<?php

namespace App\Services;

use App\Enums\PurchasingRole;
use App\Models\Supplier;
use App\Models\SupplierBankDetail;
use App\Models\SupplierBankReview;
use App\Models\User;
use Illuminate\Support\Facades\DB;
use Illuminate\Validation\ValidationException;

class SupplierBankWorkflow
{
    private function actor(User $user, Supplier $supplier): void
    {
        abort_unless(auth()->id() === $user->id && $user->tenant_id !== null && $supplier->tenant_id === $user->tenant_id, 403);
        if (app(ConflictGuard::class)->hasConflict($user->id, $supplier->id, null)) {
            throw ValidationException::withMessages(['bank' => 'Conflito de interesses com este fornecedor.']);
        }
    }

    /** @param array<string,mixed> $data */
    public function propose(User $user, Supplier $supplier, array $data): SupplierBankDetail
    {
        $this->actor($user, $supplier);
        abort_unless($user->purchasing_role === PurchasingRole::Procurement, 403);

        return DB::transaction(function () use ($user, $supplier, $data) {
            app(ConflictGuard::class)->lockCompany($user);
            $user = app(CurrentActor::class)->lock($user, [PurchasingRole::Procurement]);
            $supplier = Supplier::query()->lockForUpdate()->findOrFail($supplier->id);
            $this->actor($user, $supplier);
            $latest = SupplierBankDetail::query()->where('supplier_id', $supplier->id)->latest('revision')->first();
            if ((int) $data['previous_id'] !== ($latest->id ?? 0)) {
                throw ValidationException::withMessages(['previous_id' => 'Dados bancários alterados. Reabra a ficha antes de propor outra versão.']);
            }
            $detail = SupplierBankDetail::query()->create(['tenant_id' => $user->tenant_id, 'supplier_id' => $supplier->id, 'created_by' => $user->id, 'revision' => ($latest->revision ?? 0) + 1, ...array_intersect_key($data, array_flip(['bank_name', 'country', 'currency', 'beneficiary', 'account_identifier', 'evidence_reference', 'reason'])), 'created_at' => now()]);
            app(RequisitionWorkflow::class)->audit($user, 'supplier.bank_proposed', null, null, ['supplier_id' => $supplier->id, 'bank_detail_id' => $detail->id, 'revision' => $detail->revision]);

            return $detail;
        });
    }

    public function review(User $user, SupplierBankDetail $detail, string $decision, string $reason): void
    {
        abort_unless($user->purchasing_role === PurchasingRole::Finance && $detail->tenant_id === $user->tenant_id && $detail->created_by !== $user->id, 403);
        if (! in_array($decision, ['approved', 'rejected']) || trim($reason) === '') {
            throw ValidationException::withMessages(['bank' => 'Decisão e fundamento obrigatórios.']);
        }
        DB::transaction(function () use ($user, $detail, $decision, $reason) {
            app(ConflictGuard::class)->lockCompany($user);
            $user = app(CurrentActor::class)->lock($user, [PurchasingRole::Finance]);
            $supplier = Supplier::query()->lockForUpdate()->findOrFail($detail->supplier_id);
            $this->actor($user, $supplier);
            $latest = SupplierBankDetail::query()->where('supplier_id', $supplier->id)->latest('revision')->firstOrFail();
            if ($latest->id !== $detail->id) {
                throw ValidationException::withMessages(['bank' => 'Versão substituída. Reveja os dados bancários actuais.']);
            }
            $existing = SupplierBankReview::query()->where('supplier_bank_detail_id', $detail->id)->where('reviewed_by', $user->id)->first();
            if ($existing) {
                if ($existing->decision !== $decision || $existing->reason !== $reason) {
                    throw ValidationException::withMessages(['bank' => 'A decisão anterior é imutável. Proponha nova versão para corrigir dados.']);
                }

                return;
            }
            if (! $supplier->eligible() || SupplierBankReview::query()->where('supplier_bank_detail_id', $detail->id)->where('decision', 'rejected')->exists() || SupplierBankReview::query()->where('supplier_bank_detail_id', $detail->id)->count() >= 2) {
                throw ValidationException::withMessages(['bank' => 'Fornecedor não elegível ou versão já decidida.']);
            }
            SupplierBankReview::query()->create(['tenant_id' => $user->tenant_id, 'supplier_bank_detail_id' => $detail->id, 'reviewed_by' => $user->id, 'decision' => $decision, 'reason' => $reason, 'created_at' => now()]);
            app(RequisitionWorkflow::class)->audit($user, 'supplier.bank_'.$decision, null, null, ['supplier_id' => $supplier->id, 'bank_detail_id' => $detail->id]);
        });
    }

    /** Re-evaluate inside the payment transaction in the future; UI readiness is not authorisation. */
    public function state(Supplier $supplier): string
    {
        $detail = SupplierBankDetail::query()->where('supplier_id', $supplier->id)->latest('revision')->first();
        if (! $detail) {
            return 'missing';
        }
        $reviews = SupplierBankReview::query()->where('supplier_bank_detail_id', $detail->id)->get();
        if ($reviews->contains('decision', 'rejected')) {
            return 'rejected';
        }
        if ($reviews->count() < 2) {
            return 'pending';
        }
        if (! $supplier->eligible() || app(ConflictGuard::class)->hasConflict($detail->created_by, $supplier->id, null)) {
            return 'blocked';
        }
        foreach ($reviews as $review) {
            $user = User::query()->where('tenant_id', $supplier->tenant_id)->find($review->reviewed_by);
            if (! $user || $user->purchasing_role !== PurchasingRole::Finance || $user->id === $detail->created_by || app(ConflictGuard::class)->hasConflict($user->id, $supplier->id, null)) {
                return 'blocked';
            }
        }

        return 'approved';
    }
}