) $assignment->entity_id] : null;
        }

        return array_map('intval', array_filter(explode(',', (string) $entityScope->scope_value)));
    }

    public function allowedLocationIds(?EmploymentAssignment $assignment = null): ?array
    {
        if (! config('constants.enable_holding_context_rbac', false)) {
            return null;
        }

        $assignment = $assignment ?? $this->activeAssignment();

        if (! $assignment) {
            return null;
        }

        $locationScope = $assignment->scopes->firstWhere('scope_key', 'location_id');

        if (! $locationScope || $locationScope->scope_value === '*') {
            return null;
        }

        return array_map('intval', array_filter(explode(',', (string) $locationScope->scope_value)));
    }

    protected function columnResolvable(string $column): bool
    {
        if (str_contains($column, '.')) {
            return true;
        }

        return Schema::hasColumn('transactions', $column);
    }
}